Spirent Test Methodology QoS Testing
Test Methodology Journal
Definitive Guide to
Quality of Service (QoS)Testing
April 2008
Inspired Innovation
Spirent Communications Test Methodologies Definitive Guide to QoS Testing
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Table of Contents
Introduction 2
Layer 2 CoS Verification Testing 4
Layer 3 QoS Verification Testing 128
Layer 3 QoS Control Plane Verification 269
Glossary 428
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Introduction
Quality of Service, or QoS, testing is the set of processes and test cases to verify that services are given the
correct amount of resources at the network forwarding and transport layer. QoS allows the user to configure
differentiated services either as a global policy or as an SLA service level.
Thus, Quality of Service is the ability to control the characteristics of ongoing communication
services. Service providers use these control values to offer improved and possibly contract levels of
service. QoS is an end-to-end responsibility that involves clients, switches, routers and servers.
The manner in which remarked packets are presented to the user allows or breaks a device’s ability to
forward traffic according to a policy. For example, steady state traffic may forward correctly, but bursts of
traffic such as a flood of VoIP or video traffic may break the QoS policy. Testing with real-word traffic
patterns becomes critical because it is possible to spend valuable time configuring a test that lacks real-
world application.
Spirent TestCenter™ is the best platform for testing L3 and L4 QoS. TestCenter generates differentiated and
marked traffic, and also mixes VBR (Variable Bit Rate traffic such as MPEG-2/4 or SIP) and CBR (Constant
Bit Rate, or Steady State such as data) traffic out the same port at the same time.
From a QoS queue management perspective, it is much harder to forward bursts of unexpected but higher
priority traffic compared with classic, repetitive traffic. This traffic differs from other testers by forcing more
CPU look-ups as the Device Under Test (DUT) would experience in a production network.
The user will be able to correctly emulate real-world conditions by properly constructing correct,
differentiated traffic such as:
Figure 1 – Proper QoS Per Port Pattern – Unique to Spirent TestCenter
Also, QoS Testing requires loading and deep, single-pass inspection of performance. QoS in the real world
is never an analysis of a single metric but a mix of simultaneous matrices. The first step in testing is to
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DUT
3
2 1
λ2 λ1
True Jitter (Min) = Min {Ι(ζ1- λ1)Ι, Ι(ζ2- λ2)Ι, …,Ι(ζn- λn)Ι}
True Jitter (Avg) = Ι(ζn- λn)Ι
TX Port
RX Port
3
2 1
ζ2
ζ1
Stream1
3
2 1
λ2 λ1
Stream2 (VBR – Variable Bit Rate)
3
2 1
ζ2
ζ1
Stream2
3
2 1
λ2 λ1
Stream3 (Out of Order)
2
3 1
ζ2
ζ1
Stream3
Stream1 (CBR – Constant Bit Rate)
True Jitter (Max) = Max {Ι(ζ1- λ1)Ι, Ι(ζ2- λ2)Ι, …,Ι(ζn- λn)Ι}
N=1
Z
Where there are Z
Packets
Z
congest. With over 32K TX streams and real-time analysis of over 64K stream, measuring up to 41x
simultaneous metrics per stream, Spirent TestCenter becomes the only viable platform to test QoS.
Spirent TestCenter simultaneously congests the DUT to turn on QoS and measure all required metrics
necessary to properly assess QoS. For Example, TestCenter is the only platform that can measure true jitter.
This is critical to QoS testing because only true jitter can measure the effect of latency variation on Triple
Play traffic.
Spirent TestCenter True Jitter is defined as the following (per industry standard MEF 10.1):
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Layer 2 CoS Verification Testing
Introduction 5
Validating Source Port Priority for Layer 2 Ethernet 7
Verifying L2 Ethernet QoS by MAC Address Range 26
VLAN 802.1pq Remarking Validation 44
VLAN 802.1q VLAN Remarking Validation 69
802.1q in a Mixed Tag Environment 91
Testing Committed Information Rate (CIR) by Layer 2 Ethernet Port 114
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Introduction
Layer 2 CoS testing allows the user to test the DUT’s ability to edit the Cost of Service (CoS) using a variety
of mechanisms such as queuing by MAC address range, port and with IEEE 802.1QP VLAN tags. This is
differentiated from best effort or unprioritized traffic.
DA SA TAG
n
PriorityTPID CFI VLAN ID
12 bits1 Bit3 Bits16 Bits
TAG
n-1
PriorityTPID CFI VLAN ID
12 bits1 Bit3 Bits16 Bits
Payload CRC
IEEE 802.1P is an extension of the IEEE 802.1Q (VLANs tagging) standard. The two standards work in
tandem. The 802.1Q standard specifies a tag that appends to an Ethernet MAC frame. The VLAN tag has
two parts: The VLAN ID (12-bit) and Prioritization (3-bit). The prioritization field was not defined and used in
the 802.1Q VLAN standard. The 802.1P defines this prioritization field.
The 802.1P queues CoS network prioritization has the following broad recommendations:
802.1P Value Traffic Type
0 Best Effort
1 Background
2 Spare
3 Excellent Effort
4 Controlled Load
5 Video
6 Voice
7 Network Control
Class of Service (CoS) is a way of managing traffic in a network by grouping similar types of traffic (e-mail,
streaming video, voice, large document file transfer) together and treating each type as a class with its own
level of service priority. Unlike Quality of Service (QoS) traffic management, Class of Service technologies
do not guarantee a level of service in terms of bandwidth and delivery time; they offer a "best effort”.
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On the other hand, CoS technology is simpler to manage and more scalable as a network grows in structure
and traffic volume. Consider CoS as "coarsely grained" traffic control and QoS as "finely grained" traffic
control.
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Validating Source Port Priority for Layer 2 Ethernet
Associated RFCs
• IEEE 802.2
Spirent Communications Test Equipment Needed
• 5 Ethernet Ports, 10/100/1000 or 10 GigE
• Spirent TestCenter Chassis
• Miscellaneous Cables
Objective
The objective of this test case to determine if the Device Under Test (DUT) is properly processing traffic set
in a Layer 2 (L2) Quality of Service (QoS) policy by Source port. This test will determine, in a congested
state, whether the DUT will selectively delay and drop traffic from lower priority ports in favor of higher
priority ports. The DUT will pass this test if it can maintain the following attributes by class over the
duration of the test.
Packet Loss
( Frame Count)
Sequence Errors
( Frame Count)
Max Latency
(milliseconds)
Network Control 0 0 7 ms
Real-Time 1000 10 10 ms
Best Effort Any Any Any
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Best Effort
QoS High
QoS Medium
DUT
Network Control
Real-Time
Best Effort
Best Effort
QoS High
QoS Medium
Oversubscribed
Port
Oversubscribed
Port
Source Generation Domain QoS Impairment
Domain
QoS Analysis Domain
Setup
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Step-by-Step
1. Configure DUT
Login to your DUT. Place all five ports in the same Virtual Local Area Network (VLAN). Turn off all
protocols except L2 forwarding and L2 QoS shaping. Configure Port 1 on the DUT as highest
Possible Priority, Configure Port 2 as Second Highest, and Configure Port 3 as Best Effort.
Configure ports four and five with no shaping in or outbound.
2. Cable DUT to Spirent TestCenter
Plug all five ports sequentially into five sequential Spirent TestCenter ports.
3. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter GUI and reserve the required ports.
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4. Rename Your Spirent TestCenter Ports
In your test tree, click on All Ports. For each port, uncheck Append Location to Port Name. Starting
at the top port, click on the Port Name Cell and rename the port to Network Control. Proceed down
the list and name the ports Real-Time Control, Best Effort, Over Subscribed Port 1 and Over
Subscribed Port 2.
5. Create Host Blocks
Right-click on the All Ports Æ All Hosts. Click on Add Multiple Hosts.
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6. Host Block Port Selection
Select all the ports and press Next.
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7. Select Protocols
The defaults are okay, press Next to continue.
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8. Select Encapsulation
Set the Upper Layer protocol to None and hit Next to continue.
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9. Configure Hosts
Under Hosts per port, type “20,000”. Also, check Launch Traffic Wizard after generating Hosts and
then press Finish.
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10. Setup Traffic
In the following step, each of the three transmitting ports will transmit 50% load to each of the two
oversubscribed ports. In the Traffic Wizard, select all ports and hit Next.
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11. Endpoint Configuration
Under Distribution, check backbone. Make sure Encapsulation is EthernetII. For the Source ports,
select Network Control, Real-Time Control and Best Effort. Under Destination, select Over
Subscribed Port 1 and Over Subscribed Port 2. Uncheck “Stream only generation”. Press Finish.
12. Set TX Port Rates
Under All Ports Æ All Traffic Generators, find the Load column and set the first three ports to
100%.
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13. Set QoS Policies
Under Tools, select Service Class Builder.
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14. Configuring Service Classes
Check the “+ Service Class” button three times. Name the top cell “Network Control”. Name the
second cell “Real Time” and the third cell “Best Effort”. Change Results View Mode to “Histogram”
and click on “+ Parameter” and Add Frame Loss, Out of Sequence and Max Latency.
Set the Following Values:
Frame Loss Out of Sequence Max Latency
Network
Control
0<=x<=0 0<=x<=0 0<=x<=7
Real-Time 0<=x<=1000 0<=x<=10 0<=x<=7
Best Effort 0<=x<=1844674407470955199 0<=x<=1844674407470955199 0<=x<=37580963
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15. Mapping Class
Press the mapping Tab. Under Traffic Group, click the Click Here hyperlink.
16. Configuring Traffic Groups
Under Traffic group, type Service Class and select Add. Under Traffic Subgroup, add Network
Control, Real-Time and Best Effort. Press OK once completed.
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17. Setting Traffic Groups
Under Traffic Group, select Network Control and under Service Class also select Network Control.
Press Add. Repeat for the remaining two groups. Finally, press OK to continue with the test
configuration.
18. Bind QoS Profiles to Traffic
Under All Ports Æ All Stream Blocks, under name, rename the first Stream Block to Network
Control and rename remaining Stream Blocks accordingly.
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19. Setting Traffic Groups.
Scroll to the right till the Traffic Group column is visible. Select the “…” button which appears
when selected.
20. Subgroup Selection
Use the Subgroup drop down menu and select the corresponding Subgroup. Press OK once
completed. Repeat steps 19 and 20 for Real-Time Control and Best Effort.
21. Add Automation across Frame Sizes
In the toolbar, select the Wizards button. Under Configuration Wizards Æ Sequence Generator, run
the Custom Test. Select Next to continue with the configuration.
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22. Configuration of Test
Click the Enable Preview checkbox. Under Test Type, pick Step. Set the duration to 360 seconds.
Under load, select Custom and type in 100. Under Frame size, check step with a Start of 64, Stop
at 1518, and a Step of 64. Press Next once the configuration is completed.
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23. Optional Configuration
Under Optional Commands, check L2 Learning and Check “Before each iteration”. Check “Save
detailed stream results with every iteration”. Press Finish.
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24. Run Test
In the Command Sequencer, choose the Run button.
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25. Results Report
At the end of each first iteration, the Results Reporter will launch and populate results. After each
iteration, the new results will also be populated.
Analysis
26. Determining Pass or Fail
For each Frame Size Iteration in the Results Reporter, select the “ServiceClassValidation”
template. Next, click the Test Summary tab. Here you will see if each service class level passed or
not. Repeat for each frame size. When finished, it is possible to export the report to PDF or HTML.
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Best Effort
QoS High
QoS Medium
DUT
Network Control
Real-Time
Best Effort
Best Effort
QoS High
QoS Medium
Oversubscribed
Port
Oversubscribed
Port
Source Generation Domain QoS Impairment
Domain
QoS Analysis Domain
Verifying L2 Ethernet QoS by MAC Address Range
Associated RFCs
• IEEE 802.2
Spirent Communications Test Equipment Needed
• 5 Ethernet Ports, 10/100/1000 or 10 GigE
• Spirent TestCenter Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to inject ranges of MAC Address to a congested port and verify Quality of
Service (QoS) by Range of MAC addresses. We will set up three levels of MAC address pools and use the
following QoS Table:
Packet Loss
( Frame Count)
Sequence Errors
( Frame Count)
Max Latency
( milliseconds)
Network Control 0 0 7 ms
Real-Time 1000 10 10 ms
Best Effort Any Any Any
Setup
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Step-by-Step
1. Configure Device Under Test (DUT)
Log in to your DUT. Set up three MAC address QoS pools.
Network Control :00:10:94:00:00:01 + 200K Addresses
Real Time Control: 00;10:94:03:0D:41 + 200K Addresses
Best Effort: 00:10:94:06:1A:81+ 200K Addresses
2. Cable DUT to Spirent TestCenter
Plug all five ports sequentially into five sequential Spirent TestCenter ports.
3. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter GUI and reserve the required ports.
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4. Rename Your Spirent TestCenter Ports
In your test tree, Click on All Ports. For each port, uncheck Append Location to Port Name. Starting
at the top port, click on the Port Name Cell and rename the port to Network Control. Proceed down
the list and name the ports Real-Time Control, Best Effort, Over Subscribed Port 1 and Over
Subscribed Port 2.
5. Create Host Blocks
Right-Click on the All Ports Æ All Hosts. Click on Add Multiple Hosts.
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6. Host Block Port Selection
Select all the ports and then press Next.
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7. Select Protocols
The defaults are okay, press Next to continue.
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8. Select Encapsulation
Set the Upper Layer protocol to None and select Next to continue.
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9. Configure Hosts
Under Hosts per port, type “20,000”. Also, check Launch Traffic Wizard after generating Hosts and
then press Finish.
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10. Set Up Traffic
In following step, each of the three transmitting ports will transmit 50% load to each of the two
oversubscribed ports. In the Traffic Wizard, select all ports and press Next.
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11. Endpoint Configuration
Under Distribution, check backbone. Make sure Encapsulation is EthernetII. For the Source ports
select Network Control, Real-Time Control and Best Effort. Under Destination select Over
Subscribed Port 1 and Over Subscribed Port 2. Uncheck “Stream only generation”. Press Finish.
12. Set TX Port Rates
Under All Ports Æ All Traffic Generators find the Load column and set the first three ports to 100%
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13. Set QoS Policies
Under Tools, select Service Class Builder.
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14. Configuring Service Classes
Check the “+ Service Class” button three times. Name the top cell Network Control. Name the
second cell Real Time and the third cell Best Effort. Change Results View Mode to Histogram and
click on “+ Parameter” and Add Frame Loss, Out of Sequence and Max Latency.
Set the following values:
Frame Loss Out of Sequence Max Latency
Network
Control
0<=x<=0 0<=x<=0 0<=x<=7
Real-Time 0<=x<=1000 0<=x<=10 0<=x<=7
Best Effort 0<=x<=1844674407470955199 0<=x<=1844674407470955199 0<=x<=37580963
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15. Mapping Class
Choose the mapping tab, and Under Traffic Group click the Click Here hyperlink.
16. Configuring Traffic Groups
Under Traffic Group, type Service Class and click Add. Under Traffic Subgroup, add Network
Control, Real-Time, and Best Effort. Press OK once completed.
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17. Setting Traffic Groups
Under Traffic Group, select Network Control and under Service Class also select Network Control.
Press Add. Repeat for the remaining two Groups. Finally, press OK to continue with the test
configuration.
18. Bind QoS Profiles to Traffic
Under All Ports Æ All Stream Blocks, under name, rename the first Stream Block to Network
Control and rename remaining Stream Blocks accordingly.
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19. Setting Traffic Groups
Scroll to the right till the Traffic Group column is visible. Select the “…” button which appears
when selected.
20. Subgroup Selection
Use the Subgroup drop down menu and select the corresponding Subgroup. Press OK once
completed. Repeat steps 19 and 20 for Real-Time Control and Best Effort.
21. Add Automation across Frame Sizes
In the toolbar, select the Wizards button. Under Configuration Wizards Æ Sequence Generator, run
the Custom Test. Select Next to continue with the configuration.
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22. Configuration of Test
Click the Enable Preview checkbox. Under Test Type, pick Step. Set the duration to 360 seconds.
Under load, click Custom and type in 100. Under Frame size, check step with a Start of 64, Stop at
1518 and a Step of 64. Press Next once the configuration is completed.
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23. Optional Configuration
Under Optional Commands, check L2 Learning and check “Before Each Iteration”. Check “Save
detailed stream results with every iteration”. Press Finish.
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24. Run Test
In the Command Sequencer, press the Run button.
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25. Results Report
At the end of each first iteration, the Results Reporter will launch and populate results. After each
iteration, the new results will also be populated.
Analysis
26. Determining Pass or Fail
For each Frame Size Iteration in the Results Reporter, select the ServiceClassValidation template.
Next, click the Test Summary tab. Here you will see if each service class level passed or not.
Repeat for each frame size. When finished, it is possible to export the report to PDF or HTML.
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DUT
VLAN
Source
Congesting VLAN
Source
Best Effort
QoS High
QoS Medium
Oversubscribed
Port
Source Generation Domain QoS Impairment
Domain
QoS Analysis Domain
VLAN 802.1pq VLAN Remarking Validation
Associated RFCs
• IEEE 802.2
• IEEE 802.1p
• IEEE 802.1q
Spirent Communications Test Equipment Needed
• 3 Ethernet Ports, 10/100/1000 or 10 GigE
• Spirent TestCenter Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to validate that the Device Under Test (DUT) does not remark 802.1p or
802.1q bits under congestion. The expected behavior of this test is that sweeping across different frame
sizes will not result in the DUT remarking Virtual Local Area Network (VLAN) data.
Setup
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Step-by-Step
1. Configure DUT
On each port, configure VLAN VIDs from 2-4095, creating 4094 VLANs. Set up port trunking on
each port to perform VLAN to VLAN forwarding.
2. Cable DUT to Spirent TestCenter
Plug all three ports sequentially into three sequential Spirent TestCenter ports.
3. Reserve Ports on Spirent TestCenter
Launch Spirent TestCenter and reserve the required ports to perform the test.
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4. Rename Your Spirent TestCenter Ports
In your test tree select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, click on the Port Name Cell and rename the port to VLAN Primary. Proceed down the
list and name the ports VLAN Congestor, Measure Port.
5. Setup Traffic
In this step, the Primary VLAN port will send line rate traffic to the Measure Port and the VLAN
Congestor port will send 50% load across all VLANs. Each generating ports VLAN will send all 7
priority levels per VLAN. Select VLAN Primary Æ Traffic Generator.
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6. Adding a Raw Stream Block
Use the Add drop down menu and select Add a Raw Stream Block.
7. Naming the Stream Block
Name the Stream Block Primary VLAN, and click on the Frame tab.
8. Configuring the Frame
Right-click on the IPv4 Header and select Delete IPv4 Header.
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9. Destination MAC Modifier
Click on the Destination MAC Header and under Actions, click on Insert MAC Modifier.
10. Incrementing Destination MAC Addresses
Increment the Destination MAC with a count of 4094. Hit OK.
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11. Source MAC Modifier
Click on Source MAC, and under actions, click on Inset MAC Modifier.
12. Increment the MAC Source
Increment the MAC Source by 4093. Press OK.
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13. Inserting VLANs
Select the Ethernet II header, and under actions select Insert Vlans.
14. Configuring VLAN ID
Under the VLAN Header, set the ID to 2 and insert a Modifier.
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15. VID Modifier
Increment the VID by 4093. Select OK.
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16. Priority Modifier
Under VLAN Header click on the Priority bits. Insert a Modifier under Actions.
17. Priority Modifier Configuration
Increment the priority by 7 and press OK.
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18. Link Modifiers/VFDs
Under Actions, Select Link Modifiers/VFDs.
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19. Link Modifiers/VFDs Configuration
For each VID change the Source, Destination and Priority Fields using the drop down menus. Press
OK once configuration is completed.
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20. Stream Block Editor Finalization
No further changes need to be made to the frame. Press OK to return to the main window.
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21. Duplicating the Stream Block
Right-click on the Stream Block and select Copy.
22. Pasting Stream Block
Expand the VLAN Congestor port, select Traffic Generator, right-click in the grid and select “Paste
StreamBlock”. Change the name of the pasted StreamBlock to “Congestor VLAN”.
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23. Edit Frame
Select the Stream Block and hit Edit. Select the Frame tab and change the Source MAC address to
00:10:95:00:00:02. Press OK once completed.
24. Redo the Modifiers
For each Stream Block that was pasted, edit the Stream Block and redo each one of the modifiers
that was previously done.
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25. Measure Port Stream Block
Repeat the previous two steps with the Measure Port. Though, for this Stream Block, change the
Source MAC Address to 00:00:01:00:00:01.
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26. Port Rates
Select All Traffic Generators and change the Load value to 100 on VLAN Primary and 50 on VLAN
Congestor.
27. Add Automation across Frame Sizes
In the toolbar, select the Wizards button. Under Configuration Wizards Æ Sequence Generator, run
the Custom Test. Select Next to continue with the configuration.
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28. Configuration of Test
Click the Enable Preview checkbox. Under Test Type, pick Step. Set the duration to 360 seconds.
Under load, click Custom and type in 100. Under Frame size, check Step with a Start of 64, Stop at
1518 and a Step of 64. Press Next once the configuration is completed.
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29. Optional Configuration
Under Optional Commands, check L2 Learning and check “Before each iteration”. Check “Save
detailed stream results with every iteration”. Press Finish.
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30. Command Sequencer Edit
The Command Sequencer needs to quickly be edited and have another step added in. Select the
Edit Sequence button.
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31. Inserting the Commands
Insert a Wait Command as the very last entry in the Loop.
32. Grouping the Wait Command
Right-click on the Wait Command and select the Group Commands.
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33. Edit the Wait/Loop Command
Double-click on the Loop before the Wait and set the Looping Options to Continuous. Double-click
on the Wait and set the Time to 1 second.
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34. Setting up Template Filters
On the Measuring Port, expand the port branch and click on Traffic Analyzer.
35. Configuring Traffic Analyzer Frame
Right-click on the IPv4 header in the template, and delete the IPv4 Header.
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36. Adding VLANs to Traffic Analyzer Frame
Right-click on the EthernetII header and add a VLAN Header. Check the VLAN Priority and Priority
fields.
37. Results Browser View
In the Results Browser, change the view to Stream Results Æ Filtered Stream Results. Change the
Show: pull down to the Measure Port.
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38. Run Test
In the Command Sequencer, press the Run button. At the end of each frame size, the Command
sequencer will pause. To move to the next frame size, click the “Break out of Current Loop”.
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Analysis
39. Determining Pass or Fail
At the end of each frame size, the load of VLAN ID and priorities will be balanced by frame count.
The frame size will pass if each combination of VLAN ID and Priority are the same. The frame size
will fail if some VLAN and PRIORTY combinations have different values.
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DUT
VLAN
Source
Congesting VLAN
Source
Best Effort
QoS High
QoS Medium
Oversubscribed
Port
Source Generation Domain QoS Impairment
Domain
QoS Analysis Domain
VLAN 802.1q VLAN Remarking Validation
Associated RFCs
• IEEE 802.1q
Spirent Communications Test Equipment Needed
• 3 Ethernet Ports, 10/100/1000 or 10 GigE
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to validate that the Device Under Test (DUT) does not remark 802.1q under
congestion. The expected behavior of this test is that sweeping across different frame sizes will not result
in the DUT remarking VLAN data.
Setup
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Step-by-Step
1. Configure DUT
On each port, configure VLAN VIDs from 2-4095 for the outer tag and 2-4095 for the inner tag,
creating 4094
2
VLANs. Set up port trunking on each port to perform VLAN to VLAN forwarding.
2. Cable DUT to Spirent TestCenter
Plug all three ports sequentially into three sequential Spirent TestCenter ports.
3. Reserve Ports on Spirent TestCenter
Launch Spirent TestCenter and reserve the required ports to perform the test.
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4. Rename Your Spirent TestCenter Ports
In your test tree select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, click on the Port Name Cell and rename the port to VLAN Primary. Proceed down the
list and name the ports VLAN Congestor, Measure Port.
5. Setup Traffic
In this step, the Primary VLAN port will send line rate traffic to the Measure Port and the Congestor
VLAN port will send 50% load across all VLANs. Each generating ports VLAN will send all 7 priority
levels per VLAN. Select VLAN Primary Æ Traffic Generator.
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6. Adding a Raw Stream Block
Use the Add drop down menu and select Add a Raw Stream Block.
7. Naming the Stream Block
Name the Stream Block Primary VLAN, and click on the Frame tab.
8. Configuring the Frame
Right-click on the IPv4 Header and select Delete IPv4 Header.
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9. Destination MAC Modifier
Click on the Destination MAC Header and Under Actions, click on Insert MAC Modifier.
10. Incrementing Destination MAC Addresses
Increment the Destination MAC with a count of 4094. Press OK.
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11. Source MAC Modifier
Click on Source MAC, and under actions click on Insert MAC Modifier.
12. Increment the MAC Source
Increment the MAC Source by 4093. Select OK.
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13. Inserting VLANs
Select the Ethernet II header and under actions select Insert Vlans.
14. Configuring VLAN ID
Under the VLAN Header, set the ID to 2 and Insert a Modifier.
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15. VID Modifier
Increment the VID by 4093. Choose OK.
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16. Priority Modifier
Under VLAN Header, click on the Priority bits. Insert a Modifier under Actions.
17. Second VLAN
Right-click on the VLAN Header and insert a second level of VLAN. Repeat the above steps by
incrementing the VID and the Priority fields.
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18. Link Modifiers/VFDs
Under Actions, Select Link Modifiers/VFDs.
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19. Linking the Modifiers
For the outer VLAN ID (the first created VLAN), increment the Source and Destination MAC
addresses along with both Priority fields and the inner VLAN ID. Press OK once the configuration is
completed.
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20. Stream Block Editor Finalization
No further changes need to be made to the frame. Press OK to return to the main window.
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21. Duplicating the Stream Block
Right-click on the Stream Block and select Copy.
22. Pasting Stream Block
Expand the VLAN Congestor port, select Traffic Generator, right-click in the grid and select “Paste
the StreamBlock”. Change the name of the pasted Stream Block to “Congestor VLAN”.
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23. Edit Frame
Select the Stream Block and click on Edit. Select the Frame tab and change the Source MAC
address to 00:10:95:00:00:02. Press OK once completed.
24. Redo Modifiers
Edit each pasted Stream Block and redo the modifiers as required for each.
25. Measure Port Stream Block
Repeat the previous two steps with the Measure Port. Though, for this Stream Block, change the
Source MAC Address to 00:00:01:00:00:01.
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26. Port Rates
Select All Traffic Generators and change the Load value to 100 on VLAN Primary and 50 on VLAN
Congestor.
27. Add Automation across Frame Sizes
In the toolbar, select the Wizards button. Under Configuration Wizards Æ Sequence Generator, run
the Custom Test. Select Next to continue with the configuration.
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28. Configuration of Test
Click the Enable Preview checkbox. Under Test Type, pick Step. Set the duration to 360 seconds.
Under load, click Custom and type in 100. Under Frame size, check step with a Start of 64, Stop at
1518 and a Step of 64. Press Next once the configuration is completed.
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29. Optional Configuration
Under Optional Commands, check L2 Learning and check “Before each iteration”. Enable “Save
detailed stream results with every iteration”. Press Finish.
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30. Command Sequencer Edit
The Command Sequencer needs to quickly be edited and have another step added in. Select the
Edit Sequence button.
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31. Inserting the Commands
Insert a Wait Command as the very last entry in the Loop.
32. Grouping the Wait Command
Right-click on the Wait Command and select the Group Commands.
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33. Edit the Wait/Loop Command
Double click on the Loop before the Wait and set the Looping Options to Continuous. Double-click
on the Wait and set the Time to 1 second.
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34. Adding VLANs to Traffic Analyzer Frame
Right-click on the EthernetII header and add a VLAN Header. Check the VLAN Priority and Priority
fields.
35. Results Browser View
In the Results Browser, change the view to Stream Results Æ Filtered Stream Results. Change the
Show: pull down to the Measure Port.
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Analysis
36. Determining Pass or Fail
At the end of each frame size, the load of VLAN ID and priorities will be balanced by frame count.
The frame size will pass if each combination of VLAN ID and Priority are the same. The frame size
will fail some VLAN and PRIORTY combinations have different values.
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802.1q in a Mixed Tag Environment
Associated RFCs
• IEEE 802.2
• IEEE 802.1p
• IEEE 802.1q
Spirent Communications Test Equipment Needed
• 7 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test is to inspect the performance of 802.1p in a mixed tag environment. This test will
mix untagged, classic tagged and Q-in-Q traffic across the Device Under Test (DUT). The expectation is that
802.1p performance will be maintained even in mixed tagged environments.
Setup
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Step-by-Step
1. Configure DUT
Log in to your DUT, place the Mixed Tagged port and the Congestor port into Multiple Virtual
interfaces: untagged, VLAN 2-4095, Q-in-Q (2-4095, 2-4095). For the Mixed Tag port, place all
VLANs with a PRI value of 7. For the Congestor Port, place all PRI values to 0.
Plug all three ports sequentially into three sequential Spirent TestCenter ports.
2. Reserve Ports on Spirent TestCenter
Launch Spirent TestCenter and reserve the required ports to perform the test.
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3. Rename Your Spirent TestCenter Ports
In your test tree, select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, click on the Port Name Cell and rename the port to Mixed Tag Port. Proceed down the
list and name the ports VLAN Congestor, Measure Port.
4. Setting Up Traffic
Select Ports Æ Mixed Tag Port Æ Traffic Generator.
5. Adding Stream Block
Use the Add drop down menu and select Add Raw Stream Block.
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6. Frame Configuration
Remove the IPv4 Header.
7. Updating MAC Addresses
Change the Source EthernetII address to 01:00:01:00:00:01 and the destination address to
01:00:02:00:00:01. Click on the Source address and then select on Actions Æ Add MAC Modifier.
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8. Setting Increment
Set to increment with a value of 1000 and select OK. Perform the same action on Destination MAC.
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9. Main Frame Configuration Screen
Select OK once back to the “Stream Block Editor” window.
10. Naming the Stream
Change the name of the Stream to Untagged.
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11. Adding a Second Stream Block
Use the Add drop down menu and select “Add Raw Stream Block”.
12. Frame Configuration
Remove the IPv4 Header.
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13. Updating MAC Addresses
Change the Source EthernetII address to 02:00:01:00:00:01 and the destination address to
02:00:02:00:00:01. Click on the Source address and then click on Actions Æ Insert MAC Modifier.
14. Setting Modifier Increment
Set to increment with a value of 1000 and then press OK. Perform the same action on Destination
MAC.
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15. Adding VLANs
Right-click on the EthernetII header and add a VLAN tag.
16. Configuring VLAN ID
Under the VLAN Header, set the ID to 2 and insert a Modifier.
17. VID Modifier
Increment the VID by 4093. Press OK.
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18. VLAN Priority Field
Change the VLAN PRI field to 7.
19. Naming the Stream
Change the name of the Stream to Classic VLAN.
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20. Adding A Third Stream Block
Use the Add drop down menu and select “Add Raw Stream Block”.
21. Frame Configuration
Remove the IPv4 Header.
22. Updating MAC Addresses
Change the Source EthernetII address to 03:00:01:00:00:01 and the destination address to
03:00:02:00:00:01. Click on the Source address and then click on Actions Æ Insert MAC Modifier.
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23. Setting Modifier Increment
Set to increment with a value of 1000 and then press OK. Perform the same action on Destination
MAC.
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24. Adding VLANs
Right-click on the EthernetII header and add a VLAN tag.
25. Configuring VLAN ID
Under the VLAN Header, set the ID to 2 and insert a Modifier.
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26. VID Modifier
Increment the VID by 4093. Press OK.
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27. VLAN Priority Field
Change the VLAN PRI field to 7.
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28. Adding Second VLAN Header
Right-click again on the EthernetII header and add a Second VLAN Tag. Perform the same add
modifier steps to the second ID and change the PRI field to 7.
29. Renaming Stream Block
Change the name of the Stream to Q-in-Q VLAN.
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30. Copying Stream Blocks
Copy all three Stream Blocks by first selecting all three and then right-clicking and select “Copy
StreamBlock”.
31. Populate the Congestor Port
Use the navigation window and select Ports Æ Congestor Port Æ Traffic Generator.
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32. Pasting the Streams
Right-click on the grid and paste streams.
33. Editing the Stream Blocks
Edit each Stream Block and change the second byte from 00 to 01 on the Source EthernetII
Address field.
34. Naming Congestor Port Stream Blocks
For each Stream name, append the text “- Low Priority”.
35. Port Rates
Select All Traffic Generators and change the Load value for each port to 100.
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36. Changing Results Browser View
In the Results Browser, change a view to Stream Results Æ Detailed Stream Results. Change the
monitored port to Congested Port.
37. Add Automation across Frame Sizes
In the toolbar, select the Wizards button. Under Configuration Wizards Æ Sequence Generator, run
the Custom Test. Select Next to continue with the configuration.
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38. Setup Frame Size Automation
Change the Test Type to Step. Change the Duration to 120 Seconds. Under Load, click Custom and
change the field to 100. Under Frame size, choose Step enter a start value of 64 and a Stop value
of 9022. Set the Step to 64. Select Next.
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39. Optional Configuration
Under Optional Commands, check L2 Learning and “Before each iteration”. Be sure “Save detailed
stream results with every iteration” is checked. Select Finish.
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40. Test Results Viewing
While viewing Stream Results Æ Detailed Stream Results, scroll to the left and find Average
Latency. If you click on Basic Sequencing, you will see frame loss, in order, out of order and
reordered.
41. Run the Test
In the Command Sequencer, click on Run. While traffic is running you will be able to see real-time
results in the Results Browser.
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Validation
42. At the end of the test, Results Reporter will open with your post-test results. For each frame size,
expand the results tree to Stream Results Æ Detailed Stream Results.
The frame size will pass if untagged, classic VLAN and Q-in-Q VLAN have minimal loss (<0.1%) and
minimal maximum latency (<7 ms). You will notice that stream with X-Low Priority should have
nearly 100% loss.
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Testing Committed Information Rate (CIR) by Layer 2 Ethernet Port
Associated RFCs
• IEEE 802.2
Spirent Communications Test Equipment Needed
• 3 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test is to prove that the Committed Information Rate (CIR) by a Layer 2 source port can
be maintained in congested state. The expected behavior of this test is the Device Under Test (DUT) will
properly maintain a minimum information rate without resequencing, dropping or excessively delaying
packets.
Setup
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Step-by-Step
1. Configure DUT
Login to your DUT. Place all three ports in the same VLAN. Turn off all protocols except L2
forwarding and L2 QoS shaping. Configure Port 1 on the DUT as a CIR of 600 Mbps; configure Port
2 as a CIR of 300 Mbps; and, configure Port 3 as Best Effort Step 2 – Cable DUT to Spirent
TestCenter.
Plug all three ports sequentially into three sequential Spirent TestCenter ports.
2. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter GUI and reserve the required ports.
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3. Rename Your Spirent TestCenter Ports
In your test tree, click on All Ports. For each port, uncheck Append Location to Port Name. Starting
at the top port, click on the Port Name Cell and rename the port to “600 Mbps CIR”. Proceed down
the list and name the ports “300 Mbps CIR”, “Congestor Port”, “Over Subscribed Port” .
4. Create Host Blocks on transmitting and Over Subscribed Ports
Right-click on the All Ports Æ All Hosts. Click on Add Multiple Hosts.
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5. Port Selection
Select all the ports and then press Next.
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6. Protocol Selection
The defaults are okay, press Next to continue.
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7. Upper Layer Protocols
Set Upper Layer to None and then press Next.
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8. Hosts Configuration
Under Hosts per port, type “200,000”. Check Launch Traffic Wizard after generating Hosts and
then press Finish.
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9. Setup Traffic
Make sure all ports are selected and press Next.
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10. Endpoints Configuration
Change the Distribution to Backbone and Encapsulation to EthernetII. Uncheck “Stream only
generation”. Under Source, check the Host Blocks under 600 and 300 Mbps CIR and Congestor.
On the Destination, check Congested Port. Select Next.
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11. Frame Size and Load
Change the Frame Size to 64 Bytes and the Load to 100 percent. Press Finish once completed.
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12. Edit Host Layer 2 Addresses and Edit Traffic Generators
Under All Ports select All Hosts. Change the base EthernetII Source address of the 600 Mbps CIR to
“10:00:00:00:00:01”. Proceed to change the “300 Mbps CIR” source address to
“20:00:00:00:00:01” and the Congestor port address to “30:00:00:00:00:01”.
13. Port Speed
Select “All Traffic Generators” and scroll to the right and change the Load Units of all ports to
Mbps. Change the 600 Mbps CIR port to 600, 300 Mbps CIR port to 300 and the Congestor Port to
1000.
14. Perform Learning, Setup Receive Counters
Right-click on All Stream Blocks and select L2Learning Æ Start L2 Learning. Login to your DUT and
verify you have learned 600K unique MAC addresses.
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15. Results Browser
In your Results browser, change your subscription to Port Results Æ Detailed Port Results. Scroll to
the right until you see RX Bit Rate. Also, it is possible to verify the port is transmitting at the correct
rate. In the other Results Browser window, change the subscription to Stream Results Æ Detailed
Stream Results. Select the Advanced Sequencing tab and scroll to the right till Reorder Frame
Count to Dropped Frame Rate is visible.
16. Run Test
In the toolbar, select the Start Traffic on All Ports icon.
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Analysis
17. Determining Pass or Fail
In order to pass, each of the criteria below must be achieved:
• 600 Mbps CIR Port (MAC Address 01:00:00:00:00:01)
• RX Bit rate is at least 600 Mbps AND there are no lost, duplicated, late or reordered
frames.
• 300 Mbps CIR Port (MAC Address 02:00:00:00:00:01)
• RX Bit rate is at least 300 Mbps AND there are no lost, duplicated, late or reordered
frames.
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Layer 3 QoS Verification Testing
Introduction 129
DiffServ Code Point Remarking Detection 130
Edge DiffServ Remarking Validation 152
Verify QoS Over Classic VLAN 181
Verify QoS Over Q-in-Q VLAN 199
Verify Triple Play QoS 215
Verify DiffServ Customer SLA Over Carrier VPLS Network 254
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Introduction
Layer 3 QoS, or Quality of Service, is a set of technologies that allow the Device Under Test (DUT) to
differentiate traffic at the Layer 3 datagrams and forward across the domain of the network according to a
global policy.
By definition, QoS must have a common policy edge-to-edge in the network for the policy to maintain
coherence. QoS involves prioritization of network traffic. QoS can be targeted at a network interface, toward
performance of a given server or router, or in specific applications. A network monitoring system must
typically be deployed as part of QoS to insure networks are performing at the desired level. RFC 2474
defines how an IP TOS field should be marked based on service level.
When testing QoS on a DUT, it is important to realize that many protocols’ maximum allowable impairment
refers to the end-to-end sums of impairment. For example, 150 ms tends to be the upward allowable delay
before the codecs change to a lower quality codec. The 150 ms is the total budget which includes all
switches, routers and links. As a rule, one can calculate 1 ms of latency per 100 km of link. In addition, the
data packets will typically traverse according to these averages:
Hops to Number of Hops
Local Zone in City 2-4 hops
City POP 1-2 hops
Inter-regional POP 2-4 hops
Interstate WAN 2-3 hops
International WAN 2-3 hops
Thus for an Interstate Flow, the number of hops may be 12-15 hops, and for an International WAN the
number of hops may reach 20 hops.
When calculating the maximum allowable budget for metrics such as latency, take the maximum end-to-
end metric, and divide by the number of hops. Or, in the case of latency, first subtract 1 ms per 100 km,
then divide by the number of hops, giving you your local budget. Typical impairments measured in QoS are:
Maximum Latency, Sequencing Errors (Loss/Duplication/Reorder), Bandwidth and Latency Jitter.
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DUT
DiffServ Source
Best Effort
QoS High
QoS Medium
Remarked
Destination
Source Generation Domain QoS Impairment
Domain
QoS Analysis Domain
Best Effort
QoS High
QoS Medium
DiffServ Code Point Remarking Detection Test
Associated RFCs
• RFC 2475
Spirent Communications Test Equipment Needed
• 3 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective is to test for unexpected remarking of DiffServ Code Points across a Queuing FIB. The
expected behavior of the DUT is to not remark the DiffServ Code Points while under load and across
variable frame sizes.
Setup
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Step-by-Step
1. Configure DUT
Log into the DUT. Turn on DiffServ Code Point inspection and turn off Remarking. Configure the
port connected to “DiffServ Source” to an address of 10.0.0.1/16 and the port connected to
DiffServ Destination to 20.0.0.1/16. Turn on IP Forwarding.
2. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter and reserve the required ports.
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3. Rename Your Spirent TestCenter Ports
In your test tree, Click on All Ports. For each port, uncheck Append Location to Port Name. Starting
at the top port, click on the Port Name Cell and rename the port to “DiffServ Source”. Proceed
down the list and name the port “DiffServ Destination”.
4. Add Code Points to DiffServ Source
In the All Ports view, right-click and add Multiple Hosts.
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5. Port Selection
Select the DiffServ Source port and click on Next.
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6. Protocol Selection
The defaults are okay, press Next to continue.
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7. Upper Layer Protocols
Select the Upper Layer to be IPv4 and select Next.
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8. Host Configuration
Change the number of Hosts per port to 1. Set the IP Source Address to 10.0.1.10 and the Prefix
Length to be 16. Set the Gateway to be 10.0.0.1. Select Finish once configuration is finished.
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9. Host Name Configuration
Select on Port Æ DiffServ Source Æ Hosts in the navigation window.
10. Host Duplication
Right-click on the default and select duplicate.
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11. Duplication
Enter a value of 15 for the Number of copies. Press OK once completed. This will give a total of 16
hosts.
12. Update IPv4 Address
Select all rows and right-click on the IPv4 Address and Fill Increment using the x.x.1.x filter.
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13. Renaming Hosts
Starting with the first host, rename the host default and then select Edit Interface.
14. ToS Field Update
In the IPv4 header select the “…” in the ToS field.
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15. DiffServ Configuration
Choose DiffServ and under the code point pull down, pick default. Going from Host to Host,
change the name and code point using the following names and code points: AF11, AF12, AF13,
AF21, AF22, AF23, AF31, AF32, AF33, AF41, AF42, AF43, EF, CS6 and CS7.
16. Copying Hosts
Select All Hosts and right-click and copy the Hosts.
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17. Pasting Hosts
Open up DiffServ Destination port Æ Hosts and right-click and select paste.
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18. Changing IP Address
Cycle through all hosts and add 100 to the value in front of the Source IP address third octet. For
example, 10.0.1.10 becomes 10.0.101.10; and 10.0.11.10 becomes 10.0.111.10. Also, make
sure to rename the Hosts accordingly.
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19. Create Traffic Across the DUT
In the Toolbar, select the Wizards button. Open up Traffic Æ Traffic Wizard and then press Next.
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20. Port Selection
Select both ports and press Next.
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21. Stream Generation
Set the Distribution to Pair and the Encapsulation to IPv4. Under Source, select DiffServ Source Æ
AF11. Under Destination, Select DiffServ Destination Æ AF11. Press Add. Repeat for all code
points. Press Next once completed.
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22. Change the Port mode to Rate Based and the Load to 6.25. Check “Expand stream blocks under
ports” Æ “One path per streamblock” and press Finish.
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23. Renaming Stream Blocks
Click on DiffServ Source ÆTraffic Generator. From the top, rename the Stream Blocks: default,
AF11, AF12, AF13, AF21, AF22, AF23, AF31, AF32, AF33, AF41, AF42, AF43, EF, CS6 and CS7.
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24. Enable ARP/ND
In the test case tree, click on Settings. Select the ARP/ND tab. And check the last box, “Enable
ARP/ND Before Transmission”.
25. Setup the Analyzer and Burst Count
On the DiffServ Destination port, select the Traffic Analyzer. Expand the IPv4 header and check the
ToS Header.
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26. Results Browser
In the Results Browser, change the subscription of right browser to Stream Results Æ Filtered
Stream Results. Set the Monitored port to DiffServ Destination.
27. Scheduling Mode
On the DiffServ Source Port, select the Traffic Generator. Set the Scheduling Mode to Port Based,
set the Duration Mode to Bursts, set Burst Size to 15; finally, set Burst(s) to 100.
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28. Run Test
To run the test, perform the following actions:
Loop through the following “DiffServ Source” Burst(s) count: 100, 1000, 10000 and 100000.
Right-click on the Filtered Stream Results Browser Æ Clear all Results Views.
Set the “DiffServ Source” Burst(s) accordingly.
Press Apply.
In the toolbar, select “Start Traffic”.
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29. Examining the Views
At the end of the burst, examine the filtered stream views. The counts should be symmetric,
meaning that each ToS Value should be the same. Counts where one value is below the burst
count and another value is above the burst count indicates the code point was incorrectly altered
from the below burst count value to the above burst count value.
Analyze Results
The test passes if there is no variance in ToS values, and when all values equal the burst size. The DUT fails
if it incorrectly remarks values at any burst size.
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DUT
DiffServ Source
Best Effort
QoS High
QoS Medium
Remarked
Destination
Source Generation Domain QoS Impairment
Domain
QoS Analysis Domain
Best Effort
QoS High
QoS Medium
Edge DiffServ Remarking Validation Test
Associated RFCs
• RFC 2475
Spirent Communications Test Equipment Needed
• 3 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to determine if the Device Under Test (DUT) is properly remarking the TOS
byte in the IPv4 and IPv6 headers. The expected behavior is that each and every packet that mates the
remarking policy will be properly remarked.
Setup
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Step-by-Step
1. Configure DUT
Log in to the DUT. Configure the East port as the stub facing port with an address of 10.0.0.1 /16
and 2001::1/64. Configure the West port as the core facing port with an address of 20.0.0.1 and
2002::1/64. Turn on DiffServ remarking from the stub to the core side across the DUT.
Use the following table:
Protocol Dest Port Code point
TCP 80 EF – A0h
TCP 53 AF11 – 28h
TCP 25 AF41 – 88h
UDP 4004 AF32 – 70h
UDP 0 AF13 – 38h
2. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter and reserve the required ports.
3.
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Rename Your Spirent TestCenter Ports
In your test tree, select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, click on the Port Name Cell and rename the port to East. Proceed down the list and
name the port West.
4. Setup Traffic on East Port
Under Ports>East Æ Traffic Generator, click on the Add button and select add a Raw Stream Block.
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5. Frame Type Selection
Under Frame Size, click on iMIX and select the “JMIX Upstream” profile. Select the Frame tab.
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6. Source MAC Modifier
Select the Source MAC, and then select Add MAC Modifier.
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7. Increment Count
Increment the MAC Modifier by a count of 200,000.
8. IPv4 Source
Select the IPv4 Æ IP Source field and enter in an IP of 10.0.0.2. Next, select Insert IPv4 Modifier.
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9. Increment IP Source
Increment the IP Source by 65000.
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10. Add UDP Header
Click the Actions Æ Add Header. Under the IP category, add a UDP header.
11. Changing UDP Header Modifier
Expand the UDP header; click on the Destination Port field; and, click Actions “Insert Modifier”.
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12. UDP Modifier
Click on List and in the Value field, type “0, 4004”. Press OK, and press OK again.
13. Stream Block Name
Rename the Stream Block to “IPv4-UDP”.
14. Duplicating Stream
Right-click on the IPv4-UDP Stream Block, and select Duplicate.
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15. Duplicate
Duplicate the Stream by 1, and press OK.
16. Rename Stream
Rename the new Stream ”IPv4-TCP”.
17. Edit Stream Block
Click on the IPv4-TCP stream, and press Edit in the tool bar.
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18. Editing Frame
Select the frame tab. Right-click on the UDP header and select Delete UDP Header.
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19. Adding TCP Header
Click Actions Æ Add Header and add a TCP header under the IP category.
20. TCP Header Modifier
Click on the TCP Æ Destination Port field, and click Actions Æ Insert Modifier.
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21. Configure TCP Modifier
Click on List and under Value, type “80,53,25”.
22. Adding More Traffic To The East Port
Again, select the Add button and add a Raw Stream Block.
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23. Frame Type Selection
Under Frame Size, click on iMIX and select the JMIX Upstream profile. Next, select the Frame tab.
24. Modifier on Source MAC Address
Select the Source MAC, and then select the Add MAC Modifier.
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25. Increment MAC Modifier
Increment the MAC Modifier by a count of “20000”.
26. Remove IPv4 Header
Right-click on the IPv4 header, and select Delete IPv4 Header.
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27. Insert IPv6 Header
Click Actions Æ Add Header and insert an IPv6 header.
28. IPv6 Source Field
Select on the IPv6 Source field. Type in 2001:: and then select Insert IPv6 Modifier.
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29. IPv6 Source Modifier
Increment the IP Source by 65000.
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30. Adding UDP Header
Select Actions Æ Add Header. Under the IP category, add a UDP header.
31. UDP Modifier
Expand the UDP header, and select the Destination Port field. Next, select Actions Æ Insert
Modifier.
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32. UDP Modifier Configuration
Select List, and in the Value field enter 0, 4004. Press OK, then OK again.
33. Stream Naming
Rename the Stream Block to IPv6-UDP.
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34. Stream Duplication
Right-click on the IPv6 – UDP Stream Block and select Duplicate.
35. Duplicate
Duplicate the Stream by 1, and press OK.
36. Stream Naming
Rename the new Stream to IPv6-TCP.
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37. Stream Block Edit
Select the IPv6-TCP stream, and select Edit in the tool bar.
38. Frame Edit
Select the frame tab. Right-click on the UDP header, and select Delete UDP Header.
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39. Add TCP Header
Click Actions Æ Add Header and add a TCP header under the IP category.
40. TCP Destination Port
Select the TCP Æ Destination Port field, and select Actions Æ Insert Modifier.
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41. Edit Modifier
Click on List, and under Value enter in a value of 80, 53, 25.
42. Copy the Stream Blocks
Under Ports Æ East Æ Traffic Generator, select all Stream Blocks and right-click and copy.
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43. West Port Traffic
Go to the Ports Æ West Æ Traffic Generator and paste the Stream Blocks.
44. Edit West Port Stream Blocks
For each Stream Block, select the Stream Block and then press Edit. Reverse the IP Source and
Destination and MAC Source and Destination fields.
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45. Setup the Analyzer and Burst Count
On the West port select the Traffic Analyzer. Expand the IPv4 header and check the ToS Field.
46. Add UDP Header
Click Actions Æ Add Header and add a UDP Header.
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47. UDP Analyzer
Expand the UDP header and click on UDP Æ Destination Port.
48. Results Browser
In the Results Browser, change the subscription of right browser to Stream Results Æ Filtered
Stream Results. Set the Monitored port to West.
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49. Scheduling Mode
On the East Port, click on Traffic Generator. Set the Scheduling Mode to Port Based, Set the
Duration Mode to Bursts. Set Burst Size to 15. Set Burst(s) to 100.
50. ARP/ND Enable
In the test case tree, click on Settings. Select the ARP/ND tab. And check the last box, Enable
ARP/ND Before Transmission.
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51. Run Test
To run the test, perform the following Actions:
Loop through the following East Source Burst(s) count: 100, 1000, 10000, 100000.
Right-Click on the Filtered Stream Results Browser Æ Clear all Results Views.
Set the East Source Burst(s) Accordingly.
Press Apply.
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In the toolbar, select “Start Traffic”.
At the end of traffic, look at the filtered results. Each Destination Port Number should have exactly
one DiffServ Code point, and each code point should have exactly one UDP Dest Port. If this is
true, then UDP for IPv4 passed.
Record the results.
Repeat Steps 45-47 by changing the L4 header to TCP and clicking on TCP destination port and
repeating both tests with an IPv6 Filter.
Analyze Results
If all 4 cases have a 1 to 1 mapping of destination port to code point, then the tests passes, else fails.
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Verify QoS over Classic VLAN
Associated RFC/Standard
• RFC 2475
• IEEE 802.1p
Spirent Communications Test Equipment Needed
• 2 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test is to see how flows shaped at different DiffServ code points react while embedded
in classic VLANs. The expected behavior is that VLAN-tagged traffic will have no effect on flow quality.
Flow Code Point
Max Seq. Errors
(%)
Max Latency Max Jitter
Flow 1/VLAN 1-254 AF-43 1.0% 7 ms +/- 0.1 ms
Flow 2/VLAN 1000-1254 EF 0.1% 7 ms +/- 0.3 ms
Flow 3/VLAN 2000-2254 AF-31 1.5% 10 ms +/- 0.7 ms
Flow 4/VLAN 3000-3254 AF-32 1.0% 10 ms +/- 0.7 ms
Background/Untagged 00 Any Any Any
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VLAN X
VLAN X
VLAN Y VLAN Y
VLAN Z
VLAN Z
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
DUT
Setup
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Step-by-Step
1. Configure DUT
Log into the DUT. Configure 4095 VLANs. Start with VLAN 1 and assign a default gateway of
10.0.1.1/24. For VLAN 2, assign 10.0.2.1/24 for all 4095 VLANS. As the third octet fills up, use the
second octet, all in a sequential fashion. Each VLAN will receive a /24 subnet. Perform the same
actions on the West port, but change the first octet to 20.
2. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter GUI and reserve the required ports to perform the test.
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3. Rename Your Spirent TestCenter Ports
In your test tree, click on All Ports. For each port, uncheck Append Location to Port Name. Starting
at the top port, click on the Port Name Cell and rename the port to East. Proceed down the list and
name the port West.
4. Setup Hosts
Right-click on All Ports Æ All Hosts and select Add Multiple Hosts.
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5. Port Selection
Select both ports and press Next.
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6. Protocol Selection
The defaults are okay, press Next to continue with the configuration.
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7. Encapsulation
Change Upper Layer to IPv4 and in the Lower Layer section enable Number of VLAN Headers. The
default value of 1 is okay for Number of VLAN Headers. Finally press Next to continue.
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8. VLAN Configuration
In “Total VLANs per port” change the value to 4095. Also, change the VLAN ID field to 1 and verify
that “Repeat across ports” is selected. Press Next to continue.
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9. Host Configuration
For the Hosts per VLAN, select 252. Under the IPv4 section, change the IPv4 Address to 10.0.1.2,
netmask to /24 and the gateway to 10.0.1.1. In the “Step” field, select the “…” button.
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10. Step Configuration
Verify the “Step per host” is set to 0.0.0.1. Check and change the “Step per port” to 10.0.0.0.
Check and change the “Step per VLAN #1” to 0.0.1.0. Press OK.
11. Host Configuration
Check the Launch Traffic Wizard after generating hosts and press Finish.
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12. Port Selection
In the Traffic Wizard, select both ports and press Next.
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13. Endpoints
Change Distribution to Pair and Encapsulation to IPv4. Under Source, select the East check box,
which will select all the created Hosts. Repeat this for Destination using the West port. Press Add
to include all port pairings and select Next.
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14. Frame Size and Load
Name the Stream Block as Traffic and change the Frame Size to iMIX/TCPv4. Change the
Scheduling mode to Rate Based. Uncheck “Expand stream blocks under ports”. Enable “Vary
Protocol and QoS” at the top of the window, and then press the Configure button.
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15. DiffServe Code Points
Select the QoS tab and select the DiffServ radio button. Add the DiffServ code points in the table
above. Select OK. Press Finish and then Apply.
16. Frame Size and Load
Once back to the Frame Size and Load configuration screen, press Finish.
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17. Setup Analyzer on West Port
On Ports Æ West Æ Traffic Analyzer, select Template Filter.
18. Add VLAN
Right-click on the EthernetII header and select Insert Vlans.
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19. IPv4 ToS/DiffServ Enable
Expand the IPv4 header and click the filter checkbox for ToS/DiffServ.
20. Results Browser
In the right Results Browser, change the view to Stream Results Æ Filtered Stream Results. Change
the Show: pull down menu to the West port.
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21. ARP/ND Enable
Under Settings Æ ARP/ND enable the Enable ARP/ND Before Transmission checkbox.
22. Run the Test
In the tool bar, click the Start Traffic on all ports. Run the test for several hours. As variant of this
test, on the All Ports Æ All Stream Blocks, select a stream and use the slider in the tool bar to
reduce and expand the rate of an individual stream (Sum of stream <=100 Load) on the fly.
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Analysis
23. Analysis
While Traffic is running, select the Stream Results Æ Filtered Stream Results view. Select the
Advanced Sequencing tab and look for out of sequence, lost, duplicated or late frames on any
code point.
Select the Histograms (Sequence Run Length), and look for noticeable differences in the run
length.
Click on Basic Counters, and look at min, average and maximum latencies that which should be
very close within the same code point and have a wider spread as the code point moves to best
effort.
Compare measured results with the results in the above table to determine pass or fail of this test
case.
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Verify QoS over Q-in-Q VLAN
Associated RFCs/Documents
• RFC 2475
• IEEE 802.1p
Spirent Communications Test Equipment Needed
• 2 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test is to see how flows shaped at different DiffServ code points react embedded in
classic VLANs. The expected behavior is that VLAN-tagged traffic will have no effect on flow quality.
Code Point Max Seq. Errors (%) Max Latency Max Jitter
AF-43 1% 7 ms +/- 0.1 ms
EF 0.1% 7 ms +/- 0.3 ms
AF-31 1.5% 10 ms +/- 0.7 ms
AF-32 1.0% 10 ms +/- 0.7 ms
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VLAN X,Y
Best Effort
QoS High
QoS Medium
VLAN Q-in-Q
Configured
DUT
VLAN X,Y
VLAN X,Z
VLAN X,Z
VLAN A,B
VLAN B,C
VLAN A,B
VLAN B,C
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Setup
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Step-by-Step
1. Configure DUT
Log into the DUT. Configure 252 x 120 VLANs (each outer tag has 128 inner tags). Configure the
DUT to use 252 outer VLANs and 128 inner VLANs. Assign the outer VLANs with an IP address of
10.0.x.1/24, starting with X=0 till X=251. Repeat this step for the inner VLAN (VLAN 2) but use the
IP address 10.x.2.1/24, starting with X=1 till x=128. Make sure each VLAN receives a 128 subnet.
Repeat this step on the West port but use a first octet of 20.
2. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter and reserve the required ports.
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3. Rename Your Spirent TestCenter Ports
In your test tree, select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, select the Port Name cell and rename the port to East. Proceed down the list and
name the port West.
4. Adding Hosts
Right-click on All Ports Æ Hosts and select Add Multiple Hosts.
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5. Port Selection
Select both ports and then press Next.
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6. Protocol Selection
The defaults are okay, press OK to continue.
7. Adding VLANs
Change the Upper Layer to IPv4 and enable Lower Layer Æ Number of VLAN Headers. Set this
value to 2 and press Next.
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8. VLAN Configuration
In the VLANs per Port #1, select 252 and on VLANs per port #2, select 128. Change the VLAN ID
field to 1 and verify that “Repeat across ports” is selected as well as for Vlan #2. Select Next.
9. Host Configuration
On the Hosts per VLAN, select 252. Under the IPv4 section, change the IPv4 Address to 10.0.1.2,
“Prefix length” to 24 and the gateway to 10.0.1.1. On the Step field select the “…” button.
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10. Address Step
Verify the Step per host is set to 0.0.0.1. Check and change the Step per port to 10.0.0.0. Check
and change the Step per VLAN #1 to 0.0.1.0 and VLAN #2 to 0.1.0.0. Press OK.
11. Hosts Traffic Wizard
Enable the “Launch Traffic Wizard after generating hosts” and press Finish.
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12. Traffic Wizard Ports
In the Traffic Wizard, select both ports and press Next.
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13. Endpoint Selection
Change Distribution to Pair and Encapsulation to IPv4. Under Source and Destination, select all
the East Æ Host as the source and West Æ Host as the destination. Press Add to add the pairings
and press Next to continue.
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14. Optional Configuration
Name the Stream Block as Traffic and change the Frame Size to iMix Æ TCPv4. Change the
“Scheduling mode” to Rate Based. Uncheck “Expand Stream Blocks under ports”. Check “Vary
Protocol & QoS” at the top right and then select Configure.
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15. DiffServ Code Point Configuration
Select the QoS tab and then select the DiffServ radio button. Add the DiffServ code points in the
table above and press OK.
16. Frame Configuration
No further changes are required, press Finish.
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17. Setup Analyzer on West Port
On Ports Æ West Æ Traffic Analyzer. The Template Filter screen will appear.
18. Insert VLAN Header
Right-click on the EthernetII header and add a VLAN.
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19. Enable ToS/DiffServ
Expand the IPv4 header and enable the filter checkbox for ToS/DiffServ.
20. Results Browser
In the right Results Browser, change the subscription to Stream Results Æ Filtered Stream
Results. Change the Show: pull down to the West port.
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21. Enable ARP/ND
Under Settings Æ ARP/ND select the “Enable ARP/ND Before Transmission” checkbox at the
bottom right.
22. Run the Test
In the tool bar, click the Start Traffic on all ports. Run the test for several hours. As variant of this
test, on the All Ports Æ All Stream Block, select a stream and use the slider in the tool bar to
reduce and expand the rate of an individual stream (Sum of stream <= 100 Load) on the fly.
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Analysis
23. Analysis
While Traffic is running, select the Stream Results Æ Filtered Stream Results view. Select the
Advanced Sequencing tab, and look for out of sequence, lost, duplicated or late frames on any
code point.
Select the Histograms (Sequence Run Length), and look for noticeable differences in the run
length.
Click on Basic, and look at min, average, and maximum latencies that should be very close within
the same code point and have a wider spread as the code point moves to best effort.
Compare measured results with the results in the above table to determine pass or fail of this test
case.
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Verify Triple Play QoS
Associated RFCs
• RFC 2475
Spirent Communications Test Equipment Needed
• 3 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to simulate traffic with similar network attributes to MPEG-2 TS Video, SIP
G.729 Encoded Voice, HTTP 1.0 and FTP with Different QoS DiffServ code points and test to verify that under
different bursting conditions, QoS is maintained.
Flow
Code Point
Max Sequencing
Errors (%)
Max Latency Max Jitter
MPEG-2 TS AF-43 1.0% 7 ms +/- 0.1 ms
G.729 SIP Voice EF 0.1% 7 ms +/- 0.3 ms
HTTP AF-31 1.5% 10 ms +/- 0.7 ms
FTP AF-32 1.0% 10 ms +/- 0.7 ms
Background 00 Any Any Any
Setup
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Step-by-Steps
1. Configure DUT
Log in to the DUT. Configure the East port as the stub facing port with an address of 10.0.0.1/16.
Configure the West port as the core facing port with an address of 20.0.0.1. Turn on DiffServ
remarking from the stub to the core side across the DUT. Use the table shown above.
2. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter and reserve the required ports to perform the test.
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3. Rename Your Spirent TestCenter Ports
In your test tree, click on All Ports. For each port, uncheck Append Location to Port Name. Starting
at the top port, click on the Port Name Cell and rename the port to East. Proceed down the list and
name the port West.
4. Setup Video Traffic on East Port for 50 MPEG-2 TS Streams
On Ports Æ East Æ Traffic Generator, change the scheduling mode to Priority Based.
5. Adding Stream Block
Select Add Æ Add Raw Stream Block.
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6. Stream Name
Name the Stream MPEG-2 TS I-Frame. Change the Settings Æ Burst Size to 1. Change the Load
Options Percent to 100 Mbps. Change the Frame Size to 1380. Select the Frame tab.
7. Source MAC Modifier
Select the MAC Source and then select Actions Æ Add MAC Modifier.
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8. Increment the Modifier
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
9. IPv4 Source Modifier
Select the IP Source Address, and change the value to 10.0.0.2. Next, select the Add IP Modifier.
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10. Modifier Increment
Increment the value by 50 and press OK.
11. IPv4 Destination Address Modifier
Repeat the previous two steps, except change the Destination Address to 20.0.0.2.
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12. ToS Field
Select IPv4 Æ ToS field and select the “…” button.
13. DiffServ Code Point
Select the DiffServ radio button and then use the drop down menu to select AF-43 as a code point.
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14. Adding a Header
Right-click on the IPv4 header and select Add Header.
15. UDP Header
Select the UDP Header and press OK.
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16. Destination Port
Expand the UDP Header and change the Destination UDP Port number to 1234, press OK.
17. Duplicate Stream
Right-click on the previous Raw Stream and select duplicate.
18. Duplication
Duplicate the stream 1 time.
19. Stream Rename
Name the Stream MPEG-2 TS B & P-Frames.
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20. Edit Stream
Select the Edit button to make changes to the new stream. Change Settings Æ Burst Size to 5 and
update the Load Options Percent to 400 Mbps. Finally, change the Frame Size to 576 and press
OK.
21. Setup Voice Traffic on the East Port for 50 G.729 SIP Voice calls
On the Ports Æ East Æ Traffic Generator select the Add button again and choose Add Raw Stream
Block.
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22. Stream Name and Other Options
Name the Stream Block G.729 SIP VoIP. Change the rate to 860 Kbps. Change Setting Æ Priority to
1. Select the Frame tab.
23. Create New Frame
Select Frames Æ Create new Frame Æ Create new Frame.
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24. New Frame Selection
Select the Advanced Radio Button and under Category:IP, select “G729Ipv4Frame” and press OK.
25. MAC Source Modifier
Select the Frame tab and select the MAC Source. Next, select Actions Æ Add MAC Modifier.
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26. Modifier Increment
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
27. IPv4 Address Changes
Select the IP Source Address, and change the value to 10.0.0.200. Select Add IP Modifier.
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28. IPv4 Modifier Increment
Increment the value by 50 and press OK.
29. IPv4 Destination Address
Repeat the previous two steps to the IPv4 Destination Address, except change the Destination
Address to 20.0.0.200.
30. IPv4 ToS Field
Select the button which appears in the IPv4 Æ ToS field.
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31. DiffServ Code Point
Select the DiffServ radio button. Using the drop down menu, select EF as a code point.
32. Adding the UDP Header
Right-click on the IPv4 header and select Add Header.
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33. UDP Header
Select the UDP Header and press OK.
34. Update Destination Port
Expand the UDP Header and change the Destination UDP Port number to 5000 and press OK.
35. Setup HTTP Traffic
Again, select Add Æ Raw Stream Block.
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36. Stream Name and Other Options
Name the Stream Block “HTTP Traffic”. Change the Frame Size to 512. Change the rate to 5 Mbps.
Change Setting Æ Priority to 2. Change the Settings Æ Burst size to 15 and the “Inter-frame gap”
to 24. Click on the Frame tab.
37. Create New Frame
Select Frames Æ Create new Frame, then select “Create new Frame”.
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38. TCP Frame
Select the Advanced Radio Button and under Category:Basic, select “Tcp over IPv4” and then
press OK.
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39. Source MAC Modifier
Select the MAC Source and then select Actions Æ Add MAC Modifier.
40. Modifier Increment
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
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41. IPv4 Source Address
Select on the IPv4 Source Address, and change the value to 10.0.50.200. Next, select the Add IP
Modifier.
42. IPv4 Modifier Increment
Increment the value by 50 and press OK.
43. IPv4 Destination Address
Repeat the previous two steps for the IPv4 Destination Address, except change the Destination
Address to 20.0.50.200.
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44. ToS Field
Select the button which appears in the ToS field.
45. DiffServ Value
Select the DiffServ radio button. Using the drop down menu, select AF-31 as a code point.
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46. TCP Port Configuration
Expand the TCP Header and change the Destination TCP Port number to 80 and press OK.
47. Custom Header
Right-click on the TCP header and select Add Header.
48. Select Custom Header
Locate Custom and press OK.
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49. Configuring Custom Header
Expand the custom header and type in “47 45 54 1 2F 70 61 74 68 2F 74 6F 2F
66 69 6C 65 2F 69 6E 64 65 78 2E 68 74 6D 6C 1 48 54 54 50 2F 31
2E 30”. Press OK once completed.
Hint: It is also possible to copy the above hex string and paste it into the byte pattern field by
using the Ctrl + v key stroke.
50. Setup FTP Traffic
Again, select Add Æ Add Raw Stream Block.
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51. FTP Stream Configuration
Name the Stream Block FTP Traffic. Change the Frame Size to 1518. Change the rate to (3 Mbps x
50) 150 Mbps. Change Setting, Priority to 3. Change the Settings Æ Burst size to 1. Select the
Frame tab.
52. Create New Frame
Select Frames Æ “Create new Frame”, then select Create new Frame again.
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53. Adding TCP
Click on the Advanced Radio Button and under Category:Basic select “Tcp over IPv4”, press OK.
54. Source MAC Modifier
Select the Frame tab and then select the MAC Source. Click on Actions Æ Add MAC Modifier.
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55. Modifier Increment
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
56. IPv4 Source Address
Select the IP Source Address, and change the value to 10.0.100.200. Next, select Add IP Modifier.
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57. IPv4 Modifier Increment
Increment the value by 50 and press OK. Repeat the same steps for the Destination Address,
except change the IP to 20.0.100.200.
58. ToS Field
Select the IPv4 Æ ToS field and then press the button which appears.
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59. DiffServ Code Point
Select the DiffServ radio button and then use the drop down menu to select AF-32 as a code point.
60. TCP Header
Expand the TCP Header and change the Destination TCP Port number to 21 and press OK.
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61. Setup Best Effort Traffic
Again, select Add Æ Add Raw Stream Block.
62. Best Effort Configuration
Name the Stream Block “Best Effort”. Change the Frame Size to 768. Change the rate to 300 Mbps.
Change Setting, Priority to 4. Change the Settings Æ Burst size to 1. Select the Frame tab.
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63. Add Header
Select Add Header.
64. Add UDP Header
Under the Category:IP locate the UDP header and press OK.
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65. Source MAC Modifier
Select the MAC Source and then select Actions Æ Add MAC Modifier.
66. Increment the Modifier
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
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67. IPv4 Source Modification
Click on the IP Source Address, and change the value to 10.0.200.200. Select the Add IP Modifier
option.
68. IPv4 Modifier Increment
Increment the value by 50 and press OK. Perform the same action on the Destination Address,
except change the IP address to 20.0.200.200.
69. ToS Field
Select the IPv4 Æ ToS field and then select the button which appears.
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70. DiffServ Code Point Selection
Select the DiffServ radio button and the use the drop down menu to select Default as a code point.
71. UDP Header Configuration
Expand the UDP header, and select the Destination Port. Next, select Actions Æ Insert Modifier.
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72. Random Modifier
Select Type Æ Random. Select OK twice.
73. Setup the West Port
On Ports Æ East Æ Traffic Generator, select all streams; right-click and select Copy Stream Block.
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74. Paste Stream Blocks
On Ports Æ West Æ Traffic Generator, right-click and select “Paste StreamBlock”.
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75. Edit Stream Blocks
For each Stream Block, press the Edit button and then in the new window select the Frame tab.
Reverse the MAC Source and Destination Fields. Reverse the IP Source and Destination Fields.
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76. Enable ARP
Under Project Æ Setting Æ ARP/ND, select “Enable Cyclic ARP” and Enable ARP/ND Before
Transmission.
77. Setup the DUT
Log into the DUT. From the table above, turn on Strict Priority Queuing based on DiffServ value
between the East and West ports. Set up all necessary IP Addresses and IP Forwarding.
78. Setup the Analyzer
On the Ports Æ West Æ Traffic Analyzer, check the IPv4 Æ ToS field.
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79. Histogram Configuration
On West Æ Traffic Analyzer Æ Histogram tab, change the histogram mode to “Sequence Run
Length”.
80. Results Browser Setup
In the right Results Browser, change the counter subscription to Stream Results Æ Filtered Stream
Results.
81. Run the Test
In the tool bar, click the Start Traffic on all ports. Run the test for several hours. As variant of this
test, on the All Ports Æ All Stream Block, select a stream and use the slider in the tool bar to
reduce and expand the rate of an individual stream (Sum of stream <=100 Load) on the fly.
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Analysis
82. Analysis
While Traffic is running, select the Stream Results Æ Filtered Stream Results view. Select the
Advanced Sequencing tab, and look for out of sequence, lost, duplicated or late frames on any
code point.
Select the Histograms (Sequence Run Length), and look for noticeable differences in the run
length.
Click on Basic and look at min, average, and maximum latencies, which should be very close
within the same code point and have a wider spread as the code point moves to Best Effort.
Compare measured results with the results in the above table to determine pass or fail of this test
case.
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VPLS Core
Best Effort
QoS High
QoS Medium
VPLS
Configured
DUT
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
CE
P
CE
P
P P
CE
CE
CE
CE
CE
CE
Verify DiffServ Customer SLA Over a Carrier VPLS Network
Associated RFCs
• RFC 2475
Spirent Communications Test Equipment Needed
• 3 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to verify that Customer DiffServ QoS is properly maintained within VPLS
tunnels across a carrier-grade network. This tests case assumes the Device Under Test (DUT) will maintain
QoS policies interior to VPLS tunnels. QoS levels tested and their passing behaviors are:
Flow (%) Code Point
Max Sequencing
Errors
Max Latency Max Jitter
MPEG-2 TS AF-43 1.0% 7 ms +/- 0.1 ms
G.729 SIP Voice EF 0.1% 7 ms +/- 0.3 ms
HTTP AF-31 1.5% 10 ms +/- 0.7 ms
FTP AF-32 1.0% 10 ms +/- 0.7 ms
Background 00 Any Any Any
Setup
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Step-by-Step
1. Configure the DUT
Login to the DUT and configure three ports, LAN, Branch1 and Branch2. Give each port the
following configuration:
Port DUT IP Role
Sub-
Interfaces
Starting Sub-
Interface
LAN 10.0.0.1/24 LAN Facing 2000
10.0.1.1 /
Incrementing
mask 0.1.1.0
Branch1 20.0.0.1/24 Core Facing 1000
20.0.1.1 /
Incrementing
mask 0.1.1.0
Branch2 30.0.0.1/24 Core Facing 1000
30.0.1.1 /
Incrementing
mask 0.1.1.0
Configure the DUT for OSPF and place all ports into Area 0.0.0.0. Turn on VPLS and configure 1000
VPLS tunnels between LAN Å Æ Branch1 and LAN Å Æ Branch2. Turn on QoS DiffServ Processing
for all tunnels.
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2. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter and reserve the require ports to complete this test.
3. Rename Your Spirent TestCenter Ports
In your test tree, select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, select on the Port Name cell and rename the port to LAN, Branch1 and Branch2.
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4. Technology Selector Selection
In the toolbar, press the Technology Selector button.
5. VPLS Selection
Under VPN, select VPLS/VPWS L2VPN (LDP) and press OK.
6. Configuration Wizard
In the toolbar, select the Wizards button.
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7. Wizard Selection
Select the Configuration Wizards Æ Routing Æ VPN Æ LDP VPLS wizard.
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8. Configure DUT to Core
Be sure to enable “Use core side ports” and check Branch 1 and Branch 2 ports. Check the Sub-
Interfaces on both Branch 1 and Branch 2, set the Sub-Interface Count to 1000. Set the Branch1
DUT IPv4 address to 20.0.1.1, the DUT IPv4 Address Step to 0.1.1.0 and the netmask to /24. Set
the Branch2 DUT IPv4 address to 30.0.1.1, the DUT IPv4 Address Step to 0.1.1.0 and the netmask
to /24.
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9. Configure Core Ports
Next, verify the “Enable P routers” checkbox is enabled and change the “# P routers per port/sub-
interface” to 5. Press Next to continue with the configuration.
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10. Customer Side Ports
Now verify the “Use customer side ports” checkbox is enabled, activate the LAN port and then
enable sub-interfaces. Change the Sub-Interface Count value to 2000. Press Next.
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11. VLAN Count
Change the number of VPNs to 2000. Press Next to continue.
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12. VPN Host Configuration
The defaults are okay, press Next to continue.
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13. VPN Traffic
Choose Customer Å Core and change the “Load % from Core Ports” to 51, press Finish.
14. Edit Streams
Go to All Ports Æ All Stream Blocks and select the first Stream Block. Press the Edit button.
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15. IPv4 Header
Select the Frame tab and expand the IPv4 header. Select the ToS field and then select Actions Æ
Insert Modifier.
16. Modifier Editing
Select the List option and Under Value, type: 00, 28, 30, 32 and 38. Press OK twice.
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17. Start the Routers
In the toolbar press the Start All Routers button and then press the Start All Traffic button.
18. Setup the Analyzer
On Ports Æ LAN Æ Traffic Analyzer, enable the IPv4 Æ ToS field.
19. Histogram Mode
Select the Histogram tab and change the Histogram Mode to “Sequence Run Length”.
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20. Results Browser
In the right Results Browser, change the counter subscription to Stream Results Æ Filtered Stream
Results. Using the Show: drop down menu, select the LAN port.
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Analysis
21. Analysis of Results
While Traffic is running, select Stream Results Æ Filtered Stream Results view. Then select the
Advanced Sequencing tab. Look for out of sequence, lost, duplicated or late frames on any code
point.
Next, select the Histograms (Sequence Run Length), and look for noticeable differences in the run
length.
Select the Basic tab and look at min, average and maximum latencies that should be very close
within the same code point and have a wider spread as the code point moves to best effort.
Compare measured results with the results in the above table to determine pass or fail of this test
case.
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Layer 3 QoS Control Plane Verification
Introduction 270
Verify DiffServ Strict Priority Queuing 271
Verify Weighted Random Early Detection in a DiffServ Network 288
Verify DiffServ QoS Stability Over BGP Route Failover 304
Verify DiffServ QoS Over LACP 337
Verify DiffServ QoS Stability Over RSVP TE Tunnel 381
Verify DiffServ QoS Stability Over Route Redistribution 400
Verify the Weighted Far Queuing (WFQ) QoS Algorithm 419
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Introduction
QoS queuing algorithms allow for network equipment to properly implement QoS policies. QoS queuing
algorithms are best tested with Spirent TestCenter because this platform correctly generates traffic patterns
to properly execute the edge case of the queuing algorithm. In addition, Spirent TestCenter™ provides a
strong analysis and debugging system.
Protocols such as WRED and WFQ are popular queuing algorithms used. This module will show the user
how to test whether the algorithm is working correctly. Weighted Random Early Detection (WRED) is a
queue management algorithm with congestion avoidance capabilities. WRED is an extension to Random
Early Detection (RED) where different queues may have different buffer occupation thresholds before
random dropping starts. There also may be different dropping probabilities, with packets classified into
these queues according to priority information as IP precedence or DSCP (for DiffServ).
QoS differentiation is now possible: Packets in queues with higher buffer occupation thresholds or lower
dropping probabilities are effectively prioritized.
WFQ is a generalization of Fair Queuing (FQ). For both WFQ and FQ, each data flow has a separate FIFO
queue. In FQ, with a link data rate of R, at any given time the N active data flows (the ones with non-empty
queues) are serviced simultaneously, each at an average data rate of R/N.
Since each data flow has its own queue, an ill-behaved flow (that has sent larger packets or more packets
per second than the others since becoming active) will only punish itself and not other sessions.
This section will allow the user to measure and test the effects of differentiated services over routing events
such as a routed failover. In addition, this section offers examples for BGP, RSVP-TE, OSPF, Route
Redistribution and LACP.
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Verify DiffServ Based Strict Priority Queuing Test
Associated RFCs
• RFC 2475
Spirent Communications Test Equipment Needed
• 2 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test is to validate that strict priority queuing functions of the Device Under Test (DUT)
are properly queuing traffic based on DiffSev Code Points in a mixed IPv4 environment. The expected
behavior of traffic is that packets from a traffic stream will receive queue priority over lower priority traffic
and will give way to higher priority traffic.
Setup
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Step-by-Step
1. Configure DUT
Log in to the DUT. Configure the East port as the stub facing port with an address of 10.0.0.1/16.
Configure the West port as the core facing port with an address of 20.0.0.1. Turn on DiffServ
remarking from the stub to the core side across the DUT.
Use the following table:
Protocol Dest Port Code point Scheduling Priority Load % Frame Size
TCP 80 EF – A0h 0 12% 78
TCP 53 AF11 – 28h 1 17% 90
TCP 25 AF41 – 88h 2 10% 1500
UDP 4004 AF32 – 70h 3 20% 78
UDP 0 AF13 – 38h 4 41% 1500
2. Reserve Ports on Spirent TestCenter
Launch Spirent TestCenter and reserve the required ports.
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3. Rename Your Spirent TestCenter Ports
In your test tree, click on All Ports. For each port, uncheck Append Location to Port Name. Starting
at the top port, click on the Port Name Cell and rename the port as East. Proceed down the list and
name the port West.
4. Setup Traffic on East Port
Select Ports Æ East Æ Traffic Generator branch and change the scheduling mode to Priority Base.
5. Add Raw Stream Block
Select the Add button and choose “Add Raw Stream Block”.
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6. Scheduling Priority
Change the Settings Æ Scheduling Priority to the value listed in the above table and then select
the Frame tab.
7. Destination MAC Modifier
Expand the EthernetII Header and select the Destination MAC address. Next, select Actions Æ
Insert MAC Modifier link.
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8. Modifier Count
Change Details Æ Count to 65000 and select OK.
9. Source MAC Modifier
Repeat the previous two steps, except perform the actions on the Source MAC address.
10. IPv4 Header Modifications
Expand the IPv4 Header and select Source Address. Change this value to 10.0.0.2 and select
Actions Æ Insert IPv4 Modifier.
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11. IPv4 Source Modifier Count
Change the Details Æ Count to 65000 and select OK.
12. IPv4 Destination Modifier
Select the IPv4 Æ Destination Address. Change the value to 20.0.0.2 then select Actions Æ Insert
IPv4 Modifier.
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13. IPv4 Destination Modifier Count
Change the Details Æ Count to 65000 and then Select OK.
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14. ToS Field
Select the IPv4 Header Æ ToS Field. Change the value as required from the table above.
15. Optional Headers
Right-click on the IPv4 Header and select Add Header.
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16. Add Correct Header
Add the correct header type from the table above (TCP or UDP in the IP Category).
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17. Destination Port
Expand the L4 header and click on the Destination Port. Change the value as looked up in the
table above and press OK.
18. Renaming the Stream Block
Rename the Stream Block name to “{UDP|TCP}-{DiffServ Code Point}-{Dest. Port Number}”.
Example: TCP-EF-80.
19. Repeat Steps
Repeat steps 5-18 for each row in the table above.
Note: If you right-click on an existing Stream Block, you can copy-and-paste a copy, and edit the
copy. The only values that change are the IP TOS, L4 Header Type and L4 Destination Port.
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20. Copy Stream Blocks
When all rows are added, select all the rows and right-click to copy all rows to the clipboard.
21. Add Traffic to the West Port
Under Ports West Æ Traffic Generator, paste your streams.
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22. Edit Stream Blocks
For each stream, select the Edit button and switch the Source MAC with the Destination MAC. Also,
switch the Source IP and the Destination IP.
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23. ARP/ND Enabled
Under Spirent TestCenter ÆSettings Æ ARP/ND, select the last box Enable ARP/ND Before
Transmission and the box Enable Cyclic ARP/ND. Check the box rate (packets per second), send as
fast as possible.
24. Setup the DUT
Log into the DUT. From the table above, turn on Strict Priority Queuing based on DiffServ value
between the East and West ports.
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25. Set the Traffic Load and Frame Size
On the All Ports Æ Stream Block tab, scroll to the right for each stream block; change the Frame
Length Mode value in the table above. Change the load to the percentage above.
26. Setup the Analyzer
Select Ports Æ West Æ Traffic Analyzer. In the Traffic Analyzer, check the IPv4 Æ ToS field.
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27. Change Result View
In the left Results Browser, change the view to Stream Results Æ Filtered Stream Results.
28. Changing Histogram Mode
On the West Æ Traffic Analyzer Æ Histogram tab, change the histogram mode to Sequence Run
Length.
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29. Run the Test
In the tool bar, click the Start Traffic on all ports. Run the test for several hours. As variant of this
test, on the All Ports Æ All Stream Block, select a stream and use the slider in the tool bar to
reduce and expand the rate of an individual stream (Sum of stream <=100 Load) on the fly.
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Analysis
30. Analysis
While traffic is running, select the Stream Results Æ Filtered Stream Results view. Select the
Advanced Sequencing tab, and look for out of sequence, lost, duplicated or late frames on any
code point.
Click on the Histograms (Sequence Run Length), and look for noticeable differences in the run
length.
Click on Basic Counters and look at min, average and maximum latencies that should be very
close within the same code point and have a wider spread as the code point moves to best effort.
If the code point experiences any sequencing errors such as loss, late or duplicated then the test
fails since the traffic is presented to the DUT in a pre-shaped strict priority queue order. In
addition, excessive latency at higher priorities would also indicate the DUT cannot queue real-time
traffic correctly.
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Verify Weighted Random Early Detection in a DiffServ Network
Associated RFCs/Documents
• RFC 2475
• Floyd, S., and Jacobson, V., Random Early Detection gateways for Congestion Avoidance V.1
N.4, August 1993, p. 397-413. Abstract.
Spirent Communications Test Equipment Needed
• 1 CPU-5000A High Performance Application Test Module (Using 3 Ports)
• Spirent TestCenter™ Chassis
• Spirent TestCenter L4-7 Software Module
• Miscellaneous Cables
Objective
The objective of this test is to verify the correctness of the Weighted Random Early Detection (WRED)
queuing algorithm in a Differentiated Services-based network. The expected behavior of this test is to
verify that the goodput of FTP over TCP will be selectively tuned down on lower priorities first.
Setup
WRED
Enabled DUT
FTP Server Pool
FTP Client
FTP Client
FTP Client
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Step-by-Step
1. Setup Your Device Under Test (DUT)
Login to your DUT. Configure three ports: Generation Port, with an IP Address of 10.0.0.1/16;
Congesting Port, with an IP Address of 20.0.0.1/16; and, Measured Port that has an IP Address of
30.0.0.1/16. Turn on IP Forwarding. Configure WRED on the Measured Port.
2. Reserving Ports
Launch the Spirent TestCenter L4-7 Application. Under Administration Æ Spirent TestCenter
Chassis, select Equipment Æ Add Chassis. Type in the IP Address of your Spirent TestCenter
chassis and press OK. On your CPU-5000A Module, reserve the first two ports (Generating Port and
Congesting Port) and the 5
th
port (Measured Port). Select Provision Æ Perform and then choose
Provision Æ Save Provision Data. Finally, select OK.
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3. Project Setup
Select File Æ New Æ Project. Set the Project Name to “three_code_point_WRED” and press Finish.
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4. Setting up New Test
In the projects tree, right-click the “three_code_point_WRED” project and select New Test.
5. Project Selection
Select the “three_code_point_WRED” project and press Next.
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6. Test Name
Change the test name to three_code_point_ WRED and press Next.
7. Test Category
Select “Device – Avalanche emulates both clients and servers” as the category of test to create.
Press Next.
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8. Specific Test Type
Select Advanced as the test type and press Finish.
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9. Adding Client Ports
On the Client tab, select the Ports sub-tab and then select the Add Multiple Ports Button. In the
window which appears, select the first two ports.
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10. Adding Server Ports
On the Server tab, select the Ports sub-tab. Click Add Port and select the fifth port. Click File Æ
Save All.
11. Setup the FTP Server Pool
On the Server Tab, select the Network sub-tab. Change the TCP Parameters Æ Inactivity timer to
20,000 ms.
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12. FTP Profile
On the Server tab, select the Profiles sub-tab. Next to the Default pull down, select the add new
Profile button. Set the name to “FTP_Assured_Forwarding_High”.
13. Server Configuration
Under the Description, type “FTP – Assured Forwarding High”. Change the Type to FTP. Change the
Connection Properties Æ ToS (Hex) to 38.
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14. Copy Profile
Next to the Profile Create button, select the Copy button. Change the name to “FTP-Assured
Forwarding Medium”. Change the ToS (hex) field to 30. Repeat this process again, except change
the name to “FTP-Assured Forwarding Low” and change the ToS (hex) field to 28.
.
15. Configuring Subnets
Select Server Æ Subnets and change the Subnet Name to FTP. Next, update the Netmask to /16
and the Network to 30.0.0.0. Select the Default Gateway, and in the Default Gateway field, type
30.0.0.1.
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16. Adding Associations
On the Server Æ Association Tab, add 4 associations. Under Profile, click and change each cell
from the top down: “Best Effort”, ”FTP – Assured Forwarding High”, ”FTP – Assured Forwarding
Medium”, ”FTP – Assured Forwarding Low”. For each profile, check the Default gateway checkbox
and Randomize IP checkbox. Type in the following Server IPv4 Address Range:
Profile IP Address (Range) Gateway Address
Best Effort 30.0.4.2-30.0.252.252 30.0.0.1
FTP – Assured Forwarding High 30.0.1.2-30.0.1.252 30.0.0.1
FTP – Assured Forwarding Medium 30.0.2.2-30.0.2.252 30.0.0.1
FTP – Assured Forwarding Low 30.0.3.2-30.0.3.252 30.0.0.1
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17. Setup Client Subnets
On the Client Æ Subnet Tab, select and delete the Default subnet and then add 4 subnets. Change
the Attributes of each row to:
Profile IP Address (Range) Netmask
Gateway
Address
Best Effort
10.0.4.2 --
30.0.4.100
/16 20.0.0.1
FTP – Assured Forwarding
High
10.0.1.2 --
30.0.1.100
/16 30.0.0.1
FTP – Assured Forwarding
Medium
10.0.2.2 --
30.0.2.100
/16 30.0.0.1
FTP – Assured Forwarding
Low
10.0.3.2 --
30.0.3.100
/16 30.0.0.1
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18. Setup Client Action Lists
On the Client Æ Actions tab delete the default and create 4 action lists with the following
attributes:
Best Effort
Action List:
IPSETTINGHEADER TOS=00
ASSIGN VARIABLE <forth UNIFORM 2 252>
1 ftp://30.0.4.<APPLY forth>/1g
Action List:
IPSETTINGHEADER TOS=38
ASSIGN VARIABLE <forth UNIFORM 2 252>
1 ftp://30.0.1.<APPLY forth>/1g
FTP – Assured Forwarding Medium
Action List:
IPSETTINGHEADER TOS=30
ASSIGN VARIABLE <forth UNIFORM 2 252>
1 ftp://30.0.2.<APPLY forth>/1g
FTP – Assured Forwarding Low
Action List:
IPSETTINGHEADER TOS=28
ASSIGN VARIABLE <forth UNIFORM 2 252>
1 ftp://30.0.3.<APPLY forth>/1g
FTP – Assured Forwarding High
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19. Setting Up the Action Lists
On the Client Loads tab, select the Rename button and name the Loading Profile Best Effort. Under
the Phase Editor, select the left green arrow and change the phase to Phase 0. Change the Steady
time to 5 seconds. Change the Label to Dormant. Click the right green arrow three times to edit
Phase 3. Change the Steady time to 400 seconds.
Copy the Load Profile by selecting the Copy button. Name the Profile AF_Low_ToS_28. Change the
Phase to 0 and change the Steady time to 55 seconds.
Copy the Load Profile by selecting the Copy button. Name the Profile AF_Med_ToS_30. Change the
Phase to 0 and change the Steady time to 155 seconds.
Copy the Load Profile by selecting the Copy button. Name the Profile AF_High_ToS_38. Change the
Phase to 0 and change the Steady time to 205 seconds.
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20. Setting up the Client Association
On the Client Æ Associations tab, enable “User Based” next to Load Profile Type.
Add 4 associations. For each row, click each cell and adjust the load, actions, Port (Best Effort
should go on Port 2, all others on Port 1) and Subnet. You will see a loading image graph at the
bottom.
21. Running the Test and Analyze the Results
On the Run tab, change the sampling interval to 1 second. In the tool bar, click run.
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-200
0
200
400
600
800
1000
1200
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36
High Priority Traffic
(WRED Allows most
Tarffic)
Medium Priority Tarffic
(WRED will throughtel
Traffic when Congested)
Best Effort Traffic
(WRED will start to Drop
Tarffic Early)
Analysis
22. After the test finishes, select the results tab and chose the test results row for the last test. Select
the Client Real-time Æ View tab.
Under each user profile (representing different DiffServ levels), look for the Goodput FTP Current
Receive rate. Copy this column and paste each column into a spreadsheet where columns
represent DiffServ Levels and Rows represent seconds. Each cell represents the goodput for that
code point/second.
Moving from the top, start to compare goodput values. If WRED is working, the goodput of higher
quality marked traffic should always be equal to or higher than lower quality marked traffic, but
not higher than higher marked traffic. The best way to see this is to graph the data on a 3D line
chart. On the other hand, if the goodput of a high quality flow is ever lower than a lower quality
flow – except in the case where all flows have a goodput of 0 (Full Buffer Saturation) – then WRED
has failed.
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Verify DiffServ QoS Stability Over BGP Route Failover
Associated RFCs
• RFC 2475
Spirent Communications Test Equipment Needed
• 3 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to verify proper DiffServ Stability over a BGP Route Failover. QoS levels
tested and their passing behaviors are:
Flow
Code
Point
Max Seq Errors
%
Max Latency Max Jitter
Rate
Mbps
Frame Size
MPEG-2 TS AF-43 1.0% 7 ms +/- 0.1 ms 300 1380
G.729 SIP
Voice
EF 0.1% 7 ms +/- 0.3 ms 100 128
HTTP AF-31 1.5% 10 ms +/- 0.7 ms 300 128
FTP AF-32 1.0% 10 ms +/- 0.7 ms 100 1500
Background 00 Any Any Any 200 576
Setup
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Step-by-Step
1. Configure the DUT
Login to the Device Under Test (DUT) and configure 3 ports: Injector Port, Primary BGP Route and
Secondary BGP Route. Assign the IP Addresses of 10.0.0.1/16 to the Injector Port; 20.0.0.1/16 to
the Primary BGP Route; and, 30.0.0.1 to the Secondary BGP Route Ports.
Configure iBGP on all three ports with the following attributes:
DUT Port DUT AS DUT RouteID Emulated AS
Emulated
RouteID
AS Path
10.0.0.1 AS 10 10.0.0.1 AS 11 10.0.0.2 1000
20.0.0.1 AS 10 20.0.0.1 AS 11 20.0.0.2 1001
30.0.0.1 AS 10 30.0.0.1 AS 11 30.0.0.1 2001,1001
2. Reserve Ports on Spirent TestCenter
Launch the Spirent TestCenter and reserve the required ports to perform this test.
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3. Rename Your Spirent TestCenter Ports
In your test tree, select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, click on the Port Name Cell and rename the port to Injector Port, Primary BGP Route
and Secondary BPG Route.
4. Traffic Selector
On the toolbar, select the Traffic Selector and enable BGP. Press OK.
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5. Add Multiple Routers
Under All Routers, right-click and select Add Multiple Routers.
6. Port Selection
Next, select all ports and press Next.
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7. BGP Enable
Enable BGP and press Next.
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8. Encapsulation
The defaults are okay, press Next to continue.
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9. Router Configuration
In the box to the right of “Routers per port” type in 1; under Router Æ Router ID, enable “Use IPv4
address as router ID”. Under IPv4 Æ IP Address, enter 10.0.0.2 with a “Prefix length” of 16.
Finally, in the IPv4 Æ Step section, press the “…” button.
10. Configure Stepping
Change the “Step per port” to 10.0.0.0 and press OK.
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11. Traffic Wizard Enable
Enable the “Launch Traffic Wizard after generating routers” and finally press Next.
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12. Configure BGP
Under DUT IPv4, enter IP address of 10.0.0.1. Under Step, select the “…” button and enable the
“Step per port” and enter in 10.0.0.0. Under AS, enter a value of 11 and select the “…” button and
enable the “Step per port” and enter in a value of 10. Under DUT AS, enter a value of 10 and press
Finish.
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13. Route Generator
Under Select Routers, uncheck Secondary BGP Route and press Next.
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14. IPv4 Route Configuration
Under Total Number of Routes to create, type in 1,000,000 (depending on your hardware this
value can be changed) with no duplicates. Click the “Prevent route aggregation by assigning non-
sequential routes to ports”. Change the Prefix length destitution type to Internet. Change the
primary path to 1000 and press Finish.
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15. Traffic Wizard Port Selection
In the Traffic Wizard screen, uncheck the Secondary BGP Route port and press Next.
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16. Port Pairing
Under Distribution, select Pair with an encapsulation of IPv4. Uncheck “Stream only Generation”.
Under Source and Destination Æ Source, select Router 1; for the Destination, select Router 2.
Press the Add button to add each pairing. Finally, press Next to continue with the configuration.
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17. MPLS Binding
The defaults are okay, press Next to continue.
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18. Stream Configuration
Rename the Stream Block to “MPEG2-TS ToS AF 43” and under Frame Size change the fix size to
1380. Change the Load unit to Mbps and the load to 300 Mbps. Under Generators Æ “Scheduling
mode” select Priority Based. Then under Settings Æ “Burst size” change the burst size to 20.
Uncheck “Expand stream block under ports”. Finally, enable Vary Protocol and QoS and select
Configure.
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19. Configure QoS
Select the QoS and then select the DiffServ radio button. Use the “DSCP Diffserv Codepoint” Name
drop down menu and choose AF43, press Add and OK.
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20. Frame Configuration
Press Next to continue with the setup.
21. Adding UDP Header
Right-click on the IPv4 Header and select Add Header.
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22. Choosing UDP
Under the IP Category, select UDP. Press OK.
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23. Frame Configuration
Press the Finish button.
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24. BGP Tab
Select the Primary BGP Route Æ Routers Æ BGP tab.
25. Edit Routes
Select the Edit Routes button.
26. Editing the AS Path
Scroll to the right and find the AS Path column. On the first cell, select the “…” button.
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27. Changing AS Path
Select the 21 AS Path and press Delete. Once the AS Path has been deleted, press OK.
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28. Changing All AS Paths
Select all Route Blocks and then right-click on the AS Path column and select Copy Down. Press
Close once completed.
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29. Setup Remaining Traffic
For each of the rows in the DiffServ Table Above, run the Wizards Æ Traffic Wizard. Select All
Routes on the Injector Port and pair the traffic to the Primary BGP Route routes as with the MPEG
Traffic. Be sure to uncheck the Stream Only Generation check box and “Expand All Streams per
port” check boxes. Set the load, frame size and DiffServ Code Point according to the table above.
Also, make sure to set the correct header in the frame. Do not overwrite the existing configuration
either, as you will lose all previously created Stream Blocks.
30. Copying Routes
Select Primary BGP Route Æ Routers Æ BGP tab. Select the Edit Routes button.
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31. Copy Routes
Select all the routes. Next, right-click and select “Copy BgpIpv4RouteConfig”.
32. Secondary BGP Route port
Select the Secondary BGP Route Æ Routers Æ BGP tab. Select the Edit Routes button.
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33. Route Population
Right-click and select “Paste BgpIpv4RouteConfig”.
34. AS Path Editing
Scroll to the right and find the column titled AS Path. Click on the “…” button from the first route
block AS Path.
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35. Adding an AS Path
Select the Add button to add in the new AS Path.
36. Changing the AS Value
Change the value from 1 to 2001 and press OK.
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37. Updating All AS Paths
Select all the Route Blocks, and right-click on the AS Path column. Select the Copy Down option
and then press close.
38. Setup the Analyzer
On the Primary BGP Route Æ Traffic Analyzer, expand the IPv4 header and enable the ToS field.
Perform the same action on the Secondary BGP Route port.
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39. Results Browser
In the Results Browser, select Stream Æ Filtered Stream and change the port to Primary BGP
Route.
40. Creating a Chart
Scroll to the right and locate the Short Term Average Latency. Select all rows except 00 (Best
Effort), and right-click on the Short Term Average Latency Column. Select “Add to Chart”.
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41. New Folder
Create a new folder called QoS Performance.
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42. Add Chart
Add a Chart to this folder called Latency Stability and press OK. Change the Port to Secondary BGP
Route and repeat this step adding code points to the graph. In this case, do not create a new
graph but append the Latency Stability Graph.
Repeat this step for the following metrics, each step creating a new chart: Advanced Sequencing
Æ Dropped, Advanced Sequencing Æ Late Frames and Advanced Sequencing Æ Reordered
Frames.
Change the right Results Browser to the Latency Stability chart, and the left Results Browser to the
Dropped Frames chart. Select Apply.
43. Start the Test
In the toolbar, select the Start Routers button. Let BGP start and converge. This step will also
advertise each ports BGP database. Because the primary BGP port as a shorter AS path, traffic will
flow from the Injector port to the Primary BGP Route port.
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44. ARP/ND
Once converged, Select Project Æ Settings Æ ARP/ND and enable the Enable ARP/ND Before
Transmission checkbox.
45. Start the Traffic
In the Toolbar, select the Start All Traffic button.
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46. QoS Goals Achieved
On the chart, establish the Primary BGP Route is able to achieve the QoS goals from the chart
above.
47. Route Withdraw
On the Primary BGP Route Æ Routers Æ BGP, right-click on the router and select BGP Æ Withdraw
Routes to withdraw all routes.
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Analysis
48. Look on the charts in the Results Browser. You will see the BGP route withdraw event. Examine
how long on the Secondary BGP Route port it takes for ToS levels to converge to the quality levels
mentioned above.
In order to pass, convergence should take no more then a few seconds after all BGP routes are
withdrawn on the BGP Primary port, as demonstrated by changing the Results Browser to Routing
Protocols Æ BGP Results.
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Verify DiffServ QoS Stability over LACP
Associated RFCs
• RFC 2475
Spirent Communications Test Equipment Needed
• 4 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to verify DiffServ QoS is maintained over LACP bundle. This test contains
two parts: verification over a stable LACP bundle and QoS Stability on LACP bundle change. QoS levels
tested and their passing behaviors are:
Flow Point Code
Max Sequencing Errors
(%)
Max
Latency
Max Jitter
MPEG-2 TS AF-43 1.0% 7 ms +/- 0.1 ms
G.729 SIP
Voice
EF 0.1% 7 ms +/- 0.3 ms
HTTP AF-31 1.5% 10 ms +/- 0.7 ms
FTP AF-32 1.0% 10 ms +/- 0.7 ms
Background 00 Any Any Any
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Best Effort
QoS High
QoS Medium
LACP
Configured
DUT
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Actor
LACP Bundle
Actor
LACP Bundle
LACP Bundle LACP Bundle
Actor
Actor
Actor
Actor
Actor
Actor
Setup
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Step-by-Step
1. Configure the DUT
Login to the Device Under Test (DUT) and configure 4 ports. Name the ports Bundle1, Bundle2,
Bundle3 and Measured Port. Place Bundles 1-3 into a LACP bundle. Give the bundle the virtual IP
Address of 10.0.0.1/16. Give the Measured Port an address of 20.0.0.1/16.
2. Reserve Ports on Spirent TestCenter
Launch Spirent TestCenter and reserve the require ports to perform the test.
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3. Rename Your Spirent TestCenter Ports
In your test tree, click on All Ports. For each port, uncheck Append Location to Port Name. Starting
at the top port, click on the Port Name Cell and rename the port to Bundle1, Bundle2, Bundle3 and
Measured Port. Choose Apply.
4. Setup Video Traffic on for 50 MPEG-2 TS Streams
On Ports Æ Bundle1 Æ Traffic Generator, change the scheduling mode to “Priority Based”. Repeat
this step for the other two bundle ports.
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5. Add Raw Stream Block
On Ports Æ Bundle 1 Æ Traffic Generator select Add Æ Add Raw Stream Block.
6. Stream Options
Name the Stream “MPEG-2 TS I-Frame”. Change the Settings Æ Burst Size to 1. Change the Load
Options Percent to 100 Mbps. Change the Frame Size to 1380. Select the Frame tab.
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7. Insert MAC Modifier
Select the MAC Source and then select Actions Æ Add MAC Modifier.
8. MAC Source Increment
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
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9. IPv4 Configuration
Select the IP Source Address, and change the value to 10.0.0.2 and select Insert IPv4 Modifier.
10. IPv4 Modifier Increment
Increment the value by 50 and press OK. Repeat the process for the Destination Address except
use the IP Address of 20.0.0.2.
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11. ToS Field
Select the IPv4 Æ ToS field and then press the “…” that appears.
12. DiffServ Code Point
Select the DiffServ radio button and use the drop down menu to select AF-43 as a code point.
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13. Adding a Header
Right-click on the IPv4 header and select Add Header.
14. UDP Header
Locate and select the UDP Header and then press OK.
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15. UDP Port
Expand the UDP Header and change the Destination UDP Port number to 1024 (it should be set by
default), and press OK.
16. Duplicate Stream
Right-click on the previously created Raw Stream and select Duplicate.
17. Duplicate Value
Duplicate the stream 1 time.
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18. Edit the Stream
Press the Edit button and rename the stream “MPEG-2 TS B & P-Frames”. Next, change Settings Æ
Burst Size to 5. Change the Load Options to 500 Mbps. Change the Frame Size to 576 and press
OK.
19. Setup Voice Traffic for 50 G.729 SIP Voice calls
On the Ports Æ Bundle1 Æ Traffic Generator, select Add and then select Add Raw Stream Block.
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20. Steam Configuration
Name the Stream Block G.729 SIP VoIP. Change the rate to 860 Kbps. Change Setting, Priority to
1. Click on the Frame tab.
21. Create New Frame
Select Frames Æ Create new Frame then “Create new Frame”.
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22. Selecting New Frame
Select the Advanced Radio Button and under Category:IP, select G.729Ipv4Frame and press OK.
23. MAC Modifier
Select the MAC Source and then select Actions Æ Add MAC Modifier.
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24. MAC Modifier Increment
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
25. IPv4 Configuration
Select the IP Source Address and change the value to 10.0.0.200. Next, select Insert IPv4 Modifier.
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26. Modifier Increment
Increment the value by 50, and press OK. Repeat the above process with the Destination Address
except use 20.0.0.200 as the IP.
27. ToS Field
Select the IPv4 Æ ToS field and select then select the “…” button that appears.
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28. DiffServ Code Point
Select the DiffServ Radio button and then use the drop down menu to select EF as a code point.
29. Add UDP Header
Right-click on the IPv4 header and select Add Header.
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30. Adding UDP Header
Locate and select the UDP Header. Press OK once completed.
31. UDP Port
Expand the UDP Header and change the Destination UDP Port number to 5000, and press OK.
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32. Setup HTTP Traffic
Again, select Add Æ Add Raw Stream Block.
33. Stream Name and Other Options
Name the Stream Block “HTTP Traffic”. Change the Frame Size to 512. Change the rate to 5 Mbps.
Change Setting Æ Priority to 2. Change the Settings Æ Burst size to 15 and the Inter-frame gap to
24. Click on the Frame tab.
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34. Create New Frame
Select Frames Æ Create new Frame, then choose “Create new Frame”.
35. TCP Frame
Select the Advanced Radio Button and under Category:Basic, select “Tcp over IPv4” and then
press OK.
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36. Source MAC Modifier
Select the MAC Source and then select Actions Æ Add MAC Modifier.
37. Modifier Increment
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
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38. IPv4 Source Address
Select on the IPv4 Source Address, and change the value to 10.0.50.200. Next, select Insert IPv4
Modifier.
39. IPv4 Modifier Increment
Increment the value by 50 and press OK.
40. IPv4 Destination Address
Repeat the previous two steps for the IPv4 Destination Address, except change the Destination
Address to 20.0.50.200.
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41. ToS Field
Select the button which appears in the ToS field.
42. DiffServ Value
Select the DiffServ radio button and using the drop down menu, select AF-31 as a code point.
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43. TCP Port Configuration
Expand the TCP Header and change the Destination TCP Port number to 80 and press OK.
44. Custom Header
Right-click on the TCP header and select Add Header.
45. Select Custom Header
Locate Custom and press OK.
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46. Configuring Custom Header
Expand the custom header and type in “47 45 54 1 2F 70 61 74 68 2F 74 6F 2F
66 69 6C 65 2F 69 6E 64 65 78 2E 68 74 6D 6C 1 48 54 54 50 2F 31
2E 30”.
Press OK once completed.
Hint: It is also possible to copy the above hex string and paste it into the Byte Pattern field by
using the Ctrl + v key stroke.
47. Setup FTP Traffic
Again, select Add Æ Add Raw Stream Block.
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48. FTP Stream Configuration
Name the Stream Block as FTP Traffic. Change the Frame Size to 1518. Change the rate to (3 Mbps
x 50) 150 Mbps. Change Setting, Priority to 3. Change the Settings Æ Burst size to 1. Select the
Frame tab.
49. Create New Frame
Select Frames Æ Create new Frame, then select Create new Frame.
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50. Adding TCP
Click on the Advanced Radio Button and under Category:Basic select “Tcp over IPv4”, press OK.
51. Source MAC Modifier
Select the Frame tab and then select the MAC Source. Click on Actions Æ Insert MAC Modifier.
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52. Modifier Increment
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
53. IPv4 Source Address
Select the IP Source Address, and change the value to 10.0.100.200. Next, select Insert IPv4
Modifier.
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54. IPv4 Modifier Increment
Increment the value by 50 and press OK. Repeat the same steps for the Destination Address,
except change the IP to 20.0.100.200 .
55. ToS Field
Select the IPv4 Æ ToS field and press the button which appears.
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56. DiffServ Code Point
Select the DiffServ radio button and use the drop down menu to choose AF-32 as a code point.
57. TCP Header
Expand the TCP Header and change the Destination TCP Port number to 21 and press OK.
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58. Setup Best Effort Traffic
Again, select Add Æ Add Raw Stream Block.
59. Best Effort Configuration
Name the Stream Block “Best Effort”. Change the Frame Size to 768. Change the rate to 300 Mbps.
Change Setting, Priority to 4. Change the Settings Æ Burst size to 1. Select the Frame tab.
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60. Add Header
Select Add Header.
61. Add UDP Header
Under the Category:IP locate the UDP header and press OK.
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62. Source MAC Modifier
Select the MAC Source and choose Actions Æ Add MAC Modifier.
63. Increment the Modifier
Increment the value by 50 and press OK. Perform the same action on the MAC Destination.
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64. IPv4 Source Modification
Click on the IP Source Address, and change the value to 10.0.200.200. Select the Add IP Modifier
option.
65. IPv4 Modifier Increment
Increment the value by 50 and press OK. Perform the same action on the Destination Address,
except change the IP Address to 20.0.200.200.
66. ToS Field
Select the IPv4 Æ ToS field, and then select the button which appears.
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67. DiffServ Code Point Selection
Select the DiffServ radio button and use the drop down menu to select Default as a code point.
68. UDP Header Configuration
Expand the UDP header and select the Destination Port. Next, select Actions Æ Insert Modifier.
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69. Random Modifier
Select Type Æ Random. Select OK twice.
70. Add Traffic to Remaining Bundle Ports
On the Ports Æ Bundle1 Æ Traffic Generator, select all rows, right-click and copy Stream Block.
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71. Paste Stream Blocks
Select Port Æ Bundle2 Æ Traffic Generator and right-click and select paste streams. Perform this
same action for Bundle3.
72. Technology Selector
In the toolbar, select the “Technology Selector” button.
73. LACP Test Selection
Under the Routing category, check “LACP” and press OK.
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74. LACP Setup
On the All Ports branch, select the LACP tab.
75. Activate LACP
On port Bundles 1-3, click Active.
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76. Start LACP
Select each of the just activated bundles, right-click and select LACP Æ Start.
77. Verify LACP is UP
Verify that for port Bundles 1-3, the LACP state is in “LACP UP” state.
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78. Setup Measured Port
On the Ports Æ Measured Port Æ Traffic Generator, paste the streams in the buffer.
79. Edit Stream Blocks
Edit each Stream Block and reverse the MAC and IP addresses.
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80. Enabling ARP/ND
Select Project Æ Settings Æ ARP/ND. Be sure to check Enable Cyclic ARP/ND and Enable ARP/ND
Before Transmission.
81. Setup the Analyzer
On the Ports Æ Measured Port Æ Traffic Analyzer. Enable the IPv4 Æ ToS field.
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82. Histogram Mode
On the Measured Port Æ Traffic Analyzer Æ Histogram tab, change the histogram mode to
“Sequence Run Length”.
83. Results Browser
In the right Results Browser, change the counter subscription to Stream Results Æ Filtered Stream
Results. Also, update the port to Measure Port.
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84. Run Test1 Æ QoS Stability over a Stable Bundle
In the tool bar, click the Start Traffic on all ports. Run the test for several hours. As variant of this
test, on the All Ports ÆAll Stream Block, click on a stream and use the slider in the tool bar to
reduce and expand the rate of an individual stream (Sum of stream <=100 Load) on the fly.
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85. Run Test2 Æ QoS Stability Over a Changing LACP Bundle
In the tool bar, click the Start Traffic on all ports. Run the test for several hours. While Traffic is
running, on the All Ports ÆLCAP Tab, select the Bundle2 Row. Right-click and select LACP Æ Stop
LACP. Examine the measured QoS parameters from the table before, during and after stopping the
Bundle2 LCAP participation. If QoS is being properly managed, the values of higher quality traffic
should be stable. Best effort traffic can change in any direction. Optionally, open the View Æ
Command Sequencer and create a command sequence to stop, wait and start LACP on different
combinations of ports. Multi-select event in the Command Sequencer and right-click. Group the
command together and loop multiple times. In the Results Browser, select the different QoS
Measured Values; then right-click and Add to Chart to see stability over time.
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Analysis
86. While Traffic is running, click on the Stream Results Æ Filtered Stream Results view. Click on the
Advanced Sequencing tab and look for out of sequence, lost, duplicated or late frames on any
code point.
Select the Histograms (Sequence Run Length) tab, and look for noticeable differences in the run
length.
Select the Basic tab, and look at min, average and maximum latencies, which should be very close
within the same code point and have a wider spread as the code point moves to best effort.
Compare measured results with the results in the above table to determine pass or fail of this test
case.
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Verify DiffServ QoS Stability over RSVP-TE Tunnels
Associated RFC
• RFC 2475
Spirent Communications Test Equipment Needed
• 2 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to verify the Device Under Test (DUT) can properly maintain minimum
levels of QoS by DiffServ Class interior to RSVP-TE tunnels. QoS levels tested and their passing behaviors
are:
Flow Code Point
Max Sequencing Errors
(%)
Max Latency Max Jitter Frame Size Load (Mbps)
MPEG-2 TS AF-43 1.0% 7 ms +/- 0.1 ms 1380 300
G.729 SIP
Voice
EF 0.1% 7 ms +/- 0.3 ms 78 50
HTTP AF-31 1.5% 10 ms +/- 0.7 ms 192 300
FTP AF-32 1.0% 10 ms +/- 0.7 ms 1500 300
Background 00 Any Any Any 576 50
Setup
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Step-by-Step
1. Configure the DUT
Login to the DUT and configure two ports names Tunnel and Clear. Configure each port for the
following configuration and turn on Route Redistribution:
Port IP Address Netmask Protocol
Tunnel 10.0.0.1 /16 OSPF (Area 0.0.0.0), RSVP-TE
Configure 1000 Sub-Interfaces with a starting VID of 2 and a starting IP Address of 10.0.1.1/24.
Configure the TE Parameters for 1 Mbps per tunnel:
Clear 20.0.0.1 /16 IP
Configure 1000 Sub-Interfaces with a starting VID of 2 and a starting IP Address of 20.0.1.1/24.
2. Reserve Ports on Spirent TestCenter
Launch Spirent TestCenter GUI and reserve the required ports.
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3. Rename Your Spirent TestCenter Ports
In your test tree, select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, click on the Port Name Cell and rename the port to Tunnel, and then Clear.
4. Technology Selector
In the toolbar, select the Technology Selector.
5. RSVP-TE Technology
Select the RSVP checkbox and press OK.
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6. Setting Up the Test
On the toolbar, select the Wizards button.
7. Selecting the Test
Under Configuration Wizards Æ Routing, run the RSVP-TE Æ Basic RSVP-TE wizard and press Next.
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8. Configure Topology
Click on the Topology Æ “Headend (PATH)/Tail-end (RESV)” option, and select Direction Æ
Bidirectional and press Next.
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9. Configure Left Side Ports
Enable Active next to the Tunnel port. Select the Sub-Interfaces Enable column for the Tunnel port,
and change the Sub-Interface Count to 100. Change the DUT IPv4 address to 10.0.1.1/24. Change
the DUT IPv4 Address Step to 0.1.1.0 and the VLAN ID to 2. Press Next to continue.
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10. Right Side Port Configuration
Enable the Active box, next to the Clear port. Check the Sub-Interface Enable box and change the
Sub-Interface Count to 100. Change the DUT IPv4 Address to 20.0.1.1 and the DUT IPv4 Address
Step to 0.1.1.0. Change the VLAN ID to 2 and press Next.
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11. Configure Routers
Under Protocols, select the RSVP-TE Options button.
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12. RSVP Options
Change the “Bandwidth per tunnel” to 12800 bytes/sec and select the Advanced button.
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13. RSVP Advanced Options
Check “Reliable delivery” and press OK.
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14. RSVP Options
No further changes are required, press OK to continue.
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15. Configure Routers
Again, no further changes are required. Press Next to continue.
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16. Number of Routes
Change the “Number of routes” to 2000 and press Next.
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17. Configure Tunnels
The defaults are okay, press Next to continue.
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18. Configure Traffic
Under “Load % from Ports”, change the rate to 10 and then press Finish.
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19. Add QoS Traffic
For each of the protocols described in the above QoS Table, add traffic across each created tunnel.
On the toolbar, click Wizards and select Traffic Æ Traffic Generator. Select both Tunnel and Clear
ports. Under Distribution, choose Pair. Change the Encapsulation to IPv4 and Orientation to
Bidirectional. Uncheck Stream only generation. Under Source and Distribution Æ Source, check
Tunnel Æ RSVP to select all RSVP Tunnels. On the Destination, choose Clear and the checkbox of
“Ospfv2” to select all routes.
Name the Stream Block according to the protocol. Change the load and rate according to the
above table. Enable the Vary Protocol and QoS and press the Configure button. Select the QoS tab
and then select the DiffServ radio button. Choose the appropriate DiffServ Level from the table
above and press OK. In the MPLS Binding section, select the Auto Select Tunnel button.
Uncheck the Expand Stream Block under ports, and press Finish. When the system asks if you
want to override the current config, say no. Repeat this step for each protocol.
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20. Setup the Analyzer
On the Ports Æ Tunnel Æ Traffic Analyzer and Ports Æ Clear Æ Traffic Analyzer, enable the IPv4
ÆToS field.
21. Histogram Selection
Choose Ports Æ Tunnel Æ Traffic Analyzer Æ Histograms tab. Use the Histogram Mode drop down
menu and select Sequence Run Length. Repeat this step on the Clear port, too.
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22. Results Browser
In right browser, change the subscription to Stream Results Æ Filtered Stream Results and change
the viewed port to the Tunnel port.
23. Run Test
On the toolbar, select the Start All Routers button. Wait for all tunnels to bind, then in the toolbar
click the Start All Traffic button.
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Analysis
24. While Traffic is running, select the Stream Results Æ Filtered Stream Results view. Select the
Advanced Sequencing tab, and look for out of sequence, lost, duplicated or late frames on any
code point.
Next, select the Histograms (Sequence Run Length), and look for noticeable differences in the run
length.
Select the Basic tab and look at min, average and maximum latencies, which should be very close
within the same code point and have a wider spread as the code point moves to best effort.
Compare measured results with the results in the above table to determine pass or fail of this test
case. Change the view to the East port and repeat analysis in this step.
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Router
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
BGP
OSPF
QoS Stability
Verify DiffServ QoS Stability Over Route Redistribution
Associated RFC
• RFC 2475
Spirent Communications Test Equipment Needed
• 2 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to verify QoS performance levels are maintained across route
redistribution. QoS levels tested and their passing behaviors are:
Flow Code Point
Max Sequencing Errors
(%)
Max Latency Max Jitter Frame Size Load (Mbps)
MPEG-2 TS AF-43 1.0% 7 ms +/- 0.1 ms 1380 300
G.729 SIP
Voice
EF 0.1% 7 ms +/- 0.3 ms 78 50
HTTP AF-31 1.5% 10 ms +/- 0.7 ms 192 300
FTP AF-32 1.0% 10 ms +/- 0.7 ms 1500 300
Background 00 Any Any Any 576 50
Setup
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Step-by-Step
1. Configure the DUT
Login to the Device Under Test (DUT) and configure two ports names East and West. Configure
each port for the following configuration and turn on Route Redistribution:
Port IP Address Netmask Protocol Notes
East 10.0.0.1 /16 BGP
DUT AS 10, RouterID 10.0.0.1, Emulation AS 11,
Emulated RouterID 10.0.0.2
West 20.0.0.1 /16 OSPFv2 Area 0.0.0.0
2. Reserve Ports on Spirent TestCenter
Launch Spirent TestCenter and reserve the required ports.
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3. Rename Your Spirent TestCenter Ports
In your test tree, select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port select the Port Name Cell and rename the port to East, then West.
4. Technology Selector
Select the Select Technologies button.
5. Adding BGP and OSPF
Locate BGP under the Routing protocol section and press OK.
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6. Add Routers
Right-click on All Ports Æ All Routers and select Add Multiple Routers.
7. Port Selection
Select all ports and press Next.
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8. Protocol Selection
Uncheck all Protocols and press Next.
9. Select Encapsulation
The defaults are okay, press Next to continue.
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10. Router Configuration
Verify that “Routers per port” is set to 1 and the “Use IPv4 address as router ID” is checked.
Change the IPv4 Æ IPv4 address to 10.0.0.2 and under step; select the “…” button.
11. IPv4 Step
Set the “Step per port” to 10.0.0.0 and press OK.
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12. Configure Routers
No further changes are required, press Next to continue.
13. Preview
Verify the configuration is correct and press Finish.
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14. Activating Routing Protocol
Select the Ports Æ East Æ Routers Æ BGP tab and enable the Active box to activate the peer.
15. AS Numbers
Change the AS number to 11 and the DUT AS Number to 10.
16. DUT IP
Scroll to the right and change the DUT IP Address to 10.0.0.1. Next, select the “Route Generator”
button.
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17. Route Generator
Select the Router and press Next.
18. Configure IPv4 Routes
Change the “Total number of routes to create” to 200,000, and change the “Prefix length
distribution type” to Internet and press Finish.
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19. West Port Configuration
Select the Ports Æ West Æ Routers Æ OSPFv2 tab and enable the Active check box.
20. LSA Generator
Select the LSA Generator button.
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21. Select Routers
Select the Router and press Next.
22. Configure Topology
Under Topology Type, select Grid. Change the “Numbers of rows” to 50; the “Number of columns”
to 50; and, the “Emulated router position” to Member of Grid. Press Next.
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23. Configure OSPF
The defaults are okay, press Next to continue.
24. Configure Stub Networks
Under Route Allocation Æ “Total number of routes to create” type in 10,000 and then press Finish.
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25. Summary
Verify the Summary is correct and press Close.
26. Starting Routers
On the toolbar, select the Start All Routers button.
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27. Results Browser
In the Results Browser, change the view to Routing Protocols OSPF Results (Right Viewer) and BGP
Results (Left Viewer). Wait until all routes were advertised. Check in your DUT config that all routes
are redistributed.
28. Setup QoS Traffic
For each of the QoS class of traffic in the above table, set up a bidirectional traffic stream using
the Stream Blocks attributes. In the toolbar, select the Wizards button and run the Traffic Æ Traffic
Wizard.
29. Port Selection
Select all ports and press Next.
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30. Endpoint Configuration
Choose Distribution Æ Pair, Orientation Æ Bidirectional and uncheck “Stream only generation”.
Under Source and Destination Æ Source select the BGP Router. On the Destination port, select the
OSPFv2 – Router 3. Press Add to create the endpoints. Finally, press Next to continue.
31. MPLS Binding
The defaults are okay, press Next to continue.
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32. Stream Block Configuration
Name the Stream Block appropriate to the protocol. Set the Frame Size and Load according to the
above table. Check “Vary Protocol and QoS” and select the Configure button. In the QoS
Configuration window, select the QoS Tab. Select the DiffServ radio button and set the appropriate
DiffServ code point. Set the Scheduling mode to Rate Based. Uncheck “Expand stream blocks
under ports” and press Finish.
Repeat this step until all DiffServ code points and traffic are created.
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33. ARP/ND Enable
Under Project Æ Settings Æ ARP/ND make sure “Enable ARP/ND Before Transmission” is checked.
34. Setup the Analyzer
On the Ports Æ East Æ Traffic Analyzer and Ports Æ West Æ Traffic Analyzer enable the IPv4 Æ
ToS field.
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35. Histogram Selection
Choose Ports Æ East Æ Traffic Analyzer Æ Histograms tab. Use the Histogram Mode drop down
menu and select Sequence Run Length. Repeat this step on the West port, too.
36. Results Browser
In right browser, change the subscription to Stream Results Æ Filtered Stream Results and change
the viewed port to the West port.
37. Run Traffic
In the Toolbar, select. Start All Traffic.
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Analysis
38. While Traffic is running, select the Stream Results Æ Filtered Stream Results view. Select the
Advanced Sequencing tab and look for out of sequence, lost, duplicated or late frames on any
code point.
Select the Histograms (Sequence Run Length) tab and look for noticeable differences in the run
length.
Click on Basic and look at min, average, and maximum latencies, which should be very close
within the same code point and have a wider spread as the code point moves to best effort.
Compare measured results with the results in the above table to determine pass or fail of this test
case. Change the view to the East port and repeat analysis in this step.
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Router
Best Effort
QoS High
QoS Medium
Best Effort
QoS High
QoS Medium
Verify the Weighted Fair Queuing (WFQ) QoS Algorithm
Associated RFC
• RFC 2475
Spirent Communications Test Equipment Needed
• 2 Ethernet Ports, 10/100/1000
• Spirent TestCenter™ Chassis
• Miscellaneous Cables
Objective
The objective of this test case is to verify the Weighted Fair Queuing (WFQ) algorithm is properly
implemented and is functional. In this test, we will use three queues with the following attributes based on
DiffServ Code Points:
Flow Code Point Injection Rate Weight Bandwidth Ratio Measured Rate Frame Size
MPEG-2
TS
AF-43 300 Mbps 100 100 / (100+75+25) = .5 150 Mbps 1380
G.729 SIP
Voice
EF 100 Mbps 75 75 / (100+75+25) = .375 37.5 Mbps 78
FTP AF-32 600 Mbps 25 25 / (100+75+25) = .125 75 Mbps 1500
Setup
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Step-by-Step
1. Configure the DUT
Login to the Device Under Test (DUT) and configure two ports called East and West. Configure the
East port to be 10.0.0.1/16 and the West port to be 20.0.0.1/16. Configure WFQ with the above
weights. Enable IP Forwarding.
2. Reserve Ports on Spirent TestCenter
Launch Spirent TestCenter and reserve the required ports.
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3. Rename Your Spirent TestCenter Ports
In your test tree, select All Ports. For each port, uncheck Append Location to Port Name. Starting at
the top port, select the Port Name Cell and rename the port to East, then West.
4. Setup AF-43 Traffic on the East Port
Under Ports Æ East ÆTraffic Generator, change the scheduling mode to Rate Based. Then select
Add Æ Add Raw Stream Block.
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5. General Stream Block Configuration
Change the Frame Size to 1380 and the rate to 300 Mbps. Update the name to AF-43 and select
the Frame tab.
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6. Frame Configuration
Expand the IPv4 Header. For the Source IP Address, type 10.0.0.2 and the destination 20.0.0.2.
Select the “…” button which appears in the IPv4 Æ ToS field.
7. DiffServ Code Point Value
Select the DiffServ radio button and then use the DSCP Diffserv Codepoint Æ Codepoint Name
drop down menu and choose AF4 3. Press OK two times.
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8. Filling Out Traffic
Right-click on the stream you just created and select duplicate.
9. Duplication
Duplicate the stream two times and press OK.
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10. Stream Editing
Edit each stream and change the Frame size and load according to the table above. Also, under
the frame tab, increment the MAC addresses and the IP addresses. Make sure to update the ToS
field.
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11. Copying Streams
Select all the streams and right-click and select Copy Stream Block.
12. Filling Out Destination
Under West Æ Traffic Generator, paste the copied streams. Then edit the streams and reverse the
MAC source with the MAC Destination. Also, reverse the Source IP with the Destination IP.
13. Setup the Analyzer
On the Ports Æ West Æ Traffic Analyzer and Ports Æ East Æ Traffic Analyzer, enable the IPv4 Æ
ToS field.
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14. Results Browser
In right browser, change the subscription to Stream Results Æ Filtered Stream Results and change
the viewed port to the West port.
15. Run Traffic
On the toolbar, select the “Run all traffic” button.
Analysis
16. Under Stream Results Æ Filtered Stream Results, by DiffServ Level, look for the RX Bit rate.
Compare each DiffServ Code Point received bandwidth with the Measured Rate in the table above.
If WFQ is working, they should be the same.
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Glossary
AS.
(Autonomous System) A part of a network under a single administrative domain, usually running a
single internal router protocol.
BGP.
(Border Gateway Protocol) The exterior gateway protocol used for distributing routes over the
Internet. Currently, Version 5 (BGP-4) is used.
CIR.
(Committed Information Rate) The average bandwidth that an ISP guarantees to a customer at any
given time. The bandwidth should not drop below this given rate in typical network conditions.
CoS.
(Class of Service) This is a 3-bit field in an Ethernet frame that is used when 802.1Q is utilized.
The field provides a value between 0 and 7 used by Quality of Service (QoS) to determine the
priority of the traffic.
DiffServ.
(Differentiated Services) Used for providing Quality of Service (QoS) guarantees in an IP network.
DSCP.
(Differentiated Services Code Point) DSCP is a field in the IP header used to classify the priority of
the frame.
LACP.
(Link Aggregation Control Protocol) LACP is part of the IEEE 802.3ad specification. LACP controls
the ability to use several physical ports together to form a single logical channel.
Q-in-Q.
Expands the VLAN space by providing the ability to tag previously tagged packets, producing a
double-tagged frame.
QoS.
(Quality of Service) QoS is the ability of a network to meet a certain traffic contract.
RSVP.
(Resource Reservation Protocol) A signaling protocol that reserves resources throughout an IP
network. Supports IP Quality of Service (QoS).
SLA.
(Service Level Agreement) An agreement (usually a contract) between a service provider and a
customer. Guarantees a certain quantitative and/or qualitative level of service.
TOS.
(Type of Service) A 1-byte field in the IP Header that defines how the datagram should be handled
by the networks during transportation.
VLAN.
(Virutal LAN) A network whose elements behave as if they are connected to the same physical LAN
even though they might be located on separate physical networks.
VPLS.
(Virtual Private LAN Services) VPLS is used with Layer 2 Virtual Private Networks (VPNs) to support
many sites in a single network.
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VPN.
(Virtual Private Network) A private network created by utilizing shared resources within a public
network.
WFQ.
(Weighted Fair Queuing) WFQ is a way to schedule different data packets and allowing a
scheduling priority that is able to handle statistically multiplexed data flows.
WRED.
(Weighted Random Early Detection) WRED provides a management system for queues and also
has the ability to provide congestion avoidance.
Spirent Communications is a worldwide provider of integrated
performance analysis and service assurance systems for
next-generation network technologies.
Our solutions accelerate the profitable development and
deployment of network equipment and services by emulating
real-world conditions in the lab and assuring end-to-end
performance of large-scale networks.
Spirent performance analysis solutions include instruments and
systems that measure and analyze the performance of network
equipment, particularly the devices that route voice and data
messages to their destination. Our service assurance solutions
include remote test, fault and performance management systems
that let network service providers quickly identify network
faults and monitor real-time performance. Spirent’s integrated
performance analysis and service assurance solutions enable
our customers to more rapidly develop and certify new devices,
lowering the cost of widespread deployment and operation of
new networking services.
© 2006 Spirent Communications, Inc. All of the company names and/or brand names and/or product
names referred to in this document, in particular the name “Spirent” and its logo device, are either
registered trademarks or trademarks pending registration in accordance with relevant national laws.
All rights reserved. Specifications subject to change without notice.
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