Spirent Journal of Access and Edge PASS Test Methodologies
Access and edge networks, frequently called the last mile, are becoming a critical component of the end-user experience. Last-mile technology carries signals from the telecommunication backbone along the relatively short distance (hence, the last mile) to and from the home or business. Or to put it another way, it is the infrastructure at the neighborhood level. This journal presents a comprehensive set of test cases to measure PASS of the Device Under Test (DUT).
PASS
Spirent Journal of Access
and Edge PASS Test
Methodologies
February 2011 Edition
Spirent Journal of Access and Edge PASS Test Methodologies | © Spirent Communications 2011
1
Introduction
Today’s Devices Under Test (DUT) represent complex, multi-protocol network elements with an emphasis
on Quality of Service (QoS) and Quality of Experience (QoE) that scale to terabits of bandwidth across the
switch fabric. The Spirent Catalogue of Test Methodologies represents an element of the Spirent test
ecosystem that helps answer the most critical Performance, Availability, Security and Scale Tests (PASS)
test cases. The Spirent Test ecosystem and Spirent Catalogue of Test Methodologies are intended to help
development engineers and product verification engineers to rapidly develop and test complex test
scenarios.
How to use this Journal
This provides test engineers with a battery of test cases for the Spirent Test Ecosystem. The journal is
divided into sections by technology. Each test case has a unique Test Case ID (Ex. TC_MBH_001) that is
universally unique across the ecosystem.
Tester Requirements
To determine the true capabilities and limitations of a DUT, the tests in this journal require a test tool that
can measure router performance under realistic Internet conditions. It must be able to simultaneously
generate wire-speed traffic, emulate the requisite protocols, and make real-time comparative
performance measurements. High port density for cost-effective performance and stress testing is
important to fully load switching fabrics and determine device and network scalability limits.
In addition to these features, some tests require more advanced capabilities, such as
Integrated traffic, routing, and MPLS protocols (e.g., BGP, OSPF, IS-IS, RSVP-TE, LDP/CR-LDP) to
advertise route topologies for large simulated networks with LSP tunnels while simultaneously
sending traffic over those tunnels. Further, the tester should emulate the interrelationships
between protocol s through a topology.
Emulation of service protocols (e.g., IGMPv3, PIM-SM, MP-iBGP) with diminution.
Correct single-pass testing with measurement of 41+ metrics per pass of a packet.
Tunneling protocol emulation (L2TP) and protocol stacking.
True stateful layer 2-7 traffic.
Ability to over-subscribe traffic dynamically and observe the effects.
Finally, the tester should provide conformance test suites for ensuring protocol conformance and
interoperability, and automated applications for rapidly executing the test cases in this journal.
Further Resources
Additional resources are available on our website at http://www.spirent.com
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Table of Contents
Testing Access and Edge .........................................................................................................3
ACS_001 Determine whether the DUT (LNS) can successfully connect PPPoEv6oL2TP
sessions and run data plane traffic ...................................................................... 4
ACS_002 Determine whether the DUT (LAC) can successfully connect PPPoEv6 and L2TP
sessions and run data plane traffic ...................................................................... 7
ACS_003 Determine whether the DUT (LNS) can successfully connect the PPPoEv6oL2TP
sessions, carry the DHCP-PD messages over the appropriate L2TP Tunnels and
successfully run data plane traffic over them .................................................... 10
ACS_004 Determine whether the DUT (LAC) can successfully connect the PPPoEv6/L2TP
sessions, bind the DHCP-PD sessions and run them over the correct L2TP tunnels
and successfully run data plane traffic .............................................................. 13
ACS_005 Can the DUT process DHCPv6 ............................................................................ 16
ACS_006 Determine how fast the DUT processes multicast Join/Leave messages .......... 20
ACS_007 Can the DUT successfully process 802.1x authentication and then bind DHCP
sessions .............................................................................................................. 25
ACS_008 Can the DUT sustain the PPPoX session setup rate without spiking the CPU .... 28
ACS_009 ALP over access with realism ............................................................................. 31
Appendix A – Telecommunications Definitions ..................................................................... 35
Appendix B – Layer 2 802.1q CoS .......................................................................................... 42
Appendix C – RFC 2474 Layer 3 QoS ...................................................................................... 43
Appendix D – RFC 2474 Layer 3 QoS Definitions .................................................................... 44
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Testing Access and Edge
Access and edge networks, frequently called the last mile, are becoming a critical component of the end-
user experience. Last-mile technology carries signals from the telecommunication backbone along the
relatively short distance (hence, the last mile) to and from the home or business. Or to put it another way,
it is the infrastructure at the neighborhood level.
In many communities, last-mile technology
represents the major remaining challenge
because the cost of providing high-speed,
high-bandwidth services to individual
subscribers in remote areas can be higher than
the service provider would like. Laying wire
and fiber is an expensive, high-maintenance,
environmentally-demanding undertaking.
Experts hope that broadband wireless
networks will eventually provide the solution
and meet everyone's needs.
PPP (Point-to-Point Protocol) is a protocol for
communication between two computers using a serial interface, typically a personal computer connected
by phone line to a server. For example, your Internet server provider may provide you with a PPP
connection so that the provider's server can respond to your requests, pass them on to the Internet, and
forward responses back to you. PPP uses the Internet protocol (IP) and other protocols and resides at
layer 2, the data link layer, of the Open Systems Interconnection (OSI) reference model. Essentially, it
packages your computer's TCP/IP packets and forwards them to the server where they can actually be put
on the Internet.
PPP is a full-duplex protocol that can be used on various physical media, including twisted pair, fiber optic
lines or satellite transmission. It uses a variation of High Speed Data Link Control (HDLC) for packet
encapsulation.
Provider Backbone Bridges (PBB) (aka MAC-in-MAC) IEEE 802.1ah. Ethernet Provider Backbone Bridge
(PBB) standards were approved in 2005. PBB is available in carrier layer 2 Ethernet switches today and it
allows for layering the Ethernet network into customer and provider domains with complete isolation
among their MAC addresses. It defines a B-DA and B-SA to indicate the backbone source and destination
address. It also define B-VID (backbone VLAN ID) and I-SID (Service Instance VLAN ID).
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ACS_001 Determine whether the DUT (LNS) can successfully
connect PPPoEv6oL2TP sessions and run data plane
traffic
Abstract
This test determines whether the DUT (LNS) can successfully connect PPPoEv6oL2TP sessions
and run data plane traffic. In this test case, Spirent TestCenter ports emulate the LAC and the
PPPoEv6oL2TP client sessions establish with the DUT (LNS) which also attach to other Spirent
TestCenter ports that emulate the ISP (Static IPv6 devices) to enable bi-directional data traffic.
The PPPoEv6oL2TP client sessions should successfully connect and the user should successfully
run bi-directional data traffic.
Description
With the adoption of IPv6, many ISPs are deploying IPv6-capable devices. In this test case, test
ports emulate the LAC and PPPoEv6 clients and are connected to the DUT which are the LNS. The
DUT is also connected to other test ports which emulate the regular IPv6 clients to run bi-
directional traffic between the PPPoEv6 sessions and the IPv6 clients.
Relevance
To verify the IPv6 readiness of the devices
To verify that PPPoEv6 sessions can be established with the DUT when it is the LNS
To verify that the PPPoEv6oL2TP (LAC) tunnels can be established with the DUT when it is the
LNS
To verify that bi-directional traffic can be passed between the PPPoEv6 and IPv6 clients
through the DUT and also to verify that the traffic is routed to the appropriate sessions
Version
1.0
Test Category
Testing Access/Edge
PASS
[x] Performance [x] Availability [ ] Security [x] Scale
Required Tester Capabilities
Native IPv6, PPPoX and L2TPv4 (LAC and LNS) Emulation Support
PPPoEv6 Emulation Support
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Topology
Test Procedure
1. Create L2TPv4 (LAC) devices along with the PPPoEv6 clients on 1st port.
a. Input the appropriate PPP and L2TP parameters/authentication to match the DUT.
2. Create a regular IPv6 client on the 2nd port.
3. Establish the L2TP tunnel.
4. Establish the PPPoEv6 sessions.
5. Run bi-directional traffic.
6. Scale up the configuration to reach the DUT limits.
Variables & Relevance
Variable Relevance
Number of PPPoEv6 sessions Start with 1 and scale up according to the DUT limits.
Number of sessions per L2TP
tunnel
Start with 1 and scale up to determine whether a single
L2TP tunnel can successfully establish multiple PPPoEv6
sessions.
Number of static IPv6 Clients/hosts Increase to determine whether the DUT can handle the
increased traffic/load while maintaining the PPPoEv6
sessions and the L2TP tunnels.
Authentication Parameters Change the Authentication parameters to determine
whether the DUT can handle various combinations.
Desired Result
The DUT should be able to successfully establish both the PPPoEv6 sessions and the L2TP tunnels
and pass bi-directional traffic.
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Key Measured Metrics
Statistic Relevance
Number of PPPoEv6 sessions Up Verifies that the DUT is able to establish the sessions.
Number of L2TP tunnels Up Verifies that the DUT is able to establish the tunnels.
Stray frames Verifies that the DUT is forwarding the frames correctly to
appropriate PPPoEv6 session.
Analysis
The DUT should be to successfully establish both the PPPoEv6 sessions and the L2TP tunnels as
well as be able to pass bi-directional traffic between the PPPoEv6 sessions and the static IPv6
clients/hosts.
The DUT should be able to maintain PPPoEv6 sessions and L2TP tunnels over a period of time
with and without traffic.
Check the error code (as defined in the PPP and L2TP protocol stack) if the DUT is not able to
establish the PPPoEv6 session or the L2TP tunnel or if the DUT drops the connection after
successfully establishing it.
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ACS_002 Determine whether the DUT (LAC) can successfully
connect PPPoEv6 and L2TP sessions and run data plane
traffic
Abstract
This test determines whether the DUT (LAC) can successfully connect PPPoEv6 and L2TP
sessions/tunnels and run data plane traffic. In this test case, test ports establish PPPoEv6 client
sessions with the DUT (LAC), which is attached to other terst ports emulating the LNS along with
the PPPoEv6 server. These ports establish L2TP tunnels with the DUT (LAC). Both the PPPoEv6
clients and the L2TP tunnels should be successfully established and the user should be able to
run bi-directional traffic between the PPPoEv6 clients and the PPPoEv6 server.
Description
With the adoption of IPv6, many ISPs are deploying IPv6-capable devices. In this test case, test
ports emulate PPPoEv6 clients connected to the DUT (LAC) which are connected to other test
ports emulating the LNS with the PPPoEv6 Server. After successfully establishing the PPPoEv6
sessions, bi-directional traffic is generated between the PPPoEv6 clients and the server to
determine whether the DUT can pass it successfully.
Relevance
To verify the IPv6 readiness of the devices
To verify that PPPoEv6 sessions can be established when the DUT is a LAC
To verify that the DUT can pass bi-directional traffic between the PPPoEv6 clients and the
LNS/PPPoEv6 server.
Version
1.0
Test Category
Testing Access/Edge
PASS
[x] Performance [x] Availability [ ] Security [x] Scale
Required Tester Capabilities
Native IPv6, PPPoX and L2TPv4 (LAC and LNS) Emulation Support
PPPoEv6 Client and Server Emulation Support
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Topology
Test Procedure
1. Configure PPPoEv6 client emulation on one port.
2. Configure the DUT as LAC.
3. Configure the 2nd port as PPPoEv6 server emulation along with LNS.
4. Input the appropriate PPPoEv6 and L2TP parameters/authentication.
5. Start the PPPoEv6 server along with the LNS emulation.
6. Establish the PPPoEv6 sessions.
7. Run bi-directional traffic.
8. Scale up the configuration to reach the DUT limits.
Variables & Relevance
Variable Relevance
Number of PPPoEv6 sessions Start with 1 and scale up according to the DUT limits.
Number of PPPoEv6 servers Start with 1 and distribute the number of clients into more
than 1 server to determine the DUT limits.
Desired Result
The DUT should be able to successfully establish the PPPoEv6 sessions and pass bi-directional
traffic.
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Key Measured Metrics
Statistic Relevance
Number of PPPoEv6 sessions Up Verifies that the DUT is able to establish the sessions.
Number of L2TP tunnels Up Verifies that the DUT is able to establish the tunnels.
Stray frames Verifies that the DUT is forwarding the frames correctly to
appropriate PPPoEv6 entity.
Analysis
The DUT should be to successfully establish both the PPPoEv6 sessions and the L2TP tunnels as
well as be able to pass bi-directional traffic through between the PPPoEv6 clients and the server.
The DUT should be also able to maintain the PPPoEv6 sessions and the L2TP tunnels over a
period of time with and without traffic.
Check the error code (as defined in the PPP and L2TP protocol stack) if the DUT is not able to
establish the PPPoEv6 session/L2TP tunnel or if the DUT drops the connection after successfully
establishing it.
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ACS_003 Determine whether the DUT (LNS) can successfully
connect the PPPoEv6oL2TP sessions, carry the DHCP-PD
messages over the appropriate L2TP Tunnels and successfully run
data plane traffic over them
Abstract
This test determines whether the DUT (LNS) can successfully connect the PPPoEv6oL2TP
sessions, delegate the DHCP-PD prefixes and run data plane traffic. In this test case, test ports
emulate the LAC and the DHCP-PDoPPPoEv6oL2TP client sessions establish with the DUT (LNS)
which is attached to other test ports emulating a DHCP-PD Server plus the ISP (Static IPv6
devices) to send the data plane traffic. Both the PPPoEv6 and L2TP sessions should connect
successfully before DHCP-PD prefix delegation and DHCP-PD messages should be sent and
received over the correct L2TP tunnel and sessions IDs. In addition, the DUT should also
successfully pass bi-directional data plane traffic.
Description
With the adoption of IPv6, many ISPs are deploying IPv6-capable devices. DHCP-PD and PPPoEv6
are evolving as the primary choice due to the scalability and flexibility offered by these protocols.
In this test case, test ports emulate the LAC and have DHCP-PD, PPPoEv6 and L2TP tunnels
configured on the same hosts. A 2nd port emulates a DHCP-PD server as well as static IPv6 hosts.
DHCP-PDoPPPoEv6oL2TPv4 sessions are established and bi-directional traffic run through the
DUT.
Relevance
To verify the IPv6 readiness of the devices.
To verify that DHCP-PDoPPPoEv6oL2TP sessions can be established when the DUT is the LNS.
To verify that the DUT can pass bi-directional traffic and that DHCP-PD messages are routed
properly over the correct the Tunnels and the sessions IDs.
Version
1.0
Test Category
Testing Access/Edge
PASS
[x] Performance [x] Availability [ ] Security [x] Scale
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Required Tester Capabilities
Native IPv6, PPPoX and L2TPv4 (LAC and LNS) Emulation Support
PPPoEv6 Emulation Support
DHCP-PD Client and Server Emulation Support
Topology
Test Procedure
1. Configure DHCP-PD, PPPoEv6 and L2TP client emulation on the same hosts/client.
a. Input the matching the Authentication parameters.
2. Configured DHCP-PD server and static IPv6 hosts on another port.
3. Start the DHCP-PD server.
4. Establish the L2TP connection.
5. Establish the PPPoEv6 sessions.
6. Establish the DHCP-PD client bindings.
7. Run bi-directional traffic.
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Variables & Relevance
Variable Relevance
Number of PPPoEv6 sessions User can start with 1 and then scale up according to the
DUT limits
Number of sessions per L2TP
tunnel
User can start with 1 and then scale up to see if a single
L2TP tunnel can successfully establish multiple PPPoEv6
sessions
Number of static IPv6 Clients/hosts User can increase this number to see if the DUT can handle
the increased traffic/load while maintaining the PPPoEv6
sessions and the L2TP tunnels
Number of DHCP-PD Clients Increase this number to see whether the DUT handle the
additions along with the PPPoEv6 and L2TP connections
Authentication Parameters Change the Authentication parameters to see if the DUT
can handle various combinations
Desired Result
The DUT should be able to successfully establish both the PPPoEv6 sessions and the L2TP tunnels
along with the DHCP-PD bindings and pass bi-directional traffic through. Also, DHCP-PD prefix
delegation should happen only after PPPoEv6 and L2TP tunnels are established. DHCP-PD
messages should be carried over correct Tunnel and Session IDs.
Key Measured Metrics
Statistic Relevance
Number of PPPoEv6 sessions Up Verifies that the DUT is able to establish the sessions.
Number of L2TP tunnels Up Verifies that the DUT is able to establish the tunnels.
Number of DHCP-PD Client Up Verifies that the DUT is able to establish the DHCP-PD
bindings.
Stray frames Verifies that the DUT is forwarding the frames correctly to
appropriate PPPoEv6 session.
DHCP-PD Prefix delegation The DHCP-PD prefix delegation should happen only after
the PPPoEv6 sessions and L2TP tunnels are established.
The DHCP-PD messages should be sent over the correct
Tunnels and Session IDs.
Analysis
The DUT should be able to successfully establish both PPPoEv6 sessions and L2TP tunnels along
with DHCP-PD bindings and pass bi-directional traffic through. Also, DHCP-PD prefix delegation
should only happen after PPPoEv6 and L2TP tunnels are established. DHCP-PD messages should
be carried over correct Tunnel and Session IDs.
If DHCP-PD messages are not routed over the appropriate Session ID/Tunnel or if DHCP-PD prefix
delegation is done before PPPoEv6/L2TP tunnels get established, it indicates an issue with the
DUT implementation.
Check the error code (as defined in the PPP, L2TP and DHCP-PD protocol stack) if the DUT is not
able to establish the PPPoEv6 session/L2TP tunnel/DHCP-PD binding or if the DUT drops the
connection after successfully establishing it.
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ACS_004 Determine whether the DUT (LAC) can successfully
connect the PPPoEv6/L2TP sessions, bind the DHCP-PD
sessions and run them over the correct L2TP tunnels and
successfully run data plane traffic
Abstract
This test determines whether the DUT (LAC) can successfully connect the PPPoEv6 and the L2TP
sessions/tunnels, bind the DHCP-PD sessions and run data plane traffic. In this test case, test
ports establish DHCP-PDoPPPoEv6 client sessions with the DUT (LAC) which also is attached to
other test ports emulating the LNS and the DHCP-PD and PPPoEv6 server. Both PPPoEv6 and the
DHCP-PD on the client side should be able to successfully establish the sessions and the L2TP
tunnels should also be successfully established from the LNS side. Also, DHCP-PD messages
should be sent and received over the correct L2TP tunnels and sessions IDs. In addition, the DUT
should be able to successfully pass bi-directional data plane traffic.
Description
With the adoption of IPv6, many ISPs are deploying IPv6-capable devices. DHCP-PD and PPPoEv6
are evolving as the primary choice due to the scalability and flexibility offered by these protocols.
In this test case, test ports emulate DHCP-PD and PPPoEv6 clients and the DUT is the LAC.
Another test port emulates the LNS and the DHCP-PD and PPPoEv6 server. After successfully
establishing the PPPoEv6 and DHCP-PD sessions, bi-directional traffic is generated.
Relevance
To verify the IPv6 readiness of the devices.
To verify that PPPoEv6oL2TP sessions can be established through the DUT.
To verify that the DHCP-PD sessions can be established through the DUT.
To verify that the DHCP-PD messages are sent over the correct Tunnels and Sessions IDs.
To verify that the DUT can pass bi-directional traffic in this scenario.
Version
1.0
Test Category
Testing Access/Edge
PASS
[x] Performance [x] Availability [ ] Security [x] Scale
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Required Tester Capabilities
Native IPv6, PPPoX and L2TPv4 (LAC and LNS) Emulation Support
PPPoEv6 Client and Server Emulation Support
DHCP-PD Client and Server Emulation Support
Topology
Test Procedure
1. Configure DHCP-PD, PPPoEv6 client emulation on the same hosts/client.
a. Input the matching the Authentication parameters.
2. Configured LNS, DHCP-PD and PPPoEv6 server on another port.
3. Start the DHCP-PD and PPPoEv6 servers.
4. Establish the L2TP connection.
5. Establish the PPPoEv6 sessions.
6. Establish the DHCP-PD client bindings.
7. Run bi-directional traffic.
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Variables & Relevance
Variable Relevance
Number of PPPoEv6 sessions Start with 1 and scale up according to the DUT limits.
Number of sessions per L2TP
tunnel
Start with 1 and then scale up to determine whether a
single L2TP tunnel can successfully establish multiple
PPPoEv6 sessions.
Number of DHCP-PD Clients/hosts Increase this number to determine whether the DUT can
support the additions along with the PPPoEv6 and L2TP
connections.
Authentication Parameters Change the Authentication parameters to determine
whether the DUT can support various combinations.
Desired Result
The DUT should be able to successfully establish both the PPPoEv6 sessions and the L2TP tunnels
along with the DHCP-PD bindings and pass bi-directional traffic through. Also, the DHCP-PD prefix
delegation should happen only after the PPPoEv6 and L2TP tunnels are established. The DHCP-PD
messages should be carried over the correct Tunnel and Session IDs.
Key Measured Metrics
Statistic Relevance
Number of PPPoEv6 sessions Up Verifies that the DUT is able to establish the sessions.
Number of L2TP tunnels Up Verifies that the DUT is able to establish the tunnels.
Number of DHCP-PD Clients Up Verifies that the DUT is able to establish the DHCP-PD
bindings.
Stray frames Verifies that the DUT is forwarding the frames correctly to
appropriate PPPoEv6 session.
DHCP-PD Prefix delegation The DHCP-PD prefix delegation should happen only after
the PPPoEv6 sessions and L2TP tunnels are established.
The DHCP-PD messages should be sent over the correct
Tunnels and Session IDs.
Analysis
The DUT should be able to successfully establish both the PPPoEv6 sessions and the L2TP tunnels
along with the DHCP-PD bindings and pass bi-directional traffic through. Also, the DHCP-PD prefix
delegation should happen only after the PPPoEv6 and L2TP tunnels are established. The DHCP-PD
messages should be carried over correct Tunnel and Session IDs.
If the DHCP-PD messages are not routed over the appropriate Session ID/Tunnel or if the DHCP-
PD prefix delegation is done before the PPPoEv6/L2TP tunnels get established, it indicates an
issue with the DUT implementation.
Check the error code (as defined in the PPP, L2TP and DHCP-PD protocol stack) if the DUT is not
able to establish the PPPoEv6 session/L2TP tunnel/DHCP-PD binding or if the DUT drops the
connection after successfully establishing it.
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ACS_005 Can the DUT process DHCPv6
Abstract
This test case determines whether the DUT can handle DHCPv6 bindings and other stack
messages properly. This is achieved by emulating DHCPv6 clients and verifying the ability of the
DUT. This test verifies the availability of the DHCPv6 stack.
Description
More service providers have adopted IPv6 Technology and hence DHCPv6 implementation
becomes critical for network equipment manufacturers.
In this test case, test ports emulate DHCPv6 clients and establish sessions with the DUT which is
configured as the DHCPv6 server.
Target Users
Engineering, Product Verification
Target Device Under Test (DUT)
Any DHCPv6-capable DUT
Reference
RFC 3315
Relevance
This test case will test the ability of the DUT to establish DHCPv6 sessions and stress the DUT
stack by scaling up the configuration.
Version
1.0
Test Category
Testing Access/Edge
PASS
[x] Performance [ ] Availability [ ] Security [x] Scale
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Required Tester Capabilities
The tester needs to support:
Full DHCPv6 emulation support
Real-time results showing the DHCPv6 state machine changes as well as control plane
counters.
Ability to repeat the test consistently.
Topology Diagram
Test Procedure
1. Create a DHCPv6 client device, keeping the default options for rapid commit mode,
DUID and timer options.
2. Match the same the settings on the DUT.
3. Start DHVPv6 binding.
4. Observe the DHCPv6 counters in real time and verify that the sessions achieve the
Bound state
5. Also, look for other counters like currently bound sessions, bind rate, total failed, total
failed etc.
6. To test the DUT state machine, initiate other DHCPv6 commands, such as Confirm
DHCPv6 address, Rebind DHCPv6, and Renew DHCPv6 to see whether the DUT responds
with the appropriate messages
7. Keep the session bound for an extended period of time, at least until the lease time
expires, and check whether the DHCPv6 renews and rebinds according to the configured
timers as well as conforms to the state machine.
8. To scale to the DUT limits, increase the number of DHCPv6 sessions and repeat Steps 2
to 7.
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9. End test.
Control Variables & Relevance
Variable Relevance Default Value
Number of DHCPv6
Clients Configured
Scale testing for the DUT 1
Key Measured Metrics
Matric Relevance Metric Unit
Currently Bound
Sessions
Number of sessions currently in a Bind state with
an active IPv6 address for the host.
Equal to the
number of DHCPv6
Client configured
Bind Rate Indicates how fast the DUT can process the
DHCPv6 messages and get them to a Bind state.
Sessions/Sec
Number of Solicit
messages Transmitted
Indicates how many DHCPv6 solicit messages
were sent to the DUT.
Count per device
Number of Advertise
messages Received
Indicates how many DHCPv6 Advertise messages
were received from the DUT.
Count per device
Number of Request
messages Transmitted
Indicates how many DHCPv6 Request messages
were sent to the DUT.
Count per device
Number of Reply
message received
Indicates how many DHCPv6 Reply messages
were received from the DUT.
Count per device
Min, Avg and Max
Solicit to Advertise
time
Indicates the difference between the time the
client sends the solicit message and receives the
Advertise message from the DUT. This shows
how fast the DUT is able to process the Solicit
messages
msec
Min, Avg., Max Solicit
to Reply time
Indicates the difference between the time the
client sends the solicit message and received the
Reply message from the DUT. This shows the
total time it took to bind the DHCPv6 device.
msec
Desired Result
The DUT should be able to successfully bind the DHCPv6 sessions and conform to all the standard
DHCPv6 messages used in the binding process
Analysis
The DUT should be able to successfully bind the DHCPv6 sessions and conform to all the standard
DHCPv6 messages used in the binding process.
The DHCPv6 state machine is similar to the DHCPv4 state machine in the following sense:
The client sends the solicit message.
The DUT replies with a Advertise message in response to the solicitation message.
The client sends a Request message in response to the Advertise message.
The DUT sends a Reply message to confirm the binding.
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The DUT should also be able to maintain the current DHCPv6 bindings when more clients are
added and also be able to maintain these bindings at least until the lease times allocated.
If the DHCPv6 session is not binding, check the appropriate control plane counters as described
above to determine the root cause. Check the Solicit to Advertise and Solicit to Reply times to
determine whether the DUT processes these bindings within the expected time frames.
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ACS_006 Determine how fast the DUT processes multicast
Join/Leave messages
Abstract
This test determines how fast the DUT can process multicast Join/Leave messages using the IPTV
Channel Zapping Tests. In this test case, test ports emulate a multicast source sending traffic to
multiple groups (channels) connected to the DUT which are also connected to other test ports
which emulate client behavior by joining and leaving multiple channels. The DUT should not
forward multicast traffic until at least one Join is received for that particular group and should
stop sending traffic once the last Leave is received for that particular group. The DUT should
forward the traffic to appropriate groups. The DUT should be able to leave a group and join the
next group within the minimum time possible.
Description
With the advent of digital content, more broadcasters and network channels have started
streaming digital video – packetized instead of analog signals – thereby putting an enormous
burden on the service providers (and NEMs) to have devices that deliver minimal switching and
routing latencies.
In this test case, test ports emulate a multicast source sending traffic to a number of
groups/channels connected to the DUT, which in turn are connected to other test ports
emulating clients that receive the multicast traffic upon sending IGMP Joins and that stop
receiving traffic as soon as they send a Leave report for any particular group. The DUT should not
forward multicast traffic until there is at least one Join for that particular group or stop sending
traffic until the last Leave report is received for that particular group. The DUT should be able to
handle multiple Join/Leave requests simultaneously without dropping traffic for any of the
groups and without increasing the Join/Leave latency, thereby enhancing the QoE for the user.
Target Users
NEMs and service providers
Target Device Under Test (DUT)
Core and access equipment
Reference
Relevance
This test case determines the speed with which the DUT can process multicast Join and Leave
messages simultaneously for multiple groups without dropping traffic. This test emulates the
real-world user behavior of changing channels.
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Version
1.0
Test Category
Access/edge
PASS
[x] Performance [x] Availability [ ] Security [x] Scale
Required Tester Capabilities
IGMP protocol emulation
Per stream latency reporting
IPTV Channel Zapping test mechanism
IPTV Channel Zapping Results Reporting Mechanism
Various type of latencies and jitter values
Command Sequencer-like capability
A reporter tool that automatically formats results by applying pre-defined templates
Topology Diagram
S p i r e n t T e s t C e n t e r P o r t 1
M u l t i c a s t
S e r v e r
D U T
S p i r e n t T e s t C e n t e r P o r t 2
S e t T o p
B o x
M u l t i c a s t
R e c e i v e r s
Test Procedure
1. Use the IPTV Test Wizard.
a. Select the Channel Zapping Test.
i. Alternately, select the Channel Verification test. The algorithm determines whether
the receiver receives the correct channel.
b. Select the Testing Environment for the test port to source multicast traffic.
i. Alternately, select the Real World Environment if there a Real Video Source
sourcing the traffic.
c. Select IPv4 or IPv6.
d. Enter the Duration of the Test.
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e. Enter the Total number of groups/channels that to create.
f. Enter the Starting Channel IP Address (class D address) and the Increment.
g. Keep the other parameters at default.
h. Select the port to send multicast traffic to the channels/groups and enter the number of
logical Channel Blocks to divide them into.
i. If already not configured, configure the emulated device (multicast server) that will
source the traffic.
i. More than one emulated device can source different types of traffic.
ii. Optionally, select the method of obtaining the Layer 3 address for the emulated
devices – e.g., DHCP, PPPoX, L2TP.
j. Divide the number of channels/groups entered in STEP E into the logical channel block
count entered in STEP H. Each association should have at least one channel/group.
k. Configure the multicast clients by adding the devices using the Device Wizard.
l. Optionally, these clients can also have DHCP, PPPoX or L2TP emulation running for
getting the Layer 3 address.
m. Select the devices to use as multicast receivers and enable the appropriate IGMP/MLD
protocol.
n. Configure the client behavior parameters per device – how the emulated user will surf
through the channels and some default values.
o. Select the Save Timestamps checkbox for ALL the devices.
p. Finish the Wizard.
2. Upon completing the wizard, the Command Sequencer is automatically configured with the
appropriate commands.
3. Start the Command Sequencer and let the test run.
4. Upon completion of the run, the Spirent Results Report automatically pops up and displays
the results.
5. End of test.
Control Variables & Relevance
Variable Relevance Default Value
Number of
Channels/Groups
Total number of channels that the client can access. 32
Time Duration The longer the test, the more stress on the DUT. 5 minutes
Client Behavior
profile
Various parameters in the client behavior profile that can
be adjusted to exert more stress on the DUT.
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Key Measured Metrics
Matric Relevance Metric Unit
Min, Max and Avg Join
Latency
Time for the DUT to forward multicast traffic after the
first Join message is received.
Milliseconds
Min, Max and Avg.
Leave Latency
Time for the DUT to stop forwarding multicast traffic
after it receives the last Leave message.
Milliseconds
Min, Max and Avg.
Overlap Latency
Overlap in channels. Milliseconds
Min, Max and Avg.
Gap Latency
Time for the DUT to stop sending one channel and start
sending the next channel.
Milliseconds
Dropped Frames per
client
Number of dropped frames for a client. Whole
number
Join fails Number of join failures –i.e. the client was unable to get
multicast group traffic.
Whole
number
Desired Result
The test shouldn’t report join or leave failures, sequencing issues (dropped, re-ordered, duplicate
packets etc.). Join/Leave and other latency values should be within the expected range.
Analysis
The test shouldn’t report join or leave failures, sequencing issues (dropped, re-ordered, duplicate
packets etc.). Join/Leave and other latency values should be within the expected range.
Analysis is done only after the test has completed. Real-time results don’t provide all the
necessary statistics. Spirent TestCenter automatically saves the results in a database that can be
opened using the Spirent TestCenter Results Reporter. The results are pre-formatted through an
existing IPTV Channel Zapping Test template. The template provides thorough information both
from the Viewer (Multicast Receiver) and the Multicast Source/Groups in Tabular and Graph
formats.
Determine whether the values are within the expected range:
Min, Max and Avg Join Latency
Min, Max and Avg. Leave Latency
Min, Max and Avg. Gap Latency
Min, Max and Avg. Overlap Latency
Min, Max and Avg. Change Latency
Duplicate Joins
Join Fails
Dropped Frames
How the values are calculated:
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ACS_007 Can the DUT successfully process 802.1x authentication
and then bind DHCP sessions
Abstract
This test determines how fast the DUT can process 802.1x authentication requests and then bind
only those DHCP sessions that successfully complete the authentication process. In this test case,
test ports emulate 802.1x and DHCP clients. The DUT authenticates and acts as the DHCP server.
The 802.1x supplicants should be successfully authenticated before the binding the DHCP
sessions.
Description
802.1x authentication methods have been available for some time and have become one of the
most used methods of authentication.
In this test case, test ports emulate 802.1x supplicants/clients and DHCP clients directly
connected to the DUT. The DUT is the Authenticator – typically, a router or an access device such
as a DSLAM – and the DHCP Server.
Target Users
NEMs and service providers
Target Device Under Test (DUT)
Core and access equipment
Reference
Relevance
This test case determines the ability of and speed with which the DUT processes 802.1x
supplicants and then binds the DHCP clients.
Version
1.0
Test Category
Access/edge
PASS
[x] Performance [x] Availability [ ] Security [x] Scale
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Required Tester Capabilities
802.1x emulation
Various 802.1x authentications types – MD5, FAST, TLS etc.
TLS certification
DHCP client emulation
Ability to emulate a real network where the DHCP stack is related to the 802.1x stack and
won’t start binding sessions unless authentication has passed
Topology Diagram
S p i r e n t T e s t C e n t e r P o r t 1
D U T
E m u l a t e d
8 0 2 . 1 x a n d
D H C P C l i e n t s
Test Procedure
1. Configure a device with both 802.1x supplicant and DHCP clients.
a. Configure the 802.1x parameters.
b. Configure 802.1x Authentication Type.
c. Configure DHCP client parameters, such as the Options list.
2. Start 802.1x emulation.
3. Start DHCP client emulation.
4. Only those DHCP sessions for which 802.1x authentication has been successfully completed
should go to a bound state.
5. Change the 802.1x authentication type and repeat from Step 2.
6. End of test.
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Control Variables & Relevance
Variable Relevance Default Value
802.1x Authentication
Type
Different authentication types have different
implications for the DUT.
MD5
DHCP client options list Requests various parameters from the DHCP server.
Key Measured Metrics
Metric Relevance Metric Unit
802.1x Authentication
State machine
Indicates whether all the supplicants successfully
completed authentication.
Authenticated
Bound DHCP client
sessions
Number of DHCP clients that successfully
authenticated and went into a bound state.
Whole
number
DHCP bind rate Rate at which the DUT can bind DHCP sessions. Sessions/sec
Desired Result
All the configured devices should successfully complete 802.1x authentication and then bind the
DHCP sessions.
Analysis
All the configured devices should successfully complete 802.1x authentication and then bind the
DHCP sessions.
Verify that the number of DHCP sessions up is equal to the number of 802.1x supplicants
authenticated and whether they are correct.
If one or some of the supplicants fails authentication, verify that the DUT is configured correctly.
Then check the state machine to see the reported error.
Changing the authentication type may affect the DHCP bind rate.
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ACS_008 Can the DUT sustain the PPPoX session setup rate
without spiking the CPU
Abstract
In this test case, Spirent TestCenter ports establish 64,000 PPPoE client sessions with the DUT
acting as the PPPoE server. During the process the DUT CPU output is constantly monitored and
graphed using Spirent Device Commander, which passes the value to the Spirent TestCenter GUI,
automating the whole process. The X-axis of the Graph shows PPPoE Session Setup Rate and the
Y-axis shows the DUT CPU Value. The DUT should maintain the session setup rate without spiking
the CPU.
Description
This is a typical service-provider scenario, constantly monitoring the DUT CPU as the number of
sessions and the session setup rate increase. As the number of broadband subscribers increases
and functionality is aggregated within a single device, service providers must test these scenarios
to assure maximum uptime.
It is important to monitor the DUT CPU in real time and automate the test so that manual
operation is not required. Spirent’s Device Commander (aka iTest) automates DUT CPU
monitoring and parses values to Spirent TestCenter ports for real-time monitoring.
Target Users
All NEMs and service providers
Target Device Under Test (DUT)
Core and access equipment
Relevance
This test case assesses DUT CPU usage under load conditions.
Version
1.0
Test Category
Testing Access/Edge
PASS
[x] Performance [x] Availability [ ] Security [x] Scale
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Required Tester Capabilities
The tester must support:
PPPoE Emulation
Spirent TestCenter Chassis
Spirent Device Commander/iTest Software
Command Sequencer type of functionality which can use the iTest API commands to fetch the
DUT CPU Values
Native graphing capabilities within the tester GUI
Topology Diagram
D U T
P P P o E C l i e n t s
S p i r e n t D e v i c e
C o m m a n d e r
S o f t w a r e
Test Procedure
1. Configure the Spirent TestCenter ports to Emulate 64,000 PPPoE sessions.
a. Keep the default Keepalive, Timers and Retry values.
b. Keep the default Session Setup and retry rates.
2. Create a test case within the Spirent Device Commander to login into the DUT and get the
DUT CPU value. The Spirent Device Commander can be invoked from within the Spirent
TestCenter GUI. This test case gives a numerical value as the result.
3. Configure the Command Sequencer to bring up the PPPoE sessions and then bring them
down.
a. Insert a command that calls the Spirent Device Commander test case defined in Step 2,
after the command that brings up the PPPoE sessions.
b. Build a real-time graph in the Results Browser that plots the DUT CPU usage values
against the PPPoE Session Setup rate.
4. Run the Command Sequencer, observe the graph and verify whether at any point the DUT
CPU usage went to a critical level, i.e. close or equal to 100%.
5. Increase the total number of PPPoE sessions until the DUT CPU usage value reaches the
maximum tolerable value.
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6. End of Test Case.
Control Variables & Relevance
Variable Relevance Default Value
Number of PPPoE
Sessions
The more the number of PPPoE sessions, it is
more stressful on the DUT
64000
Session Connect Rate Determines how fast the PADI messages are sent
out
100 sessions/sec
Max. Outstanding
Sessions
Max number of PADIs waiting for a PADO before
further PADIs are sent out
1000
Key Measured Metrics
Matric Relevance Metric Unit
Successful Session
Setup Rate
The rate at which the DUT can successfully connect
the PPPoE sessions – i.e. go through the whole state
machine and negotiation process
Sessions/sec
DUT CPU Usage Indicates the CPU Usage at any given time within
the DUT
Percentage Value –
not to exceed 100
Desired Result
The DUT should be able to connect the configured PPPoE sessions successfully with the fastest
session setup rate possible, without CPU usage going to 100%.
Analysis
The DUT should be able to connect the configured PPPoE sessions successfully with the fastest
session setup rate possible, without CPU usage going to 100%.
The goal is to find a breaking point where the DUT cannot handle the session setup rate without
the CPU reaching 100% and causing problems.
The importance of this test is to have a complete black box testing solution for service providers
and the NEMs, taking advantage of the Spirent Device Commander capabilities of automating the
process of getting DUT CPU usage and using that value within the native Spirent TestCenter GUI.
This way, the user doesn’t have to keep track of multiple scripts and or correlate timing.
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ACS_009 ALP over access with realism
Abstract
Access concentrators perform many more functions than managing access sessions. As a result,
measuring access scale has migrated from a simple up/down session count to representing the
scale of real world conditions. Without the ability to test the scale of access under real-world
conditions, essential functions of the access concentrator remain untested.
Description
Modern access concentrators act as a single point of aggregation for access. Within a DSL
deployment, users connect to DSL access multiplexers (DSLAMs) via the copper local loop. These
DSLAMs then connect to the Cisco 6400 via ATM uplinks. Across this infrastructure, service
providers have the option of deploying a number of different service models. The most basic is
end-to-end virtual circuit connections (VCCs), where user traffic remains within the ATM
switching path of the DUT.
More sophisticated models include PPPoE tunneling, where user data tunnels via Layer 2
Tunneling Protocol (L2TP) to a corporate or ISP home gateway. This scenario provides secure
access to a provider. One may also terminate PPPoE sessions within the DUT, routing into an
Internet core via the system's GigE and 10GigE. This model also allows deployment of local
content or cache servers within the point of presence (POP). In addition to managing PPPoE
Tunnels, the Device Under Test (DUT) manages QoS and firewalling functions. The modern DUT
must be resilient to instantaneous change, ensuring subscriber quality.
In this test case, test ports establish PPPoE client sessions with the DUT and send bi-directional
traffic, measure per-stream latency values, add application layer traffic and measure the per-
stream latency values again.
Target Users
Product verification, Marketing, Engineering
Target Device Under Test (DUT)
The DUT is an access concentrator (AC) that provides 1G uplinks. The DUT terminates both static
and PPPoE connections and manages QoS. The DUT should be resilient to large swings in change.
Reference
RFC 2516
RFC 4814
Relevance
The modern access concentrator terminates both static and dynamic (PPPoE) traffic while
maintaining QoS and uplinking traffic to 1G+ Ethernet. The DUT also manages change, ensuring
uptime under scale.
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Version
1.0
PASS
[x] Performance [ ] Availability [ ] Security [x] Scale
Required Tester Capabilities
The tester must have the ability to emulate real subscribers, with real application layer traffic
and generate a mix of static and dynamic traffic, utilizing QoS, RFC 4814 addressing, and
application layer traffic under varying scale condition under change.
Topology Diagram
P P P o E /
F T P / H T T P
C l i e n t s
D U T
F T P / H T T P
S e r v e r
Test Procedure
1. Add PPPoE devices on all the test ports through the Add Device wizard.
a. Check the RFC 4814 Mac Addressing scheme option.
i. Enable PPPoE Client Authentication.
ii. Choose from the available options and configure it appropriately to match the
parameters on the DUT.
2. Create Full Mesh Traffic between all the PPPoE subscribers. Add 3 different QoS classes (EF,
AF21 and BE). Keep the Frame Size fixed at 128 bytes. Optionally you can enabled iMIX
traffic with your choice of frame size and weight selection.
a. Change the Load to 100% and leave the other settings at the default value in the Traffic
Wizard
3. Go to the Wizards section and select the Application Layer Traffic Wizard. Select one test
port as the server and the other as the client and create a uni-directional link between them.
a. Build the load profile as shown below and use it for both FTP and HTTP.
b. There are default HTTP and FTP server/client profiles available which can be customized.
4. Build the Command Sequencer to do the following:
a. Bring up the PPPoE Sessions.
b. Run Bi-directional Traffic.
i. Verify per stream Max. Latency values.
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ii. Verify dropped frame, if any.
c. Start Application Layer (FTP and HTTP) Traffic.
i. Verify per stream Max. Latency values.
ii. Verify dropped frames, if any.
d. Also check the Shorter Term Avg latency values in both cases – that shows the real-time
snapshot of the DUT buffers.
e. Disconnect the PPPoE Sessions.
f. Save Results.
5. Verify in the results the Max Latency values with and without ALP traffic.
6. Scale the number of PPPoE sessions or increase the ALP Traffic to reach the max DUT
capacity before it drops packets or displays unacceptable latency values.
7. Use the Command Sequencer to automate the test and add commands to flap the PPPoE
sessions and/or add more sessions.
a. Connect the PPPoE Sessions and wait for the state to show them as Connected.
b. Click on the View Session stats button to see the IP Addresses and Lease time info.
c. Start PPPoE Traffic verify that traffic is flowing.
d. Start ALP Traffic.
e. View the Results.
8. End of Test.
Control Variables & Relevance
Variable Relevance Default Value
Number of PPPoE Sessions The more the number of PPPoE sessions, it is
more stressful on the DUT
64000
Session Connect Rate Determines how fast the PADI messages are
sent out
100 sessions/sec
Max. Outstanding Sessions Max number of PADIs waiting for a PADO
before further PADIs are sent out
1000
FTP/HTTP Client Profiles Client parameters such Default Profile
FTP/HTTP Server Profiles Server parameters Default Profile
FTP/HTTP Load Profile These profiles determine how the FTP/HTTP
traffic ramps up and down
Default Profile
QoS Values Assigned per stream – High, low and Medium High
Key Measured Metrics
Metric Relevance Metric Unit
Successful Session
Setup Rate
The rate at which the DUT can successfully
connect the PPPoE sessions – i.e. go through the
whole state machine and negotiation process
Sessions/sec
DUT CPU Usage Indicates the CPU Usage at any given time
within the DUT
Percentage Value –
not to exceed 100
Stream Latency Values The Max. Stream Latency values with and
without Application Layer Traffic
Micro-seconds
Dropped Packets Number of dropped packets – the low priority
QoS streams should start dropping packets first
in the event of congestion
Number of Packets
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Desired Result
The DUT should handle the PPPoE and the application layer traffic together without significantly
increasing per-stream latency values and/or dropping packets.
Analysis
As the hardware technologies improve, multiple device types converge into a single device with
multiple protocols/technologies running simultaniously.
This test verifies that a mix of PPPoE control/data plane traffic together with application layer
traffic such as FTP/HTTP does not significantly increase per-stream latency values and/or doesn’t
start dropping packets.
The test also verifies that the DUT QoS settings work in this load scenario and the DUT drops the
lower priority packets first in case of congestion.
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Appendix A – Telecommunications
Definitions
APPLICATION LOGIC. The computational aspects of an application, including a list of instructions that tells a
software application how to operate.
APPLICATION SERVICE PROVIDER (ASP). An ASP deploys hosts and manages access to a packaged application by
multiple parties from a centrally managed facility. The applications are delivered over networks on a
subscription basis. This delivery model speeds implementation, minimizes the expenses and risks incurred
across the application life cycle, and overcomes the chronic shortage of qualified technical personnel
available in-house.
APPLICATION MAINTENANCE OUTSOURCING PROVIDER. Manages a proprietary or packaged application from
either the customer's or the provider's site.
ASP INFRASTRUCTURE PROVIDER (AIP). A hosting provider that offers a full set of infrastructure services for
hosting online applications.
ATM. Asynchronous Transport Mode. An information transfer standard for routing high-speed, high-
bandwidth traffic such as real-time voice and video, as well as general data bits.
AVAILABILITY. The portion of time that a system can be used for productive work, expressed as a
percentage.
BACKBONE. A centralized high-speed network that interconnects smaller, independent networks.
BANDWIDTH. The number of bits of information that can move through a communications medium in a
given amount of time; the capacity of a telecommunications circuit/network to carry voice, data, and
video information. Typically measured in Kbps and Mbps. Bandwidth from public networks is typically
available to business and residential end-users in increments from 56 Kbps to 45 Mbps.
BIT ERROR RATE. The number of transmitted bits expected to be corrupted per second when two computers
have been communicating for a given length of time.
BURST INFORMATION RATE (BIR). The rate of information in bits per second that the customer may need over
and above the CIR. A burst is typically a short duration transmission that can relieve momentary
congestion in the LAN or provide additional throughput for interactive data applications.
BUSINESS ASP. Provides prepackaged application services in volume to the general business market,
typically targeting small to medium size enterprises.
BUSINESS-CRITICAL APPLICATION. The vital software needed to run a business, whether custom-written or
commercially packaged, such as accounting/finance, ERP, manufacturing, human resources and sales
databases.
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BUSINESS SERVICE PROVIDER. Provides online services aided by brick-and-mortar resources, such as payroll
processing and employee benefits administration, printing, distribution or maintenance services. The
category includes business process outsourcing (BPO) companies.
COMMERCE NETWORK PROVIDER. Commerce networks were traditionally proprietary value-added networks
(VANs) used for electronic data interchange (EDI) between companies. Today the category includes the
new generation of electronic purchasing and trading networks.
COMPETITIVE ACCESS PROVIDER (CAP). A telecommunications company that provides an alternative to a LEC
for local transport and special access telecommunications services.
CAPACITY. The ability for a network to provide sufficient transmitting capabilities among its available
transmission media, and respond to customer demand for communications transport, especially at peak
usage times.
CLIENT/DEVICE. Hardware that retrieves information from a server.
CLUSTERING. A group of independent systems working together as a single system. Clustering technology
allows groups of servers to access a single disk array containing applications and data.
COMPUTING UTILITY PROVIDER (CUP). A provider that delivers computing resources, such as storage, database
or systems management, on a pay-as-you-go basis.
CSU/DSU. Channel Server Unit/Digital Server Unit. A device used to terminate a telephone company
connection and prepare data for a router interface.
DATA MART. A subset of a data warehouse, intended for use by a single department or function.
DATA WAREHOUSE. A database containing copious amounts of information, organized to aid decision-
making in an organization. Data warehouses receive batch updates and are configured for fast online
queries to produce succinct summaries of data.
DEDICATED LINE. A point-to-point, hardwired connection between two service locations.
DEMARCATION LINE. The point at which the local operating company's responsibility for the local loop ends.
Beyond the demarcation point (also known as the network interface), the customer is responsible for
installing and maintaining all equipment and wiring.
DISCARD ELIGIBILITY (DE) BIT. Relevant in situations of high congestion, it indicates that the frame should be
discarded in preference to frames without the DE bit set. The DE bit may be set by the network or by the
user; and once set cannot be reset by the network.
DS-1 OR T-1. A data communication circuit capable of transmitting data at 1.5 Mbps. Currently in
widespread use by medium and large businesses for video, voice, and data applications.
DS-3 OR T-3. A data communications circuit capable of transmitting data at 45 Mbps. The equivalent data
capacity of 28 T-1s. Currently used only by businesses/institutions and carriers for high-end applications.
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ELECTRONIC DATA INTERCHANGE (EDI). The electronic communication of business transactions (orders,
confirmations, invoices etc.) of organizations with differing platforms. Third parties provide EDI services
that enable the connection of organizations with incompatible equipment.
ENTERPRISE ASP. An ASP that delivers a select range of high-end business applications, supported by a
significant degree of custom configuration and service.
ENTERPRISE RELATIONSHIP MANAGEMENT (ERM). Solutions that enable the enterprise to share comprehensive,
up-to-date customer, product, competitor and market information to achieve long-term customer
satisfaction, increased revenues, and higher profitability.
ENTERPRISE RESOURCE PLANNING (ERP). An information system or process integrating all manufacturing and
related applications for an entire enterprise. ERP systems permit organizations to manage resources
across the enterprise and completely integrate manufacturing systems.
ETHERNET. A local area network used to connect computers, printers, workstations, and other devices
within the same building. Ethernet operates over twisted wire and coaxial cable.
EXTENDED SUPERFRAME FORMAT. A T1 format that provides a method for easily retrieving diagnostics
information.
FAT CLIENT. A computer that includes an operating system, RAM, ROM, a powerful processor and a wide
range of installed applications that can execute either on the desktop or on the server to which it is
connected. Fat clients can operate in a server-based computing environment or in a stand-alone fashion.
FAULT TOLERANCE. A design method that incorporates redundant system elements to ensure continued
systems operation in the event of the failure of any individual element.
FDDI. Fiber Distributed Data Interface. A standard for transmitting data on optical-fiber cables at a rate of
about 100 Mbps.
FRAME. The basic logical unit in which bit-oriented data is transmitted. The frame consists of the data bits
surrounded by a flag at each end that indicates the beginning and end of the frame. A primary rate can be
thought of as an endless sequence of frames.
FRAME RELAY. A high-speed packet switching protocol popular in networks, including WANs, LANs, and
LAN-to-LAN connections across long distances.
GBPS. Gigabits per second, a measurement of data transmission speed expressed in billions of bits per
second.
HOSTED OUTSOURCING. Complete outsourcing of a company's information technology applications and
associated hardware systems to an ASP.
HOSTING PROVIDER. Provider who operates data center facilities for general-purpose server hosting and
collocation.
INFRASTRUCTURE ISV. And independent software vendor that develops infrastructure software to support
the hosting and online delivery of applications.
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INTEGRATED SERVICES DIGITAL NETWORK (ISDN). An information transfer standard for transmitting digital voice
and data over telephone lines at speeds up to 128 Kbps.
INTEGRATION. Equipment, systems, or subsystem integration, assembling equipment or networks with a
specific function or task. Integration is combining equipment/systems with a common objective, easy
monitoring and/or executing commands. It takes three disciplines to execute integration: 1) hardware, 2)
software, and 3) connectivity – transmission media (data link layer), interfacing components. All three
aspects of integration have to be understood to make two or more pieces of equipment or subsystems
support the common objective.
INTER-EXCHANGE CARRIER (IXC). A telecommunications company that provides telecommunication services
between local exchanges on an interstate or intrastate basis.
INTERNET SERVICE PROVIDER (ISP). A company that provides access to the Internet for users and businesses.
INDEPENDENT SOFTWARE VENDOR (ISV). A company that is not a part of a computer systems manufacturer
that develops software applications.
INTERNETWORKING. Sharing data and resources from one network to another.
IT SERVICE PROVIDER. Traditional IT services businesses, including IT outsourcers, systems integrators, IT
consultancies and value added resellers.
KILOBITS PER SECOND (KBPS). A data transmission rate of 1,000 bits per second.
LEASED LINE. A telecommunications line dedicated to a particular customer along predetermined routers.
LOCAL ACCESS TRANSPORT AREA (LATA). One of approximately 164 geographical areas within which local
operating companies connect all local calls and route all long-distance calls to the customer's inter-
exchange carrier.
LOCAL EXCHANGE CARRIER (LEC). A telecommunications company that provides telecommunication services
in a defined geographic area.
LOCAL LOOP. The wires that connect an individual subscriber's telephone or data connection to the
telephone company central office or other local terminating point.
LOCAL/REGIONAL ASP. A company that delivers a range of application services, and often the complete
computing needs, of smaller businesses in their local geographic area.
MEGABITS PER SECOND (MBPS). 1,024 kilobits per second.
METAFRAME. The world's first server-based computing software for Microsoft Windows NT 4.0 Server,
Terminal Server Edition multi-user software (co-developed by Citrix).
MODEM. A device for converting digital signals to analog and vice versa, for data transmission over an
analog telephone line.
MULTIPLEXING. The combining of multiple data channels onto a single transmission medium. Sharing a
circuit - normally dedicated to a single user - between multiple users.
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MULTI-USER. The ability for multiple concurrent users to log on and run applications on a single server.
NET-BASED ISV. An ISV whose main business is developing software for Internet-based application services.
This includes vendors who deliver their own applications online, either directly to users or via other
service providers.
NETWORK ACCESS POINT (NAP). A location where ISPs exchange traffic.
NETWORK COMPUTER (NC). A thin-client hardware device that executes applications locally by downloading
them from the network. NCs adhere to a specification jointly developed by Sun, IBM, Oracle, Apple and
Netscape. They typically run Java applets within a Java browser, or Java applications within the Java
Virtual Machine.
NETWORK COMPUTING ARCHITECTURE. A computing architecture in which components are dynamically
downloaded from the network onto the client device for execution by the client. The Java programming
language is at the core of network computing.
ONLINE ANALYTICAL PROCESSING (OLAP). Software that enables decision support via rapid queries to large
databases that store corporate data in multidimensional hierarchies and views.
OPERATIONAL RESOURCE PROVIDER. Operational resources are external business services that an ASP might
use as part of its own infrastructure, such as helpdesk, technical support, financing, or billing and payment
collection.
OUTSOURCING. The transfer of components or large segments of an organization's internal IT infrastructure,
staff, processes or applications to an external resource such as an ASP.
PACKAGED SOFTWARE APPLICATION. A computer program developed for sale to consumers or businesses,
generally designed to appeal to more than a single customer. While some tailoring of the program may be
possible, it is not intended to be custom-designed for each user or organization.
PACKET. A bundle of data organized for transmission, containing control information (destination, length,
origin, etc.), the data itself, and error detection and correction bits.
PACKET SWITCHING. A network in which messages are transmitted as packets over any available route rather
than as sequential messages over circuit-switched or dedicated facilities.
PEERING. The commercial practice under which nationwide ISPs exchange traffic without the payment of
settlement charges.
PERFORMANCE. A major factor in determining the overall productivity of a system, performance is primarily
tied to availability, throughput and response time.
PERMANENT VIRTUAL CIRCUIT (PVC). A PVC connects the customer's port connections, nodes, locations, and
branches. All customer ports can be connected, resembling a mesh, but PVCs usually run between the
host and branch locations.
POINT OF PRESENCE (POP). A telecommunications facility through which the company provides local
connectivity to its customers.
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PORTAL. A company whose primary business is operating a Web destination site, hosting content and
applications for access via the Web.
REMOTE ACCESS. Connection of a remote computing device via communications lines such as ordinary
phone lines or wide area networks to access distant network applications and information.
REMOTE PRESENTATION SERVICES PROTOCOL. A set of rules and procedures for exchanging data between
computers on a network, enabling the user interface, keystrokes, and mouse movements to be
transferred between a server and client.
RESELLER/VAR. An intermediary between software and hardware producers and end users. Resellers
frequently add value (thus Value-Added Reseller) by performing consulting, system integration and
product enhancement.
ROUTER. A communications device between networks that determines the best path for optimal
performance. Routers are used in complex networks of networks such as enterprise-wide networks and
the Internet.
SCALABILITY. The ability to expand the number of users or increase the capabilities of a computing solution
without making major changes to the systems or application software.
SERVER. The computer on a local area network that often acts as a data and application repository and that
controls an application's access to workstations, printers and other parts of the network.
SERVER-BASED COMPUTING. A server-based approach to delivering business-critical applications to end-user
devices, whereby an application's logic executes on the server and only the user interface is transmitted
across a network to the client. Benefits include single-point management, universal application access,
bandwidth-independent performance, and improved security for business applications.
SINGLE-POINT CONTROL. One of the benefits of the ASP model, single-point control helps reduce the total
cost of application ownership by enabling widely used applications and data to be deployed, managed
and supported at one location. Single-point control enables application installations, updates and
additions to be made once, on the server, which are then instantly available to users anywhere.
SPECIALIST ASP. Provide applications which serve a specific professional or business activity, such as
customer relationship management, human resources or Web site services.
SYSTEMS MANUFACTURER. Manufacturer of servers, networking and client devices.
TELECOMS PROVIDER. Traditional and new-age telecommunications network providers (telcos).
THIN CLIENT. A low-cost computing device that accesses applications and and/or data from a central server
over a network. Categories of thin clients include Windows-Based Terminals (WBT, which comprise the
largest segment), X-Terminals, and Network Computers (NC).
TOTAL COST OF OWNERSHIP (TCO). Model that helps IT professionals understand and manage the budgeted
(direct) and unbudgeted (indirect) costs incurred for acquiring, maintaining and using an application or a
computing system. TCO normally includes training, upgrades, and administration as well as the purchase
price. Lowering TCO through single-point control is a key benefit of server-based computing.
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TOTAL SECURITY ARCHITECTURE (TSA). A comprehensive, end-to-end architecture that protects the network.
TRANSMISSION CONTROL PROTOCOL/INTERNET PROTOCOL (TCP/IP). A suite of network protocols that allow
computers with different architectures and operating system software to communicate over the Internet.
USER INTERFACE. The part of an application that the end user sees on the screen and works with to operate
the application, such as menus, forms and buttons.
VERTICAL MARKET ASP. Provides solutions tailored to the needs of a specific industry, such as the healthcare
industry.
VIRTUAL PRIVATE NETWORK (VPN). A secure, encrypted private connection across a cloud network, such as
the Internet.
WEB HOSTING. Placing a consumer's or organization's web page or web site on a server that can be
accessed via the Internet.
WIDE AREA NETWORK. Local area networks linked together across a large geographic area.
WINDOWS-BASED TERMINAL (WBT). Thin clients with the lowest cost of ownership, as there are no local
applications running on the device. Standards are based on Microsoft's WBT specification developed in
conjunction with Wyse Technology, NCD, and other thin client companies.
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Appendix B – Layer 2 802.1q CoS
The following tables represent best practices for Layer 2 VLAN / Q-in-Q CoS. Each row relates the
appropriate metric to measured minimum acceptable for its respective traffic class.
VLAN 802.1p CoS / Q-in-Q Priority
802.1 PRI
CoS
Min. RX / TX
Bandwidth
Ratio
Max
Jitter
(uSec)
Max
Latency
(uSec)
Max
Loss
(Frames)
Max
Duplicate
(Frames)
Max
Reordered
(Frames)
Max
Late
(Frames)
7 1 0 >=1 0 0 0 0
6 1 0 2 0 0 0 0
5 .99 1 2 0 0 0 0
4 .98 1 3 0 0 0 0
3 .95 2 5 0 1 1 1
2 .90 3 5 1 1 1 1
1 .85 5 10 1 2 2 2
0 ANY ANY ANY ANY ANY ANY ANY
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Appendix C – RFC 2474 Layer 3 QoS
The following tables represent best practices for Layer 2 VLAN / Q-in-Q CoS. Each row relates the
appropriate metric to measured minimum acceptable for its respective traffic class.
IPv4 / IPv6 DiffServ
Codepoint Max Jitter
(uSec)
Max
Latency
(uSec)
Max Loss
(Frames)
Max
Duplicate
(Frames)
Max
Reordered
(Frames)
Max Late
(Frames)
EF 0 >=1 0 0 0 0
AF31 0 2 0 0 0 0
AF21 2 5 0 1 1 1
AF11 3 5 1 1 1 1
BE ANY ANY ANY ANY ANY ANY
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Appendix D – RFC 2474 Layer 3 QoS
Definitions
The following table represents the definitions of each DiffServ Codepoint possibility.
DSCP Value DF Code
Point
Equivalent IP
Precedent
Description
000 000 00 BE 000 - Routine Best Effort, Unclassified Quality
001 010 10 AF11 001 - Priority High-Throughput Transactions with high loss
sensitivity
001 100 12 AF12 001 - Priority High-Throughput Transactions with some loss
sensitivity
001 110 14 AF13 001 - Priority High-Throughput Transactions with loss
resiliency
001 010 18 AF21 001 - Immediate Low-Latency Transactions with high loss
sensitivity
010 100 20 AF22 001 - Immediate Low-Latency Transactions with some loss
sensitivity
010 119 22 AF23 001 - Immediate Low-Latency Transaction with loss resiliency
011 010 26 AF31 011 - Flash Broadcast Media with high loss sensitivity
011 110 28 AF32 011 - Flash Broadcast Media with some loss sensitivity
011 110 30 AF33 001 - Flash Broadcast Media with loss resiliency
100 010 34 AF41 100 – Flash Override Live Media with high loss sensitivity
100 110 36 AF42 100 – Flash Override Live Media with some loss sensitivity
100 110 38 AF43 100 – Flash Override Live Media with loss resiliency
101 110 46 EF 101 – Critical Mission Critical Transactions or VoIP
