Spirent TestCenterSegment Routing AppNote

Application Note

Table of contents

Executive Summary � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �2

Overview of Segment Routing � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �2

Using Spirent TestCenter with Segment Routing � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �3

Test case – IS-IS Segment Routing Basic � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �4

Overview� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �4

Objective� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �4

Configuring the test - DUT � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �4

Configuring the test - Spirent TestCenter� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � �5

Executing the test and Analyzing the results� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 15

Test Parameters � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 15

Test case – IS-IS Segment Routing with VPN � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 16

Overview� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 16

Objective� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 16

Configuring the test - DUT � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 16

Configuring the test - Spirent TestCenter� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 17

Executing the test and Analyzing the results� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 22

Test Parameters � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 23

Troubleshooting� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 23

Test case – OSPFv2 Segment Routing Basic � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 24

Overview� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 24

Objective� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 24

Configuring the test - DUT � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 24

Configuring the test - Spirent TestCenter� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 25

Executing the test and Analyzing the results� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 40

Test Parameters � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 41

Troubleshooting� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 42

Test case – OSPFv2 Segment Routing Explicit Path � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 43

Overview� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 43

Objective� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 43

Configuring the test - DUT � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 43

Configuring the test - Spirent TestCenter� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 44

Executing the test and Analyzing the results� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 65

Test Parameters � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 69

Troubleshooting� � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 70

Acronyms � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � � 70

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Application Note

Executive SummarySDN (Software-defined Network), an emerging architecture which decouples the network control-plane and data-plane, provides an ideal solution

for today’s network services and applications which are demanding high-bandwidth, dynamic updates and low costs� SDN logically centralizes the

network intelligence, let the network administrator programmatically configure and optimize network resource dynamically�

Segment routing (SR) is a concept that’s been working its way through the IETF standards process but is finally becoming ready for real world

deployment� It’s a network technology that provides enhanced packet forwarding behavior while minimizing the need for maintaining awareness of

mass volumes of network state�

This document provides an overview of Segment Routing for IS-IS and OSPFv2 extensions and describes how Spirent TestCenter is used to validate

customers’ related products� Several use cases are given and step-by-step instructions on using Spirent TestCenter to configure and run these test

cases are described in detail�

The target audiences of this document are who need to use Spirent TestCenter to test products – like system test, integration test and product

development engineers�

Overview of Segment RoutingSegment Routing (SR) leverages the source routing and tunneling paradigms� It allows for a flexible definition of end-to-end paths within topologies

by encoding paths as sequences of topological sub-paths, called “segments”� A segment can represent any instruction, topological or service-based�

These segments can be advertised by OSPF or IS-IS protocol� The advertised segments are finally translated to MPLS labels, and the data packets are

forwarded by label switching�

For example, in the following topology, every router is assigned a unique Node-SID value� The IGP metric of the link between Router 2 and Router 3

is 10, and that between Router 2 and Router 4 is 15� The first packet send from Router 1 to 1�1�1�99 has label 99, and 99 is the Node-SID of 1�1�1�99� Every

router on the shortest path will swap the labels till it reaches the destination� The packet chooses the link between R2 and R3 instead of R2 and R4

because it is on the shortest path�

If you want the packet choose a specific path, for example, through Router 4, the packet should has the label of 99 and 40�

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The following aspects need to be validated for a DUT�

1� After receiving the routes with SR information, which are sub TLVs of extended LSA for OSPF or LSP for IS-IS, DUT should form correct MPLS

forwarding table� Complex topology configuration needs effort to configure routes, node SID, prefix SID, adjacency SID, SR capability etc� and

error-prone�

2� Need to validate if the packet is forwarded on the expected path�

3� Need to validate it in multi-protocol scenario, such as VPN�

4� Performance test�

Using Spirent TestCenter with Segment RoutingSpirent TestCenter supports IS-IS and OSPFv2 Segment Routing extensions� And it now supports the following testing with segment routing:

� Device Wizard and LSA/LSP Generator Wizards

� L2VPN and L3VPN Wizards

� NextHop Lookup

� BGP short-cut

� IS-IS Mapping Server

� Automatic Segment Routing Label Management

Spirent TestCenter provides LSA/LSP Generator Wizard to generate large scale routes and complex topology� The corresponding sub-TLVs are

inserted to the proper position of the LSA/LSPs and proper SIDs are auto configured� The wizard saves customer’s configuration effort and eliminates

the possibility of misconfiguration� Besides the wizard, user also has the ability to create and fine tune every single sub TLV�

Spirent TestCenter uses a simple and intuitive way to validate SR function� Usually a stream is created with source and destination configured, and

then the protocol used to resolve the labels is specified� After the routes are exchanged, the stream should be resolved, and the packets with correct

labels should be captured from the destination Spirent TestCenter port� This validation can be executed manually or automated by a few commands�

Four test cases are included in the doc to help user learning Spirent TestCenter Segment Routing:

1� IS-IS Segment Routing Basis

2� IS-IS Segment Routing for L3VPN

3� OSPFv2 Segment Routing Basic

4� OSPFv2 Segment Routing Explicit Path

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Application Note

Test case – IS-IS Segment Routing BasicOverview

This scenario describes the basic use case for IS-IS Segment Routing� It requires 2 Spirent TestCenter ports and 2 DUT ports as shown in the following

diagram� And it requires DUT to support the following functions:

� IS-IS Segment Routing extensions with Prefix SID support

� Segment Routing data plane (MPLS forwarding)

IS-IS segment routing is enabled on the devices under these 2 Spirent TestCenter ports and LSPs with SR information are exchanged between DUT

and Spirent TestCenter� A stub network 78�1�1�0/24 is advertised from Spirent TestCenter port B to DUT� A bound stream with destination configured as

78�1�1�2 is created under Spirent TestCenter port A�

Objective

The test is to perform basic data plane and control plane functional verification for IS-IS Segment Routing Routers�

Configuring the test - DUT

1� Connect cable between Spirent TestCenter port A/B and DUT�

2� On DUT, configure the IP addresses of the 2 ports as 100�0�0�1/24 and 101�0�0�1/24�

3� On DUT, configure the loop back address as 1�1�1�1 and enable segment routing�

4� On DUT, configure a SID base/range as 1000/100�

5� On DUT, configure SID for prefix 1�1�1�1/32 to 30 and set the N flag�

6� On DUT, enable IS-IS on 100�0�0�1/24 and 101�0�0�1/24 in back-bone area (area 0)�

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Configuring the test - Spirent TestCenter

1� Start Spirent TestCenter GUI, connect the Spirent TestCenter chassis and reserve Spirent TestCenter port A and port B�

2� In All Devices View, create 1 device on each of the 2 ports and enable IS-IS on the devices via the wizard

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3� After clicking the Finish button, IS-IS LSP Generator wizard is launched�

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4� Select All Devices node in the left navigator panel, All Devices Grid view is shown in the content area� Goes to IS-IS tab (Use Technologies

Selector to enable IS-IS if the tab is not present)� Click Edit LSPs/IIHs… tool bar menu to check if the routes and SR related TLVs are created as

expected�

5� Now add the route 78�1�1�0/24 on the second device� Select the second device and click Edit LSPs/IIHs tool bar menu:

� Go to the IPv4 Routes tab, and click Add button to add an IPv4 route�

� Clicking Add Prefix SID Sub-TLV button to add a Prefix SID Sub-TLV�

� Change the parameters as shown in the picture�

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6� In All Stream Blocks view, create stream to 78�1�1�2,

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Executing the test and Analyzing the results

1� Click Start All Device button , Spirent TestCenter and DUT will start to establish adjacency and exchange routes� You can tell if the process is

successfully finished by checking the Router State in the IS-IS result view�

2� At this point, check the status of the stream� The icon in front of the stream should change to green which indicates the prefix or adjacency is

resolved� Now start the capture , and start the traffic � On the second Spirent TestCenter port, the packets send from the first Spirent

TestCenter port and passing through the DUT should be captured�

3� To check if the label is resolved correctly, you can edit the stream and go the Preview tab, check the option of Show Resolved Encapsulations�

The above steps can be automated with Command Sequencer�

Test Parameters

Usually, you can change Capability TLVs which specify the Start and Range of the SID pool or SID for prefix, adjacency� The change impacts the

resolved label, and then re-run the test to see if the change takes effect�

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Application Note

Test case – IS-IS Segment Routing with VPNOverview

This scenario describes the application of IS-IS SR in VPN� It requires 2 SpirentTestCenter ports and 2 DUT ports as the following diagram shown�

And it requires DUT to support the following functions:

� IS-IS Segment Routing extensions

� Segment Routing data plane (MPLS forwarding)

� BGP VPN

The left side to the DUT is the provider side port, and two devices are created under it to act as PE router which is BGP enabled and P router which

is IS-IS enabled respectively� P and PE router are connected via VRF Provider Link� Two IS-IS LSPs are created on P router, one is for itself and one is

used to simulate PE router� A VPN route 192�0�1�0/24 is configured on PE router�

The right side to the DUT is the customer side port� A CE device which is BGP enabled is created under the second Spirent TestCenter port� And a

VPN route 193�0�1�0/24 is created on it� 192�0�1�0/24 and 193�0�1�0/24 belong to the same VPN� A bi-directional traffic is created to verify the SR SIDs are

distributed, MPLS label is calculated and switched correctly�

Objective

The test is to perform basic data plane and control plane functional verification for IS-IS Segment Routing PE Routers as L3VPN label protocol�

Configuring the test - DUT

1� Connect cable between the two Spirent TestCenter ports and DUT�

2� On DUT, configure the IP addresses of the 2 ports as 20�0�0�2/24 and 220�1�1�10/24�

3� On DUT, configure the loop back address as 1�1�1�1 and enable segment routing

4� On DUT, configure a SID base/range as 100/100

5� On DUT, configure SID for prefix 1�1�1�1/32 to 30 and the set the N flag�

6� On DUT, enable IS-IS on 20�0�0�2/24�

7� On DUT, configure BGP VPNv4 session with 10�0�0�2; configure BGP VPN-instance session with 220�1�1�0�

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Configuring the test - Spirent TestCenter

1� Start Spirent TestCenter GUI, connect the Spirent TestCenter chassis and reserve Spirent TestCenter port 1 and port 2�

2� Launch the MPLS IP VPN wizard�

It is located in the following path of the wizard tree�

Routing and MPLS/MPLS/MPLS IP VPN

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Application Note

3� Configure the Provider side port

4� Click options button besides IS-IS SR protocol to configure SR related sub TLVs�

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5� Configure the customer side port

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6� Configure the VPN

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7� Configure the VPN routes

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Application Note

8� Create the traffic

Executing the test and Analyzing the results

1� Start IS-IS on P router� Right click the P router in the device grid view, and select IS-IS/Start IS-IS from the context menu� Check router state in the

IS-IS result view�

2� Start BGP on PE router� Right click the PE router in the device grid view and select BGP/Start BGP from the context menu� Check router state in

the BGP result view�

3� After the routes are exchanged successfully, the stream status will change to resolved and the icon in front of the stream change to green�

4� To check if the label is resolved correctly, you can edit the stream and go the Preview tab, check the option of Show Resolved Encapsulations�

5� Now start the capture , and start the traffic �

For the traffic from 193�0�1�0 to 192�0�10, capture packets from the provider side port and to see if the correct MPLS label is encapsulated by DUT�

Label 16 is for BGP VPN and IS-IS SR label 110 for PE router�

For the traffic from 192�0�1�0 to 193�0�10, VPN label assigned by DUT should be observed and IS-IS SR label should be 130� This needs to be done

on DUT�

The above steps can be automated with Command Sequencer�

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Test Parameters

Usually, you can change Capability TLVs which specify the Start and Range of the SID pool or SID for prefix, and then re-run the test to see if the

change takes effect�

You can increase the route number of the route block to do the large scale test�

Spirent TestCenter route generator wizard can generate complex and large-scale topologies which stress the DUT�

Troubleshooting

1� Check the stream and make sure the label resolver is configured properly� If it is not set, click Auto Select Bindings�

2� If there is no label resolver available for IS-IS SR, please check if the SR TLVs are configured properly�

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Application Note

Test case – OSPFv2 Segment Routing BasicOverview

This scenario describes the basic use cases for OSPFv2 Segment Routing� It requires 2 Spirent TestCenter ports and 2 DUT ports as the following

diagram shows� And it requires DUT to support the following functions:

� OSPFv2 Segment Routing extensions with Prefix SID support

� Segment Routing data plane (MPLS forwarding)

In the scenario, the 2 Spirent TestCenter ports will enable OSPFv2 segment routing and exchange SID information with DUT� Spirent TestCenter port B

advertises a stub network 78�1�1�0/24 to DUT and Spirent TestCenter port A� Spirent TestCenter port A has a bound stream which destination is 78�1�1�2�

Objective

The test is to perform basic data plane and control plane functional verification for OSPFv2 Segment Routing Routers�

Configuring the test - DUT

1� Connect cable with Spirent TestCenter port A/B with DUT�

2� On DUT, configure the IP addresses of the 2 ports as 100�0�0�1/24 and 101�0�0�1/24�

3� On DUT, configure Router ID of OSPFv2 to 1�1�1�1 and enable segment routing�

4� On DUT, configure a SID base/range as 1000/100�

5� On DUT, configure prefix SID of 1�1�1�1/32 as index 1�

6� On DUT, Enable OSPFv2 on 100�0�0�1/24 and 101�0�0�1/24 in back-bone area (area 0)�

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Configuring the test - Spirent TestCenter

1� Start Spirent TestCenter GUI, connect the Spirent TestCenter chassis and reserve Spirent TestCenter port A and port B�

2� In All Devices View, create 1 device on each of the 2 ports by clicking “Add…” button; the wizard steps are as following�

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Application Note

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3� In All Devices Grid view, change Router ID to 1�1�1�2 and 1�1�1�3�

4� In All Devices Grid view, goes to OSPFv2 tab (If not existed in your GUI, use Technologies Selector to enable OSPFv2), and then active OSPFv2

on the 2 devices�

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Application Note

5� In OSPFv2 Tab, the default area ID of the 2 router should be 0�0�0�0; change the Options to support Opaque LSA�

6� In OSPFv2 Tab, Use LSA Generator to create LSAs for router 1�1�1�2; the wizard steps are the following�

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Application Note

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Application Note

7� In OSPFv2 Tab, Use LSA Generator to create LSAs for router 1�1�1�3�

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Application Note

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Application Note

8� Verify LSA configuration on device 1�1�1�3; add prefix SID for 78�1�1�0/24�

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9� In All Stream Blocks view, create stream to 78�1�1�2�

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Application Note

10� Set the label resolver to “OSPFv2 SR Router 1�1�1�3”�

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Application Note

Executing the test and Analyzing the results

1� Start device 1�1�1�2 and 1�1�1�3, and wait until their Adjacency Status changes to Full�

2� Check the status of stream block, it should be resolved now (green light)�

3� Check the MPLS forwarding table of DUT, it should have an item for 1�1�1�3/32 with label 1003 and 78�1�1�0/24 with label 1004�

4� Start the stream block, and then capture on router 1�1�1�3�

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5� Check the captured stream, it should include the label 1004 in MPLS header�

Test Parameters

1� Change the SID index for 78�1�1�0/24 to 13, re-apply, start devices and stream, then check MPLS forwarding table of DUT� You will see label for

78�1�1�0/24 changes from 1004 to 1013�

2� Change Extended Prefix TLV to Extended Prefix Range TLV, and then create new stream block, the single stream can be easily changed to

multiple streams�

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Application Note

Troubleshooting

1� If OSPFv2 router cannot get to Full status, try to change the priority of OSPF router from 0 to other priorities�

2� If the steam cannot be resolved, check the LSDB on DUT� The all LSAs generated by Spirent TestCenter port A and B should exist in LSDB

3� If Spirent TestCenter port B cannot receive the stream, check the MPLS forwarding table on DUT� The 78�1�1�0/24 should exist and have correct

label�

4� If the label of the stream is not 1004 or other unexpected labels, check the base/range SID on DUT�

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Test case – OSPFv2 Segment Routing Explicit PathOverview

This scenario describes the use case for OSPFv2 Segment Routing explicit path� It requires 3 Spirent TestCenter ports and 3 DUT ports as the

following diagram shows� And it requires DUT to support the following functions:

� OSPFv2 Segment Routing extensions with Prefix and Adjacency SID support

� Segment Routing data plane (MPLS forwarding)

In the scenario, DUT has 2 east links with Spirent TestCenter port C and D� Spirent TestCenter emulates router C and router D and they both have

connection with simulated router E� Router E has a stub network 79�1�1�0/24� All Spirent TestCenter emulated/simulated routers enable OSPFv2

segment routing and exchange SID information with DUT�

Spirent TestCenter port A has 2 bound streams with destination 79�1�1�2� One of the streams – stream A has single label to destination prefix; the other

– stream B has explicit path with 3 layers of label and the adjacency 9002 is included�

Since the cost of link 9001 is lower than link 9002 of DUT, stream A will pass though Spirent TestCenter emulated router C but stream B will pass

through router D�

Objective

The test is to perform basic data plane and control plane functional verification for OSPFv2 Segment Routing Routers with the capacity of explicit path

(adjacency label)�

Configuring the test - DUT

1� Connect cable with Spirent TestCenter port A/C/D with DUT�

2� On DUT, configure the IP addresses of the 3 ports as 100�0�0�1/24, 110�0�0�1/24 and 111�0�0�1/24�

3� On DUT, configure Router ID of OSPFv2 to 1�1�1�1, enable segment routing and turn off PHP�

4� On DUT, configure a SID base/range as 1000/100�

5� On DUT, configure prefix SID of 1�1�1�1/32 as index 1�

6� On DUT, enable OSPFv2 on 100�0�0�1/24, 110�0�0�1/24 and 111�0�0�1/24 in back-bone area (area 0)�

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Application Note

Configuring the test - Spirent TestCenter

1� Start Spirent TestCenter GUI, connect the Spirent TestCenter chassis and reserve Spirent TestCenter port A, port B and port C�

2� In All Devices View, create 1 device/router/LSAs for router A�

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Application Note

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Application Note

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Application Note

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3� In All Devices View, create 1 device/router/LSAs for router C and D�

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Application Note

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Application Note

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Application Note

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4� Since above wizard generated simulated router 1�1�1�12 and 1�1�1�13, we need to change 1�1�1�13 back to 1�1�1�12 manually� Open “Edit LSAs” dialog for

router 1�1�1�11 and make modification in Router LSA, Opaque/Router Info LSAs, Opaque/SR Ext Prefix LSAs and Opaque/SR Ext Link LSAs tabs�

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Application Note

5� Add stub network 79�1�1�0/24 to router 1�1�1�12 for port C and port D�

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6� In All Steam Blocks view, Create IGP determined path�

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Application Note

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7� In All Steam Blocks view, Create Explicit path�

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Application Note

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Application Note

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Executing the test and Analyzing the results

1� Start device 1�1�1�2, 1�1�1�10 and 1�1�1�11, and wait until their Adjacency Status changes to Full�

2� Check the status of stream blocks, they should be both resolved now (green light)�

3� Check the resolved label for the first stream block, it should be 1013�

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Application Note

4� Check the resolved label for the second stream block, it should have 3 labels which are 1001, 9002 and 1013�

5� Check the MPLS forwarding table of DUT, it should have an item for 1�1�1�10/32 with label 1010, 1�1�1�11/32 with label 1011 and 79�1�1�0/24 with

label 1013�

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6� Start the first stream block, and then capture on router 1�1�1�10�

7� Check the captured the packets, it should include the label 1013 in MPLS header�

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Application Note

8� Start the second stream block, and then capture on router 1�1�1�11�

9� Check the captured packets, and it should include the label 1013 in MPLS header because label 1001 and label 9002 have been popped

up by DUT�

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Test Parameters

1� Change the SID index for 79�1�1�0/24 to 23, re-apply, start devices and stream, then check MPLS forwarding table of DUT� You will see label for

79�1�1�0/24 changes from 1013 to 1023�

2� Change the layer 2 of Label binding link ID from 1�1�11 to 1�1�1�10, re-apply, start the stream, router 1�1�1�11 should not be able to receive any packets�

Instead, router 1�1�1�10 should receive the stream�

© 2016 Spirent. All Rights Reserved.

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 of Spirent plc and its subsidiaries, pending registration in

accordance with relevant national laws. All other registered trademarks or trademarks are the property of their respective owners.

The information contained in this document is subject to change without notice and does not represent a commitment on the part

of Spirent. The information in this document is believed to be accurate and reliable; however, Spirent assumes no responsibility or

liability for any errors or inaccuracies that may appear in the document. Rev A | 04/16

Spirent TestCenterPCEP AppNote

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Application Note

Troubleshooting

1� If OSPFv2 router cannot get to Full status, try to change the priority of OSPF router

from 0 to other priority and retry�

2� If the steam cannot be resolved, check the LSDB on DUT� All the LSAs generated

by 1�1�1�10, 1�1�1�11 and 1�1�1�12 should exist in LSDB�

3� If the label of the stream is not 1013 or other unexpected labels, check the base/

range SID on DUT�

Acronyms

DUT Device under Testing

MPLS Multiple Protocol Label Switching

PHP Penultimate Hop Popping