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   Network Working Group
   INTERNET-DRAFT
   Expires in: April 2004
                                                Scott Poretsky
                                                Quarry Technologies

                                                                Brent Imhoff
                                                                Wiltel Communications

                                                October 2003

                Benchmarking Methodology for
                    IGP Data Plane Route Convergence

        <draft-ietf-bmwg-igp-dataplane-conv-meth-01.txt>


   Status of this Memo

   This document is an Internet-Draft and is in full conformance with
   all provisions of Section 10 of RFC2026.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force  (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

   Internet-Drafts are draft documents valid for a maximum of six
   months and may be updated, replaced, or obsoleted by other
   documents at any time.  It is inappropriate to use Internet-Drafts
   as reference material or to cite them other than as "work in
   progress."

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html.


   Table of Contents
     1. Introduction ...............................................2
     2. Existing definitions .......................................2
     3. Test Setup..................................................2
     3.1 Test Topologies............................................2
     3.2 Test Considerations........................................4
     3.2.1 IGP Selection............................................4
     3.2.2 BGP Configuration........................................4
     3.2.3 IGP Route Scaling........................................5
     3.2.4 Timers...................................................5
     3.2.5 Convergence Time Metrics.................................5
     3.2.6 Packet Sampling Interval.................................6
     3.2.7 Interface Type...........................................6
     3.3 Reporting Format...........................................6

Poretsky, Imhoff                                                                [Page 1]


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     4. Test Cases..................................................7
     4.1 Convergence Due to Link Failure............................7
     4.1.1 Convergence Due to Local Interface Failure...............7
     4.1.2 Convergence Due to Neighbor Interface Failure............8
     4.1.3 Convergence Due to Remote Interface Failure..............8
     4.2 Convergence Due to PPP Session Failure.....................9
     4.3 Convergence Due to IGP Adjacency Failure...................10
     4.4 Convergence Due to Route Withdrawal........................10
     4.5 Convergence Due to Cost Change.............................11
     4.6 Convergence Due to ECMP Member Interface Failure...........11
     4.7 Convergence Due to Parallel Link Interface Failure.........12
     5. Security Considerations.....................................13
     6. References..................................................13
     7. Author's Address............................................13
     8. Full Copyright Statement....................................13

   1. Introduction
   This draft describes the methodology for benchmarking IGP Route
   Convergence.  The applicability of this testing is described in
   [1] and the new terminology that it introduces is defined in [2].
   Service Providers use IGP Convergence time as a key metric of
   router design and architecture.  Customers of Service Providers
   observe convergence time by packet loss, so IGP Route Convergence
   is considered a Direct Measure of Quality (DMOQ).  The test cases
   in this document are black-box tests that emulate the network
   events that cause route convergence, as described in [1].  The
   black-box test designs benchmark the data plane accounting for
   all of the factors contributing to route convergence time, as
   discussed in [1].  The methodology (and terminology) for
   benchmarking route convergence can be applied to any link-state
   IGP such as ISIS [3] and OSPF [4].

   2.  Existing definitions

   For the sake of clarity and continuity this RFC adopts the template
   for definitions set out in Section 2 of RFC 1242.  Definitions are
   indexed and grouped together in sections for ease of reference.

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED",  "MAY", and "OPTIONAL" in
   this document are to be interpreted as described in RFC 2119.

   3.  Test Setup
   3.1 Test Topologies

   Figure 1 shows the test topology to measure IGP Route Convergence due
   to local Convergence Events such as SONET Link Failure, PPP Session
   Failure, IGP  Adjacency Failure, Route Withdrawal, and route cost
   change.  These test cases discussed in section 4 provide route
   convergence times that account for the Event Detection time, SPF

Poretsky, Imhoff                                                                [Page 2]


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   Processing time, and FIB Update time.  These times are measured
   by observing packet loss in the data plane.


        ---------       Ingress Interface                   ---------
        |       |<------------------------------|               |
        |         |                                         |           |
        |         | Preferred Egress Interface    |             |
        |  DUT  |------------------------------>|Tester |
        |         |                                         |           |
        |       |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~>|               |
        |         | Next-Best Egress Interface    |             |
        ---------                                           ---------

        Figure 1.  IGP Route Convergence Test Topology for Local Changes

   Figure 2 shows the test topology to measure IGP Route Convergence
   time due to remote changes in the network topology.  These times are
   measured by observing packet loss in the data plane.  In this
   topology the three routers are considered a System Under Test (SUT).


                  -----                         -----------
                  |   | Preferred       |         |
        -----     |R2 |---------------------->|     |
        |   |-->|   | Egress Interface          |           |
        |   |     -----                         |           |
        |R1 |                                           |  Tester |
        |   |     -----                         |           |
        |   |-->|   |   Next-Best       |           |
        -----     |R3 |~~~~~~~~~~~~~~~~~~~~~~>|     |
          ^       |   | Egress Interface  |         |
          |       -----                         -----------
          |                                             |
          |--------------------------------------
                Ingress Interface

        Figure 2.  IGP Route Convergence Test Topology
                        for Remote Changes

   Figure 3 shows the test topology to measure IGP Route Convergence
   time with members of an ECMP Set.  These times are measured by
   observing packet loss in the data plane.  In this topology, the DUT
   is configured with each Egress interface as a member of an ECMP set
   and the Tester emulates multiple next-hop routers (emulates one
   router for each member).







Poretsky, Imhoff                                                                [Page 3]


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        ---------               Ingress Interface               ---------
        |       |<--------------------------------|       |
        |         |                                             |         |
        |         |     ECMP Set Interface 1            |         |
        |  DUT  |-------------------------------->| Tester|
        |         |             .                               |         |
        |         |             .                               |         |
        |         |             .                               |         |
        |       |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~>|       |
        |         |     ECMP Set Interface N            |         |
        ---------                                               ---------

        Figure 3.  IGP Route Convergence Test Topology
                        for ECMP Convergence

   Figure 4 shows the test topology to measure IGP Route Convergence
   time with members of a Parallel Link.  These times are measured by
   observing packet loss in the data plane.  In this topology, the DUT
   is configured with each Egress interface as a member of a Parallel
   Link and the Tester emulates the single next-hop router.

        ---------               Ingress Interface               ---------
        |       |<--------------------------------|       |
        |         |                                             |         |
        |         |     Parallel Link Interface 1       |         |
        |  DUT  |-------------------------------->| Tester|
        |         |             .                               |         |
        |         |             .                               |         |
        |         |             .                               |         |
        |       |~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~>|       |
        |         |     Parallel Link Interface N       |         |
        ---------                                               ---------

        Figure 4.  IGP Route Convergence Test Topology
                      for Parallel Link Convergence

   3.2 Test Considerations

   3.2.1 IGP Selection
   The test cases described in section 4 can be used for ISIS or
   OSPF.  The Route Convergence test methodology for both is
   identical.  The IGP adjacencies are established on the Preferred
   Egress Interface and Next-Best Egress Interface.

   3.2.2 BGP Configuration
   The obtained results for IGP Route Convergence may vary if
   BGP routes are installed.  It is recommended that the IGP
   Convergence times be benchmarked without BGP routes installed.




Poretsky, Imhoff                                                                [Page 4]


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   3.2.3 IGP Route Scaling
   The number of IGP routes will impact the measured IGP Route
   Convergence because convergence for the entire IGP route table is
   measured.   For results similar to those that would be observed in
   an operational network it is recommended that the number of
   installed routes closely approximate that for routers in the
   network.

   3.2.4 Timers
   There are some timers that will impact the measured IGP Convergence
   time. The following timers should be configured to the minimum value
   prior to beginning execution of the test cases:

        Timer                                           Recommended Value
        -----                                           -----------------
        SONET Failure Indication Delay  <10milliseconds
        IGP Hello Timer                         1 second
        IGP Dead-Interval                               3 seconds
        LSA Generation Delay                    0
        LSA Flood Packet Pacing                 0
        LSA Retransmission Packet Pacing        0
        SPF Delay                                       0

   3.2.5 Convergence Time Metrics
   Figure 5 shows a graph model of Convergence Time as measured
   from the data plane.  Refer to [2] for definitions of the terms
   used. Rate-Derived Convergence Time and Loss-Derived Convergence
   Time are the two metrics for convergence time. An offered Load of
   maximum forwarding rate at a fixed packet size is recommended for
   accurate measurement.  The test duration must be greater than the
   convergence time.

   Ideally, Convergence Event Transition and Convergence Recovery
   Transition are instantaneous so that the
   Rate-Derived Convergence Time = Loss-Derived Convergence Time.

   When the Convergence Event Transition and Convergence Recovery
   Transition are not instantaneous so that there is a slope, as
   shown in Figure 5, the accuracy of the Rate-Derived Convergence
   Time and Loss-Derived Convergence Time are dependent upon the
   Packet Sampling Interval.

   Under this condition and the Packet Sampling Interval <= 100
   millisecond, the Rate-Derived Convergence Time > Loss-Derived
   Convergence Time and Rate-Derived Convergence Time is the preferred
   metric.  Under this condition and the Packet Sampling Interval > 100
   millisecond the Rate-Derived Convergence Time < Loss-Derived
   Convergence Time and Loss-Derived Convergence Time is the better
   metric.  For all test cases, the Rate-Derived Convergence Time
   and Loss-Derived Convergence Time must be recorded.



Poretsky, Imhoff                                                                [Page 5]


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                            Recovery  Convergence Event   Time = 0sec
        Maximum              ^           ^                  ^
        Forwarding Rate--> ----\    Packet   /---------------
                                        \    Loss   /<----Convergence
              Convergence------->\           /            Event Transition
        Recovery Transition       \         /
                                           \_____/<------100% Packet Loss

        X-axis = Time
        Y-axis = Forwarding Rate

                        Figure 5. Convergence Graph

   3.2.6 Packet Sampling Interval
   Selection of the Packet Sampling Interval on the Test Equipment
   impacts the measured Rate-Derived Convergence Time.  Packet
   Sampling Interval time is that is too large exaggerates the
   slope of the Convergence Event Transition and Convergence
   Recovery Transition producing a larger than the actual Rate-Derived
   Convergence Time.  This impact is greater as routers achieve
   millisecond convergence times.  The recommended value for the
   Packet Sampling Interval is 100 millisecond.  It is possible to
   have commercially available test equipment with a minimum
   configurable Packet Sampling Interval of 1 second.

   3.2.7 Interface Types
   All test cases in this methodology document may be executed with
   any interface type.  SONET is recommended and specifically
   mentioned in the procedures because it can be configured to have
   no or negligible affect on the measured convergence time.
   Ethernet (10Mb, 100Mb, 1Gb, and 10Gb) is not preferred since
   broadcast media are unable to detect loss of host and rely upon
   IGP Hellos to detect session loss.

   3.3 Reporting Format
   For each test case, it is recommended that the following reporting
   format be completed:














Poretsky, Imhoff                                                                [Page 6]


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        Parameter                                               Units
        ---------                                               -----
        IGP                                                     (ISIS or OSPF)
        Interface Type                                  (GigE, POS, ATM, etc.)
        Packet Size                                             bytes
        IGP Routes                                              number of IGP routes
        Packet Sampling Interval                        seconds or milliseconds
        IGP Timer Values
                SONET Failure Indication Delay  seconds or milliseconds
                IGP Hello Timer                         seconds or milliseconds
                IGP Dead-Interval                               seconds or milliseconds
                LSA Generation Delay                    seconds or milliseconds
                LSA Flood Packet Pacing                 seconds or milliseconds
                LSA Retransmission Packet Pacing        seconds or milliseconds
                SPF Delay                                       seconds or milliseconds
      Results
                Rate-Derived Convergence Time           seconds or milliseconds
                Loss-Derived Convergence Time           seconds or milliseconds
                Restoration Convergence Time            seconds or milliseconds

   4. Test Cases
   4.1 Convergence Due to Link Failure
   4.1.1 Convergence Due to Local Interface Failure
        Objective
        To obtain the IGP Route Convergence due to a local link
        failure event at the DUT's Local Interface.

        Procedure
        1. Advertise matching IGP routes from Tester to DUT on
         Preferred Egress Interface [2] and Next-Best Egress Interface
           [2] using the topology shown in Figure 1.  Set the cost of the
           routes so that the Preferred Egress Interface is the preferred
   next-hop.
        2. Send traffic at maximum forwarding rate to destinations
         matching all IGP routes from Tester to DUT on Ingress Interface
           [2].
        3. Verify traffic routed over Preferred Egress Interface.
        4. Remove SONET on DUT's Local Interface [2] by performing an
           administrative shutdown of the interface.
        5. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as DUT detects the link down event and
           converges all IGP routes and traffic over the Next-Best Egress
           Interface.
        6. Restore SONET on DUT's Local Interface by administratively
           enabling the interface.
        7. Measure Restoration Convergence Time [2] as DUT detects the link
           up event and converges all IGP routes and traffic back to the
           Preferred Egress Interface.

        Results
        The measured IGP Convergence time is influenced by the Local
        SONET indication, SPF delay, SPF Holdtime, SPF Execution
        Time, Tree Build Time, and Hardware Update Time.
Poretsky, Imhoff                                                                [Page 7]


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   4.1.2 Convergence Due to Neighbor Interface Failure
        Objective
        To obtain the IGP Route Convergence due to a local link
        failure event at the Tester's Neighbor Interface.

        Procedure
        1. Advertise matching IGP routes from Tester to DUT on
         Preferred Egress Interface [2] and Next-Best Egress Interface
           [2] using the topology shown in Figure 1.  Set the cost of
           the routes so that the Preferred Egress Interface is the
   preferred next-hop.
        2. Send traffic at maximum forwarding rate to destinations
         matching all IGP routes from Tester to DUT on Ingress
           Interface [2].
        3. Verify traffic routed over Preferred Egress Interface.
        4. Remove SONET on Tester's Neighbor Interface [2] connected to
           DUT' s Preferred Egress Interface.
        5. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as DUT detects the link down event and
           converges all IGP routes and traffic over the Next-Best
           Egress Interface.
        6. Restore SONET on Tester's Neighbor Interface connected to
           DUT's Preferred Egress Interface.
        7. Measure Restoration Convergence Time [2] as DUT detects the
           link up event and converges all IGP routes and traffic back to
           the Preferred Egress Interface.

        Results
        The measured IGP Convergence time is influenced by the Local
        SONET indication, SPF delay, SPF Holdtime, SPF Execution
        Time, Tree Build Time, and Hardware Update Time.

   4.1.3 Convergence Due to Remote Interface Failure

      Objective
        To obtain the IGP Route Convergence due to a Remote
        Interface failure event.

        Procedure
        1. Advertise matching IGP routes from Tester to SUT on
         Preferred Egress Interface [2] and Next-Best Egress Interface
           [2] using the topology shown in Figure 2.  Set the cost of the
           routes so that the Preferred Egress Interface is the preferred
   next-hop.  NOTE: All routers in the SUT must be the same model
   and identically configured.
        2. Send traffic at maximum forwarding rate to destinations
         matching all IGP routes from Tester to DUT on Ingress Interface
           [2].
        3. Verify traffic is routed over Preferred Egress Interface.
        4. Remove SONET on Tester's Neighbor Interface [2] connected to
           SUT' s Preferred Egress Interface.

Poretsky, Imhoff                                                                [Page 8]


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        5. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as SUT detects the link down event and
           converges all IGP routes and traffic over the Next-Best
           Egress Interface.
        6. Restore SONET on Tester's Neighbor Interface connected to
           SUT's Preferred Egress Interface.
        7. Measure Restoration Convergence Time [2] as SUT detects the
           link up event and converges all IGP routes and traffic over
           the Preferred Egress Interface.

        Results
        The measured IGP Convergence time is influenced by the
        SONET failure indication, LSA/LSP Flood Packet Pacing,
        LSA/LSP Retransmission Packet Pacing, LSA/LSP Generation
        time, SPF delay, SPF Holdtime, SPF Execution Time, Tree
        Build Time, and Hardware Update Time.  The additional
        convergence time contributed by LSP Propagation can be
        obtained by subtracting the Rate-Derived Convergence Time
        measured in 4.1.2 (Convergence Due to Neighbor Interface
        Failure) from the Rate-Derived Convergence Time measured in
        this test case.

   4.2 Convergence Due to PPP Session Failure
        Objective
        To obtain the IGP Route Convergence due to a Local PPP Session
        failure event.

        Procedure
        1. Advertise matching IGP routes from Tester to DUT on
           Preferred Egress Interface [2] and Next-Best Egress Interface
           [2] using the topology shown in Figure 1.  Set the cost of
           the routes so that the IGP routes along the Preferred Egress
           Interface is the preferred next-hop.
        2. Send traffic at maximum forwarding rate to destinations
           matching all IGP routes from Tester to DUT on Ingress
           Interface [2].
        3. Verify traffic routed over Preferred Egress Interface.
        4. Remove PPP session from Tester's Neighbor Interface [2]
           connected to Preferred Egress Interface.
        5. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as DUT detects the PPP session down event
           and converges all IGP routes and traffic over the Next-Best
           Egress Interface.
        6. Restore PPP session on DUT's Preferred Egress Interface.
        7. Measure Restoration Convergence Time [2] as DUT detects the
           session up event and converges all IGP routes and traffic over
           the Preferred Egress Interface.

        Results
        The measured IGP Convergence time is influenced by the PPP
      failure indication, SPF delay, SPF Holdtime, SPF Execution
      Time, Tree Build Time, and Hardware Update Time.

Poretsky, Imhoff                                                                [Page 9]


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   4.3 Convergence Due to IGP Adjacency Failure

        Objective
        To obtain the IGP Route Convergence due to a Local IGP Adjacency
        failure event.

        Procedure
        1. Advertise matching IGP routes from Tester to DUT on
         Preferred Egress Interface [2] and Next-Best Egress Interface
           [2] using the topology shown in Figure 1.  Set the cost of
           the routes so that the Preferred Egress Interface is the
           preferred next-hop.
        2. Send traffic at maximum forwarding rate to destinations
           matching all IGP routes from Tester to DUT on Ingress
           Interface [2].
        3. Verify traffic routed over Preferred Egress Interface.
        4. Remove IGP adjacency from Tester's Neighbor Interface [2]
           connected to Preferred Egress Interface.
        5. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as DUT detects the IGP session failure
           event and converges all IGP routes and traffic over the
           Next-Best Egress Interface.
        6. Restore IGP session on DUT's Preferred Egress Interface.
        7. Measure Restoration Convergence Time [2] as DUT detects the
           session up event and converges all IGP routes and traffic over
           the Preferred Egress Interface.

        Results
        The measured IGP Convergence time is influenced by the IGP
        Hello Interval, IGP Dead Interval, SPF delay, SPF Holdtime,
        SPF Execution Time, Tree Build Time, and Hardware Update
        Time.

  4.4 Convergence Due to Route Withdrawal

        Objective
        To obtain the IGP Route Convergence due to Route Withdrawal.

        Procedure
        1. Advertise matching IGP routes from Tester to DUT on
         Preferred Egress Interface [2] and Next-Best Egress Interface
           [2] using the topology shown in Figure 1.  Set the cost of
           the routes so that the Preferred Egress Interface is the
           preferred next-hop.
        2. Send traffic at maximum forwarding rate to destinations
           matching all IGP routes from Tester to DUT on Ingress
           Interface [2].
        3. Verify traffic routed over Preferred Egress Interface.
        4. Tester withdraws all IGP routes from DUT's Local Interface
           on Preferred Egress Interface.


Poretsky, Imhoff                                                                [Page 10]


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        5. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as DUT processes the route withdrawal
           event and converges all IGP routes and traffic over the
           Next-Best Egress Interface.
        6. Re-advertise IGP routes to DUT's Preferred Egress Interface.
        7. Measure Restoration Convergence Time [2] as DUT converges all
           IGP routes and traffic over the Preferred Egress Interface.

        Results
        The measured IGP Convergence time is the SPF Processing and FIB
        Update time as influenced by the SPF delay, SPF Holdtime,
        SPF Execution Time, Tree Build Time, and Hardware Update Time.

   4.5 Convergence Due to Cost Change

        Objective
        To obtain the IGP Route Convergence due to route cost change.

        Procedure
        1. Advertise matching IGP routes from Tester to DUT on
         Preferred Egress Interface [2] and Next-Best Egress Interface
           [2] using the topology shown in Figure 1.  Set the cost of
           the routes so that the Preferred Egress Interface is the
   preferred next-hop.
        2. Send traffic at maximum forwarding rate to destinations
           matching all IGP routes from Tester to DUT on Ingress
           Interface [2].
        3. Verify traffic routed over Preferred Egress Interface.
        4. Tester increases cost for all IGP routes at DUT's Preferred
           Egress Interface so that the Next-Best Egress Inerface
           has lower cost and becomes preferred path.
        5. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as DUT detects the cost change event
           and converges all IGP routes and traffic over the Next-Best
           Egress Interface.
        6. Re-advertise IGP routes to DUT's Preferred Egress Interface
           with original lower cost metric.
        7. Measure Restoration Convergence Time [2] as DUT converges all
           IGP routes and traffic over the Preferred Egress Interface.

        Results
        There should be no measured packet loss for this case.


    4.6 Convergence Due to ECMP Member Interface Failure

        Objective
        To obtain the IGP Route Convergence due to a local link
        failure event of an ECMP Member.


Poretsky, Imhoff                                                                [Page 11]


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        Procedure
        1. Configure ECMP Set as shown in Figure 3.
        2. Advertise matching IGP routes from Tester to DUT on
           each ECMP member.
        3. Send traffic at maximum forwarding rate to destinations
           matching all IGP routes from Tester to DUT on Ingress
           Interface [2].
        4. Verify traffic routed over all members of ECMP Set.
        5. Remove SONET on Tester's Neighbor Interface [2] connected to
           one of the DUT's ECMP member interfaces.
        6. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as DUT detects the link down event and
           converges all IGP routes and traffic over the other ECMP
           members.
        7. Restore SONET on Tester's Neighbor Interface connected to
           DUT's ECMP member interface.
        8. Measure Restoration Convergence Time [2] as DUT detects the
           link up event and converges IGP routes and some distribution
           of traffic over the restored ECMP member.

        Results
        The measured IGP Convergence time is influenced by the Local
        SONET indication, Tree Build Time, and Hardware Update Time.

   4.7 Convergence Due to Parallel Link Interface Failure
        Objective
        To obtain the IGP Route Convergence due to a local link
        failure event for a Member of a Parallel Link.

        Procedure
        1. Configure Parallel Link as shown in Figure 4.
        2. Advertise matching IGP routes from Tester to DUT on
         each Parallel Link member.
        3. Send traffic at maximum forwarding rate to destinations
         matching all IGP routes from Tester to DUT on Ingress
           Interface [2].
        4. Verify traffic routed over all members of Parallel Link.
        5. Remove SONET on Tester's Neighbor Interface [2] connected to
           one of the DUT's Parallel Link member interfaces.
        6. Measure Rate-Derived Convergence Time [2] and Loss-Derived
           Convergence Time [2] as DUT detects the link down event and
           converges all IGP routes and traffic over the other
           Parallel Link members.
        7. Restore SONET on Tester's Neighbor Interface connected to
           DUT's Parallel Link member interface.
        8. Measure Restoration Convergence Time [2] as DUT detects the
           link up event and converges IGP routes and some distribution
           of traffic over the restored Parallel Link member.

        Results
        The measured IGP Convergence time is influenced by the Local
        SONET indication, Tree Build Time, and Hardware Update Time.

Poretsky, Imhoff                                                                [Page 12]


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  5. Security Considerations

        Documents of this type do not directly affect the security of
        the Internet or corporate networks as long as benchmarking
        is not performed on devices or systems connected to operating
        networks.

   6. References

      [1] Poretsky, S., "Benchmarking Applicability for IGP
            Convergence", draft-ietf-bmwg-igp-dataplane-conv-app-01, work
            in progress, October 2003.

        [2] Poretsky, S., Imhoff, B., "Benchmarking Terminology for IGP                     Convergence", draft-ietf-bmwg-igp-dataplane-conv-term-01, work
            in progress, October 2003.

      [3] Callon, R., "Use of OSI IS-IS for Routing in TCP/IP and Dual
            Environments", RFC 1195, December 1990.

      [4] Moy, J., "OSPF Version 2", RFC 2328, IETF, April 1998.

   7. Author's Address

        Scott Poretsky
        Quarry Technologies
        8 New England Executive Park
        Burlington, MA 01803
        USA

        Phone: + 1 781 395 5090
        EMail: sporetsky@quarrytech.com

        Brent Imhoff
        WilTel Communications
        3180 Rider Trail South
        Bridgeton, MO 63045
        USA

        Phone: +1 314 595 6853
        EMail: brent.imhoff@wcg.com


   8.  Full Copyright Statement

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        This document and translations of it may be copied and
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Poretsky, Imhoff                                                                [Page 13]


INTERNET-DRAFT     Benchmarking Methodology for October 2003
                      IGP Data Plane Route Convergence

        prepared, copied, published and distributed, in whole or in
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Poretsky, Imhoff                                                                [Page 14]


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