Network Working Group                           
   INTERNET-DRAFT                                  
   Expires in: April 2005                                  
                                                Scott Poretsky
                                                Quarry Technologies


                                                Brent Imhoff
                                                LightCore


                                                October 2004


                        Benchmarking Methodology for 
                      IGP Data Plane Route Convergence


        <draft-ietf-bmwg-igp-dataplane-conv-meth-04.txt>


Intellectual Property Rights (IPR) statement:
By submitting this Internet-Draft, I certify that any applicable
patent or other IPR claims of which I am aware have been disclosed, or
will be disclosed, and any of which I become aware will be disclosed,
in accordance with RFC 3668.


   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.


   ABSTRACT
   This draft describes the methodology for benchmarking IGP Route 
   Convergence as described in Applicability document [1] and 
   Terminology document [2].  The methodology and terminology are 
   to be used for benchmarking route convergence and can be applied 
   to any link-state IGP such as ISIS [3] and OSPF [4].  The terms 
   used in the procedures provided within this document are 
   defined in [2].





Poretsky and Imhoff                                                             [Page 1]


INTERNET-DRAFT    Benchmarking Methodology for  October 2004
                      IGP Data Plane Route Convergence


 Table of Contents
     1. Introduction ...............................................2 
     2. Existing definitions .......................................2
     3. Test Setup..................................................3   
     3.1 Test Topologies............................................3   
     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 Offered Load.............................................5
     3.2.7 Interface Types..........................................5
     3.3 Reporting Format...........................................6
     4. Test Cases..................................................6 
     4.1 Convergence Due to Link Failure............................6
     4.1.1 Convergence Due to Local Interface Failure...............6
     4.1.2 Convergence Due to Neighbor Interface Failure............7
     4.1.3 Convergence Due to Remote Interface Failure..............7
     4.2 Convergence Due to Layer 2 Session Failure.................8
     4.3 Convergence Due to IGP Adjacency Failure...................9
     4.4 Convergence Due to Route Withdrawal........................9
     4.5 Convergence Due to Cost Change.............................10
     4.6 Convergence Due to ECMP Member Interface Failure...........10
     4.7 Convergence Due to Parallel Link Interface Failure.........11 
     5. Security Considerations.....................................12 
     6. References..................................................12
     7. Author's Address............................................12


   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 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


   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.
   Terms related to IGP Convergence are defined in [2].


Poretsky and Imhoff                                                             [Page 2]


INTERNET-DRAFT    Benchmarking Methodology for  October 2004
                      IGP Data Plane Route Convergence


   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, Layer 2 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 
   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).
   NOTE: All routers in the SUT must be the same model and identically configured.     
   
                -----                       -----------
                |   |   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 Equal Cost Multipath (ECMP) Set.  These times are 
   measured by observing packet loss in the data plane.  In this topology, 
   the DUT      


Poretsky and Imhoff                                                             [Page 3]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


   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).


        ---------       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 and Imhoff                                                             [Page 4]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


   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.  The number of areas (for OSPF) and levels (for ISIS) can
   impact the benchmark results.        


   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
   The recommended value for the Packet Sampling Interval [2] is 
   100 milliseconds.  Rate-Derived Convergence Time [2] is the 
   preferred benchmark for IGP Route Convergence.  This benchmark 
   must always be reported when the 
   Packet Sampling Interval [2] <= 100 milliseconds.  
   If the test equipment does not permit the Packet Sampling 
   Interval to be set as low as 100 msec, then both the 
   Rate-Derived Convergence Time and Loss-Derived Convergence 
   Time [2] must be reported.   
   
   3.2.6 Offered Load
   An offered Load of maximum forwarding rate at a fixed packet size 
   is recommended for accurate measurement.  The duration of offered 
   load must be greater than the convergence time.  The destinations 
   for the offered load must be distributed such that all routes are 
   matched.  This enables Full Convergence [2] to be observed.
   
   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.


   
Poretsky and Imhoff                                                             [Page 5]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


   3.3 Reporting Format
   For each test case, it is recommended that the following reporting 
   format be completed:
        
        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
        Benchmarks 
                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] as DUT detects the 
           link down event and converges all IGP routes and traffic over 
           the Next-Best Egress Interface.
        6. Stop offered load.  Wait 30 seconds for queues to drain.  
           Restart Offered Load.
        7. Restore SONET on DUT's Local Interface by administratively
           enabling the interface. 



Poretsky and Imhoff                                                             [Page 6]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


        8. 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.


   4.1.2 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] as DUT detects the 
           link down event and converges all IGP routes and traffic over 
           the Next-Best Egress Interface.
        6. Stop offered load.  Wait 30 seconds for queues to drain.  
           Restart Offered Load.
        7. Restore SONET on Tester's Neighbor Interface connected to 
           DUT's Preferred Egress Interface.
        8. 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.  
Poretsky and Imhoff                                                             [Page 7]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


        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.
        5. Measure Rate-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. Stop offered load.  Wait 30 seconds for queues to drain.  
           Restart Offered Load.
        7. Restore SONET on Tester's Neighbor Interface connected to 
           DUT's Preferred Egress Interface.
        8. 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 
        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 Layer 2 Session Failure
        Objective
        To obtain the IGP Route Convergence due to a Local Layer 2 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 Layer 2 session from Tester's Neighbor Interface [2] 
           connected to Preferred Egress Interface.
        5. Measure Rate-Derived Convergence Time [2] as DUT detects the 
           Layer 2 session down event and converges all IGP routes and 
           traffic over the Next-Best Egress Interface.
        6. Restore Layer 2 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.
Poretsky and Imhoff                                                             [Page 8]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence
        Results
        The measured IGP Convergence time is influenced by the Layer 2 
        failure indication, SPF delay, SPF Holdtime, SPF Execution 
        Time, Tree Build Time, and Hardware Update Time.


   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] as DUT detects the 
           IGP session failure event and converges all IGP routes and 
           traffic over the Next-Best Egress Interface.
        6. Stop offered load.  Wait 30 seconds for queues to drain.  
           Restart Offered Load.
        7. Restore IGP session on DUT's Preferred Egress Interface.
        8. 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].  
Poretsky and Imhoff                                                             [Page 9]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


        3. Verify traffic routed over Preferred Egress Interface.
        4. Tester withdraws all IGP routes from DUT's Local Interface 
           on Preferred Egress Interface.
        6. Stop offered load.  Wait 30 seconds for queues to drain.  
           Restart Offered Load.
        7. Re-advertise IGP routes to DUT's Preferred Egress Interface.
        8. 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 Interface 
           has lower cost and becomes preferred path.
        5. Measure Rate-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. Stop offered load.  Wait 30 seconds for queues to drain.  
           Restart Offered Load.
        7. Re-advertise IGP routes to DUT's Preferred Egress Interface 
           with original lower cost metric.
        8. 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 and Imhoff                                                             [Page 10]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


        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] as DUT detects the 
           link down event and converges all IGP routes and traffic 
           over the other ECMP members.
        7. Stop offered load.  Wait 30 seconds for queues to drain.  
           Restart Offered Load.
        8. Restore SONET on Tester's Neighbor Interface connected to 
           DUT's ECMP member interface.
        9. 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.  The links can be used for
        data Load Balancing


        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] as DUT detects the 
           link down event and converges all IGP routes and traffic over 
           the other Parallel Link members.
        7. Stop offered load.  Wait 30 seconds for queues to drain.  
           Restart Offered Load.
        8. Restore SONET on Tester's Neighbor Interface connected to 
           DUT's Parallel Link member interface.




Poretsky and Imhoff                                                             [Page 11]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


        9. 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.


   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-04, work 
            in progress, October 2004.


      [2] Poretsky, S., Imhoff, B., "Benchmarking Terminology for IGP         
            Convergence", draft-ietf-bmwg-igp-dataplane-conv-term-04, work 
            in progress, October 2004


      [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
        LightCore
        USA
        EMail: bimhoff@planetspork.com







Poretsky and Imhoff                                                             [Page 12]


INTERNET-DRAFT     Benchmarking Methodology for October 2004
                      IGP Data Plane Route Convergence


Intellectual Property Statement


The IETF takes no position regarding the validity or scope of any Intel-
lectual Property Rights or other rights that might be claimed to pertain
to the implementation or use of the technology described in this docu-
ment or the extent to which any license under such rights might or might
not be available; nor does it represent that it has made any independent
effort to identify any such rights.  Information on the procedures with
respect to rights in RFC documents can be found in BCP 78 and BCP 79.


Copies of IPR disclosures made to the IETF Secretariat and any
assurances of licenses to be made available, or the result of an attempt
made to obtain a general license or permission for the use of such
proprietary rights by implementers or users of this specification can be
obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr.


The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary rights
that may cover technology that may be required to implement this stan-
dard.  Please address the information to the IETF at ietf-ipr@ietf.org.


Disclaimer of Warranty


This document and the information contained herein are provided on an
"AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR
IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE INFORMA-
TION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED WARRANTIES OF
MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.


Copyright Statement


Copyright (C) The Internet Society (2004).  This document is subject to
the rights, licenses and restrictions contained in BCP 78, and except as
set forth therein, the authors retain all their rights.















Poretsky and Imhoff                                                             [Page 13]