draft-ietf-bmwg-ospfconv-intraarea-10.txt   rfc4061.txt 
Network Working Group Vishwas Manral
Internet Draft Netplane Systems Network Working Group V. Manral
Russ White Request for Comments: 4061 SiNett Corp.
Category: Informational R. White
Cisco Systems Cisco Systems
Aman Shaikh A. Shaikh
Expiration Date: December 2004 University of California AT&T Labs (Research)
File Name: draft-ietf-bmwg-ospfconv-intraarea-10.txt June 2004 April 2005
Benchmarking Basic OSPF Single Router Control Plane Convergence Benchmarking Basic OSPF Single Router Control Plane Convergence
draft-ietf-bmwg-ospfconv-intraarea-10.txt
Status of this Memo
By submitting this Internet-Draft, I certify that any applicable
patent or other IPR claims of which I am aware have been disclosed,
and any of which I become aware will be disclosed, in accordance with
RFC 3668.
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 Status of This Memo
months. Internet Drafts may be updated, replaced, or obsoleted by
other documents at any time. It is not appropriate to use Internet
Drafts as reference material or to cite them other than as a "working
draft" or "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 This memo provides information for the Internet community. It does
http://www.ietf.org/shadow.html. not specify an Internet standard of any kind. Distribution of this
memo is unlimited.
Copyright Notice Copyright Notice
Copyright (C) The Internet Society (2004). All Rights Reserved. Copyright (C) The Internet Society (2005).
Abstract Abstract
This draft provides suggestions for measuring OSPF single router This document provides suggestions for measuring OSPF single router
control plane convergence. Its initial emphasis is on the control control plane convergence. Its initial emphasis is on the control
plane of single OSPF routers. We do not address forwarding plane plane of a single OSPF router. We do not address forwarding plane
performance. performance.
NOTE: Within this document, the word convergence relates to single NOTE: In this document, the word "convergence" relates to single
router control plane convergence only. router control plane convergence only.
Table of Contents Table of Contents
1. Introduction........................................................1 1. Introduction....................................................2
2. Specification of Requirements.......................................2 2. Specification of Requirements...................................2
3. Overview & Scope....................................................2 3. Overview and Scope..............................................3
4. Reference Topologies................................................3 4. Reference Topologies............................................4
5. Basic Performance Tests.............................................4 5. Basic Performance Tests.........................................5
5.1 Time Required to Process and LSA................................4 5.1. Time Required to Process an LSA...........................5
5.2 Flooding Time...................................................5 5.2. Flooding Time.............................................6
5.3 Shortest Path First Computation Time............................5 5.3. Shortest Path First Computation Time......................6
6. Basic Intra-Area OSPF Tests.........................................7 6. Basic Intra-area OSPF Tests.....................................8
6.1 Forming Adjacencies on Point-to-Point Links (Initialization)....8 6.1. Forming Adjacencies on Point-to-Point Links
6.2 Forming Adjacencies on Point-to-Point Links.....................8 (Initialization)..........................................9
6.3 Forming Adjacencies with Information Already in the Database....9 6.2. Forming Adjacencies on Point-to-Point Links...............9
6.4 Designated Router Election Time on a Broadcast Network.........10 6.3. Forming Adjacencies with Information Already in the
6.5 Initial Convergence Time on a Broadcast Network, Test 1........11 Database.................................................10
6.6 Initial Convergence Time on a Broadcast Network, Test 2........11 6.4. Designated Router Election Time on a Broadcast Network...11
6.7 Link Down with Layer Two Detection.............................12 6.5. Initial Convergence Time on a Broadcast Network,
6.8 Link Down with Layer Three Detection...........................12 Test 1...................................................11
7. IANA Considerations................................................13 6.6. Initial Convergence Time on a Broadcast Network,
8. Security Considerations............................................13 Test 2...................................................12
9. Acknowledgements...................................................13 6.7. Link Down with Layer Two Detection.......................12
10. Normative References..............................................13 6.8. Link Down with Layer Three Detection.....................13
11. Informative References............................................14 7. Security Considerations........................................13
12. Author's Addresses................................................14 8. Acknowledgements...............................................13
13. Full Copyright Statement..........................................15 9. Normative References...........................................14
14. Intellectual Property.............................................15 10. Informative References.........................................14
Authors' Addresses.................................................15
Full Copyright Statement...........................................16
1. Introduction 1. Introduction
There is a growing interest in routing protocol convergence testing, There is a growing interest in routing protocol convergence testing,
with many people looking at various tests to determine how long it with many people looking at various tests to determine how long it
takes for a network to converge after various conditions occur. The takes for a network to converge after various conditions occur. The
major problem with this sort of testing is that the framework of the major problem with this sort of testing is that the framework of the
tests has a major impact on the results; for instance, determining tests has a major impact on the results; for instance, determining
when a network is converged, what parts of the router's operation are when a network is converged, what parts of the router's operation are
considered within the testing, and other such things will have a considered within the testing, and other such things will have a
major impact on what apparent performance routing protocols provide. major impact on the apparent performance that routing protocols
provide.
This document attempts to provide a framework within which Open This document attempts to provide a framework for Open Shortest Path
Shortest Path First [OSPF] performance testing can be placed, and First [OSPF] performance testing, and to provide some tests for
provide some tests with which some aspects of OSPF performance can be measuring some aspects of OSPF performance. The motivation of the
measured. The motivation of the draft is to provide a set of tests document is to provide a set of tests that can provide the user
that can provide the user comparable data from various vendors with comparable data from various vendors with which to evaluate the OSPF
which to evaluate the OSPF protocol performance on the devices. protocol performance on the devices.
2. Specification of Requirements 2. Specification of Requirements
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in [RFC2119]. RFC2119 document are to be interpreted as described in [RFC2119]. RFC2119
keywords in this document are used to assure methodological control, key words in this document are used to ensure methodological control,
which is very important in the specification of benchmarks. This which is very important in the specification of benchmarks. This
document does not specify a network related protocol. document does not specify a network-related protocol.
3. Overview & Scope 3. Overview and Scope
While this document describes a specific set of tests aimed at Although this document describes a specific set of tests aimed at
characterizing the single router control plane convergence characterizing the single router control plane convergence
performance of OSPF processes in routers or other boxes that performance of OSPF processes in routers or other boxes that
incorporate OSPF functionality, a key objective is to propose incorporate OSPF functionality, a key objective is to propose
methodologies that will produce directly comparable convergence methodologies that produce directly comparable convergence-related
related measurements. measurements.
Things which are outside the scope of this document include: The following considerations are outside the scope of this document:
o The interactions of convergence and forwarding; testing is res- o The interactions of convergence and forwarding; testing is
tricted to events occurring within the control plane. Forwarding restricted to events occurring within the control plane.
performance is the primary focus in [INTERCONNECT] and it is Forwarding performance is the primary focus in [INTERCONNECT], and
expected to be dealt with in work that ensues from [FIB-TERM]. it is expected to be dealt with in work that ensues from [FIB-
TERM].
o Inter-area route generation, AS-external route generation, and o Inter-area route generation, AS-external route generation, and
simultaneous traffic on the control and data paths within the simultaneous traffic on the control and data paths within the DUT.
DUT. While the tests outlined in this document measure SPF time, Although the tests outlined in this document measure SPF time,
flooding times, and other aspects of all OSPF convergence per- flooding times, and other aspects of OSPF convergence performance,
formance, it does not provide tests for measuring external or this document does not provide tests for measuring external or
summary route generation, route translation, or other OSPF summary route generation, route translation, or other OSPF inter-
inter-area and external routing performance. These are expected area and external routing performance. These areas are expected
to be dealt with in a later draft. to be dealt with in a later document.
Tests should be run more than once, since a single test run can- The tests should be run more than once, since a single test run
not be relied on to produce statistically sound results. The cannot be relied on to produce statistically sound results. The
number of test runs and any variations between the tests should number of test runs and any variations between the tests should be
be recorded in the test results (see [TERM] for more information recorded in the test results (see [TERM] for more information on
on what items should be recorded in the test results). what items should be recorded in the test results).
4. Reference Topologies 4. Reference Topologies
Several reference topologies will be used throughout the tests Several reference topologies that are used throughout the tests are
described in the remainder of this document. Rather than repeating described in the remaining sections of this document. All of the
these topologies, we've gathered them all in one section. topologies have been collectively placed in one section to avoid
repetition.
o Reference Topology 1 (Emulated Topology) o Reference Topology 1 (Emulated Topology)
( ) ( )
DUT----Generator----( emulated topology ) DUT----Generator----( emulated topology )
( ) ( )
A simple back-to-back configuration. It's assumed that the link A simple back-to-back configuration. It's assumed that the link
between the generator and the DUT is a point-to-point link, between the generator and the DUT is a point-to-point link, while
while the connections within the generator represent some emu- the connections within the generator represent some emulated
lated topology. topology.
o Reference Topology 2 (Generator and Collector) o Reference Topology 2 (Generator and Collector)
( ) ( )
Collector-----DUT-----Generator--( emulated topology ) Collector-----DUT-----Generator--( emulated topology )
\ / ( ) \ / ( )
\------------/ \------------/
All routers are connected through point-to-point links. The cost All routers are connected through point-to-point links. The cost
of all links is assumed to be the same unless otherwise noted. of all links is assumed to be the same unless otherwise noted.
skipping to change at page 4, line 47 skipping to change at page 4, line 48
Any number of routers could be included on the common broadcast Any number of routers could be included on the common broadcast
network. network.
o Reference Topology 4 (Parallel Links) o Reference Topology 4 (Parallel Links)
/--(link 1)-----\ ( ) /--(link 1)-----\ ( )
DUT Generator--( emulated topology ) DUT Generator--( emulated topology )
\--(link 2)-----/ ( ) \--(link 2)-----/ ( )
In all cases the tests and topologies are designed to allow perfor- In all cases the tests and topologies are designed to allow
mance measurements to be taken all on a single device, whether the performance measurements to be taken all on a single device, whether
DUT or some other device in the network. This eliminates the need for this is the DUT or some other device in the network. This eliminates
synchronized clocks within the test networks. the need for synchronized clocks within the test networks.
5. Basic Process Performance Tests 5. Basic Performance Tests
These tests will measure aspects of the OSPF implementation as a pro- These tests will measure aspects of the OSPF implementation as a
cess on the device under test, including: process on the device under test, including
o Time required to process an LSA o time required to process an LSA,
o Flooding time o flooding time, and
o Shortest Path First computation o Shortest Path First computation.
5.1. Time required to process an LSA 5.1. Time Required to Process an LSA
o Using reference topology 1 (Emulated Topology), begin with all o Using reference topology 1 (Emulated Topology), begin with all
links up and a full adjacency established between the DUT and links up and a full adjacency established between the DUT and the
the generator. generator.
Note: The generator does not have direct knowledge of the state Note: The generator does not have direct knowledge of the state of
of the adjacency on the DUT. The fact the adjacency may be in the adjacency on the DUT. The fact that the adjacency may be in
Full on the generator does not mean that the DUT is ready. It Full state on the generator does not mean that the DUT is ready.
may still (and is likely to) be requesting LSAs from the genera- It may still (and is likely to) be requesting LSAs from the
tor. This process, involving processing of requested LSAs, will generator. This process, involving processing of requested LSAs,
affect the results of the test. The generator should either wait will affect the results of the test. The generator should either
until it sees the DUT's router-LSA listing the adjacency with wait until it sees the DUT's router-LSA listing the adjacency with
the generator or introduce a configurable delay before starting the generator or introduce a configurable delay before starting
the test. the test.
o Send an LSA that is already there in the DUT (a duplicate LSA), o Send an LSA that is already in the DUT (a duplicate LSA), note the
note the time difference between when the LSA is sent to when time difference between when the LSA is sent and when the ack is
the ack is received. This measures the time to propagate the LSA received. This measures the time taken to propagate the LSA and
and the ack, as well as processing time of the duplicate LSA. the ack, as well as the processing time of the duplicate LSA.
This is dupLSAprocTime. This is dupLSAprocTime.
o Send a new LSA from the generator to the DUT, followed immedi- o Send a new LSA from the generator to the DUT, followed immediately
ately by a duplicate LSA (LSA that already resides in the data- by a duplicate LSA (LSA that already resides in the database of
base of DUT, but not the same as the one just sent). DUT, but not the same as the one just sent).
o The DUT will acknowledge this second LSA immediately; note the o The DUT will acknowledge this second LSA immediately; note the
time of this acknowledgement. This is newLSAprocTime. time of this acknowledgement. This is newLSAprocTime.
The amount of time required for an OSPF implementation to pro- The amount of time required for an OSPF implementation to process
cess the new LSA can be computed by subtracting dupLSAprocTime the new LSA can be computed by subtracting dupLSAprocTime from
from newLSAprocTime. newLSAprocTime.
Note: The duplicate LSA cannot be the same as the one just sent Note: The duplicate LSA cannot be the same as the one just sent
because of the MinLSInterval restriction.[RFC2328] This test is because of the MinLSInterval restriction [OSPF]. This test is
taken from [BLACKBOX]. taken from [BLACKBOX].
Note: This time may or may not include the time required to per- Note: This time may or may not include the time required to
form flooding-related operations, depending on when the imple- perform flooding-related operations, depending on when the
mentation sends the ack--before it floods the LSA further or implementation sends the ack: before it floods the LSA further, or
after, or anywhere in between. In other words, this measurement after it does, or anywhere in between. In other words, this
may not mean the same thing in all implementations. measurement may not mean the same thing in all implementations.
5.2. Flooding Time 5.2. Flooding Time
o Using reference topology 2 (Generator and Collector), enable o Using reference topology 2 (Generator and Collector), enable OSPF
OSPF on all links and allow the devices to build full adjacen- on all links and allow the devices to build full adjacencies.
cies. Configure the collector so it will block all flooding Configure the collector so that it will block all flooding toward
towards the DUT, although it continues receiving advertisements the DUT (but so that it continues receiving advertisements from
from the DUT. the DUT).
o Inject a new set of LSAs from the generator towards the collec- o Inject a new set of LSAs from the generator toward the collector
tor and the DUT. and the DUT.
o On the collector, note the time the flooding is complete across o On the collector, note the time the flooding is complete across
the link to the generator. Also note the time the flooding is the link to the generator. Also note the time the flooding is
complete across the link from the DUT. complete across the link from the DUT.
The time between the last LSA is received on the collector from the The time from when the last LSA is received on the collector from the
generator and the time the last LSA is received on the collector from generator to when the last LSA is received on the collector from the
the DUT should be measured during this test. This time is important DUT should be measured during this test. This time is important in
in link state protocols, since the loop free nature of the network is link state protocols, since the loop-free nature of the network is
reliant on the speed at which revised topology information is reliant on the speed at which revised topology information is
flooded. flooded.
Depending on the number of LSAs flooded, the sizes of the LSAs, the Depending on the number of LSAs flooded, the sizes of the LSAs, the
number of LSUs, and the rate of flooding, these numbers could vary by number of LSUs, and the rate of flooding, these numbers could vary by
some amount. The settings and variances of these numbers should be some amount. The settings and variances of these numbers should be
reported with the test results. reported with the test results.
5.3. Shortest Path First Computation Time 5.3. Shortest Path First Computation Time
o Use reference topology 1 (Emulated Topology), beginning with the o Use reference topology 1 (Emulated Topology), beginning with the
DUT and the generator fully adjacent. DUT and the generator fully adjacent.
o The default SPF timer on the DUT should be set to 0, so that any o The default SPF timer on the DUT should be set to 0 so that any
new LSA that arrives, immediately results in the SPF calculation new LSA that arrives immediately results in the SPF calculation
[BLACKBOX]. [BLACKBOX].
o The generator should inject a set of LSAs towards the DUT; the o The generator should inject a set of LSAs toward the DUT; the DUT
DUT should be allowed to converge and install all best paths in should be allowed to converge and install all best paths in the
the local routing table, etc.. local routing table, etc.
o Send an LSA that is already there in the DUT (a duplicate LSA), o Send an LSA that is already in the DUT (a duplicate LSA), note the
note the time difference between when the LSA is sent to when time difference between when the LSA is sent and when the ack is
the ack is received. This measures the time to propagate the LSA received. This measures the time taken to propagate the LSA and
and the ack, as well as processing time of the duplicate LSA. the ack, as well as the processing time of the duplicate LSA.
This is dupLSAprocTime. This is dupLSAprocTime.
o Change the link cost between the generator and the emulated net- o Change the link cost between the generator and the emulated
work it is advertising, and transmit the new LSA to the DUT. network it is advertising, and transmit the new LSA to the DUT.
o Immediately inject another LSA which is a duplicate of some o Immediately inject another LSA that is a duplicate of some other
other LSA the generator has previously injected (preferably a LSA the generator has previously injected (preferably a stub
stub network someplace within the emulated network). network someplace within the emulated network).
Note: The generator should make sure that outbound LSA packing Note: The generator should make sure that outbound LSA packing is
is not performed for the duplicate LSAs and they are always sent not performed for the duplicate LSAs and that they are always sent
in a separate Link-state Update packet. Otherwise, if the LSA in a separate Link-state Update packet. Otherwise, if the LSA
carrying the topology change and the duplicate LSA are in the carrying the topology change and the duplicate LSA are in the same
same packet, the SPF will be started the duplicate LSA is acked. packet, the SPF starts after the duplicate LSA is acked.
o Measure the time between transmitting the second (duplicate) LSA o Measure the time between transmitting the second (duplicate) LSA
and the acknowledgement for that LSA; this is the totalSPFtime. and the acknowledgement for that LSA; this is the totalSPFtime.
The total time required to run SPF can be computed by subtract- The total time required to run SPF can be computed by subtracting
ing dupLSAprocTime from totalSPFtime. dupLSAprocTime from totalSPFtime.
The accuracy of this test is crucially dependant on the amount of The accuracy of this test is crucially dependent on the amount of
time between the transmission of the first and second LSAs. If there time between the transmissions of the first and second LSAs. If too
is too much time between them, the test is meaningless because the much time elapsed, the test is meaningless because the SPF run will
SPF run will complete before the second (duplicate) LSA is received. complete before the second (duplicate) LSA is received. If the time
If there is too little time between the LSAs being generated, then elapsed is less, then both LSAs will be handled before the SPF run is
they will both be handled before the SPF run is scheduled and scheduled and started, and thus the measurement would only be for the
started, and thus the measurement would only be for the handling of handling of the duplicate LSA.
the duplicate LSA.
This test is also specified in [BLACKBOX]. This test is also specified in [BLACKBOX].
Note: This test may not be accurate on systems which implement OSPF Note: This test may not be accurate on systems that implement OSPF as
as a multithreaded process, where the flooding takes place in a a multithreaded process, where the flooding takes place in a separate
separate process (or on a different processor) than shortest path process (or on a different processor) than shortest path first
first computations. computations.
It is also possible to measure the SPF time using white box tests It is also possible to measure the SPF time using white box tests
(using output supplied by the OSPF software implementer). For (using output supplied by the OSPF software implementer), such as the
instance: following:
o Using reference topology 1 (Emulated Topology), establish a full o Using reference topology 1 (Emulated Topology), establish a full
adjacency between the generator and the DUT. adjacency between the generator and the DUT.
o Inject a set of LSAs from the generator towards the DUT. Allow o Inject a set of LSAs from the generator toward the DUT. Allow the
the DUT to stabilize and install all best paths in the routing DUT to stabilize and install all best paths in the routing table,
table, etc. etc.
o Change the link cost between the DUT and the generator (or the o Change the link cost between the DUT and the generator (or the
link between the generator and the emulated network it is link between the generator and the emulated network it is
advertising), such that a full SPF is required to run, although advertising), such that a full SPF is required to run, although
only one piece of information is changed. only one piece of information is changed.
o Measure the amount of time required for the DUT to compute new o Measure the amount of time required for the DUT to compute a new
shortest path tree as a result of the topology changes injected shortest path tree as a result of the topology changes injected by
by the generator. These measurements should be taken using the generator. These measurements should be taken using available
available show and debug information on the DUT. show and debug information on the DUT.
Several caveats MUST be mentioned when using a white box method of Several caveats MUST be mentioned when a white box method of
measuring SPF time; for instance, such white box tests are only measuring SPF time is used. For instance, such white box tests are
applicable when testing various versions or variations within a sin- only applicable when testing various versions or variations within a
gle implementation of the OSPF protocol. Further, the same set of single implementation of the OSPF protocol. Further, the same set of
commands MUST be used in each iteration of such a test, to ensure commands MUST be used in each iteration of such a test to ensure
consistent results. consistent results.
There is some interesting relationship between the SPF times reported There is an interesting relationship between the SPF times reported
by white box (internal) testing, and black box (external) testing; by white box (internal) testing and black box (external) testing;
these two types of tests may be used as a "sanity check" on the other each of these two types of tests may be used as a "sanity check" on
type of tests, by comparing the results of the two tests. the other by comparing results.
See [CONSIDERATIONS] for further discussion. See [CONSIDERATIONS] for further discussion.
6. Basic Intra-Area OSPF tests 6. Basic Intra-area OSPF Tests
These tests measure the performance of an OSPF implementation for These tests measure the performance of an OSPF implementation for
basic intra-area tasks, including: basic intra-area tasks, including:
o Forming Adjacencies on Point-to-Point Link (Initialization) o Forming Adjacencies on Point-to-Point Link (Initialization)
o Forming Adjacencies on Point-to-Point Links o Forming Adjacencies on Point-to-Point Links
o Link Up with Information Already in the Database o Link Up with Information Already in the Database
o Initial convergence Time on a Designated Router Electing (Broad- o Initial convergence Time on a Designated Router Electing
cast) Network (Broadcast) Network
o Link Down with Layer 2 Detection o Link Down with Layer 2 Detection
o Link Down with Layer 3 Detection o Link Down with Layer 3 Detection
o Designated Router Election Time on A Broadcast Network o Designated Router Election Time on A Broadcast Network
6.1. Forming Adjacencies on Point-to-Point Link (Initialization) 6.1. Forming Adjacencies on Point-to-Point Link (Initialization)
This test measures the time required to form an OSPF adjacency from This test measures the time required to form an OSPF adjacency from
the time a layer two (data link) connection is formed between two the time a layer two (data link) connection is formed between two
devices running OSPF. devices running OSPF.
skipping to change at page 9, line 18 skipping to change at page 9, line 15
6.1. Forming Adjacencies on Point-to-Point Link (Initialization) 6.1. Forming Adjacencies on Point-to-Point Link (Initialization)
This test measures the time required to form an OSPF adjacency from This test measures the time required to form an OSPF adjacency from
the time a layer two (data link) connection is formed between two the time a layer two (data link) connection is formed between two
devices running OSPF. devices running OSPF.
o Use reference topology 1 (Emulated Topology), beginning with the o Use reference topology 1 (Emulated Topology), beginning with the
link between the generator and DUT disabled on the DUT. OSPF link between the generator and DUT disabled on the DUT. OSPF
should be configured and operating on both devices. should be configured and operating on both devices.
o Inject a set of LSAs from the generator towards the DUT. o Inject a set of LSAs from the generator toward the DUT.
o Bring the link up at the DUT, noting the time that the link car- o Bring the link up at the DUT, noting the time when the link
rier is established on the generator. carrier is established on the generator.
o Note the time the acknowledgement for the last LSA transmitted o Note the time when the acknowledgement for the last LSA
from the DUT is received on the generator. transmitted from the DUT is received on the generator.
The time between the carrier establishment and the acknowledgement The time between the carrier establishment and the acknowledgement
for the last LSA transmitted by the generator should be taken as the for the last LSA transmitted by the generator should be taken as the
total amount of time required for the OSPF process on the DUT to total amount of time required for the OSPF process on the DUT to
react to a link up event with the set of LSAs injected, including the react to a link up event with the set of LSAs injected, including the
time required for the operating system to notify the OSPF process time required for the operating system to notify the OSPF process
about the link up, etc.. The acknowledgement for the last LSA about the link up, etc. The acknowledgement for the last LSA
transmitted is used instead of the last acknowledgement received in transmitted is used instead of the last acknowledgement received in
order to prevent timing skews due to retransmitted acknowledgements order to prevent timing skews due to retransmitted acknowledgements
or LSAs. or LSAs.
6.2. Forming Adjacencies on Point-to-Point Links 6.2. Forming Adjacencies on Point-to-Point Links
This test measures the time required to form an adjacency from the This test measures the time required to form an adjacency from the
time the first communication occurs between two devices running OSPF. time the first communication occurs between two devices running OSPF.
o Using reference topology 1 (Emulated Topology), configure the o Using reference topology 1 (Emulated Topology), configure the DUT
DUT and the generator so traffic can be passed along the link and the generator so that traffic can be passed along the link
between them. between them.
o Configure the generator so OSPF is running on the point-to-point o Configure the generator so that OSPF is running on the point-to-
link towards the DUT, and inject a set of LSAs. point link toward the DUT, and inject a set of LSAs.
o Configure the DUT so OSPF is initialized, but not running on the o Configure the DUT so that OSPF is initialized, but not running on
point-to-point link between the DUT and the generator. the point-to-point link between the DUT and the generator.
o Enable OSPF on the interface between the DUT and the generator o Enable OSPF on the interface between the DUT and the generator on
on the DUT. the DUT.
o Note the time of the first hello received from the DUT on the o Note the time of the first hello received from the DUT on the
generator. generator.
o Note the time of the acknowledgement from the DUT for the last o Note the time of the acknowledgement from the DUT for the last LSA
LSA transmitted on the generator. transmitted on the generator.
The time between the first hello received and the acknowledgement for The time between the first hello received and the acknowledgement for
the last LSA transmitted by the generator should be taken as the the last LSA transmitted by the generator should be taken as the
total amount of time required for the OSPF process on the DUT to total amount of time required for the OSPF process on the DUT to
build a FULL neighbor adjacency with the set of LSAs injected. The build a FULL neighbor adjacency with the set of LSAs injected. The
acknowledgement for the last LSA transmitted is used instead of the acknowledgement for the last LSA transmitted is used instead of the
last acknowledgement received in order to prevent timing skews due to last acknowledgement received in order to prevent timing skews due to
retransmitted acknowledgements or LSAs. retransmitted acknowledgements or LSAs.
6.3. Forming adjacencies with Information Already in the Database 6.3. Forming Adjacencies with Information Already in the Database
o Using reference topology 2 (Generator and Collector), configure o Using reference topology 2 (Generator and Collector), configure
all three devices to run OSPF. all three devices to run OSPF.
o Configure the DUT so the link between the DUT and the generator o Configure the DUT so that the link between the DUT and the
is disabled . generator is disabled.
o Inject a set of LSAs into the network from the generator; the o Inject a set of LSAs into the network from the generator; the DUT
DUT should receive these LSAs through normal flooding from the should receive these LSAs through normal flooding from the
collector. collector.
o Enable the link between the DUT and the generator. o Enable the link between the DUT and the generator.
o Note the time of the first hello received from the DUT on the o Note the time of the first hello received from the DUT on the
generator. generator.
o Note the time of the last DBD received on the generator. o Note the time of the last DBD (Database Description) received on
the generator.
o Note the time of the acknowledgement from the DUT for the last o Note the time of the acknowledgement from the DUT for the last LSA
LSA transmitted on the generator. transmitted on the generator.
The time between the hello received from the DUT by the generator and The time between the hello received by the generator from the DUT and
the acknowledgement for the last LSA transmitted by the generator the acknowledgement for the last LSA transmitted by the generator
should be taken as the total amount of time required for the OSPF should be taken as the total amount of time required for the OSPF
process on the DUT to build a FULL neighbor adjacency with the set of process on the DUT to build a FULL neighbor adjacency with the set of
LSAs injected. In this test, the DUT is already aware of the entire LSAs injected. In this test, the DUT is already aware of the entire
network topology, so the time required should only include the pro- network topology, so the time required should only include the
cessing of DBDs exchanged when in EXCHANGE state, the time to build a processing of DBDs exchanged when in EXCHANGE state, the time to
new router LSA containing the new connection information, and the build a new router LSA containing the new connection information, and
time required to flood and acknowledge this new router LSA. the time required to flood and acknowledge this new router LSA.
The acknowledgement for the last LSA transmitted is used instead of The acknowledgement for the last LSA transmitted is used instead of
the last acknowledgement received in order to prevent timing skews the last acknowledgement received in order to prevent timing skews
due to retransmitted acknowledgements or LSAs. due to retransmitted acknowledgements or LSAs.
6.4. Designated Router Election Time on A Broadcast Network 6.4. Designated Router Election Time on a Broadcast Network
o Using reference topology 3 (Broadcast Network), configure R1 to o Using reference topology 3 (Broadcast Network), configure R1 to be
be the designated router on the link, and the DUT to be the the designated router on the link, and the DUT to be the backup
backup designated router. designated router.
o Enable OSPF on the common broadcast link on all the routers in o Enable OSPF on the common broadcast link on all the routers in the
the test bed. test bed.
o Disable the broadcast link on R1. o Disable the broadcast link on R1.
o Note the time of the last hello received from R1 on R2. o Note the time of the last hello received from R1 on R2.
o Note the time of the first network LSA generated by the DUT as o Note the time of the first network LSA generated by the DUT as
received on R2. received on R2.
The time between the last hello received on R2 and the first network The time between the last hello received on R2 and the first network
LSA generated by the DUT should be taken as the amount of time LSA generated by the DUT should be taken as the amount of time
required for the DUT to complete a designated router election compu- required for the DUT to complete a designated router election
tation. Note this test includes the dead interval timer at the DUT, computation. Note that this test includes the dead interval timer at
so this time may be factored out, or the hello and dead intervals the DUT, so this time may be factored out, or the hello and dead
reduced to make these timers impact the overall test times less. All intervals may be reduced to lessen these timers' impact on the
changed timers, the number of routers connected to the link, and overall test times. All changed timers, the number of routers
other variable factors should be noted in the test results. connected to the link, and other variable factors should be noted in
the test results.
Note: If R1 sends a "goodbye hello," typically a hello with its Note: If R1 sends a "goodbye hello", typically a hello with its
neighbor list empty, in the process of shutting down its interface, neighbor list empty, in the process of shutting down its interface,
using the time this hello is received instead of the time of the last using the time when this hello is received instead of the time when
hello received would provide a more accurate measurement. the last one was would provide a more accurate measurement.
6.5. Initial Convergence Time on a Broadcast Network, Test 1 6.5. Initial Convergence Time on a Broadcast Network, Test 1
o Using reference topology 3 (Broadcast Network), begin with the o Using reference topology 3 (Broadcast Network), begin with the DUT
DUT connected to the network with OSPF enabled. OSPF should be connected to the network with OSPF enabled. OSPF should be
enabled on R1, but the broadcast link should be disabled. enabled on R1, but the broadcast link should be disabled.
o Enable the broadcast link between R1 and the DUT. Note the time o Enable the broadcast link between R1 and the DUT. Note the time
of the first hello received by R1. of the first hello received by R1.
o Note the time the first network LSA is flooded by the DUT at R1. o Note the time when the first network LSA is flooded by the DUT at
R1.
o The differential between the first hello and the first network o The difference between the first hello and the first network LSA
LSA is the time required by the DUT to converge on this new is the time required by the DUT to converge on this new topology.
topology.
This test assumes that the DUT will be the designated router on the This test assumes that the DUT will be the designated router on the
broadcast link. A similar test could be designed to test the conver- broadcast link. A similar test could be designed to test the
gence time when the DUT is not the designated router as well. convergence time when the DUT is not the designated router.
This test may be performed with varying numbers of devices attached This test maybe performed with a varying number of devices attached
to the broadcast network, and varying sets of LSAs being advertised to the broadcast network, and with varying sets of LSAs being
to the DUT from the routers attached to the broadcast network. Varia- advertised to the DUT from the routers attached to the broadcast
tions in the LSA sets and other factors should be noted in the test network. Variations in the LSA sets and other factors should be
results. noted in the test results.
The time required to elect a designated router, as measured in Desig- The time required to elect a designated router, as measured in
nated Router Election Time on A Broadcast Network, above, may be sub- Section 6.4, above, may be subtracted from the results of this test
tracted from the results of this test to provide just the convergence to provide just the convergence time across a broadcast network.
time across a broadcast network.
Note all the other tests in the document include route calculation Note that although all the other tests in this document include route
time in the convergence time, as described in [TERM], this test may calculation time in the convergence time, as described in [TERM],
not include route calculation time in the resulting measured conver- this test may not include route calculation time in the resulting
gence time, because initial route calculation may occur after the measured convergence time, because initial route calculation may
first network LSA is flooded. occur after the first network LSA is flooded.
6.6. Initial Convergence Time on a Broadcast Network, Test 2 6.6. Initial Convergence Time on a Broadcast Network, Test 2
o Using reference topology 3 (Broadcast Network), begin with the o Using reference topology 3 (Broadcast Network), begin with the DUT
DUT connected to the network with OSPF enabled. OSPF should be connected to the network with OSPF enabled. OSPF should be
enabled on R1, but the broadcast link should be disabled. enabled on R1, but the broadcast link should be disabled.
o Enable the broadcast link between R1 and the DUT. Note the time o Enable the broadcast link between R1 and the DUT. Note the time
of the first hello transmitted by the DUT with a designated of the first hello transmitted by the DUT with a designated router
router listed. listed.
o Note the time the first network LSA is flooded by the DUT at R1. o Note the time when the first network LSA is flooded by the DUT at
R1.
o The differential between the first hello with a designated o The time difference between the first hello with a designated
router lists and the first network LSA is the time required by router lists and the first network LSA is the period required by
the DUT to converge on this new topology. the DUT to converge on this new topology.
6.7. Link Down with Layer 2 Detection 6.7. Link Down with Layer 2 Detection
o Using reference topology 4 (Parallel Links), begin with OSPF in o Using reference topology 4 (Parallel Links), begin with OSPF in
the full state between the generator and the DUT. Both links the Full state between the generator and the DUT. Both links
should be point-to-point links with the ability to notify the should be point-to-point links with the ability to notify the
operating system immediately upon link failure. operating system immediately upon link failure.
o Disable link 1; this should be done in such a way that the o Disable link 1; this should be done in such a way that the
keepalive timers at the data link layer will have no impact on keepalive timers at the data link layer will have no impact on the
the DUT recognizing the link failure (the operating system in DUT recognizing the link failure (the operating system in the DUT
the DUT should recognize this link failure immediately). Discon- should recognize this link failure immediately). Disconnecting
necting the cable on the generator end would be one possibility, the cable on the generator end would be one possibility; shutting
or shutting the link down. the link down would be another.
o Note the time of the link failure on the generator. o Note the time of the link failure on the generator.
o At the generator, note the time of the receipt of the new router o At the generator, note the time of the receipt of the new router
LSA from the DUT notifying the generator of the link 2 failure. LSA from the DUT notifying the generator of the link 2 failure.
The difference in the time between the initial link failure and The difference in the time between the initial link failure and
the receipt of the LSA on the generator across link 2 should be the receipt of the LSA on the generator across link 2 should be
taken as the time required for an OSPF implementation to recog- taken as the time required for an OSPF implementation to recognize
nize and process a link failure, including the time required to and process a link failure, including the time required to
generate and flood an LSA describing the link down event to an generate and flood an LSA describing the link down event to an
adjacent neighbor. adjacent neighbor.
6.8. Link Down with Layer 3 Detection 6.8. Link Down with Layer 3 Detection
o Using reference topology 4 (Parallel Links), begin with OSPF in o Using reference topology 4 (Parallel Links), begin with OSPF in
the full state between the generator and the DUT. the Full state between the generator and the DUT.
o Disable OSPF processing on link 1 from the generator. This o Disable OSPF processing on link 1 from the generator. This should
should be done in such a way so it does not affect link status; be done in such a way that it does not affect link status; the DUT
the DUT MUST note the failure of the adjacency through the dead MUST note the failure of the adjacency through the dead interval.
interval.
o At the generator, note the time of the receipt of the new router o At the generator, note the time of the receipt of the new router
LSA from the DUT notifying the generator of the link 2 failure. LSA from the DUT notifying the generator of the link 2 failure.
The difference in the time between the initial link failure and the The difference in the time between the initial link failure and the
receipt of the LSA on the generator across link 2 should be taken as receipt of the LSA on the generator across link 2 should be taken as
the time required for an OSPF implementation to recognize and process the time required for an OSPF implementation to recognize and process
an adjacency failure. an adjacency failure.
7. IANA Considerations 7. Security Considerations
This document requires no IANA considerations.
8. Security Considerations
This document does not modify the underlying security considerations This document does not modify the underlying security considerations
in [OSPF]. in [OSPF].
9. Acknowledgements 8. Acknowledgements
Thanks to Howard Berkowitz, (hcb@clark.net), for his encouragement
and support. Thanks also to Alex Zinin (zinin@psg.net), Gurpreet
Singh (Gurpreet.Singh@SpirentCom.COM), and Yasuhiro Ohara
(yasu@sfc.wide.ad.jp) for their comments as well.
10. Normative References Thanks to Howard Berkowitz (hcb@clark.net) for his encouragement and
support. Thanks also to Alex Zinin (zinin@psg.net), Gurpreet Singh
(Gurpreet.Singh@SpirentCom.com), and Yasuhiro Ohara
(yasu@sfc.wide.ad.jp) for their comments.
[OPSF]Moy, J., "OSPF Version 2", RFC 2328, April 1998. 9. Normative References
[TERM]Manral, V., "OSPF Convergence Testing Terminology and Con- [OSPF] Moy, J., "OSPF Version 2", STD 54, RFC 2328, April
cepts", draft-ietf-bmwg-ospfconv-term-10, June 2004 1998.
[CONSIDERATIONS] [TERM] Manral, V., White, R., and A. Shaikh, "OSPF
Manral, V., "Considerations When Using Basic OSPF Convergence Benchmarking Terminology and Concepts", RFC 4062,
Benchmarks", draft-ietf-bmwg-ospfconv-applicability-07, June April 2005.
2004
[RFC2119] [CONSIDERATIONS] Manral, V., White, R., and A. Shaikh,
Bradner, S., "Key words for use in RFCs to Indicate Requirement "Considerations When Using Basic OSPF Convergence
Levels", BCP 14, RFC 2119, March 1997 Benchmarks", RFC 4063, April 2005.
11. Informative References [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[INTERCONNECT] 10. Informative References
Bradner, S., McQuaid, J., "Benchmarking Methodology for Network
Interconnect Devices", RFC2544, March 1999.
[MILLISEC] [INTERCONNECT] Bradner, S. and J. McQuaid, "Benchmarking
Alaettinoglu C., et al., "Towards Milli-Second IGP Convergence" Methodology for Network Interconnect Devices", RFC
draft-alaettinoglu-isis-convergence 2544, March 1999.
[FIB-TERM] [FIB-TERM] Trotter, G., "Terminology for Forwarding Information
Trotter, G., "Terminology for Forwarding Information Base (FIB) Base (FIB) based Router Performance", RFC 3222,
based Router Performance", RFC3222, October 2001. December 2001.
[BLACKBOX] [BLACKBOX] Shaikh, A. and Greenberg, A., "Experience in Black-
Shaikh, Aman, Greenberg, Albert, "Experience in Black-Box OSPF box OSPF measurement", Proc. ACM SIGCOMM Internet
measurement" Measurement Workshop (IMW), November 2001
12. Authors' Addresses Authors' Addresses
Vishwas Manral Vishwas Manral
Netplane Systems SiNett Corp,
189 Prashasan Nagar Ground Floor,
Road number 72 Embassy Icon Annexe,
Jubilee Hills 2/1, Infantry Road,
Hyderabad, India Bangalore, India
vmanral@netplane.com EMail: vishwas@sinett.com
Russ White Russ White
Cisco Systems, Inc. Cisco Systems, Inc.
7025 Kit Creek Rd. 7025 Kit Creek Rd.
Research Triangle Park, NC 27709 Research Triangle Park, NC 27709
riw@cisco.com EMail: riw@cisco.com
Aman Shaikh Aman Shaikh
AT&T Labs (Research) AT&T Labs (Research)
180, Park Av 180 Park Av, PO Box 971
Florham Park, NJ 07932 Florham Park, NJ 07932
ashaikh@research.att.com EMail: ashaikh@research.att.com
Intellectual Property Statement Full Copyright Statement
The IETF takes no position regarding the validity or scope of any Intel- Copyright (C) The Internet Society (2005).
lectual Property Rights or other rights that might be claimed to pertain
to the implementation or use of the technology described in this docu- This document is subject to the rights, licenses and restrictions
ment or the extent to which any license under such rights might or might contained in BCP 78, and except as set forth therein, the authors
not be available; nor does it represent that it has made any independent retain all their rights.
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. 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
INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
Intellectual Property
The IETF takes no position regarding the validity or scope of any
Intellectual Property Rights or other rights that might be claimed to
pertain to the implementation or use of the technology described in
this document 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 Copies of IPR disclosures made to the IETF Secretariat and any
assurances of licenses to be made available, or the result of an attempt assurances of licenses to be made available, or the result of an
made to obtain a general license or permission for the use of such attempt made to obtain a general license or permission for the use of
proprietary rights by implementers or users of this specification can be such proprietary rights by implementers or users of this
obtained from the IETF on-line IPR repository at specification can be obtained from the IETF on-line IPR repository at
http://www.ietf.org/ipr. http://www.ietf.org/ipr.
The IETF invites any interested party to bring to its attention any The IETF invites any interested party to bring to its attention any
copyrights, patents or patent applications, or other proprietary rights copyrights, patents or patent applications, or other proprietary
that may cover technology that may be required to implement this stan- rights that may cover technology that may be required to implement
dard. Please address the information to the IETF at ietf-ipr@ietf.org. this standard. 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 Acknowledgement
Copyright (C) The Internet Society (2004). This document is subject to Funding for the RFC Editor function is currently provided by the
the rights, licenses and restrictions contained in BCP 78, and except as Internet Society.
set forth therein, the authors retain all their rights.
 End of changes. 

This html diff was produced by rfcdiff 1.25, available from http://www.levkowetz.com/ietf/tools/rfcdiff/