Network Working Group Rajiv Papneja
Internet Draft Isocore
Intended Status: Informational S.Vapiwala
Expires: April 2, 2009 J. Karthik
Cisco Systems
S. Poretsky
Allot
S. Rao
Qwest Communications
Jean-Louis Le Roux
France Telecom
November 3, 2008
Methodology for Benchmarking MPLS Protection Mechanisms
draft-ietf-bmwg-protection-meth-04.txt
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Abstract
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This draft describes the methodology for benchmarking MPLS
Protection mechanisms for link and node protection as defined in
[MPLS-FRR-EXT]. This document provides test methodologies and test
bed setup for measuring failover times while considering all
dependencies that might impact faster recovery of real-time services
bound to MPLS based traffic engineered tunnels.
The terms used in the procedures included in this document are
defined in [TERM-ID].
Table of Contents
1. Introduction...................................................3
2. Document Scope.................................................4
3. General reference sample topology..............................5
4. Existing definitions...........................................5
5. Test Considerations............................................6
5.1. Failover Events..............................................6
5.2. Failure Detection [TERM-ID]..................................7
5.3. Use of Data Traffic for MPLS Protection benchmarking.........7
5.4. LSP and Route Scaling........................................8
5.5. Selection of IGP.............................................8
5.6. Reversion [TERM-ID]..........................................8
5.7. Traffic Generation...........................................8
5.8. Motivation for Topologies....................................9
6. Reference Test Setup...........................................9
6.1. Link Protection with 1 hop primary (from PLR) and 1 hop backup
TE tunnels.......................................................10
6.2. Link Protection with 1 hop primary (from PLR) and 2 hop backup
TE tunnels.......................................................11
6.3. Link Protection with 2+ hop (from PLR) primary and 1 hop backup
TE tunnels.......................................................11
6.4. Link Protection with 2+ hop (from PLR) primary and 2 hop backup
TE tunnels.......................................................12
6.5. Node Protection with 2 hop primary (from PLR) and 1 hop backup
TE tunnels.......................................................12
6.6. Node Protection with 2 hop primar (from PLR) and 2 hop backup
TE tunnels.......................................................13
6.7. Node Protection with 3+ hop primary (from PLR) and 1 hop backup
TE tunnels.......................................................14
6.8. Node Protection with 3+ hop primary (from PLR) and 2 hop backup
TE tunnels.......................................................15
7. Test Methodology..............................................15
7.1. Headend as PLR with link failure............................15
7.2. Mid-Point as PLR with link failure..........................17
7.3. Headend as PLR with Node Failure............................18
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7.4. Mid-Point as PLR with Node failure..........................19
7.5. MPLS FRR Forwarding Performance Test cases..................21
7.5.1. PLR as Headend............................................21
7.5.2. PLR as Mid-point..........................................22
8. Reporting Format..............................................23
Benchmarks.......................................................24
9. Security Considerations.......................................25
10. IANA Considerations..........................................25
11. References...................................................25
11.1. Normative References.......................................25
11.2. Informative References.....................................25
Author's Addresses...............................................26
Intellectual Property Statement..................................27
Disclaimer of Validity...........................................28
Copyright Statement..............................................28
12. Acknowledgments..............................................28
Appendix A: Fast Reroute Scalability Table.......................28
Appendix B: Abbreviations........................................31
1. Introduction
This draft describes the methodology for benchmarking MPLS based
protection mechanisms. The new terminology that this document
introduces is defined in [TERM-ID].
MPLS based protection mechanisms provide fast recovery of real-time
services from a planned or an unplanned link or node failures. MPLS
protection mechanisms are generally deployed in a network
infrastructure, where MPLS is used for provisioning of point-to-
point traffic engineered tunnels (tunnel). MPLS based protection
mechanisms promises to improve service disruption period by
minimizing recovery time from most common failures.
Generally there two factors impacting service availability - one is
frequency of failures, and other being duration for which the
failures last. Failures can be classified further into two types- -
correlated uncorrelated failures. A Correlated failure is the co-
occurrence of two or more failures simultaneously. A typical example
would be a failure of logical resource (e.g. layer-2 links), relying
on a common physical resource (e.g. common interface) fails. Within
the context of MPLS protection mechanisms, failures that arise due
to Shared Risk Link Groups (SRLG) [MPLS-FRR-EXT] can be considered
as correlations failures or. Not all correlated failures are
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predictable in advance especially the ones caused due to natural
disasters.
Planned failures on the other hand are predictable and
implementations should handle both types of failures and recover
gracefully within the time frame acceptable for service assurance.
Hence, failover recovery time is one of the most important benchmark
that a service provider considers in choosing the building blocks
for their network infrastructure.
It is a known fact that network elements from different manufactures
behave differently to network failures, which impact their ability
to recover from the failures. It becomes imperative from network
service providers to have a common benchmark, which could be
followed to understand the performance behaviors of network
elements.
Considering failover recovery an important parameter, the test
methodology presented in this document considers the factors that
may impact the failover times. To benchmark the failover times, data
plane traffic is used as defined in [IGP-METH].
All benchmarking test cases defined in this document apply to both
facility backup and local protection enabled in detour mode. The
test cases cover all possible failure scenarios and the associated
procedures benchmark the ability of the DUT to perform recovery from
failures within target failover time.
2. Document Scope
This document provides detailed test cases along with different
topologies and scenarios that should be considered to effectively
benchmark MPLS protection mechanisms and failover times. Different
failure scenarios and scaling considerations are also provided in
this document, in addition to reporting formats for the observed
results.
Benchmarking of unexpected correlated failures is currently out of
scope of this document.
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3. General reference sample topology
Figure 1 illustrates the basic reference testbed and is applicable
to all the test cases defined in this document. TG & TA represents
Traffic Generator & Analyzer respectively. A tester is connected to
the DUT and it sends and receives IP traffic along with the working
Path, run protocol emulations simulating real world peering
scenarios. The reference testbed shown in the figure
---------------------------
| ------------|---------------
| | | |
| | | |
-------- -------- -------- -------- --------
TG-| R1 |-----| R2 |----| R3 | | R4 | | R5 |-TA
| |-----| |----| |----| |---| |
-------- -------- -------- -------- --------
| | | |
| | | |
| -------- | |
---------| R6 |-------- |
| |--------------------
--------
Fig.1: Fast Reroute Topology.
The tester MUST record the number of lost, duplicate, and reordered
packets. It should further record arrival and departure times so
that failover Time, Additive Latency, and Reversion Time can be
measured. The tester may be a single device or a test system
emulating all the different roles along a primary or backup path.
4. 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
terms used in this document are defined in detail in [TERM-ID].
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The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in
this document is to be interpreted as described in RFC 2119.
The reader is assumed to be familiar with the commonly used MPLS
terminology, some of which is defined in [MPLS-FRR-EXT].
5. Test Considerations
This section discusses the fundamentals of MPLS Protection testing:
-The types of network events that causes failover
-Indications for failover
-the use of data traffic
-Traffic generation
-LSP Scaling
-Reversion of LSP
-IGP Selection
5.1. Failover Events [TERM ID]
The failover to the backup tunnel is primarily triggered by either
link or node failures observed downstream of the Point of Local
repair (PLR). Some of these failure events are listed below.
Link failure events
- Interface Shutdown on PLR side with POS Alarm
- Interface Shutdown on remote side with POS Alarm
- Interface Shutdown on PLR side with RSVP hello enabled
- Interface Shutdown on remote side with RSVP hello enabled
- Interface Shutdown on PLR side with BFD
- Interface Shutdown on remote side with BFD
- Fiber Pull on the PLR side (Both TX & RX or just the TX)
- Fiber Pull on the remote side (Both TX & RX or just the RX)
- Online insertion and removal (OIR) on PLR side
- OIR on remote side
- Sub-interface failure (e.g. shutting down of a VLAN)
- Parent interface shutdown (an interface bearing multiple sub-
interfaces
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Node failure events
A System reload is initiated either by a graceful shutdown or by a
power failure. A system crash is referred to as a software failure
or an assert.
- Reload protected Node, when RSVP hello is enabled
- Crash Protected Node, when RSVP hello is enabled
- Reload Protected Node, when BFD is enable
- Crash Protected Node, when BFD is enable
5.2. Failure Detection [TERM-ID]
Link failure detection time depends on the link type and failure
detection protocols running. For SONET/SDH, the alarm type (such as
LOS, AIS, or RDI) can be used. Other link types have layer-two
alarms, but they may not provide a short enough failure detection
time. Ethernet based links do not have layer 2 failure indicators,
and therefore relies on layer 3 signaling for failure detection.
MPLS has different failure detection techniques such as BFD, or use
of RSVP hellos. These methods can be used for the layer 3 failure
indicators required by Ethernet based links, or for some other non-
Ethernet based links to help improve failure detection time.
The test procedures in this document can be used for a local failure
or remote failure scenarios for comprehensive benchmarking and to
evaluate failover performance independent of the failure detection
techniques.
5.3. Use of Data Traffic for MPLS Protection benchmarking
Currently end customers use packet loss as a key metric for failover
time. Packet loss is an externally observable event and has direct
impact on customers' applications. MPLS protection mechanism is
expected to minimize the packet loss in the event of a failure. For
this reason it is important to develop a standard router
benchmarking methodology for measuring MPLS protection that uses
packet loss as a metric. At a known rate of forwarding, packet loss
can be measured and the failover time can be determined. Measurement
of control plane signaling to establish backup paths is not enough
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to verify failover. Failover is best determined when packets are
actually traversing the backup path.
An additional benefit of using packet loss for calculation of
failover time is that it allows use of a black-box tests
environment. Data traffic is offered at line-rate to the device
under test (DUT), and an emulated network failure event is forced to
occur, and packet loss is externally measured to calculate the
convergence time. This setup is independent of the DUT architecture.
In addition, this methodology considers the packets in error and
duplicate packets that could have been generated during the failover
process. In scenarios, where separate measurement of packets in
error and duplicate packets is difficult to obtain, these packets
should be attributed to lost packets.
5.4. LSP and Route Scaling
Failover time performance may vary with the number of established
primary and backup tunnel label switched paths (LSP) and installed
routes. However the procedure outlined here should be used for any
number of LSPs (L) and number of routes protected by PLR(R). Number
of L and R must be recorded.
5.5. Selection of IGP
The underlying IGP could be ISIS-TE or OSPF-TE for the methodology
proposed here.
5.6. Reversion [TERM-ID]
Fast Reroute provides a method to return or restore a backup path to
original primary LSP upon recovery from the failure. This is
referred to as Reversion, which can be implemented as Global
Reversion or Local Reversion. In all test cases listed here
Reversion should not produce any packet loss, out of order or
duplicate packets. Each of the test cases in this methodology
document provides a check to confirm that there is no packet loss.
5.7. Traffic Generation
It is suggested that there be one or more traffic streams as long as
there is a steady and constant rate of flow for all the streams. In
order to monitor the DUT performance for recovery times a set of
route prefixes should be advertised before traffic is sent. The
traffic should be configured towards these routes.
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A typical example would be configuring the traffic generator to send
the traffic to the first, middle and last of the advertised routes.
(First, middle and last could be decided by the numerically
smallest, median and the largest respectively of the advertised
prefix). Generating traffic to all of the prefixes reachable by the
protected tunnel (probably in a Round-Robin fashion, where the
traffic is destined to all the prefixes but one prefix at a time in
a cyclic manner) is not recommended. The reason why traffic
generation is not recommended in a Round-Robin fashion to all the
prefixes, one at a time is that if there are many prefixes reachable
through the LSP the time interval between 2 packets destined to one
prefix may be significantly high and may be comparable with the
failover time being measured which does not aid in getting an
accurate failover measurement.
5.8. Motivation for Topologies
Given that the label stack is dependent of the following 3 entities
it is recommended that the benchmarking of failover time be
performed on all the 8 topologies provided in section 4
- Type of protection (Link Vs Node)
- # of remaining hops of the primary tunnel from the PLR
- # of remaining hops of the backup tunnel from the PLR
6. Reference Test Setup
In addition to the general reference topology shown in figure 1,
this section provides detailed insight into various proposed test
setups that should be considered for comprehensively benchmarking
the failover time in different roles along the primary tunnel:
This section proposes a set of topologies that covers all the
scenarios for local protection. All of these 8 topologies shown
(figure 2- figure 9) can be mapped to the reference topology shown
in figure 1. Topologies provided in sections 4.1 to 4.8 refer to
test-bed required to benchmark failover time when DUT is configured
as a PLR in either headend or midpoint role. The labels stack
provided with each topology is at the PLR.
The label stacks shown below each figure in section 4.1 to 4.9
considers enabling of Penultimate Hop Popping (PHP).
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Figures 2-9 uses the following convention:
a) HE is Headend
b) TE is Tail-End
c) MID is Mid point
d) MP is Merge Point
e) PLR is Point of Local Repair
f) PRI is Primary
g) BKP denotes Backup Node
6.1. Link Protection with 1 hop primary (from PLR) and 1 hop backup TE
tunnels
------- -------- PRI --------
| R1 | | R2 | | R3 |
TG-| HE |--| MID |----| TE |-TA
| | | PLR |----| |
------- -------- BKP --------
Figure 2: Represents the setup for section 4.1
Traffic No of Labels No of labels after
before failure failure
IP TRAFFIC (P-P) 0 0
Layer3 VPN (PE-PE) 1 1
Layer3 VPN (PE-P) 2 2
Layer2 VC (PE-PE) 1 1
Layer2 VC (PE-P) 2 2
Mid-point LSPs 0 0
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6.2. Link Protection with 1 hop primary (from PLR) and 2 hop backup TE
tunnels
------- -------- --------
| R1 | | R2 | | R3 |
TG-| HE | | MID |PRI | TE |-TA
| |----| PLR |----| |
------- -------- --------
|BKP |
| -------- |
| | R6 | |
|----| BKP |----|
| MID |
--------
Figure 3: Representing setup for section 4.2
Traffic No of Labels No of labels
before failure after failure
IP TRAFFIC (P-P) 0 1
Layer3 VPN (PE-PE) 1 2
Layer3 VPN (PE-P) 2 3
Layer2 VC (PE-PE) 1 2
Layer2 VC (PE-P) 2 3
Mid-point LSPs 0 1
6.3. Link Protection with 2+ hop (from PLR) primary and 1 hop backup TE
tunnels
-------- -------- -------- --------
| R1 | | R2 |PRI | R3 |PRI | R4 |
TG-| HE |----| MID |----| MID |------| TE |-TA
| | | PLR |----| | | |
-------- -------- BKP -------- --------
Figure 4: Representing setup for section 4.3
Traffic No of Labels No of labels
before failure after failure
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IP TRAFFIC (P-P) 1 1
Layer3 VPN (PE-PE) 2 2
Layer3 VPN (PE-P) 3 3
Layer2 VC (PE-PE) 2 2
Layer2 VC (PE-P) 3 3
Mid-point LSPs 1 1
6.4. Link Protection with 2+ hop (from PLR) primary and 2 hop backup TE
tunnels
-------- -------- PRI -------- PRI --------
| R1 | | R2 | | R3 | | R4 |
TG-| HE |----| MID |----| MID |------| TE |-TA
| | | PLR | | | | |
-------- -------- -------- --------
BKP| |
| -------- |
| | R6 | |
---| BKP |-
| MID |
--------
Figure 5: Representing the setup for section 4.4
Traffic No of Labels No of labels
before failure after failure
IP TRAFFIC (P-P) 1 2
Layer3 VPN (PE-PE) 2 3
Layer3 VPN (PE-P) 3 4
Layer2 VC (PE-PE) 2 3
Layer2 VC (PE-P) 3 4
Mid-point LSPs 1 2
6.5. Node Protection with 2 hop primary (from PLR) and 1 hop backup TE
tunnels
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-------- -------- -------- --------
| R1 | | R2 |PRI | R3 | PRI | R4 |
TG-| HE |----| MID |----| MID |------| TE |-TA
| | | PLR | | | | |
-------- -------- -------- --------
|BKP |
-----------------------------
Figure 6: Representing the setup for section 4.5
Traffic No of Labels No of labels
before failure after failure
IP TRAFFIC (P-P) 1 0
Layer3 VPN (PE-PE) 2 1
Layer3 VPN (PE-P) 3 2
Layer2 VC (PE-PE) 2 1
Layer2 VC (PE-P) 3 2
Mid-point LSPs 1 0
6.6. Node Protection with 2 hop primary (from PLR) and 2 hop backup TE
tunnels
-------- -------- -------- --------
| R1 | | R2 | | R3 | | R4 |
TG-| HE | | MID |PRI | MID |PRI | TE |-TA
| |----| PLR |----| |----| |
-------- -------- -------- --------
| |
BKP| -------- |
| | R6 | |
---------| BKP |---------
| MID |
--------
Figure 7: Representing setup for section 4.6
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Traffic No of Labels No of labels
before failure after failure
IP TRAFFIC (P-P) 1 1
Layer3 VPN (PE-PE) 2 2
Layer3 VPN (PE-P) 3 3
Layer2 VC (PE-PE) 2 2
Layer2 VC (PE-P) 3 3
Mid-point LSPs 1 1
6.7. Node Protection with 3+ hop primary (from PLR) and 1 hop backup TE
tunnels
-------- -------- PRI -------- PRI -------- PRI --------
| R1 | | R2 | | R3 | | R4 | | R5 |
TG-| HE |--| MID |---| MID |---| MP |---| TE |-TA
| | | PLR | | | | | | |
-------- -------- -------- -------- --------
BKP| |
--------------------------
Figure 8: Representing setup for section 4.7
Traffic No of Labels No of labels
before failure after failure
IP TRAFFIC (P-P) 1 1
Layer3 VPN (PE-PE) 2 2
Layer3 VPN (PE-P) 3 3
Layer2 VC (PE-PE) 2 2
Layer2 VC (PE-P) 3 3
Mid-point LSPs 1 1
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6.8. Node Protection with 3+ hop primary (from PLR) and 2 hop backup TE
tunnels
-------- -------- -------- -------- --------
| R1 | | R2 | | R3 | | R4 | | R5 |
TG-| HE | | MID |PRI| MID |PRI| MP |PRI| TE |-TA
| |-- | PLR |---| |---| |---| |
-------- -------- -------- -------- --------
BKP| |
| -------- |
| | R6 | |
---------| BKP |-------
| MID |
--------
Figure 9: Representing setup for section 4.8
Traffic No of Labels No of labels
before failure after failure
IP TRAFFIC (P-P) 1 2
Layer3 VPN (PE-PE) 2 3
Layer3 VPN (PE-P) 3 4
Layer2 VC (PE-PE) 2 3
Layer2 VC (PE-P) 3 4
Mid-point LSPs 1 2
7. Test Methodology
The procedure described in this section can be applied to all the 8
base test cases and the associated topologies. The backup as well as
the primary tunnels are configured to be alike in terms of bandwidth
usage. In order to benchmark failover with all possible label stack
depth applicable as seen with current deployments, it is suggested
that the methodology includes all the scenarios listed here
7.1. Headend as PLR with link failure
Objective
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To benchmark the MPLS failover time due to Link failure events
described in section 3.1 experienced by the DUT which is the point
of local repair (PLR).
Test Setup
- Select any one topology out of 8 from section 4
- Select overlay technology for FRR test e.g. IGP,VPN,or VC
- The DUT will also have 2 interfaces connected to the traffic
Generator/analyzer. (If the node downstream of the PLR is not
A simulated node, then the Ingress of the tunnel should have
one link connected to the traffic generator and the node
downstream to the PLR or the egress of the tunnel should have
a link connected to the traffic analyzer).
Test Configuration
1. Configure the number of primaries on R2 and the backups on R2
as required by the topology selected.
2. Advertise prefixes (as per FRR Scalability table describe
in Appendix A) by the tail end.
Procedure
1. Establish the primary LSP on R2 required by the topology
selected.
2. Establish the backup LSP on R2 required by the selected
topology.
3. Verify primary and backup LSPs are up and that primary is
protected.
4. Verify Fast Reroute protection is enabled and ready.
5. Setup traffic streams as described in section 3.7.
6. Send IP traffic at maximum Forwarding Rate to DUT.
7. Verify traffic switched over Primary LSP.
8. Trigger any choice of Link failure as describe in section 3.1.
9. Verify that primary tunnel and prefixes gets mapped to backup
tunnels.
10. Stop traffic stream and measure the traffic loss.
11. Failover time is calculated as defined in section 6, Reporting
format.
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12. Start traffic stream again to verify reversion when protected
interface comes up. Traffic loss should be 0 due to make
before break or reversion.
13. Enable protected interface that was down (Node in the case of
NNHOP).
14. Verify headend signals new LSP and protection should be in
place again.
7.2. Mid-Point as PLR with link failure
Objective
To benchmark the MPLS failover time due to Link failure events
described in section 3.1 experienced by the device under test which
is the point of local repair (PLR).
Test Setup
- Select any one topology out of 8 from section 4
- Select overlay technology for FRR test as Mid-Point LSPs
- The DUT will also have 2 interfaces connected to the traffic
generator.
Test Configuration
1. Configure the number of primaries on R1 and the backups on R2
as required by the topology selected.
2. Advertise prefixes (as per FRR Scalability table describe in
Appendix A) by the tail end.
Procedure
1. Establish the primary LSP on R1 required by the topology
selected.
2. Establish the backup LSP on R2 required by the selected
topology.
3. Verify primary and backup LSPs are up and that primary is
protected.
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4. Verify Fast Reroute protection.
5. Setup traffic streams as described in section 3.7.
6. Send IP traffic at maximum Forwarding Rate to DUT.
7. Verify traffic switched over Primary LSP.
8. Trigger any choice of Link failure as describe in section 3.1.
9. Verify that primary tunnel and prefixes gets mapped to backup
tunnels.
10. Stop traffic stream and measure the traffic loss.
11. Failover time is calculated as per defined in section 6,
Reporting format.
12. Start traffic stream again to verify reversion when protected
interface comes up. Traffic loss should be 0 due to make
before break or reversion.
13. Enable protected interface that was down (Node in the case of
NNHOP).
14. Verify headend signals new LSP and protection should be in
place again.
7.3. Headend as PLR with Node Failure
Objective
To benchmark the MPLS failover time due to Node failure events
described in section 3.1 experienced by the device under test, which
is the point of local repair (PLR).
Test Setup
- Select any one topology from section 4.5 to 4.8
- Select overlay technology for FRR test e.g. IGP, VPN, or VC
- The DUT will also have 2 interfaces connected to the traffic
generator.
Test Configuration
1. Configure the number of primaries on R2 and the backups on R2
as required by the topology selected.
2. Advertise prefixes (as per FRR Scalability table describe in
Appendix A) by the tail end.
Procedure
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1. Establish the primary LSP on R2 required by the topology
selected.
2. Establish the backup LSP on R2 required by the selected
topology.
3. Verify primary and backup LSPs are up and that primary is
protected.
4. Verify Fast Reroute protection.
5. Setup traffic streams as described in section 3.7.
6. Send IP traffic at maximum Forwarding Rate to DUT.
7. Verify traffic switched over Primary LSP.
8. Trigger any choice of Node failure as describe in section 3.1.
9. Verify that primary tunnel and prefixes gets mapped to backup
tunnels
10. Stop traffic stream and measure the traffic loss.
11. Failover time is calculated as per defined in section 6,
Reporting format.
12. Start traffic stream again to verify reversion when protected
interface comes up. Traffic loss should be 0 due to make
before break or reversion.
13. Boot protected Node that was down.
14. Verify headend signals new LSP and protection should be in
place again.
7.4. Mid-Point as PLR with Node failure
Objective
To benchmark the MPLS failover time due to Node failure events
described in section 3.1 experienced by the device under test, which
is the point of local repair (PLR).
Test Setup
- Select any one topology from section 4.5 to 4.8.
- Select overlay technology for FRR test as Mid-Point LSPs.
- The DUT will also have 2 interfaces connected to the traffic
generator.
Test Configuration
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1. Configure the number of primaries on R1 and the backups on R2
as required by the topology selected.
2. Advertise prefixes (as per FRR Scalability table describe in
Appendix A) by the tail end.
Procedure
1. Establish the primary LSP on R1 required by the topology
selected.
2. Establish the backup LSP on R2 required by the selected
topology.
3. Verify primary and backup LSPs are up and that primary is
protected.
4. Verify Fast Reroute protection.
5. Setup traffic streams as described in section 3.7.
6. Send IP traffic at maximum Forwarding Rate to DUT.
7. Verify traffic switched over Primary LSP.
8. Trigger any choice of Node failure as describe in section 3.1.
9. Verify that primary tunnel and prefixes gets mapped to backup
tunnels.
10. Stop traffic stream and measure the traffic loss.
11. Failover time is calculated as per defined in section 6,
Reporting format.
12. Start traffic stream again to verify reversion when protected
interface comes up. Traffic loss should be 0 due to make
before break or reversion.
13. Boot protected Node that was down.
14. Verify headend signals new LSP and protection should be in
place again.
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7.5. MPLS FRR Forwarding Performance Test cases
For the following MPLS FRR Forwarding Performance Benchmarking
cases, Test the maximum PPS rate allowed by given hardware. One
may follow the procedure for determining MPLS forwarding
performance defined in [MPLS-FORWARD]
7.5.1. PLR as Headend
Objective
To benchmark the maximum rate (pps) on the PLR (as headend) over
primary FRR LSP and backup LSP.
Test Setup
- Select any one topology out of 8 from section 4.
- Select overlay technology for FRR test e.g. IGP,VPN,or VC.
- The DUT will also have 2 interfaces connected to the traffic
Generator/analyzer. (If the node downstream of the PLR is not
A simulated node, then the Ingress of the tunnel should have
one link connected to the traffic generator and the node
downstream to the PLR or the egress of the tunnel should have
a link connected to the traffic analyzer).
Procedure
1. Establish the primary LSP on R2 required by the topology
selected.
2. Establish the backup LSP on R2 required by the selected
topology.
3. Verify primary and backup LSPs are up and that primary is
protected.
4. Verify Fast Reroute protection is enabled and ready.
5. Setup traffic streams as described in section 3.7.
6. Send IP traffic at maximum forwarding rate (pps) that the
device under test supports over the primary LSP.
7. Record maximum PPS rate forwarded over primary LSP.
8. Stop traffic stream.
9. Trigger any choice of Link failure as describe in section 3.1.
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10. Verify that primary tunnel and prefixes gets mapped to backup
tunnels.
11. Send IP traffic at maximum forwarding rate (pps) that the
device under test supports over the primary LSP.
12. Record maximum PPS rate forwarded over backup LSP.
7.5.2. PLR as Mid-point
Objective
To benchmark the maximum rate (pps) on the PLR (as mid-point of the
primary path and ingress of the backup path) over primary FRR LSP
and backup LSP.
Test Setup
- Select any one topology out of 8 from section 4.
- Select overlay technology for FRR test as Mid-Point LSPs.
- The DUT will also have 2 interfaces connected to the traffic
generator.
Procedure
1. Establish the primary LSP on R1 required by the topology
selected.
2. Establish the backup LSP on R2 required by the selected
topology.
3. Verify primary and backup LSPs are up and that primary is
protected.
4. Verify Fast Reroute protection is enabled and ready.
5. Setup traffic streams as described in section 3.7.
6. Send IP traffic at maximum forwarding rate (pps) that the
device under test supports over the primary LSP.
7. Record maximum PPS rate forwarded over primary LSP.
8. Stop traffic stream.
9. Trigger any choice of Link failure as describe in section 3.1.
10. Verify that primary tunnel and prefixes gets mapped to backup
tunnels.
11. Send IP traffic at maximum forwarding rate (pps) that the
device under test supports over the backup LSP.
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12. Record maximum PPS rate forwarded over backup LSP.
8. Reporting Format
For each test, it is recommended that the results be reported in the
following format.
Parameter Units
IGP used for the test ISIS-TE/ OSPF-TE
Interface types Gige,POS,ATM,VLAN etc.
Packet Sizes offered to the DUT Bytes
Forwarding rate Number of packets per
second
IGP routes advertised Number of IGP routes
RSVP hello timers configured Milliseconds
(if any)
Number of FRR tunnels Number of tunnels
configured
Number of VPN routes installed Number of VPN routes
on the headend
Number of VC tunnels Number of VC tunnels
Number of BGP routes BGP routes installed
Number of mid-point tunnels Number of tunnels
Number of Prefixes protected by Number of LSPs
Primary
Topology being used Section number, and
figure reference
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Failure event Event type
Benchmarks
Parameter Unit
Minimum failover time Milliseconds
Mean failover time Milliseconds
Maximum failover time Milliseconds
Minimum reversion time Milliseconds
Mean reversion time Milliseconds
Maximum reversion time Milliseconds
Failover time suggested above is calculated using one of the
following three methods
1. Packet-Based Loss method (PBLM): (Number of packets
dropped/packets per second * 1000) milliseconds. This method
could also be referred as Rate Derived method.
2. Time-Based Loss Method (TBLM): This method relies on the
ability of the Traffic generators to provide statistics which
reveal the duration of failure in milliseconds based on when
the packet loss occurred (interval between non-zero packet loss
and zero loss).
3. Timestamp Based Method (TBM): This method of failover
calculation is based on the timestamp that gets transmitted as
payload in the packets originated by the generator. The Traffic
Analyzer records the timestamp of the last packet received
before the failover event and the first packet after the
failover and derives the time based on the difference between
these 2 timestamps. Note: The payload could also contain
sequence numbers for out-of-order packet calculation and
duplicate packets.
Note: If the primary is configured to be dynamic, and if the primary
is to reroute, make before break should occur from the backup that
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is in use to a new alternate primary. If there is any packet loss
seen, it should be added to failover time.
9. Security Considerations
During the course of test, the test topology must be disconnected
from devices that may forward the test traffic into a production
environment.
There are no specific security considerations within the scope of
this document.
10. IANA Considerations
There are no considerations for IANA at this time.
11. References
11.1. Normative References
[MPLS-FRR-EXT] Pan, P., Atlas, A., Swallow, G., "Fast Reroute
Extensions to RSVP-TE for LSP Tunnels", RFC 4090.
11.2. Informative References
[TERM-ID] Poretsky S., Papneja R., Karthik J., Vapiwala S.,
"Benchmarking Terminology for Protection
Performance", draft-ietf-bmwg-protection-term-
05.txt, work in progress.
[MPLS-FRR-EXT] Pan P., Swallow G., Atlas A., "Fast Reroute
Extensions to RSVP-TE for LSP Tunnels'', RFC 4090.
[IGP-METH] S. Poretsky, B. Imhoff, "Benchmarking Methodology
for IGP Data Plane Route Convergence, draft-ietf-
bmwg-igp-dataplane-conv-meth-16.txt, work in
progress.
[MPLS-FORWARD] A. Akhter, and R. Asati, ''MPLS Forwarding
Benchmarking Methodology,'' draft-ietf-bmwg-mpls-
forwarding-meth-00.txt, work in progress.
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Author's Addresses
Rajiv Papneja
Isocore
12359 Sunrise Valley Drive, STE 100
Reston, VA 20190
USA
Phone: +1 703 860 9273
Email: rpapneja@isocore.com
Samir Vapiwala
Cisco System
300 Beaver Brook Road
Boxborough, MA 01719
USA
Phone: +1 978 936 1484
Email: svapiwal@cisco.com
Jay Karthik
Cisco System
300 Beaver Brook Road
Boxborough, MA 01719
USA
Phone: +1 978 936 0533
Email: jkarthik@cisco.com
Scott Poretsky
Allot Communications
67 South Bedford Street, Suite 400
Burlington, MA 01803
USA
Phone: + 1 508 309 2179
EMail: sporetsky@allot.com
Shankar Rao
Qwest Communications,
950 17th Street
Suite 1900
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Qwest Communications
Denver, CO 80210
USA
Phone: + 1 303 437 6643
Email: shankar.rao@qwest.com
Jean-Louis Le Roux
France Telecom
2 av Pierre Marzin
22300 Lannion
France
Phone: 00 33 2 96 05 30 20
Email: jeanlouis.leroux@orange-ft.com
Intellectual Property Statement
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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
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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 standard. Please address the information to the IETF at
ietf-ipr@ietf.org.
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Disclaimer
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, THE
IETF TRUST 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.
Full Copyright Statement
Copyright (C) The IETF Trust (2008).
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.
12. Acknowledgments
We would like to thank Jean Philip Vasseur for his invaluable input
to the document and Curtis Villamizar his contribution in suggesting
text on definition and need for benchmarking Correlated failures.
Additionally we would like to thank Arun Gandhi, Amrit Hanspal, Karu
Ratnam and for their input to the document.
Appendix A: Fast Reroute Scalability Table
This section provides the recommended numbers for evaluating the
scalability of fast reroute implementations. It also recommends the
typical numbers for IGP/VPNv4 Prefixes, LSP Tunnels and VC entries.
Based on the features supported by the device under test,
appropriate scaling limits can be used for the test bed.
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A 1. FRR IGP Table
No. of Headend TE Tunnels IGP Prefixes
1 100
1 500
1 1000
1 2000
1 5000
2 (Load Balance) 100
2 (Load Balance) 500
2 (Load Balance) 1000
2 (Load Balance) 2000
2 (Load Balance) 5000
100 100
500 500
1000 1000
2000 2000
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A 2. FRR VPN Table
No. of Headend TE Tunnels VPNv4 Prefixes
1 100
1 500
1 1000
1 2000
1 5000
1 10000
1 20000
1 Max
2 (Load Balance) 100
2 (Load Balance) 500
2 (Load Balance) 1000
2 (Load Balance) 2000
2 (Load Balance) 5000
2 (Load Balance) 10000
2 (Load Balance) 20000
2 (Load Balance) Max
A 3. FRR Mid-Point LSP Table
No of Mid-point TE LSPs could be configured at recommended levels -
100, 500, 1000, 2000, or max supported number.
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A 4. FRR VC Table
No. of Headend TE Tunnels VC entries
1 100
1 500
1 1000
1 2000
1 Max
100 100
500 500
1000 1000
2000 2000
Appendix B: Abbreviations
BFD - Bidirectional Fault Detection
BGP - Border Gateway protocol
CE - Customer Edge
DUT - Device Under Test
FRR - Fast Reroute
IGP - Interior Gateway Protocol
IP - Internet Protocol
LSP - Label Switched Path
MP - Merge Point
MPLS - Multi Protocol Label Switching
N-Nhop - Next - Next Hop
Nhop - Next Hop
OIR - Online Insertion and Removal
P - Provider
PE - Provider Edge
PHP - Penultimate Hop Popping
PLR - Point of Local Repair
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RSVP - Resource reSerVation Protocol
SRLG - Shared Risk Link Group
TA - Traffic Analyzer
TE - Traffic Engineering
TG - Traffic Generator
VC - Virtual Circuit
VPN - Virtual Private Network
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