Internet DRAFT - draft-bb-2544like-production-tests
draft-bb-2544like-production-tests
Network Working Group R. Bonica
Internet-Draft Juniper Networks
Intended status: Informational S. Bryant
Expires: April 25, 2013 Cisco Systems
October 22, 2012
RFC2544 Testing in Production Networks
draft-bb-2544like-production-tests-00
Abstract
This document considers the use of RFC2544 type tests in an
production network.
Status of this Memo
This Internet-Draft is submitted in full conformance with the
provisions of BCP 78 and BCP 79.
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material or to cite them other than as "work in progress."
This Internet-Draft will expire on April 25, 2013.
Copyright Notice
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Table of Contents
1. Conventions used in the document . . . . . . . . . . . . . . . 3
2. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3
3. Cautious of RFC2544 in Production Networks . . . . . . . . . . 3
4. Real World . . . . . . . . . . . . . . . . . . . . . . . . . . 3
5. Test To Be Run . . . . . . . . . . . . . . . . . . . . . . . . 4
6. Evaluating the Results . . . . . . . . . . . . . . . . . . . . 4
7. Requirements . . . . . . . . . . . . . . . . . . . . . . . . . 4
8. The Test Set Up . . . . . . . . . . . . . . . . . . . . . . . 5
9. DUT set up . . . . . . . . . . . . . . . . . . . . . . . . . . 5
10. Frame Formats . . . . . . . . . . . . . . . . . . . . . . . . 5
11. Frame Sizes. . . . . . . . . . . . . . . . . . . . . . . . . . 5
12. Verifying received frames . . . . . . . . . . . . . . . . . . 6
13. Modifiers . . . . . . . . . . . . . . . . . . . . . . . . . . 6
14. Protocol Addresses . . . . . . . . . . . . . . . . . . . . . . 9
15. Route Set up . . . . . . . . . . . . . . . . . . . . . . . . . 9
16. Bidirectional traffic . . . . . . . . . . . . . . . . . . . . 9
17. Single Stream Path . . . . . . . . . . . . . . . . . . . . . . 9
18. Multi-port . . . . . . . . . . . . . . . . . . . . . . . . . . 10
19. Multiple Protocols . . . . . . . . . . . . . . . . . . . . . . 10
20. Multiple frame sizes . . . . . . . . . . . . . . . . . . . . . 10
21. Testing performance beyond a single DUT. . . . . . . . . . . . 10
22. Maximum frame rate . . . . . . . . . . . . . . . . . . . . . . 10
23. Bursty Traffic . . . . . . . . . . . . . . . . . . . . . . . . 11
24. Rings . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
25. Trial description . . . . . . . . . . . . . . . . . . . . . . 11
26. Trial duration . . . . . . . . . . . . . . . . . . . . . . . . 11
27. Address resolution . . . . . . . . . . . . . . . . . . . . . . 11
28. Benchmarking tests . . . . . . . . . . . . . . . . . . . . . . 12
28.1. Throughput . . . . . . . . . . . . . . . . . . . . . . . 12
28.2. Latency . . . . . . . . . . . . . . . . . . . . . . . . . 12
28.3. Frame loss rate . . . . . . . . . . . . . . . . . . . . . 12
28.4. Back-to-back frames . . . . . . . . . . . . . . . . . . . 12
28.5. System Recovery . . . . . . . . . . . . . . . . . . . . . 12
28.6. Reset . . . . . . . . . . . . . . . . . . . . . . . . . . 12
29. IANA considerations . . . . . . . . . . . . . . . . . . . . . 13
30. Security considerations . . . . . . . . . . . . . . . . . . . 13
31. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 13
32. Informative References . . . . . . . . . . . . . . . . . . . . 13
Appendix A. Testing Considerations . . . . . . . . . . . . . . . 13
Appendix B. Maximum frame rates refer . . . . . . . . . . . . . . 14
Appendix C. Test Frame Formats . . . . . . . . . . . . . . . . . 15
Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15
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1. Conventions used in the document
The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
"SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
document are to be interpreted as described in RFC2119 [RFC2119].
2. Introduction
This document considers the issues related to conducting tests
similar to RFC2544 [RFC2544] in a prodcution network.
3. Cautious of RFC2544 in Production Networks
Some types of production network offer a high degree of assured
issolation between the traffic of different users. An example of a
network technique that provides this issolation is a pseudowire
[RFC3985]. Some types of network, known as transport networks
[RFC5921] are traffic engineered to the point where there is normally
no resource contention betwen user traffic. The incautous use of
unmodified RFC2544 testing is NOT RECOMMENDED [RFC2544]. However
provided suitable approprate caution is applied the existing RFC2544
tests may provide some useful information on the behaviour of such a
network.
When using unmodified RFC2544 tests on such a network the tester
needs to be aware that the latency and latency variation will be
significantly higher than in a laboratory environment, and that error
rate and hence packet loss may be higher than in a laboratory
environment. It is therefore necessary to repeat tests a number of
times to be confident of the results and to present the outcome in a
statistical rather than definitive form. It is also necessary to
note that the results represent the behaviour of the system and
network at the time of measurement and may not reperesent the
behaviour at some other time in the past or in the future.
Unmodified RFC2544 tests MUST NOT be conducted on a production
network unless the tester is confident that the required degree of
resource issolation is in place such that the tests will not be
harmful to the network itself, other user traffic, or the performance
applications using the network as a data path.
4. Real World
The following text does not seem useful as it is self evident and
thus I propose to delete the section.
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[2. Real world
In producing this document the authors attempted to keep in mind the
requirement that apparatus to perform the described tests must
actually be built. We do not know of "off the shelf" equipment
available to implement all of the tests but it is our opinion that
such equipment can be constructed.]
5. Test To Be Run
The advice in [RFC2544] Section 3 regarding the applicability and
usefulness of the tests applies to the situation considered in this
document
6. Evaluating the Results
As noted in RFC2544 [RFC2544] Section 4 the test will produce a great
deal of data, more so in the case when the tests are conducted on a
production network, since it is advisable to repeat the tests to
ensure that the results are statically representative of the
behaviour of the devices and network path at the time of the test.
In particular behavior such as latency variation or packet loss needs
to be properly characterised. Automation of the instumentation and
improvements in display and visualization since RFC2544 was written
should assist with this.
As noted in RFC2544 the selection of the to be run and evaluation of
the test data must therefore be done with an understanding of
generally accepted testing practices regarding repeatability,
variance, the tatistical significance of small numbers of trials and
the nature of the production network.
7. Requirements
An implementation is not compliant if it fails to satisfy one or more
of the MUST requirements for the protocols it implements. An
implementation that satisfies all the MUST and all the SHOULD
requirements for its protocols is said to be "unconditionally
compliant"; one that satisfies all the MUST requirements but not all
the SHOULD requirements for its protocols is said to be
"conditionally compliant".
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8. The Test Set Up
There are two cases to be considered when setting up a test. The
first case is where the production network is providing an emulated
physical or datalink serice such as a pseudowir, and this service is
the subject of the test. This is similar to the case shown in Figure
2 of [RFC2544] , noting that either the service emulation will need
to be put in loopback, or a second service will need to be provsioned
to return the test traffic to the tester.
The second case concerns where it is desired to determine the
performance of a system that is handing off packets a packet
equipment such as a Router (or a lable switched router (LSR)), such
as when testing a virtual private network (VPN) service. This is
similar to the case shown in Figure 3 of RFC2544.
In both cases it should be noted that measurements taken will be
subject to imparement on both the outward path and the return path,
and that it is not possible to easily determine the degree of
imparement attributable to each path. It will be the case that the
path that is the subject of the test will, other than under
pathalogical conditions, exhibit a performance that is at least as
good as the measurements taken.
9. DUT set up
The advice in section 7 of [RFC2544] applies, with the exception that
protocols and protocol modes not supported by the production network
MUST NOT be configured or tested. The protocol profile tested MUST
be included or referenced in ant test report.
10. Frame Formats
The advice in Section 8 of [RFC2544]regarding Frame Formats applies.
Given the evolution of network technology since 1999, some additional
frame formats will be required, but these are out of scope for this
document.
11. Frame Sizes.
The advice in Section 9 of [RFC2544] regarding frame size should be
followed.
Since the publication of RFC2544 the maximum packet size supported on
Ethernet [anything else???] has increased with the introduction of
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jumbo frames. The set of frame sizes tested SHOULD include the
maxium size supported by the network. The maximum size tested MUST
be included in the test report. This maximum size may be set by
configuration, or may be determined by the tester automatically using
a discovery technique. Such a discovery technique should preferable
be log n efficient such as a binary chop search. The discovered
maximum packet size should be verified a number of times (at least
five times is RECOMMENDED) until a consistant result is achieved.
12. Verifying received frames
The advice in Section 10 of [RFC2544] SHOULD be followed regarding
verification of frames
13. Modifiers
The advice in Section 10 of [RFC2544] SHOULD be followed regarding
verification of frames
[ We might want to update the following, although that really needs
to be aligned with more modern advice on the lab version of this
specification
The rest of section 13 to be deleted
It might be useful to know the DUT performance under a number of
conditions; some of these conditions are noted below. The reported
results SHOULD include as many of these conditions as the test
equipment is able to generate. The suite of tests SHOULD be first
run without any modifying conditions and then repeated under each of
the conditions separately. To preserve the ability to compare the
results of these tests any frames that are required to generate the
modifying conditions (management queries for example) will be
included in the same data stream as the normal test frames in place
of one of the test frames and not be supplied to the DUT on a
separate network port.
11.1 Broadcast frames
In most router designs special processing is required when frames
addressed to the hardware broadcast address are received. In bridges
(or in bridge mode on routers) these broadcast frames must be flooded
to a number of ports. The stream of test frames SHOULD be augmented
with 1% frames addressed to the hardware broadcast address. The
frames sent to the broadcast address should be of a type that the
router will not need to process. The aim of this test is to
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determine if there is any effect on the forwarding rate of the other
data in the stream. The specific frames that should be used are
included in the test frame format document. The broadcast frames
SHOULD be evenly distributed throughout the data stream, for example,
every 100th frame.
The same test SHOULD be performed on bridge-like DUTs but in this
case the broadcast packets will be processed and flooded to all
outputs.
It is understood that a level of broadcast frames of 1% is much
higher than many networks experience but, as in drug toxicity
evaluations, the higher level is required to be able to gage the
effect which would otherwise often fall within the normal variability
of the system performance. Due to design factors some test equipment
will not be able to generate a level of alternate frames this low.
In these cases the percentage SHOULD be as small as the equipment can
provide and that the actual level be described in the report of the
test results.
11.2 Management frames
Most data networks now make use of management protocols such as SNMP.
In many environments there can be a number of management stations
sending queries to the same DUT at the same time.
The stream of test frames SHOULD be augmented with one management
query as the first frame sent each second during the duration of the
trial. The result of the query must fit into one response frame.
The response frame SHOULD be verified by the test equipment. One
example of the specific query frame that should be used is shown in
Appendix C.
11.3 Routing update frames
The processing of dynamic routing protocol updates could have a
significant impact on the ability of a router to forward data frames.
The stream of test frames SHOULD be augmented with one routing update
frame transmitted as the first frame transmitted during the trial.
Routing update frames SHOULD be sent at the rate specified in
Appendix C for the specific routing protocol being used in the test.
Two routing update frames are defined in Appendix C for the TCP/IP
over Ethernet example. The routing frames are designed to change the
routing to a number of networks that are not involved in the
forwarding of the test data. The first frame sets the routing table
state to "A", the second one changes the state to "B". The frames
MUST be alternated during the trial.
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The test SHOULD verify that the routing update was processed by the
DUT.
11.4 Filters
Filters are added to routers and bridges to selectively inhibit the
forwarding of frames that would normally be forwarded. This is
usually done to implement security controls on the data that is
accepted between one area and another. Different products have
different capabilities to implement filters.
The DUT SHOULD be first configured to add one filter condition and
the tests performed. This filter SHOULD permit the forwarding of the
test data stream. In routers this filter SHOULD be of the form:
forward input_protocol_address to output_protocol_address
In bridges the filter SHOULD be of the form:
forward destination_hardware_address
The DUT SHOULD be then reconfigured to implement a total of 25
filters. The first 24 of these filters SHOULD be of the form:
block input_protocol_address to output_protocol_address
The 24 input and output protocol addresses SHOULD not be any that are
represented in the test data stream. The last filter SHOULD permit
the forwarding of the test data stream. By "first" and "last" we
mean to ensure that in the second case, 25 conditions must be checked
before the data frames will match the conditions that permit the
forwarding of the frame. Of course, if the DUT reorders the filters
or does not use a linear scan of the filter rules the effect of the
sequence in which the filters are input is properly lost.
The exact filters configuration command lines used SHOULD be included
with the report of the results.
11.4.1 Filter Addresses
Two sets of filter addresses are required, one for the single filter
case and one for the 25 filter case.
The single filter case should permit traffic from IP address
198.18.1.2 to IP address 198.19.65.2 and deny all other traffic.
The 25 filter case should follow the following sequence.
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deny aa.ba.1.1 to aa.ba.100.1 deny aa.ba.2.2 to aa.ba.101.2 deny
aa.ba.3.3 to aa.ba.103.3 ... deny aa.ba.12.12 to aa.ba.112.12 allow
aa.bc.1.2 to aa.bc.65.1 deny aa.ba.13.13 to aa.ba.113.13 deny
aa.ba.14.14 to aa.ba.114.14 ... deny aa.ba.24.24 to aa.ba.124.24 deny
all else
All previous filter conditions should be cleared from the router
before this sequence is entered. The sequence is selected to test to
see if the router sorts the filter conditions or accepts them in the
order that they were entered. Both of these procedures will result
in a greater impact on performance than will some form of hash
coding.]
14. Protocol Addresses
Where the test traffic is fully issolated from production traffic,
for example when running over a PW, the advice in Section 12 of
[RFC2544] MAY be followed.
Where the test traffic shares the network with the production
traffic, the addresses used MUST be those that are correctly routed
to the designated test traffic receiver. Correct routing of this
traffic at a low data rate MUST be verified prior to running tests
that subject the test receiver to a significant load.
15. Route Set up
Where the test traffic is fully issolated from production traffic,
for example when running over a PW, the advice in Section 12 of
[RFC2544] MAY be followed.
Where the test traffic shares the network with production traffic,
the existing routing protocols SHOULD be used to set up the routed
path between the test traffic source and the test traffic
destination.
16. Bidirectional traffic
The advice on traffic bidirectionality in Section 14 of [RFC2544]
SHOULD be followed.
17. Single Stream Path
The advice on stream selection in Section 15 of [RFC2544] SHOULD be
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followed.
18. Multi-port
The advice on exercising the ability of the DUT to concurrently
receive packets for the same destination port giveb in Section 16 of
[RFC2544] SHOULD be followed.
19. Multiple Protocols
The advice on multiple protocols given in Section 17 of [RFC2544]
SHOULD be followed.
20. Multiple frame sizes
The advice on multiple frame sizes given in Section 18 of [RFC2544]
SHOULD be followed.
21. Testing performance beyond a single DUT.
Section 19 of [RFC2544] discusses testing of multiple systems. This
is the normal case in a production network. As noted in RFC2544 such
tests require care in care in interpretation. Unlike the laboratory
benchmrk case however, the test will be exercising the network in the
expected configuration, and thus is representive of the opertion of
the system with the background traffic load of the time. It is
RECOMMENDED that the test be repeated a number of times to guage the
effect of variation of background traffic over both short and long
term time frames. The times of the test SHOULD be logged, and the
results presented in such a way that the statistical nature of the
test be clear to the reviewer. It should be noted whether the type
of production network was such that it would or not it would be
anticipated that the test would be repeatable within the statistical
significance of the measurements.
22. Maximum frame rate
The advice on maximum frame rate given in Section 20 of RFC2544
[RFC2544] SHOULD be followed.
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23. Bursty Traffic
The advice in Section 21 of [RFC2544] on bursty traffic SHOULD be
followed.
Editor's Note Do we need to recomemnd larger burst sizes?
24. Rings
[This is probably obselete now - suggest we delete the section
Although it is possible to configure some token ring and FDDI
interfaces to transmit more than one frame each time that the token
is received, most of the network devices currently available transmit
only one frame per token. These tests SHOULD first be performed
while transmitting only one frame per token.
Some current high-performance workstation servers do transmit more
than one frame per token on FDDI to maximize throughput. Since this
may be a common feature in future workstations and servers,
interconnect devices with FDDI interfaces SHOULD be tested with 1, 4,
8, and 16 frames per token. The reported frame rate SHOULD be the
average rate of frame transmission over the total trial period.]
25. Trial description
If the prodcution network is providing a layer 1 or layer 2 service,
then the test may be conducted as described in Section 23 of
[RFC2544]. If the production network is providing a layer 3 service
care MUST be taken to ensure that any routes intruduced may be safely
announced by the DUT without causing disruption to production
traffic, and at such a volume that the route processors in the
production network are not overloaded.
26. Trial duration
The advice in Section 24 of [RFC2544] on trial duration is
applicable.
27. Address resolution
As stated in Section 25 of [RFC2544], the DUT SHOULD be able to
respond to address resolution requests sent by the DUT wherever the
protocol requires such a process.
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28. Benchmarking tests
28.1. Throughput
The throughput test described in Section 26.1 of [RFC2544]applies.
However the reporting of a single number is NOT RECOMMENDED. If a
single is reported, it must be measured at a time during the busy
period, and the value of the lower decile SHOULD be reported.
28.2. Latency
The latency testing described in Section 26.1 of [RFC2544] applies.
Measurements SHOULD be carried out during the busy period. The
statistical averaging approach is for further study.
28.3. Frame loss rate
The frame loss proceedure described in Section 26.3 of [RFC2544] is
modified as follows:
The test should be repeated a number of times at each frame rate.
The number of repeats SHOULD be configured by the tester and reported
with the results. The default value is 10 (pulled out of a hat).
The exit criteria of loss free transmissions SHOULD be configured by
the tester and reported with the results. The default value is 10
(also pulled out of a hat).
28.4. Back-to-back frames
The advice on back-to-back frames provided in Section 26.4 of
[RFC2544] applies.
28.5. System Recovery
The advice on system recovery frames provided in Section 26.5 of
[RFC2544] applies.
28.6. Reset
The advice provided in Section 26.6 of [RFC2544] on reset SHOULD be
followed, except that the test MUST NOT be carried out on a DUT that
is being used for production traffic unless a specific decision is
made that disruption of the user traffic is acceptable. This test
MAY be carried out during the quiet period.
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29. IANA considerations
There are no IANA considerations which arise from this document.
30. Security considerations
To be provided in a future version.
31. Acknowledgments
The Authors of [RFC2544] are acknowledged.
32. Informative References
[RFC2119] Bradner, S., "Key words for use in RFCs to Indicate
Requirement Levels", BCP 14, RFC 2119, March 1997.
[RFC2544] Bradner, S. and J. McQuaid, "Benchmarking Methodology for
Network Interconnect Devices", RFC 2544, March 1999.
[RFC3985] Bryant, S. and P. Pate, "Pseudo Wire Emulation Edge-to-
Edge (PWE3) Architecture", RFC 3985, March 2005.
[RFC5921] Bocci, M., Bryant, S., Frost, D., Levrau, L., and L.
Berger, "A Framework for MPLS in Transport Networks",
RFC 5921, July 2010.
Appendix A. Testing Considerations
This Appendix will be deleted or updated in next version. Text is a
copy of Appendix A of [RFC2544]
A.1 Scope Of This Appendix
This appendix discusses certain issues in the benchmarking
methodology where experience or judgment may play a role in the tests
selected to be run or in the approach to constructing the test with a
particular DUT. As such, this appendix MUST not be read as an
amendment to the methodology described in the body of this document
but as a guide to testing practice.
1. Typical testing practice has been to enable all protocols to be
tested and conduct all testing with no further configuration of
protocols, even though a given set of trials may exercise only one
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protocol at a time. This minimizes the opportunities to "tune" a DUT
for a single protocol.
2. The least common denominator of the available filter functions
should be used to ensure that there is a basis for comparison between
vendors. Because of product differences, those conducting and
evaluating tests must make a judgment about this issue.
3. Architectural considerations may need to be considered. For
example, first perform the tests with the stream going between ports
on the same interface card and the repeat the tests with the stream
going into a port on one interface card and out of a port on a second
interface card. There will almost always be a best case and worst
case configuration for a given DUT architecture.
4. Testing done using traffic streams consisting of mixed protocols
has not shown much difference between testing with individual
protocols. That is, if protocol A testing and protocol B testing
give two different performance results, mixed protocol testing
appears to give a result which is the average of the two.
5. Wide Area Network (WAN) performance may be tested by setting up
two identical devices connected by the appropriate short- haul
versions of the WAN modems. Performance is then measured between a
LAN interface on one DUT to a LAN interface on the other DUT.
The maximum frame rate to be used for LAN-WAN-LAN configurations is a
judgment that can be based on known characteristics of the overall
system including compression effects, fragmentation, and gross link
speeds. Practice suggests that the rate should be at least 110% of
the slowest link speed. Substantive issues of testing compression
itself are beyond the scope of this document.]
Appendix B. Maximum frame rates refer
This Appendix will be updated looks updated in next version. Text is
a copy of Appendix B of [RFC2544]
(Provided by Roger Beeman, Cisco Systems)
Size Ethernet 16Mb Token Ring FDDI (bytes) (pps) (pps) (pps)
64 14880 24691 152439 128 8445 13793 85616 256 4528 7326 45620 512
2349 3780 23585 768 1586 2547 15903 1024 1197 1921 11996 1280 961
1542 9630 1518 812 1302 8138
Ethernet size Preamble 64 bits Frame 8 x N bits Gap 96 bits
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16Mb Token Ring size SD 8 bits AC 8 bits FC 8 bits DA 48 bits SA 48
bits RI 48 bits ( 06 30 00 12 00 30 ) SNAP DSAP 8 bits SSAP 8 bits
Control 8 bits Vendor 24 bits Type 16 bits Data 8 x ( N - 18) bits
FCS 32 bits ED 8 bits FS 8 bits
Tokens or idles between packets are not included
FDDI size Preamble 64 bits SD 8 bits FC 8 bits DA 48 bits SA 48 bits
SNAP
DSAP 8 bits SSAP 8 bits Control 8 bits Vendor 24 bits Type 16 bits
Data 8 x ( N - 18) bits FCS 32 bits ED 4 bits FS 12 bits
Appendix C. Test Frame Formats
The considerations provided in Apendix C of [RFC2544] apply.
The requirement for any new frame formats will be considered in a
future version.
Authors' Addresses
Ronald Bonica
Juniper Networks
Email: rbonica@juniper.net
Stewart Bryant
Cisco Systems
Green Park, 250, Longwater Avenue,
Reading RG2 6GB
UK
Email: stbryant@cisco.com
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