idnits 2.17.1 draft-morton-bmwg-b2b-frame-00.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- -- The draft header indicates that this document updates RFC2544, but the abstract doesn't seem to directly say this. It does mention RFC2544 though, so this could be OK. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year (Using the creation date from RFC2544, updated by this document, for RFC5378 checks: 1999-03-01) -- The document seems to lack a disclaimer for pre-RFC5378 work, but may have content which was first submitted before 10 November 2008. If you have contacted all the original authors and they are all willing to grant the BCP78 rights to the IETF Trust, then this is fine, and you can ignore this comment. If not, you may need to add the pre-RFC5378 disclaimer. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (October 30, 2017) is 2363 days in the past. Is this intentional? Checking references for intended status: Informational ---------------------------------------------------------------------------- ** Obsolete normative reference: RFC 1944 (Obsoleted by RFC 2544) Summary: 1 error (**), 0 flaws (~~), 1 warning (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group A. Morton 3 Internet-Draft AT&T Labs 4 Updates: 2544 (if approved) October 30, 2017 5 Intended status: Informational 6 Expires: May 3, 2018 8 Updates for the Back-to-back Frame Benchmark in RFC 2544 9 draft-morton-bmwg-b2b-frame-00 11 Abstract 13 Fundamental Benchmarking Methodologies for Network Interconnect 14 Devices of interest to the IETF are defined in RFC 2544. This memo 15 updates the provisions of the test to measure the Back-to-back frames 16 Benchmark of RFC 2544, based on further experience. 18 This memo updates Section 26.4 of RFC 2544. 20 Requirements Language 22 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 23 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 24 document are to be interpreted as described in RFC 2119 [RFC2119]. 26 Status of This Memo 28 This Internet-Draft is submitted in full conformance with the 29 provisions of BCP 78 and BCP 79. 31 Internet-Drafts are working documents of the Internet Engineering 32 Task Force (IETF). Note that other groups may also distribute 33 working documents as Internet-Drafts. The list of current Internet- 34 Drafts is at https://datatracker.ietf.org/drafts/current/. 36 Internet-Drafts are draft documents valid for a maximum of six months 37 and may be updated, replaced, or obsoleted by other documents at any 38 time. It is inappropriate to use Internet-Drafts as reference 39 material or to cite them other than as "work in progress." 41 This Internet-Draft will expire on May 3, 2018. 43 Copyright Notice 45 Copyright (c) 2017 IETF Trust and the persons identified as the 46 document authors. All rights reserved. 48 This document is subject to BCP 78 and the IETF Trust's Legal 49 Provisions Relating to IETF Documents 50 (https://trustee.ietf.org/license-info) in effect on the date of 51 publication of this document. Please review these documents 52 carefully, as they describe your rights and restrictions with respect 53 to this document. Code Components extracted from this document must 54 include Simplified BSD License text as described in Section 4.e of 55 the Trust Legal Provisions and are provided without warranty as 56 described in the Simplified BSD License. 58 Table of Contents 60 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 61 2. Scope and Goals . . . . . . . . . . . . . . . . . . . . . . . 3 62 3. Motivation . . . . . . . . . . . . . . . . . . . . . . . . . 3 63 4. Pre-Requisites . . . . . . . . . . . . . . . . . . . . . . . 4 64 5. Back-to-back Frames . . . . . . . . . . . . . . . . . . . . . 5 65 5.1. Preparing the list of Frame sizes . . . . . . . . . . . . 5 66 5.2. Test for a Single Frame Size . . . . . . . . . . . . . . 5 67 5.3. Test Repetition . . . . . . . . . . . . . . . . . . . . . 6 68 5.4. Benchmark Calculations . . . . . . . . . . . . . . . . . 6 69 6. Reporting . . . . . . . . . . . . . . . . . . . . . . . . . . 6 70 7. Security Considerations . . . . . . . . . . . . . . . . . . . 7 71 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 8 72 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 8 73 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 8 74 10.1. Normative References . . . . . . . . . . . . . . . . . . 8 75 10.2. Informative References . . . . . . . . . . . . . . . . . 9 76 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 9 78 1. Introduction 80 The IETF's fundamental Benchmarking Methodologies are defined 81 in[RFC2544], supported by the terms and definitions in [RFC1242], and 82 [RFC2544] actually obsoletes an earlier specification, [RFC1944]. 83 Over time, the benchmarking community has updated [RFC2544] several 84 times, including the Device Reset Benchmark [RFC6201], and the 85 important Applicability Statement [RFC6815] concerning use outside 86 the Isolated Test Environment (ITE) required for accurate 87 benchmarking. Other specifications implicitly update [RFC2544], such 88 as the IPv6 Benchmarking Methodologies in [RFC5180]. 90 Recent testing experience with the Back-to-back Frame test and 91 Benchmark in Section 26.4 of [RFC2544] indicates that an update is 92 warranted [OPNFV-2017] [VSPERF-b2b]. This memo describes the 93 rationale and provides the updated method. 95 [RFC2544] provides its own Requirements Language consistent with 96 [RFC2119], since [RFC1944] predates [RFC2119]. Thus, the 97 requirements presented in this memo are expressed in [RFC2119] terms, 98 and intended for those performing/reporting laboratory tests to 99 improve clarity and repeatability, and for those designing devices 100 that facilitate these tests. 102 2. Scope and Goals 104 The scope of this memo is to define an updated method to 105 unambiguously perform tests, measure the benchmark(s), and report the 106 results for Back-to-back Frames (presently described Section 26.4 of 107 [RFC2544]). 109 The goal is to provide more efficient test procedures where possible, 110 and to expand reporting with additional interpretation of the 111 results. 113 [RFC2544] Benchmarks rely on test conditions with constant frame 114 sizes, with the goal of understanding what network device capability 115 has been tested. Tests with the smallest size stress the header 116 processing capacity, and tests with the largest size stress the 117 overall bit processing capacity. Tests with sizes in-between may 118 determine the transition between these two capacities. However, 119 conditions simultaneously sending multiple frame sizes, such as those 120 described in [RFC6985], MUST NOT be used in Back-to-back Frame 121 testing. 123 3. Motivation 125 Section 3.1 of [RFC1242] describes the rationale for the Back-to-back 126 Frames Benchmark. To summarize, there are several reasons that 127 devices on a network produce bursts of frames at the minimum allowed 128 spacing, and it is therefore worthwhile to understand the Device 129 Under Test (DUT) limit on the length of such bursts in practice. 130 Also, [RFC1242] states: 132 "Tests of this parameter are intended to determine the extent 133 of data buffering in the device." 135 After this test was defined, there have been occasional discussions 136 of the stability and repeatability of the results, both over time and 137 across labs. Fortunately, the Open Platform for Network Function 138 Virtualization (OPNFV) VSPERF project's Continuous Integration (CI) 139 testing routinely repeats Back-to-back Frame tests to verify that 140 test functionality has been maintained through development of the 141 test control programs. These tests were used as a basis to evaluate 142 stability and repeatability, even across lab set-ups when the test 143 platform was migrated to new DUT hardware at the end of 2016. 145 When the VSPERF CI results were examined [VSPERF-b2b], several 146 aspects of the results were considered notable: 148 1. Back-to-back Frame Benchmark was very consistent for some fixed 149 frame sizes, and somewhat variable for others. 151 2. The Back-to-back Frame length reported for large frame sizes was 152 unexpectedly long, and no explanation or measurement limit 153 condition was indicated. 155 3. Calculation of the extent of buffer time in the DUT helped 156 explain the results with all frame sizes (some frame sizes cannot 157 exceed the frame header processing rate of the DUT, and therefore 158 no buffering occurs). 160 4. It was observed that the actual buffer time in the DUT could be 161 estimated using results from the Throughput tests conducted 162 according to Section 26.1 of [RFC2544]. 164 Further, if the Throughput tests of Section 26.1 of [RFC2544] are 165 conducted as a pre-requiste test, the number of frame sizes required 166 for Back-to-back Frame Benchmarking can be reduced to one or more of 167 the small frame sizes, or results for large frame sizes can be noted 168 as invalid in the results. 170 [VSPERF-b2b] provides the details of the calculation to estimate the 171 actual buffer time available in the DUT, using results from the 172 Throughput tests for each frame size, and the maximum theoretical 173 frame rate for the DUT links (which constrain the minimum frame 174 spacing). 176 4. Pre-Requisites 178 The Test Setup MUST be consistent with Figure 1 of [RFC2544], or 179 Figure 2 when the tester's sender and reciver are different devices. 180 Other mandatory testing aspects described in [RFC2544] MUST be 181 included, unless explicitly modified in the next section. 183 The ingress and egress link speeds and link layer protocols MUST be 184 specified and used to compute the maximum theoretical frame rate when 185 respecting the minimum inter-frame gap. 187 The test results for the Throughput Benchmark conducted according to 188 Section 26.1 of [RFC2544] for all [RFC2544]-RECOMMENDED frame sizes 189 MUST be available to reduce the tested frame size list, or to note 190 invalid results for individual frame sizes (because the burst length 191 may be infinite for large frame sizes). 193 Note that: 195 o the Throughput and the Back-to-back Frame measurement 196 configuration traffic characteristics (unidirectional or bi- 197 directional) MUST match. 199 o the Throughput measurement MUST be under zero-loss conditions, 200 according to Section 26.1 of [RFC2544]. 202 The Back-to-back Benchmark described in Section 3.1 of [RFC1242] MUST 203 be measured directly by the tester. Additional measurement 204 reuirements are described below in Section 5. 206 5. Back-to-back Frames 208 Objective: To characterize the ability of a DUT to process back-to- 209 back frames as defined in [RFC1242]. 211 The Procedure follows. 213 5.1. Preparing the list of Frame sizes 215 From the list of RECOMMENDED Frame sizes (Section 9 of [RFC2544]), 216 select the subset of Frame sizes whose measured Throughput was less 217 than the maximum theoretical Frame Rate. Only these Frame sizes make 218 it possible to produce a burst of frames that cause the DUT buffers 219 to fill and eventually overflow, producing one or more discarded 220 frames. 222 5.2. Test for a Single Frame Size 224 Each trial in the test requires the tester to send a burst of frames 225 (after idle time) with the minimum inter-frame gap, and to count the 226 frames forwarded by the DUT. 228 The duration of the trial MUST be at least 2 seconds, to allow DUT 229 buffers to deplete. 231 If all frames have been received, the tester increases the length of 232 the burst and performs another trial. 234 If the received frame count is less than the number of frames in the 235 burst, then the limit of DUT processing and buffering may have been 236 exceeded, and the burst length is reduced for the next trial. 238 @@@@ Should a particular search algorithm be included? 240 The Back-to-back Frame value is the longest burst of frames that the 241 DUT can successfully process and buffer without frame loss, as 242 determined from the series of trials. The tester may impose a 243 (configurable) minimum step size for burst length, and the step size 244 MUST be reported with the results (as this influences the accuracy 245 and variation of test results). 247 5.3. Test Repetition 249 The test MUST be repeated N times for each frame size in the subset 250 list, and each Back-to-back Frame value made available for further 251 processing (below). 253 5.4. Benchmark Calculations 255 For each Frame size, calculate the following summary statistics for 256 Back-to-back Frame values over the N tests: 258 o Average (Benchmark) 260 o Minimum 262 o Maximum 264 o Standard Deviation 266 Further, calculate the Implied DUT Buffer Time and the Corrected DUT 267 Buffer Time in seconds, as follows: 269 Implied DUT Buffer Time = 271 Average Back-to-back Frames / Max Theoretical Frame Rate 273 Corrected DUT Buffer Time = 275 Measured Throughput 276 Implied DUT Buffer Time * -------------------------- 277 Max Theoretical Frame Rate 279 6. Reporting 281 The back-to-back results SHOULD be reported in the format of a table 282 with a row for each of the tested frame sizes. There SHOULD be 283 columns for the frame size and for the resultant average frame count 284 for each type of data stream tested. 286 The number of tests Averaged for the Benchmark, N, MUST be reported. 288 The Minimum, Maximum, and Standard Deviation across all complete 289 tests SHOULD also be reported. 291 The Corrected DUT Buffer Time SHOULD also be reported. 293 If the tester operates using a maximum burst length in frames, then 294 this maximum length SHOULD be reported. 296 +--------------+----------------+----------------+------------------+ 297 | Frame Size, | Ave B2B | Min,Max,StdDev | Corrected Buff | 298 | octets | Length, frames | | Time, Sec | 299 +--------------+----------------+----------------+------------------+ 300 | 64 | 26000 | 25500,27000,20 | 0.00004 | 301 +--------------+----------------+----------------+------------------+ 303 Back-to-Back Frame Results 305 Static and configuration parameters: 307 Number of test repetitions, N 309 Minimum Step Size (during searches), in frames. 311 7. Security Considerations 313 Benchmarking activities as described in this memo are limited to 314 technology characterization using controlled stimuli in a laboratory 315 environment, with dedicated address space and the other constraints 316 [RFC2544]. 318 The benchmarking network topology will be an independent test setup 319 and MUST NOT be connected to devices that may forward the test 320 traffic into a production network, or misroute traffic to the test 321 management network. 323 Further, benchmarking is performed on a "black-box" basis, relying 324 solely on measurements observable external to the DUT/SUT. 326 Special capabilities SHOULD NOT exist in the DUT/SUT specifically for 327 benchmarking purposes. Any implications for network security arising 328 from the DUT/SUT SHOULD be identical in the lab and in production 329 networks. 331 8. IANA Considerations 333 This memo makes no requests of IANA. 335 9. Acknowledgements 337 Thanks to Trevor Cooper, Sridhar Rao, and Martin Klozik of the VSPERF 338 project for many contributions to the testing [VSPERF-b2b]. 340 10. References 342 10.1. Normative References 344 [RFC1242] Bradner, S., "Benchmarking Terminology for Network 345 Interconnection Devices", RFC 1242, DOI 10.17487/RFC1242, 346 July 1991, . 348 [RFC1944] Bradner, S. and J. McQuaid, "Benchmarking Methodology for 349 Network Interconnect Devices", RFC 1944, 350 DOI 10.17487/RFC1944, May 1996, 351 . 353 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 354 Requirement Levels", BCP 14, RFC 2119, 355 DOI 10.17487/RFC2119, March 1997, 356 . 358 [RFC2544] Bradner, S. and J. McQuaid, "Benchmarking Methodology for 359 Network Interconnect Devices", RFC 2544, 360 DOI 10.17487/RFC2544, March 1999, 361 . 363 [RFC5180] Popoviciu, C., Hamza, A., Van de Velde, G., and D. 364 Dugatkin, "IPv6 Benchmarking Methodology for Network 365 Interconnect Devices", RFC 5180, DOI 10.17487/RFC5180, May 366 2008, . 368 [RFC6201] Asati, R., Pignataro, C., Calabria, F., and C. Olvera, 369 "Device Reset Characterization", RFC 6201, 370 DOI 10.17487/RFC6201, March 2011, 371 . 373 [RFC6815] Bradner, S., Dubray, K., McQuaid, J., and A. Morton, 374 "Applicability Statement for RFC 2544: Use on Production 375 Networks Considered Harmful", RFC 6815, 376 DOI 10.17487/RFC6815, November 2012, 377 . 379 [RFC6985] Morton, A., "IMIX Genome: Specification of Variable Packet 380 Sizes for Additional Testing", RFC 6985, 381 DOI 10.17487/RFC6985, July 2013, 382 . 384 10.2. Informative References 386 [OPNFV-2017] 387 Cooper, T., "Dataplane Performance, Capacity, and 388 Benchmarking in OPNFV", June 2017. 390 [VSPERF-b2b] 391 Morton, A., "Back2Back Testing Time Series (from CI)", 392 June 2017. 394 Author's Address 396 Al Morton 397 AT&T Labs 398 200 Laurel Avenue South 399 Middletown,, NJ 07748 400 USA 402 Phone: +1 732 420 1571 403 Fax: +1 732 368 1192 404 Email: acmorton@att.com