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'ETYPES' ** Downref: Normative reference to an Informational draft: draft-brockners-inband-oam-requirements (ref. 'I-D.brockners-inband-oam-requirements') == Outdated reference: A later version (-17) exists of draft-ietf-ippm-ioam-data-00 == Outdated reference: A later version (-16) exists of draft-ietf-nvo3-geneve-05 ** Downref: Normative reference to an Informational RFC: RFC 3232 == Outdated reference: A later version (-05) exists of draft-brockners-proof-of-transit-03 Summary: 2 errors (**), 0 flaws (~~), 9 warnings (==), 4 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group F. Brockners 3 Internet-Draft S. Bhandari 4 Intended status: Standards Track V. Govindan 5 Expires: May 3, 2018 C. Pignataro 6 Cisco 7 H. Gredler 8 RtBrick Inc. 9 J. Leddy 10 Comcast 11 S. Youell 12 JMPC 13 T. Mizrahi 14 Marvell 15 D. Mozes 16 Mellanox Technologies Ltd. 17 P. Lapukhov 18 Facebook 19 R. Chang 20 Barefoot Networks 21 October 30, 2017 23 Geneve encapsulation for In-situ OAM Data 24 draft-brockners-nvo3-ioam-geneve-00 26 Abstract 28 In-situ Operations, Administration, and Maintenance (IOAM) records 29 operational and telemetry information in the packet while the packet 30 traverses a path between two points in the network. This document 31 outlines how IOAM data fields are encapsulated in Geneve. 33 Status of This Memo 35 This Internet-Draft is submitted in full conformance with the 36 provisions of BCP 78 and BCP 79. 38 Internet-Drafts are working documents of the Internet Engineering 39 Task Force (IETF). Note that other groups may also distribute 40 working documents as Internet-Drafts. The list of current Internet- 41 Drafts is at http://datatracker.ietf.org/drafts/current/. 43 Internet-Drafts are draft documents valid for a maximum of six months 44 and may be updated, replaced, or obsoleted by other documents at any 45 time. It is inappropriate to use Internet-Drafts as reference 46 material or to cite them other than as "work in progress." 48 This Internet-Draft will expire on May 3, 2018. 50 Copyright Notice 52 Copyright (c) 2017 IETF Trust and the persons identified as the 53 document authors. All rights reserved. 55 This document is subject to BCP 78 and the IETF Trust's Legal 56 Provisions Relating to IETF Documents 57 (http://trustee.ietf.org/license-info) in effect on the date of 58 publication of this document. Please review these documents 59 carefully, as they describe your rights and restrictions with respect 60 to this document. Code Components extracted from this document must 61 include Simplified BSD License text as described in Section 4.e of 62 the Trust Legal Provisions and are provided without warranty as 63 described in the Simplified BSD License. 65 Table of Contents 67 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 68 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 69 2.1. Requirement Language . . . . . . . . . . . . . . . . . . 3 70 2.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 3 71 3. IOAM Data Field Encapsulation in Geneve . . . . . . . . . . . 3 72 3.1. IOAM Trace Data in Geneve . . . . . . . . . . . . . . . . 3 73 3.2. IOAM POT Data in Geneve . . . . . . . . . . . . . . . . . 7 74 3.3. IOAM Edge-to-Edge Data in Geneve . . . . . . . . . . . . 8 75 4. Discussion of the encapsulation approach . . . . . . . . . . 9 76 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 77 6. Security Considerations . . . . . . . . . . . . . . . . . . . 10 78 7. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 11 79 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 80 8.1. Normative References . . . . . . . . . . . . . . . . . . 11 81 8.2. Informative References . . . . . . . . . . . . . . . . . 12 82 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 84 1. Introduction 86 In-situ OAM (IOAM) records OAM information within the packet while 87 the packet traverses a particular network domain. The term "in-situ" 88 refers to the fact that the IOAM data fields are added to the data 89 packets rather than is being sent within packets specifically 90 dedicated to OAM. This document defines how IOAM data fields are 91 transported as part of the Geneve [I-D.ietf-nvo3-geneve] 92 encapsulation. The IOAM data fields are defined in 93 [I-D.ietf-ippm-ioam-data]. 95 2. Conventions 97 2.1. Requirement Language 99 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 100 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 101 document are to be interpreted as described in [RFC2119]. 103 2.2. Abbreviations 105 Abbreviations used in this document: 107 IOAM: In-situ Operations, Administration, and Maintenance 109 MTU: Maximum Transmit Unit 111 OAM: Operations, Administration, and Maintenance 113 POT: Proof of Transit 115 Geneve: Generic Network Virtualization Encapsulation 117 3. IOAM Data Field Encapsulation in Geneve 119 For encapsulating IOAM data fields into Geneve [I-D.ietf-nvo3-geneve] 120 the different IOAM data fields are included in the Geneve header 121 using tunnel options. IOAM data fields use a tunnel option class 122 which includes the different types of IOAM data, including trace 123 data, proof-of-transit data, and edge-to-edge data. In an 124 administrative domain where IOAM is used, insertion of the IOAM 125 tunnel option(s) in Geneve is enabled at the Geneve tunnel endpoints 126 which also serve as IOAM encapsulating/decapsulating nodes by means 127 of configuration. The Geneve header is defined in 128 [I-D.ietf-nvo3-geneve]. IOAM specific fields for Geneve are defined 129 in this document. 131 3.1. IOAM Trace Data in Geneve 133 IOAM tracing data represents data that is inserted at nodes that a 134 packet traverses. To allow for optimal implementations in both 135 software as well as hardware forwarders, two different ways to 136 encapsulate IOAM data are defined: "Pre-allocated" and "incremental". 137 See [I-D.ietf-ippm-ioam-data] for details on IOAM tracing and the 138 pre-allocated and incremental IOAM trace options. 140 The packet formats of the pre-allocated IOAM trace and incremental 141 IOAM trace when encapsulated in Geneve are defined as below. 143 0 1 2 3 144 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 145 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+ 146 |Ver| Opt Len |O|C| Rsvd. | Protocol Type | | 147 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hdr 148 | Virtual Network Identifier (VNI) | Reserved | | 149 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+ 150 | Option Class = IOAM_Trace |Type (prealloc)|R|R|R| Length | | 151 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IOAM 152 | IOAM-Trace-Type |NodeLen| Flags | Octets-left | Trace 153 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+ 154 | | | 155 | node data list [0] | IOAM 156 | | | 157 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ D 158 | | a 159 | node data list [1] | t 160 | | a 161 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 162 ~ ... ~ S 163 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ p 164 | | a 165 | node data list [n-1] | c 166 | | e 167 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 168 | | | 169 | node data list [n] | | 170 | | | 171 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-<--+ 172 | | 173 | | 174 | Payload + Padding (L2/L3/ESP/...) | 175 | | 176 | | 177 | | 178 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 179 Pre-allocated Trace Option Data MUST be 4-octet aligned. 181 Figure 1: IOAM Pre-allocated Trace Option Format as a Geneve Tunnel 182 Option 184 0 1 2 3 185 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 186 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+ 187 |Ver| Opt Len |O|C| Rsvd. | Protocol Type | | 188 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hdr 189 | Virtual Network Identifier (VNI) | Reserved | | 190 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+ 191 | Option Class = IOAM_Trace | Type (incr.) |R|R|R| Length | | 192 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IOAM 193 | IOAM-Trace-Type |NodeLen| Flags | Max Length | Trace 194 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+ 195 | | | 196 | node data list [0] | IOAM 197 | | | 198 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ D 199 | | a 200 | node data list [1] | t 201 | | a 202 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 203 ~ ... ~ S 204 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ p 205 | | a 206 | node data list [n-1] | c 207 | | e 208 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 209 | | | 210 | node data list [n] | | 211 | | | 212 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-<--+ 213 | | 214 | | 215 | Payload + Padding (L2/L3/ESP/...) | 216 | | 217 | | 218 | | 219 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 220 IOAM Incremental Trace Option Data MUST be 4-octet aligned. 222 Figure 2: IOAM Incremental Trace Option Format as a Geneve Tunnel 223 Option 225 The IOAM Trace header consists of 8 octets, as illustrated in 226 Figure 1 and Figure 2. The first 4 octets are the Geneve Tunnel 227 Option header [I-D.ietf-nvo3-geneve]. The next 4 octets are the 228 trace option header; its format is defined in 229 [I-D.ietf-ippm-ioam-data], and is described here for the sake of 230 clarity. 232 0 1 2 3 233 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 234 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 235 | Option Class = IOAM_Trace | Type |R|R|R| Length | 236 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 238 Figure 3: Geneve Tunnel Option for IOAM 240 The fields of the Geneve tunnel option are as follows: 242 Option Class: 16-bit unsigned integer that determines the IOAM 243 option class. The value is from the IANA registry setup for 244 Geneve option classes as defined in [I-D.ietf-nvo3-geneve]. 246 Type: 8-bit unsigned integer defining IOAM header type. Two values 247 are defined here: IOAM_TRACE_Preallocated and 248 IOAM_Trace_Incremental. 250 R (3 bits): Option control flags reserved for future use. MUST be 251 zero on transmission and ignored on receipt. 253 Length: 5-bit unsigned integer. Length of the IOAM HDR in 4-octet 254 units. 256 The fields of the trace option header [I-D.ietf-ippm-ioam-data] are 257 as follows: 259 IOAM-Trace-Type: 16-bit identifier of IOAM Trace Type as defined in 260 [I-D.ietf-ippm-ioam-data] IOAM-Trace-Types. 262 Node Data Length: 4-bit unsigned integer as defined in 263 [I-D.ietf-ippm-ioam-data]. 265 Flags: 5-bit field as defined in [I-D.ietf-ippm-ioam-data]. 267 Octets-left: 7-bit unsigned integer as defined in 268 [I-D.ietf-ippm-ioam-data]. 270 Maximum-length: 7-bit unsigned integer as defined in 271 [I-D.ietf-ippm-ioam-data]. 273 Node data List [n]: Variable-length field as defined in 274 [I-D.ietf-ippm-ioam-data]. 276 3.2. IOAM POT Data in Geneve 278 IOAM proof of transit (POT, see also 279 [I-D.brockners-proof-of-transit]) offers a means to verify that a 280 packet has traversed a defined set of nodes. IOAM POT data fields 281 are encapsulated in Geneve as follows: 283 0 1 2 3 284 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 285 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+ 286 |Ver| Opt Len |O|C| Rsvd. | Protocol Type | | 287 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hdr 288 | Virtual Network Identifier (VNI) | Reserved | | 289 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+ 290 | Option Class = IOAM_POT | Type |P|R|R|R| Length | | 291 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IOAM 292 | Random | | 293 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ P 294 | Random(contd.) | O 295 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ T 296 | Cumulative | | 297 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ | 298 | Cumulative (contd.) | | 299 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+ 301 Figure 4: IOAM POT Header Following using a Geneve Tunnel Option 303 The first 4 octets of the IOAM POT are the Geneve tunnel option 304 header (Figure 5), which includes the following fields: 306 Option Class: 16-bit unsigned integer that determines the IOAM_POT 307 option class.The value is from the IANA registry setup for Geneve 308 option classes as defined in [I-D.ietf-nvo3-geneve]. 310 Type: 7-bit identifier of a particular POT variant that specifies 311 the POT data that is to be included as defined in 312 [I-D.ietf-ippm-ioam-data]. 314 Profile to use (P): 1-bit as defined in [I-D.ietf-ippm-ioam-data] 315 IOAM POT Option. 317 R (3 bits): Option control flags reserved for future use. MUST be 318 zero on transmission and ignored on receipt. 320 Length: 5-bit unsigned integer. Length of the IOAM HDR in 4-octet 321 units. 323 0 1 2 3 324 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 325 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 326 | Option Class = IOAM_POT | Type |P|R|R|R| Length | 327 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 329 Figure 5: Geneve Tunnel Option for IOAM POT 331 The rest of the fields in the POT option [I-D.ietf-ippm-ioam-data] 332 are as follows: 334 Random: 64-bit Per-packet random number. 336 Cumulative: 64-bit Cumulative value that is updated by the Service 337 Functions. 339 3.3. IOAM Edge-to-Edge Data in Geneve 341 The IOAM edge-to-edge option is to carry data that is added by the 342 IOAM encapsulating node and interpreted by the IOAM decapsulating 343 node. IOAM specific fields to encapsulate IOAM Edge-to-Edge data 344 fields are defined as follows: 346 0 1 2 3 347 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 348 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+ 349 |Ver| Opt Len |O|C| Rsvd. | Protocol Type | | 350 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ Hdr 351 | Virtual Network Identifier (VNI) | Reserved | | 352 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+--+ 353 | Option Class = IOAM_E2E | Type |R|R|R| Length | | 354 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ IOAM 355 | E2E Option data field determined by IOAM-E2E-Type | | 356 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+<-+ 358 Figure 6: IOAM Edge-to-Edge using a Geneve Tunnel Option 360 The first 4 octets of the IOAM E2E option are the Geneve tunnel 361 option header (Figure 5), which includes the following fields: 363 Option Class 16-bit unsigned integer that determines the IOAM_E2E 364 option class.The value is from the IANA registry setup for Geneve 365 option classes as defined in [I-D.ietf-nvo3-geneve]. 367 Type: 8-bit identifier of a particular E2E variant that specifies 368 the E2E data that is included as defined in 369 [I-D.ietf-ippm-ioam-data]. 371 R (3 bits): Option control flags reserved for future use. MUST be 372 zero on transmission and ignored on receipt. 374 Length: 5-bit unsigned integer. Length of the IOAM HDR in 4-octet 375 units. 377 0 1 2 3 378 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 379 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 380 | Option Class = IOAM_E2E | Type |R|R|R| Length | 381 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 383 Figure 7: Geneve Tunnel Option for IOAM E2E 385 The rest of the E2E option [I-D.ietf-ippm-ioam-data] consists of: 387 E2E Option data field: Variable length field as defined in 388 [I-D.ietf-ippm-ioam-data] IOAM E2E Option. 390 4. Discussion of the encapsulation approach 392 This section is to support the working group discussion in selecting 393 the most appropriate approach for encapsulating IOAM data fields in 394 Geneve. 396 An encapsulation of IOAM data fields in Geneve should be friendly to 397 an implementation in both hardware as well as software forwarders and 398 support a wide range of deployment cases, including large networks 399 that desire to leverage multiple IOAM data fields at the same time. 401 Hardware and software friendly implementation: Hardware forwarders 402 benefit from an encapsulation that minimizes iterative look-ups of 403 fields within the packet: Any operation which looks up the value 404 of a field within the packet, based on which another lookup is 405 performed, consumes additional gates and time in an implementation 406 - both of which are desired to be kept to a minimum. This means 407 that flat TLV structures are to be preferred over nested TLV 408 structures. IOAM data fields are grouped into three option 409 categories: Trace, proof-of-transit, and edge-to-edge. Each of 410 these three options defines a TLV structure. A hardware-friendly 411 encapsulation approach avoids grouping these three option 412 categories into yet another TLV structure, but would rather carry 413 the options as a serial sequence. 415 Total length of the IOAM data fields: The total length of IOAM 416 data can grow quite large in case multiple different IOAM data 417 fields are used and large path-lengths need to be considered. If 418 for example an operator would consider using the IOAM trace option 419 and capture node-id, app_data, egress/ingress interface-id, 420 timestamp seconds, timestamps nanoseconds at every hop, then a 421 total of 20 octets would be added to the packet at every hop. In 422 case this particular deployment would have a maximum path length 423 of 15 hops in the IOAM domain, then a maximum of 300 octets of 424 IOAM data were to be encapsulated in the packet. 426 Concerns with the current encapsulation approach: 428 Hardware support: Using Geneve tunnel options to encapsulate IOAM 429 data fields leads to a nested TLV structure. Each IOAM data field 430 option (trace, proof-of-transit, and edge-to-edge) represents a 431 type, with the different IOAM data fields being TLVs within this 432 the particular option type. Nested TLVs require iterative look- 433 ups, a fact that creates potential challenges for implementations 434 in hardware. It would be desirable to offer a way to encapsulate 435 IOAM in a way that keeps TLV nesting to a minimum. 437 Length: Geneve tunnel option length is a 5-bit field in the 438 current specification [I-D.ietf-nvo3-geneve] resulting in a 439 maximum option length of 128 (2^5 x 4) octets which constrains the 440 use of IOAM to either small domains or a few IOAM data fields 441 only. Support for large domains with a variety of IOAM data 442 fields would be desirable. 444 5. IANA Considerations 446 IANA is requested to allocate a Geneve "option class" numbers for the 447 following IOAM types: 449 +---------------+-------------+---------------+ 450 | Option Class | Description | Reference | 451 +---------------+-------------+---------------+ 452 | x | IOAM_Trace | This document | 453 | y | IOAM_POT | This document | 454 | z | IOAM_E2E | This document | 455 +---------------+-------------+---------------+ 457 6. Security Considerations 459 The security considerations of Geneve are discussed in 460 [I-D.ietf-nvo3-geneve], and the security considerations of IOAM in 461 general are discussed in [I-D.ietf-ippm-ioam-data]. 463 IOAM is considered a "per domain" feature, where one or several 464 operators decide on leveraging and configuring IOAM according to 465 their needs. Still, operators need to properly secure the IOAM 466 domain to avoid malicious configuration and use, which could include 467 injecting malicious IOAM packets into a domain. 469 7. Acknowledgements 471 The authors would like to thank Eric Vyncke, Nalini Elkins, Srihari 472 Raghavan, Ranganathan T S, Karthik Babu Harichandra Babu, Akshaya 473 Nadahalli, Stefano Previdi, Hemant Singh, Erik Nordmark, LJ Wobker, 474 and Andrew Yourtchenko for the comments and advice. 476 8. References 478 8.1. Normative References 480 [ETYPES] "IANA Ethernet Numbers", 481 . 484 [I-D.brockners-inband-oam-requirements] 485 Brockners, F., Bhandari, S., Dara, S., Pignataro, C., 486 Gredler, H., Leddy, J., Youell, S., Mozes, D., Mizrahi, 487 T., <>, P., and r. remy@barefootnetworks.com, 488 "Requirements for In-situ OAM", draft-brockners-inband- 489 oam-requirements-03 (work in progress), March 2017. 491 [I-D.ietf-ippm-ioam-data] 492 Brockners, F., Bhandari, S., Pignataro, C., Gredler, H., 493 Leddy, J., Youell, S., Mizrahi, T., Mozes, D., Lapukhov, 494 P., Chang, R., and d. daniel.bernier@bell.ca, "Data Fields 495 for In-situ OAM", draft-ietf-ippm-ioam-data-00 (work in 496 progress), September 2017. 498 [I-D.ietf-nvo3-geneve] 499 Gross, J., Ganga, I., and T. Sridhar, "Geneve: Generic 500 Network Virtualization Encapsulation", draft-ietf- 501 nvo3-geneve-05 (work in progress), September 2017. 503 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 504 Requirement Levels", BCP 14, RFC 2119, 505 DOI 10.17487/RFC2119, March 1997, . 508 [RFC2784] Farinacci, D., Li, T., Hanks, S., Meyer, D., and P. 509 Traina, "Generic Routing Encapsulation (GRE)", RFC 2784, 510 DOI 10.17487/RFC2784, March 2000, . 513 [RFC3232] Reynolds, J., Ed., "Assigned Numbers: RFC 1700 is Replaced 514 by an On-line Database", RFC 3232, DOI 10.17487/RFC3232, 515 January 2002, . 517 8.2. Informative References 519 [FD.io] "Fast Data Project: FD.io", . 521 [I-D.brockners-proof-of-transit] 522 Brockners, F., Bhandari, S., Dara, S., Pignataro, C., 523 Leddy, J., Youell, S., Mozes, D., and T. Mizrahi, "Proof 524 of Transit", draft-brockners-proof-of-transit-03 (work in 525 progress), March 2017. 527 [RFC7665] Halpern, J., Ed. and C. Pignataro, Ed., "Service Function 528 Chaining (SFC) Architecture", RFC 7665, 529 DOI 10.17487/RFC7665, October 2015, . 532 Authors' Addresses 534 Frank Brockners 535 Cisco Systems, Inc. 536 Hansaallee 249, 3rd Floor 537 DUESSELDORF, NORDRHEIN-WESTFALEN 40549 538 Germany 540 Email: fbrockne@cisco.com 542 Shwetha Bhandari 543 Cisco Systems, Inc. 544 Cessna Business Park, Sarjapura Marathalli Outer Ring Road 545 Bangalore, KARNATAKA 560 087 546 India 548 Email: shwethab@cisco.com 550 Vengada Prasad Govindan 551 Cisco Systems, Inc. 553 Email: venggovi@cisco.com 554 Carlos Pignataro 555 Cisco Systems, Inc. 556 7200-11 Kit Creek Road 557 Research Triangle Park, NC 27709 558 United States 560 Email: cpignata@cisco.com 562 Hannes Gredler 563 RtBrick Inc. 565 Email: hannes@rtbrick.com 567 John Leddy 568 Comcast 570 Email: John_Leddy@cable.comcast.com 572 Stephen Youell 573 JP Morgan Chase 574 25 Bank Street 575 London E14 5JP 576 United Kingdom 578 Email: stephen.youell@jpmorgan.com 580 Tal Mizrahi 581 Marvell 582 6 Hamada St. 583 Yokneam 20692 584 Israel 586 Email: talmi@marvell.com 588 David Mozes 589 Mellanox Technologies Ltd. 591 Email: davidm@mellanox.com 592 Petr Lapukhov 593 Facebook 594 1 Hacker Way 595 Menlo Park, CA 94025 596 US 598 Email: petr@fb.com 600 Remy Chang 601 Barefoot Networks 602 2185 Park Boulevard 603 Palo Alto, CA 94306 604 US