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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Outdated reference: A later version (-17) exists of draft-ietf-ippm-ioam-data-15 == Outdated reference: A later version (-12) exists of draft-ietf-ippm-ioam-ipv6-options-06 == Outdated reference: A later version (-13) exists of draft-ietf-sfc-ioam-nsh-06 == Outdated reference: A later version (-07) exists of draft-spiegel-ippm-ioam-rawexport-05 Summary: 0 errors (**), 0 flaws (~~), 5 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 IPPM T. Mizrahi 3 Internet-Draft Huawei 4 Intended status: Standards Track F. Brockners 5 Expires: April 16, 2022 Cisco 6 S. Bhandari, Ed. 7 Thoughtspot 8 R. Sivakolundu 9 C. Pignataro 10 Cisco 11 A. Kfir 12 B. Gafni 13 Nvidia 14 M. Spiegel 15 Barefoot Networks, an Intel company 16 J. Lemon 17 Broadcom 18 October 13, 2021 20 In-situ OAM Loopback and Active Flags 21 draft-ietf-ippm-ioam-flags-07 23 Abstract 25 In-situ Operations, Administration, and Maintenance (IOAM) collects 26 operational and telemetry information in packets while they traverse 27 a path between two points in the network. This document defines two 28 new flags in the IOAM Trace Option headers, specifically the Loopback 29 and Active flags. 31 Status of This Memo 33 This Internet-Draft is submitted in full conformance with the 34 provisions of BCP 78 and BCP 79. 36 Internet-Drafts are working documents of the Internet Engineering 37 Task Force (IETF). Note that other groups may also distribute 38 working documents as Internet-Drafts. The list of current Internet- 39 Drafts is at https://datatracker.ietf.org/drafts/current/. 41 Internet-Drafts are draft documents valid for a maximum of six months 42 and may be updated, replaced, or obsoleted by other documents at any 43 time. It is inappropriate to use Internet-Drafts as reference 44 material or to cite them other than as "work in progress." 46 This Internet-Draft will expire on April 16, 2022. 48 Copyright Notice 50 Copyright (c) 2021 IETF Trust and the persons identified as the 51 document authors. All rights reserved. 53 This document is subject to BCP 78 and the IETF Trust's Legal 54 Provisions Relating to IETF Documents 55 (https://trustee.ietf.org/license-info) in effect on the date of 56 publication of this document. Please review these documents 57 carefully, as they describe your rights and restrictions with respect 58 to this document. Code Components extracted from this document must 59 include Simplified BSD License text as described in Section 4.e of 60 the Trust Legal Provisions and are provided without warranty as 61 described in the Simplified BSD License. 63 Table of Contents 65 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 66 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 67 2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 68 2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 69 3. New IOAM Trace Option Flags . . . . . . . . . . . . . . . . . 3 70 4. Loopback in IOAM . . . . . . . . . . . . . . . . . . . . . . 3 71 4.1. Loopback: Encapsulating Node Functionality . . . . . . . 4 72 4.1.1. Loopback Packet Selection . . . . . . . . . . . . . . 5 73 4.2. Receiving and Processing Loopback . . . . . . . . . . . . 6 74 4.3. Loopback on the Return Path . . . . . . . . . . . . . . . 7 75 4.4. Terminating a Looped Back Packet . . . . . . . . . . . . 7 76 5. Active Measurement with IOAM . . . . . . . . . . . . . . . . 7 77 6. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 78 7. Performance Considerations . . . . . . . . . . . . . . . . . 9 79 8. Security Considerations . . . . . . . . . . . . . . . . . . . 10 80 9. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 11 81 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 82 10.1. Normative References . . . . . . . . . . . . . . . . . . 11 83 10.2. Informative References . . . . . . . . . . . . . . . . . 12 84 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 12 86 1. Introduction 88 IOAM [I-D.ietf-ippm-ioam-data] is used for monitoring traffic in the 89 network by incorporating IOAM data fields into in-flight data 90 packets. 92 IOAM data may be represented in one of four possible IOAM options: 93 Pre-allocated Trace Option, Incremental Trace Option, Proof of 94 Transit (POT) Option, and Edge-to-Edge Option. This document defines 95 two new flags in the Pre-allocated and Incremental Trace options: the 96 Loopback and Active flags. 98 The Loopback flag is used to request that each transit device along 99 the path loops back a truncated copy of the data packet to the 100 sender. The Active flag indicates that a packet is used for active 101 measurement. The term active measurement in the context of this 102 document is as defined in [RFC7799]. 104 2. Conventions 106 2.1. Requirements Language 108 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 109 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 110 "OPTIONAL" in this document are to be interpreted as described in BCP 111 14 [RFC2119] [RFC8174] when, and only when, they appear in all 112 capitals, as shown here. 114 2.2. Terminology 116 Abbreviations used in this document: 118 IOAM: In-situ Operations, Administration, and Maintenance 120 OAM: Operations, Administration, and Maintenance 122 3. New IOAM Trace Option Flags 124 This document defines two new flags in the Pre-allocated and 125 Incremental Trace options: 127 Bit 1 "Loopback" (L-bit). When set, the Loopback flag triggers 128 sending a copy of a packet back towards the source, as further 129 described in Section 4. 131 Bit 2 "Active" (A-bit). When set, the Active flag indicates that a 132 packet is an active measurement packet rather than a data packet, 133 where "active" is used in the sense defined in [RFC7799]. The 134 packet may be an IOAM probe packet, or a replicated data packet 135 (the second and third use cases of Section 5). 137 4. Loopback in IOAM 139 The Loopback flag is used to request that each transit device along 140 the path loops back a truncated copy of the data packet to the 141 sender. Loopback allows an IOAM encapsulating node to trace the path 142 to a given destination, and to receive per-hop data about both the 143 forward and the return path. Loopback is intended to provide an 144 accelerated alternative to Traceroute, that allows the encapsulating 145 node to receive responses from multiple transit nodes along the path 146 in less then one round-trip-time, and by sending a single packet. 148 As illustrated in Figure 1, an IOAM encapsulating node can push an 149 IOAM encapsulation that includes the Loopback flag onto some or all 150 of the packets it forwards. The IOAM transit node and the 151 decapsulating node both creates copies of the packet and loop them 152 back to the encapsulating node. The decapsulating node also 153 terminates the IOAM encapsulation, and then forwards the packet 154 towards the destination. The two IOAM looped back copies are 155 terminated by the encapsulating node. 157 +--------+ +--------+ +--------+ +--------+ +--------+ 158 | | | IOAM |.....| IOAM |.....| IOAM | | | 159 +--------+ +--------+ +--------+ +--------+ +--------+ 160 | L2/L3 |<===>| L2/L3 |<===>| L2/L3 |<===>| L2/L3 |<===>| L2/L3 | 161 +--------+ +--------+ +--------+ +--------+ +--------+ 162 Source Encapsulating Transit Decapsulating Destination 163 Node Node Node 165 <------------ IOAM domain -----------> 167 IOAM encap. with Loopback flag 168 Data packet ------->============================>-----------> 169 | | 170 IOAM looped back | | 171 <=============+ | 172 IOAM looped back| 173 <===========================+ 175 Figure 1: Loopback in IOAM. 177 Loopback can be used only if a return path from transit nodes and 178 destination nodes towards the source (encapsulating node) exists. 179 Specifically, loopback is only applicable in encapsulations in which 180 the identity of the encapsulating node is available in the 181 encapsulation header. If an encapsulating node receives a looped 182 back packet that was not originated from the current encapsulating 183 node, the packet is dropped. 185 4.1. Loopback: Encapsulating Node Functionality 187 The encapsulating node either generates synthetic packets with an 188 IOAM trace option that has the Loopback flag set, or sets the loopack 189 flag in a subset of the in-transit data packets. Loopback is used 190 either proactively or on-demand, i.e., when a failure is detected. 191 The encapsulating node also needs to ensure that sufficient space is 192 available in the IOAM header for loopback operation, which includes 193 transit nodes adding trace data on the original path and then again 194 on the return path. 196 An IOAM trace option that has the Loopback flag set MUST have the 197 value '1' in the most significant bit of IOAM-Trace-Type, and '0' in 198 the rest of the bits of IOAM-Trace-Type. Thus, every transit node 199 that processes this trace option only adds a single data field, which 200 is the Hop_Lim and node_id data field. A transit node that receives 201 a packet with an IOAM trace option that has the Loopback flag set and 202 the IOAM-Trace-Type is not equal to '1' in the most significant bit 203 and '0' in the rest of the bits, MUST NOT loop back a copy of the 204 packet. The reason for allowing a single data field per hop is to 205 minimize the impact of amplification attacks. 207 IOAM encapsulating nodes MUST NOT push an IOAM encapsulation with the 208 Loopback flag onto data packets that already include an IOAM 209 encapsulation. This requirement is intended to prevent IOAM Loopback 210 nesting, where looped back packets may be subject to loopback in a 211 nested IOAM domain. 213 4.1.1. Loopback Packet Selection 215 If an IOAM encapsulating node incorporates the Loopback flag into all 216 the traffic it forwards it may lead to an excessive amount of looped 217 back packets, which may overload the network and the encapsulating 218 node. Therefore, an IOAM encapsulating node that supports the 219 Loopback flag MUST support the ability to incorporate the Loopback 220 flag selectively into a subset of the packets that are forwarded by 221 it. 223 Various methods of packet selection and sampling have been previously 224 defined, such as [RFC7014] and [RFC5475]. Similar techniques can be 225 applied by an IOAM encapsulating node to apply Loopback to a subset 226 of the forwarded traffic. 228 The subset of traffic that is forwarded or transmitted with a 229 Loopback flag SHOULD NOT exceed 1/N of the interface capacity on any 230 of the IOAM encapsulating node's interfaces. It is noted that this 231 requirement applies to the total traffic that incorporates a Loopback 232 flag, including traffic that is forwarded by the IOAM encapsulating 233 node and probe packets that are generated by the IOAM encapsulating 234 node. In this context N is a parameter that can be configurable by 235 network operators. If there is an upper bound, M, on the number of 236 IOAM transit nodes in any path in the network, then it is recommended 237 to use an N such that N >> M. The rationale is that a packet that 238 includes the Loopback flag triggers a looped back packet from each 239 IOAM transit node along the path for a total of M looped back 240 packets. Thus, if N >> M then the number of looped back packets is 241 significantly lower than the number of data packets forwarded by the 242 IOAM encapsulating node. If there is no prior knowledge about the 243 network topology or size, it is recommended to use N>100. 245 The loopback flag MUST NOT be set if it is not guaranteed that there 246 is a return path from each of the IOAM transit and IOAM decapsulating 247 nodes, or if the encapsulating node's identity is not available in 248 the encapsulation header. 250 4.2. Receiving and Processing Loopback 252 A Loopback flag that is set indicates to the transit nodes processing 253 this option that they are to create a copy of the received packet and 254 send the copy back to the source of the packet. In this context the 255 source is the IOAM encapsulating node, and it is assumed that the 256 source address is available in the encapsulation header. Thus, the 257 source address of the original packet is used as the destination 258 address in the copied packet. If the address of the encapsulating 259 node is not available in the encapsulation header, then the transit/ 260 decapsulating node does not loop back a copy of the original packet. 261 The address of the node performing the copy operation is used as the 262 source address. The IOAM transit node pushes the required data field 263 *after* creating the copy of the packet, in order to allow any 264 egress-dependent information to be set based on the egress of the 265 copy rather than the original packet. The copy is also truncated, 266 i.e., any payload that resides after the IOAM option(s) is removed 267 before transmitting the looped back packet back towards the 268 encapsulating node. The original packet continues towards its 269 destination. The L-bit MUST be cleared in the copy of the packet 270 that a node sends back towards the source. 272 An IOAM node that supports the reception and processing of the 273 Loopback flag MUST support the ability to limit the rate of the 274 looped back packets. The rate of looped back packets SHOULD be 275 limited so that the number of looped back packets is significantly 276 lower than the number of packets that are forwarded by the device. 277 The looped back data rate SHOULD NOT exceed 1/N of the interface 278 capacity on any of the IOAM node's interfaces. It is recommended to 279 use N>100. Depending on the IOAM node's architecture considerations, 280 the loopback response rate may be limited to a lower number in order 281 to avoid loading the IOAM node. 283 4.3. Loopback on the Return Path 285 On its way back towards the source, the copied packet is processed 286 like any other packet with IOAM information, including adding any 287 requested data at each transit node (assuming there is sufficient 288 space). 290 4.4. Terminating a Looped Back Packet 292 Once the return packet reaches the IOAM domain boundary, IOAM 293 decapsulation occurs as with any other packet containing IOAM 294 information. Note that the looped back packet does not have the 295 L-bit set. The IOAM encapsulating node that initiated the original 296 loopback packet recognizes a received packet as an IOAM looped-back 297 packet by checking the Node ID in the Hop_Lim/node_id field that 298 corresponds to the first hop. If the Node ID and IOAM-Namespace 299 match the current IOAM node, it indicates that this is a looped back 300 packet that was initiated by the current IOAM node, and processed 301 accordingly. If there is no match in the Node ID, the packet is 302 processed like a conventional IOAM-encapsulated packet. 304 Note that an IOAM encapsulating node may either be an endpoint (such 305 as an IPv6 host), or a switch/router that pushes a tunnel 306 encapsulation onto data packets. In both cases, the functionality 307 that was described above avoids IOAM data leaks from the IOAM domain. 308 Specificallly, if an IOAM looped-back packet reaches an IOAM boundary 309 node that is not the IOAM node that initiated the loopback, the node 310 does not process the packet as a loopback; the IOAM encapsulation is 311 removed, and since the packet does not have any payload it is 312 terminated. In either case, when the packet reaches the IOAM 313 boundary its IOAM encapsulation is removed, preventing IOAM 314 information from leaking out from the IOAM domain. 316 5. Active Measurement with IOAM 318 Active measurement methods [RFC7799] make use of synthetically 319 generated packets in order to facilitate measurement. This section 320 presents use cases of active measurement using the IOAM Active flag. 322 The Active flag indicates that a packet is used for active 323 measurement. An IOAM decapsulating node that receives a packet with 324 the Active flag set in one of its Trace options must terminate the 325 packet. The Active flag is intended to simplify the implementation 326 of decapsulating nodes by indicating that the packet should not be 327 forwarded further. It is not intended as a replacement for existing 328 active OAM protocols, which may run in higher layers and make use of 329 the Active flag. 331 An example of an IOAM deployment scenario is illustrated in Figure 2. 332 The figure depicts two endpoints, a source and a destination. The 333 data traffic from the source to the destination is forwarded through 334 a set of network devices, including an IOAM encapsulating node, which 335 incorporates one or more IOAM options, a decapsulating node, which 336 removes the IOAM options, optionally one or more transit nodes. The 337 IOAM options are encapsulated in one of the IOAM encapsulation types, 338 e.g., [I-D.ietf-sfc-ioam-nsh], or [I-D.ietf-ippm-ioam-ipv6-options]. 340 +--------+ +--------+ +--------+ +--------+ +--------+ 341 | | | IOAM |.....| IOAM |.....| IOAM | | | 342 +--------+ +--------+ +--------+ +--------+ +--------+ 343 | L2/L3 |<===>| L2/L3 |<===>| L2/L3 |<===>| L2/L3 |<===>| L2/L3 | 344 +--------+ +--------+ +--------+ +--------+ +--------+ 345 Source Encapsulating Transit Decapsulating Destination 346 Node Node Node 348 <------------ IOAM domain -----------> 350 Figure 2: Network using IOAM. 352 This draft focuses on three possible use cases of active measurement 353 using IOAM. These use cases are described using the example of 354 Figure 2. 356 o Endpoint active measurement: synthetic probe packets are sent 357 between the source and destination, traversing the IOAM domain. 358 Since the probe packets are sent between the endpoints, these 359 packets are treated as data packets by the IOAM domain, and do not 360 require special treatment at the IOAM layer. Specifically, the 361 Active flag is not used in this case, and the IOAM layer needs not 362 be aware that an active measurement mechanism is used at a higher 363 layer. 365 o IOAM active measurement using probe packets within the IOAM 366 domain: probe packets are generated and transmitted by the IOAM 367 encapsulating node, and are expected to be terminated by the 368 decapsulating node. IOAM data related to probe packets may be 369 exported by one or more nodes along its path, by an exporting 370 protocol that is outside the scope of this document (e.g., 371 [I-D.spiegel-ippm-ioam-rawexport]). Probe packets include a Trace 372 Option which has its Active flag set, indicating that the 373 decapsulating node must terminate them. 375 o IOAM active measurement using replicated data packets: probe 376 packets are created by the encapsulating node by selecting some or 377 all of the en route data packets and replicating them. A selected 378 data packet that is replicated, and its (possibly truncated) copy 379 is forwarded with one or more IOAM option, while the original 380 packet is forwarded normally, without IOAM options. To the extent 381 possible, the original data packet and its replica are forwarded 382 through the same path. The replica includes a Trace Option that 383 has its Active flag set, indicating that the decapsulating node 384 should terminate it. It should be noted that the current document 385 defines the role of the Active flag in allowing the decapsulating 386 node to terminate the packet, but the replication functionality in 387 this context is outside the scope of this document. 389 If the volume of traffic that incorporates the Active flag is large, 390 it may overload the network and the IOAM node(s) that process the 391 active measurement packet. Thus, the rate of the traffic that 392 includes the Active flag rate SHOULD NOT exceed 1/N of the interface 393 capacity on any of the IOAM node's interfaces. It is recommended to 394 use N>100. Depending on the IOAM node's architecture considerations, 395 the rate of Active-enabled IOAM packets may be limited to a lower 396 number in order to avoid loading the IOAM node. 398 6. IANA Considerations 400 IANA is requested to allocate the following bits in the "IOAM Trace 401 Flags Registry" as follows: 403 Bit 1 "Loopback" (L-bit) 405 Bit 2 "Active" (A-bit) 407 Note that bit 0 is the most significant bit in the Flags Registry. 409 7. Performance Considerations 411 Each of the flags that are defined in this document may have 412 performance implications. When using the loopback mechanism a copy 413 of the data packet is sent back to the sender, thus generating more 414 traffic than originally sent by the endpoints. Using active 415 measurement with the Active flag requires the use of synthetic 416 (overhead) traffic. 418 Each of the mechanisms that use the flags above has a cost in terms 419 of the network bandwidth, and may potentially load the node that 420 analyzes the data. Therefore, it MUST be possible to use each of the 421 mechanisms on a subset of the data traffic; an encapsulating node 422 needs to be able to set the Loopback and Active flag selectively, in 423 a way that considers the effect on the network performance, as 424 further discussed in Section 4.1.1 and Section 5. 426 Transit and decapsulating nodes that support Loopback need to be able 427 to limit the looped back packets (Section 4.2) so as to ensure that 428 the mechanisms are used at a rate that does not significantly affect 429 the network bandwidth, and does not overload the source node in the 430 case of loopback. 432 8. Security Considerations 434 The security considerations of IOAM in general are discussed in 435 [I-D.ietf-ippm-ioam-data]. Specifically, an attacker may try to use 436 the functionality that is defined in this document to attack the 437 network. 439 IOAM is assumed to be deployed in a restricted administrative domain, 440 thus limiting the scope of the threats above and their effect. This 441 is a fundamental assumption with respect to the security aspects of 442 IOAM, as further discussed in [I-D.ietf-ippm-ioam-data]. However, 443 even given this limited scope, security threats should still be 444 considered and mitigated. Specifically, an attacker may attempt to 445 overload network devices by injecting synthetic packets that include 446 an IOAM Trace Option with one or more of the flags defined in this 447 document. Similarly, an on-path attacker may maliciously set one or 448 more of the flags of transit packets. 450 o Loopback flag: an attacker that sets this flag, either in 451 synthetic packets or transit packet, can potentially cause an 452 amplification, since each device along the path creates a copy of 453 the data packet and sends it back to the source. The attacker can 454 potentially leverage the Loopback flag for a Distributed Denial of 455 Service (DDoS) attack, as multiple devices send looped-back copies 456 of a packet to a single source. 458 o Active flag: the impact of synthetic packets with the Active flag 459 is no worse than synthetic data packets in which the Active flag 460 is not set. By setting the Active flag in en route packets an 461 attacker can prevent these packets from reaching their 462 destination, since the packet is terminated by the decapsulating 463 device; however, note that an on-path attacker may achieve the 464 same goal by changing the destination address of a packet. 465 Another potential threat is amplification; if an attacker causes 466 transit switches to replicate more packets than they are intended 467 to replicate, either by setting the Active flag or by sending 468 synthetic packets, then traffic is amplified, causing bandwidth 469 degredation. As mentioned in Section 5, the specification of the 470 replication mechanism is not within the scope of this document. A 471 specification that defines the replication functionality should 472 also address the security aspects of this mechanism. 474 Some of the security threats that were discussed in this document may 475 be worse in a wide area network in which there are nested IOAM 476 domains. For example, if there are two nested IOAM domains that use 477 loopback, then a looped-back copy in the outer IOAM domain may be 478 forwarded through another (inner) IOAM domain and may be subject to 479 loopback in that (inner) IOAM domain, causing the amplification to be 480 worse than in the conventional case. 482 In order to mitigate the performance-related attacks described above, 483 as described in Section 7 it should be possible for IOAM-enabled 484 devices to selectively apply the mechanisms that use the flags 485 defined in this document to a subset of the traffic, and to limit the 486 performance of synthetically generated packets to a configurable 487 rate. Specifically, IOAM nodes should be able to: 489 o Limit the rate of IOAM packets with the Loopback flag (IOAM 490 encapsulating nodes), as discussed in Section 4.1.1. 492 o Limit the rate of looped back packets (IOAM transit and 493 decapsulating nodes), as discussed in Section 4.2. 495 o Limit the rate of IOAM packets with the Active flag (IOAM 496 encapsulating nodes), as discussed in Section 5. 498 As defined in Section 4, transit nodes that process a packet with the 499 Loopback flag only add a single data field, and truncate any payload 500 that follows the IOAM option(s), thus significanly limiting the 501 possible impact of an amplification attack. 503 9. Acknowledgments 505 The authors thank Martin Duke, Tommy Pauly, Greg Mirsky, and other 506 members of the IPPM working group for many helpful comments. 508 10. References 510 10.1. Normative References 512 [I-D.ietf-ippm-ioam-data] 513 Brockners, F., Bhandari, S., and T. Mizrahi, "Data Fields 514 for In-situ OAM", draft-ietf-ippm-ioam-data-15 (work in 515 progress), October 2021. 517 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 518 Requirement Levels", BCP 14, RFC 2119, 519 DOI 10.17487/RFC2119, March 1997, 520 . 522 [RFC5475] Zseby, T., Molina, M., Duffield, N., Niccolini, S., and F. 523 Raspall, "Sampling and Filtering Techniques for IP Packet 524 Selection", RFC 5475, DOI 10.17487/RFC5475, March 2009, 525 . 527 [RFC7014] D'Antonio, S., Zseby, T., Henke, C., and L. Peluso, "Flow 528 Selection Techniques", RFC 7014, DOI 10.17487/RFC7014, 529 September 2013, . 531 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 532 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 533 May 2017, . 535 10.2. Informative References 537 [I-D.ietf-ippm-ioam-ipv6-options] 538 Bhandari, S. and F. Brockners, "In-situ OAM IPv6 Options", 539 draft-ietf-ippm-ioam-ipv6-options-06 (work in progress), 540 July 2021. 542 [I-D.ietf-sfc-ioam-nsh] 543 Brockners, F. and S. Bhandari, "Network Service Header 544 (NSH) Encapsulation for In-situ OAM (IOAM) Data", draft- 545 ietf-sfc-ioam-nsh-06 (work in progress), July 2021. 547 [I-D.spiegel-ippm-ioam-rawexport] 548 Spiegel, M., Brockners, F., Bhandari, S., and R. 549 Sivakolundu, "In-situ OAM raw data export with IPFIX", 550 draft-spiegel-ippm-ioam-rawexport-05 (work in progress), 551 July 2021. 553 [RFC7799] Morton, A., "Active and Passive Metrics and Methods (with 554 Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799, 555 May 2016, . 557 Authors' Addresses 559 Tal Mizrahi 560 Huawei 561 Israel 563 Email: tal.mizrahi.phd@gmail.com 564 Frank Brockners 565 Cisco Systems, Inc. 566 Hansaallee 249, 3rd Floor 567 DUESSELDORF, NORDRHEIN-WESTFALEN 40549 568 Germany 570 Email: fbrockne@cisco.com 572 Shwetha Bhandari (editor) 573 Thoughtspot 574 3rd Floor, Indiqube Orion, 24th Main Rd, Garden Layout, HSR Layout 575 Bangalore, KARNATAKA 560 102 576 India 578 Email: shwetha.bhandari@thoughtspot.com 580 Ramesh Sivakolundu 581 Cisco Systems, Inc. 582 170 West Tasman Dr. 583 SAN JOSE, CA 95134 584 U.S.A. 586 Email: sramesh@cisco.com 588 Carlos Pignataro 589 Cisco Systems, Inc. 590 7200-11 Kit Creek Road 591 Research Triangle Park, NC 27709 592 United States 594 Email: cpignata@cisco.com 596 Aviv Kfir 597 Nvidia 599 Email: avivk@nvidia.com 600 Barak Gafni 601 Nvidia 602 350 Oakmead Parkway, Suite 100 603 Sunnyvale, CA 94085 604 U.S.A. 606 Email: gbarak@nvidia.com 608 Mickey Spiegel 609 Barefoot Networks, an Intel company 610 4750 Patrick Henry Drive 611 Santa Clara, CA 95054 612 US 614 Email: mickey.spiegel@intel.com 616 Jennifer Lemon 617 Broadcom 618 270 Innovation Drive 619 San Jose, CA 95134 620 US 622 Email: jennifer.lemon@broadcom.com