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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) No issues found here. Summary: 0 errors (**), 0 flaws (~~), 1 warning (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 SFC WG G. Mirsky 3 Internet-Draft ZTE Corp. 4 Updates: 8300 (if approved) W. Meng 5 Intended status: Standards Track ZTE Corporation 6 Expires: January 27, 2019 B. Khasnabish 7 ZTE TX, Inc. 8 C. Wang 9 July 26, 2018 11 Active OAM for Service Function Chains in Networks 12 draft-wang-sfc-multi-layer-oam-11 14 Abstract 16 A set of requirements for active Operation, Administration and 17 Maintenance (OAM) of Service Function Chains (SFCs) in networks is 18 presented. Based on these requirements an encapsulation of active 19 OAM message in SFC and a mechanism to detect and localize defects 20 described. Also, this document updates RFC 8300 in the definition of 21 O (OAM) bit in the Network Service Header (NSH) and defines how the 22 active OAM message identified in SFC NSH. 24 Status of This Memo 26 This Internet-Draft is submitted in full conformance with the 27 provisions of BCP 78 and BCP 79. 29 Internet-Drafts are working documents of the Internet Engineering 30 Task Force (IETF). Note that other groups may also distribute 31 working documents as Internet-Drafts. The list of current Internet- 32 Drafts is at https://datatracker.ietf.org/drafts/current/. 34 Internet-Drafts are draft documents valid for a maximum of six months 35 and may be updated, replaced, or obsoleted by other documents at any 36 time. It is inappropriate to use Internet-Drafts as reference 37 material or to cite them other than as "work in progress." 39 This Internet-Draft will expire on January 27, 2019. 41 Copyright Notice 43 Copyright (c) 2018 IETF Trust and the persons identified as the 44 document authors. All rights reserved. 46 This document is subject to BCP 78 and the IETF Trust's Legal 47 Provisions Relating to IETF Documents 48 (https://trustee.ietf.org/license-info) in effect on the date of 49 publication of this document. Please review these documents 50 carefully, as they describe your rights and restrictions with respect 51 to this document. Code Components extracted from this document must 52 include Simplified BSD License text as described in Section 4.e of 53 the Trust Legal Provisions and are provided without warranty as 54 described in the Simplified BSD License. 56 Table of Contents 58 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 59 2. Conventions . . . . . . . . . . . . . . . . . . . . . . . . . 3 60 2.1. Requirements Language . . . . . . . . . . . . . . . . . . 3 61 2.2. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 62 3. Requirements for Active OAM in SFC Network . . . . . . . . . 4 63 4. Active OAM Identification in SFC NSH . . . . . . . . . . . . 5 64 5. Echo Request/Echo Reply for SFC in Networks . . . . . . . . . 6 65 5.1. SFC Echo Request Transmission . . . . . . . . . . . . . . 8 66 5.2. SFC Echo Request Reception . . . . . . . . . . . . . . . 8 67 5.3. SFC Echo Reply Transmission . . . . . . . . . . . . . . . 8 68 5.4. Overlay Echo Reply Reception . . . . . . . . . . . . . . 9 69 6. Security Considerations . . . . . . . . . . . . . . . . . . . 9 70 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10 71 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 72 8.1. SFC Active OAM Protocol . . . . . . . . . . . . . . . . . 10 73 8.2. SFC Active OAM Message Type . . . . . . . . . . . . . . . 10 74 8.3. SFC Echo Request/Echo Reply Parameters . . . . . . . . . 11 75 8.4. SFC Echo Request/Echo Reply Message Types . . . . . . . . 11 76 8.5. SFC Echo Reply Modes . . . . . . . . . . . . . . . . . . 12 77 8.6. SFC TLV Type . . . . . . . . . . . . . . . . . . . . . . 12 78 8.7. SFC OAM UDP Port . . . . . . . . . . . . . . . . . . . . 13 79 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 13 80 9.1. Normative References . . . . . . . . . . . . . . . . . . 13 81 9.2. Informative References . . . . . . . . . . . . . . . . . 14 82 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15 84 1. Introduction 86 [RFC7665] defines components necessary to implement Service Function 87 Chain (SFC). These include a classifier which performs the 88 classification of incoming packets. A Service Function Forwarder 89 (SFF) is responsible for forwarding traffic to one or more connected 90 Service Functions (SFs) according to the information carried in the 91 SFC encapsulation. SFF also handles traffic coming back from the SF 92 and transports the data packets to the next SFF. And the SFF serves 93 as termination element of the Service Function Path (SFP). SF is 94 responsible for the specific treatment of received packets. 96 Resulting from that SFC is constructed by a number of these 97 components, there are different views from different levels of the 98 SFC. One is the SFC, entirely abstract entity, which defines an 99 ordered set of SFs that must be applied to packets selected as a 100 result of classification. But SFC doesn't specify the exact mapping 101 between SFFs and SFs. Thus there exists another semi-abstract entity 102 referred to as SFP. SFP is the instantiation of the SFC in the 103 network and provides a level of indirection between the entirely 104 abstract SFC and a fully specified ordered list of SFFs and SFs 105 identities that the packet will visit when it traverses the SFC. The 106 latter entity is being referred to as Rendered Service Path (RSP). 107 The main difference between SFP and RSP is that in the former the 108 authority to select the SFF/SF has been delegated to the network. 110 This document defines how active Operation, Administration and 111 Maintenance (OAM), per [RFC7799] definition of active OAM, identified 112 in Network Service Header (NSH) SFC, lists requirements to improve 113 the troubleshooting efficiency, and defines SFC Echo request and Echo 114 reply that enables on-demand Continuity Check, Connectivity 115 Verification among other operations over SFC in networks. Also, this 116 document updates Section 2.2 of [RFC8300] in part of the definition 117 of O bit in the (NSH). 119 2. Conventions 121 2.1. Requirements Language 123 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 124 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 125 "OPTIONAL" in this document are to be interpreted as described in BCP 126 14 [RFC2119] [RFC8174] when, and only when, they appear in all 127 capitals, as shown here. 129 2.2. Terminology 131 Unless explicitly specified in this document, active OAM in SFC and 132 SFC OAM are being used interchangeably. 134 e2e: End-to-End 136 FM: Fault Management 138 NSH: Network Service Header 140 OAM: Operations, Administration, and Maintenance 142 PRNG: Pseudorandom number generator 143 RDI: Remote Defect Indication 145 RSP: Rendered Service Path 147 SF: Service Function 149 SFC: Service Function Chain 151 SFF: Service Function Forwarder 153 SFP: Service Function Path 155 3. Requirements for Active OAM in SFC Network 157 To perform the OAM task of fault management (FM) in an SFC, that 158 includes failure detection, defect characterization and localization, 159 this document defines the set of requirements for active OAM 160 mechanisms to be used on an SFC. 162 +---+ +---+ +---+ +---+ +---+ +---+ 163 |SF1| |SF2| |SF3| |SF4| |SF5| |SF6| 164 +---+ +---+ +---+ +---+ +---+ +---+ 165 \ / \ / \ / 166 +----------+ +----+ +----+ +----+ 167 |Classifier|-------|SFF1|---------|SFF2|--------|SFF3| 168 +----------+ +----+ +----+ +----+ 170 Figure 1: SFC reference model 172 In the example presented in Figure 1, the service SFP1 may be 173 realized through two RSPs, RSP1(SF1--SF3--SF5) and RSP2(SF2--SF4-- 174 SF5). To perform end-to-end (e2e) FM SFC OAM: 176 REQ#1: Packets of active OAM in SFC SHOULD be fate sharing with 177 data traffic, i.e., in-band with the monitored traffic follow the 178 same RSP, in the forward direction from ingress toward egress 179 endpoint(s) of the OAM test. 181 REQ#2: SFC OAM MUST support pro-active monitoring of any element 182 in the SFC availability. 184 The egress, SFF3 in the example in Figure 1, is the entity that 185 detects the failure of the SFC. It must be able to signal the new 186 defect state to the ingress SFF1. Hence the following requirement: 188 REQ#3: SFC OAM MUST support Remote Defect Indication (RDI) 189 notification by the egress to the ingress. 191 REQ#4: SFC OAM MUST support connectivity verification. Definition 192 of the misconnection defect, entry and exit criteria are outside 193 the scope of this document. 195 Once the SFF1 detects the defect objective of OAM switches from 196 failure detection to defect characterization and localization. 198 REQ#5: SFC OAM MUST support fault localization of Loss of 199 Continuity check in the SFC. 201 REQ#6: SFC OAM MUST support tracing an SFP to realize the RSP. 203 It is practical, as presented in Figure 1, that several SFs share the 204 same SFF. In such case, SFP1 may be realized over two RSPs, 205 RSP1(SF1--SF3--SF5) and RSP2(SF2--SF4--SF6). 207 REQ#7: SFC OAM MUST have the ability to discover and exercise all 208 available RSPs in the transport network. 210 In the process of localizing the SFC failure, separating SFC OAM 211 layers is an efficient approach. To achieve that continuity among 212 SFFs that are part of the same SFP should be verified. Once SFFs 213 reachability along the particular SFP has been confirmed task of 214 defect localization may focus on SF reachability verification. 215 Because reachability of SFFs has already verified, SFF local to the 216 SF may be used as a source of the test packets. 218 REQ#8: SFC OAM MUST be able to trigger on-demand FM with responses 219 being directed towards initiator of such proxy request. 221 4. Active OAM Identification in SFC NSH 223 The interpretation of O bit flag in the NSH header is defined in 224 [RFC8300] as: 226 O bit: Setting this bit indicates an OAM packet. 228 This document updates the definition of O bit as follows: 230 O bit: Setting this bit indicates an OAM command and/or data in 231 the NSH Context Header 233 Also, active SFC OAM defined as OAM commands and/or data included in 234 a message that immediately follows the NSH. To identify the active 235 OAM message the value on the Next Protocol field MUST be set to OAM 236 (TBA1) according to Section 8.1. 238 Several active OAM protocols will be needed to address all the 239 requirements listed in Section 3. Destination UDP port number may 240 identify protocols if IP/UDP encapsulation used. But extra IP/UDP 241 headers, especially in the case of IPv6, add noticeable overhead. 242 This document defines Active OAM Header Figure 2 to demultiplex 243 active OAM protocols on an SFC. 245 0 1 2 3 246 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 1 247 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 248 | V | Msg Type | Flags | Length | 249 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 250 ~ SFC Active OAM Control Packet ~ 251 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 253 Figure 2: SFC Active OAM Header 255 V - two bits long field indicates the current version of the SFC 256 active OAM header. The current value is 0. 258 Msg Type - six bits long field identifies OAM protocol, e.g., Echo 259 Request/Reply or BFD. 261 Flags - eight bits long field carries bit flags that define 262 optional capability and thus processing of the SFC active OAM 263 control packet, e.g., optional timestamping. 265 Length - two octets long field that is the length of the SFC 266 active OAM control packet in octets. 268 5. Echo Request/Echo Reply for SFC in Networks 270 Echo Request/Reply is a well-known active OAM mechanism that is 271 extensively used to detect inconsistencies between a state in control 272 and the data planes, localize defects in the data plane. The format 273 of the Echo request/Echo reply control packet is to support ping and 274 traceroute functionality in SFC in networks Figure 3 resembles the 275 format of MPLS LSP Ping [RFC8029] with some exceptions. 277 0 1 2 3 278 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 1 279 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 280 | Version Number | Global Flags | 281 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 282 | Message Type | Reply mode | Return Code | Return S.code | 283 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 284 | Sender's Handle | 285 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 286 | Sequence Number | 287 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 288 ~ TLVs ~ 289 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 291 Figure 3: SFC Echo Request/Reply format 293 The interpretation of the fields is as follows: 295 The Version reflects the current version. The version number is 296 to be incremented whenever a change is made that affects the 297 ability of an implementation to parse or process control packet 298 correctly. 300 The Global Flags is a bit vector field. 302 The Message Type filed reflects the type of the packet. Value 303 TBA3 identifies echo request and TBA4 - echo reply 305 The Reply Mode defines the type of the return path requested by 306 the sender of the echo request. 308 Return Codes and Subcodes can be used to inform the sender about 309 the result of processing its request. 311 The Sender's Handle is filled in by the sender and returned 312 unchanged by the receiver in the echo reply. The sender MAY use a 313 pseudo-random number generator (PRNG) to set the value of the 314 Sender's Handle field. The value of the Sender's Handle field 315 SHOULD NOT be changed in the course of the test session. 317 The Sequence Number is assigned by the sender and can be (for 318 example) used to detect missed replies. The value of the Sequence 319 Number field SHOULD be monotonically increasing in the course of 320 the test session. 322 TLVs (Type-Length-Value tuples) have the two octets long Type 323 field, two octets long Length field that is the length of the 324 Value field in octets. 326 5.1. SFC Echo Request Transmission 328 SFC echo request control packet MUST use the appropriate 329 encapsulation of the monitored SFP. If Network Service Header (NSH) 330 is used, echo request MUST set O bit, as defined in [RFC8300]. SFC 331 NSH MUST be immediately followed by the SFC Active OAM Header defined 332 in Section 4. Message Type field in the SFC Active OAM Header MUST 333 be set to SFC Echo Request/Echo Reply value (TBA2) per Section 8.2. 335 Value of the Reply Mode field MAY be set to: 337 o Do Not Reply (TBA5) if one-way monitoring is desired. If the echo 338 request is used to measure synthetic packet loss; the receiver may 339 report loss measurement results to a remote node. 341 o Reply via an IPv4/IPv6 UDP Packet (TBA6) value likely will be the 342 most used. 344 o Reply via Application Level Control Channel (TBA7) value if the 345 SFP may have bi-directional paths. 347 o Reply via Specified Path (TBA7) value to enforce the use of the 348 particular return path specified in the included TLV to verify bi- 349 directional continuity and also increase the robustness of the 350 monitoring by selecting a more stable path. 352 5.2. SFC Echo Request Reception 354 5.3. SFC Echo Reply Transmission 356 The Reply Mode field directs whether and how the echo reply message 357 should be sent. The sender of the echo request MAY use TLVs to 358 request that corresponding echo reply is transmitted over the 359 specified path. Value TBA3 is referred to as "Do not reply" mode and 360 suppresses transmission of echo reply packet. The default value 361 (TBA6) for the Reply mode field requests the responder to send the 362 echo reply packet out-of-band as IPv4 or IPv6 UDP packet. 364 Responder to the SFC echo request sends the echo reply over IP 365 network if the Reply mode is Reply via an IPv4/IPv6 UDP Packet. 366 Because SFC NSH does not identify the ingress of the SFP the echo 367 request the source ID MUST be included in the message and used as the 368 IP destination address for IP/UDP encapsulation of the SFC echo 369 reply. The sender of the SFC echo request MUST include SFC Source 370 TLV Figure 4. 372 0 1 2 3 373 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 1 374 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 375 | SFC OAM Source ID Type | Length | 376 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 377 | Value | 378 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 380 Figure 4: SFC Source TLV 382 where 384 SFC OAM Source Id Type is two octets in length and has the value 385 of TBA9 Section 8.6. 387 Length is two octets long field, and the value equals the length 388 of the Value field in octets. 390 Value field contains the IP address of the sender of the SFC OAM 391 control message, IPv4 or IPv6. 393 The UDP destination port for SFC Echo Reply TBA10 will be allocated 394 by IANA Section 8.7. 396 5.4. Overlay Echo Reply Reception 398 6. Security Considerations 400 Overlay Echo Request/Reply operates within the domain of the overlay 401 network and thus inherits any security considerations that apply to 402 the use of that overlay technology and, consequently, underlay data 403 plane. Also, the security needs for SFC echo request/reply are 404 similar to those of ICMP ping [RFC0792], [RFC4443] and MPLS LSP ping 405 [RFC8029]. 407 There are at least three approaches of attacking a node in the 408 overlay network using the mechanisms defined in the document. One is 409 a Denial-of-Service attack, by sending SFC ping to overload an 410 element of the SFC. The second may use spoofing, hijacking, 411 replying, or otherwise tampering with SFC echo requests and/or 412 replies to misrepresent, alter operator's view of the state of the 413 SFC. The third is an unauthorized source using an SFC echo request/ 414 reply to obtain information about the SFC and/or its elements, e.g. 415 SFF or SF. 417 It is RECOMMENDED that implementations throttle the SFC ping traffic 418 going to the control plane to mitigate potential Denial-of-Service 419 attacks. 421 Reply and spoofing attacks involving faking or replying SFC echo 422 reply messages would have to match the Sender's Handle and Sequence 423 Number of an outstanding SFC echo request message which is highly 424 unlikely. Thus the non-matching reply would be discarded. 426 To protect against unauthorized sources trying to obtain information 427 about the overlay and/or underlay an implementation MAY check that 428 the source of the echo request is indeed part of the SFP. 430 7. Acknowledgments 432 Authors greatly appreciate thorough review and the most helpful 433 comments from Dan Wing. 435 8. IANA Considerations 437 8.1. SFC Active OAM Protocol 439 IANA is requested to assign a new type from the SFC Next Protocol 440 registry as follows: 442 +-------+----------------+---------------+ 443 | Value | Description | Reference | 444 +-------+----------------+---------------+ 445 | TBA1 | SFC Active OAM | This document | 446 +-------+----------------+---------------+ 448 Table 1: SFC Active OAM Protocol 450 8.2. SFC Active OAM Message Type 452 IANA is requested to create a new registry called "SFC Active OAM 453 Message Type". All code points in the range 1 through 32767 in this 454 registry shall be allocated according to the "IETF Review" procedure 455 as specified in [RFC8126]. Remaining code points to be allocated 456 according to the table Table 2: 458 +---------------+-------------+-------------------------+ 459 | Value | Description | Reference | 460 +---------------+-------------+-------------------------+ 461 | 0 | Reserved | | 462 | 1 - 32767 | Reserved | IETF Consensus | 463 | 32768 - 65530 | Reserved | First Come First Served | 464 | 65531 - 65534 | Reserved | Private Use | 465 | 65535 | Reserved | | 466 +---------------+-------------+-------------------------+ 468 Table 2: SFC Active OAM Message Type 470 IANA is requested to assign new type from the SFC Active OAM Message 471 Type registry as follows: 473 +-------+-----------------------------+---------------+ 474 | Value | Description | Reference | 475 +-------+-----------------------------+---------------+ 476 | TBA2 | SFC Echo Request/Echo Reply | This document | 477 +-------+-----------------------------+---------------+ 479 Table 3: SFC Echo Request/Echo Reply Type 481 8.3. SFC Echo Request/Echo Reply Parameters 483 IANA is requested to create new SFC Echo Request/Echo Reply 484 Parameters registry. 486 8.4. SFC Echo Request/Echo Reply Message Types 488 IANA is requested to create in the SFC Echo Request/Echo Reply 489 Parameters registry the new sub-registry Message Types. All code 490 points in the range 1 through 191 in this registry shall be allocated 491 according to the "IETF Review" procedure as specified in [RFC8126] 492 and assign values as follows: 494 +------------+------------------+-------------------------+ 495 | Value | Description | Reference | 496 +------------+------------------+-------------------------+ 497 | 0 | Reserved | | 498 | TBA3 | SFC Echo Request | This document | 499 | TBA4 | SFC Echo Reply | This document | 500 | TBA4+1-191 | Unassigned | IETF Review | 501 | 192-251 | Unassigned | First Come First Served | 502 | 252-254 | Unassigned | Private Use | 503 | 255 | Reserved | | 504 +------------+------------------+-------------------------+ 506 Table 4: SFC Echo Request/Echo Reply Message Types 508 8.5. SFC Echo Reply Modes 510 IANA is requested to create in the SFC Echo Request/Echo Reply 511 Parameters registry the new sub-registry Reply Modes All code points 512 in the range 1 through 191 in this registry shall be allocated 513 according to the "IETF Review" procedure as specified in [RFC8126] 514 and assign values as follows: 516 +------------+---------------------------------+--------------------+ 517 | Value | Description | Reference | 518 +------------+---------------------------------+--------------------+ 519 | 0 | Reserved | | 520 | TBA5 | Do Not Reply | This document | 521 | TBA6 | Reply via an IPv4/IPv6 UDP | This document | 522 | | Packet | | 523 | TBA7 | Reply via Application Level | This document | 524 | | Control Channel | | 525 | TBA8 | Reply via Specified Path | This document | 526 | TBA8+1-191 | Unassigned | IETF Review | 527 | 192-251 | Unassigned | First Come First | 528 | | | Served | 529 | 252-254 | Unassigned | Private Use | 530 | 255 | Reserved | | 531 +------------+---------------------------------+--------------------+ 533 Table 5: SFC Echo Reply Modes 535 8.6. SFC TLV Type 537 IANA is requested to create SFC OAM TLV Type registry. All code 538 points in the range 1 through 32759 in this registry shall be 539 allocated according to the "IETF Review" procedure as specified in 540 [RFC8126]. Code points in the range 32760 through 65279 in this 541 registry shall be allocated according to the "First Come First 542 Served" procedure as specified in [RFC8126]. Remaining code points 543 are allocated according to the Table 6: 545 +---------------+--------------+-------------------------+ 546 | Value | Description | Reference | 547 +---------------+--------------+-------------------------+ 548 | 0 | Reserved | This document | 549 | 1- 32759 | Unassigned | IETF Review | 550 | 32760 - 65279 | Unassigned | First Come First Served | 551 | 65280 - 65519 | Experimental | This document | 552 | 65520 - 65534 | Private Use | This document | 553 | 65535 | Reserved | This document | 554 +---------------+--------------+-------------------------+ 556 Table 6: SFC TLV Type Registry 558 This document defines the following new value in SFC OAM TLV Type 559 registry: 561 +-------+-------------------+---------------+ 562 | Value | Description | Reference | 563 +-------+-------------------+---------------+ 564 | TBA9 | Source IP Address | This document | 565 +-------+-------------------+---------------+ 567 Table 7: SFC OAM Source IP Address Type 569 8.7. SFC OAM UDP Port 571 IANA is requested to allocate UDP port number according to 573 +---------+--------+------------+---------+--------------+----------+ 574 | Service | Port | Transport | Descrip | Semantics | Referenc | 575 | Name | Number | Protocol | tion | Definition | e | 576 +---------+--------+------------+---------+--------------+----------+ 577 | SFC OAM | TBA10 | UDP | SFC OAM | Section 5.3 | This | 578 | | | | | | document | 579 +---------+--------+------------+---------+--------------+----------+ 581 Table 8: SFC OAM Port 583 9. References 585 9.1. Normative References 587 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 588 Requirement Levels", BCP 14, RFC 2119, 589 DOI 10.17487/RFC2119, March 1997, 590 . 592 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 593 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 594 May 2017, . 596 [RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed., 597 "Network Service Header (NSH)", RFC 8300, 598 DOI 10.17487/RFC8300, January 2018, 599 . 601 9.2. Informative References 603 [RFC0792] Postel, J., "Internet Control Message Protocol", STD 5, 604 RFC 792, DOI 10.17487/RFC0792, September 1981, 605 . 607 [RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet 608 Control Message Protocol (ICMPv6) for the Internet 609 Protocol Version 6 (IPv6) Specification", STD 89, 610 RFC 4443, DOI 10.17487/RFC4443, March 2006, 611 . 613 [RFC7665] Halpern, J., Ed. and C. Pignataro, Ed., "Service Function 614 Chaining (SFC) Architecture", RFC 7665, 615 DOI 10.17487/RFC7665, October 2015, 616 . 618 [RFC7799] Morton, A., "Active and Passive Metrics and Methods (with 619 Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799, 620 May 2016, . 622 [RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N., 623 Aldrin, S., and M. Chen, "Detecting Multiprotocol Label 624 Switched (MPLS) Data-Plane Failures", RFC 8029, 625 DOI 10.17487/RFC8029, March 2017, 626 . 628 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for 629 Writing an IANA Considerations Section in RFCs", BCP 26, 630 RFC 8126, DOI 10.17487/RFC8126, June 2017, 631 . 633 Authors' Addresses 635 Greg Mirsky 636 ZTE Corp. 638 Email: gregimirsky@gmail.com 640 Wei Meng 641 ZTE Corporation 642 No.50 Software Avenue, Yuhuatai District 643 Nanjing 644 China 646 Email: meng.wei2@zte.com.cn,vally.meng@gmail.com 648 Bhumip Khasnabish 649 ZTE TX, Inc. 650 55 Madison Avenue, Suite 160 651 Morristown, New Jersey 07960 652 USA 654 Email: bhumip.khasnabish@ztetx.com 656 Cui Wang 658 Email: lindawangjoy@gmail.com