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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: September 9, 2019 B. Khasnabish 7 Individual contributor 8 C. Wang 9 March 8, 2019 11 Active OAM for Service Function Chains in Networks 12 draft-ietf-sfc-multi-layer-oam-02 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 September 9, 2019. 41 Copyright Notice 43 Copyright (c) 2019 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 . . . . . . . . . 7 65 5.1. Return Codes . . . . . . . . . . . . . . . . . . . . . . 8 66 5.2. SFC Echo Request Transmission . . . . . . . . . . . . . . 9 67 5.3. SFC Echo Request Reception . . . . . . . . . . . . . . . 9 68 5.4. SFC Echo Reply Transmission . . . . . . . . . . . . . . . 10 69 5.5. SFC Echo Reply Reception . . . . . . . . . . . . . . . . 10 70 6. Security Considerations . . . . . . . . . . . . . . . . . . . 11 71 7. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 12 72 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 73 8.1. SFC Active OAM Protocol . . . . . . . . . . . . . . . . . 12 74 8.2. SFC Active OAM Message Type . . . . . . . . . . . . . . . 12 75 8.3. SFC Echo Request/Echo Reply Parameters . . . . . . . . . 13 76 8.4. SFC Echo Request/Echo Reply Message Types . . . . . . . . 13 77 8.5. SFC Echo Reply Modes . . . . . . . . . . . . . . . . . . 13 78 8.6. SFC Echo Return Codes . . . . . . . . . . . . . . . . . . 14 79 8.7. SFC TLV Type . . . . . . . . . . . . . . . . . . . . . . 14 80 8.8. SFC OAM UDP Port . . . . . . . . . . . . . . . . . . . . 15 81 9. References . . . . . . . . . . . . . . . . . . . . . . . . . 16 82 9.1. Normative References . . . . . . . . . . . . . . . . . . 16 83 9.2. Informative References . . . . . . . . . . . . . . . . . 16 84 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 17 86 1. Introduction 88 [RFC7665] defines components necessary to implement Service Function 89 Chain (SFC). These include a classifier which performs the 90 classification of incoming packets. A Service Function Forwarder 91 (SFF) is responsible for forwarding traffic to one or more connected 92 Service Functions (SFs) according to the information carried in the 93 SFC encapsulation. SFF also handles traffic coming back from the SF 94 and transports the data packets to the next SFF. And the SFF serves 95 as termination element of the Service Function Path (SFP). SF is 96 responsible for the specific treatment of received packets. 98 Resulting from that SFC is constructed by a number of these 99 components, there are different views from different levels of the 100 SFC. One is the SFC, entirely abstract entity, which defines an 101 ordered set of SFs that must be applied to packets selected as a 102 result of classification. But SFC doesn't specify the exact mapping 103 between SFFs and SFs. Thus there exists another semi-abstract entity 104 referred to as SFP. SFP is the instantiation of the SFC in the 105 network and provides a level of indirection between the entirely 106 abstract SFC and a fully specified ordered list of SFFs and SFs 107 identities that the packet will visit when it traverses the SFC. The 108 latter entity is being referred to as Rendered Service Path (RSP). 109 The main difference between SFP and RSP is that in the former the 110 authority to select the SFF/SF has been delegated to the network. 112 This document defines how active Operation, Administration and 113 Maintenance (OAM), per [RFC7799] definition of active OAM, identified 114 in Network Service Header (NSH) SFC, lists requirements to improve 115 the troubleshooting efficiency, and defines SFC Echo request and Echo 116 reply that enables on-demand Continuity Check, Connectivity 117 Verification among other operations over SFC in networks. Also, this 118 document updates Section 2.2 of [RFC8300] in part of the definition 119 of O bit in the (NSH). 121 2. Conventions 123 2.1. Requirements Language 125 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 126 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 127 "OPTIONAL" in this document are to be interpreted as described in BCP 128 14 [RFC2119] [RFC8174] when, and only when, they appear in all 129 capitals, as shown here. 131 2.2. Terminology 133 Unless explicitly specified in this document, active OAM in SFC and 134 SFC OAM are being used interchangeably. 136 e2e: End-to-End 138 FM: Fault Management 140 NSH: Network Service Header 142 OAM: Operations, Administration, and Maintenance 144 PRNG: Pseudorandom number generator 145 RDI: Remote Defect Indication 147 RSP: Rendered Service Path 149 SMI Structure of Management Information 151 SF: Service Function 153 SFC: Service Function Chain 155 SFF: Service Function Forwarder 157 SFP: Service Function Path 159 3. Requirements for Active OAM in SFC Network 161 To perform the OAM task of fault management (FM) in an SFC, that 162 includes failure detection, defect characterization and localization, 163 this document defines the set of requirements for active OAM 164 mechanisms to be used on an SFC. 166 +---+ +---+ +---+ +---+ +---+ +---+ 167 |SF1| |SF2| |SF3| |SF4| |SF5| |SF6| 168 +---+ +---+ +---+ +---+ +---+ +---+ 169 \ / \ / \ / 170 +----------+ +----+ +----+ +----+ 171 |Classifier|-------|SFF1|---------|SFF2|--------|SFF3| 172 +----------+ +----+ +----+ +----+ 174 Figure 1: SFC reference model 176 In the example presented in Figure 1, the service SFP1 may be 177 realized through two independent RSPs, RSP1(SF1--SF3--SF5) and 178 RSP2(SF2--SF4--SF5). To perform end-to-end (e2e) FM SFC OAM: 180 REQ#1: Packets of active OAM in SFC SHOULD be fate sharing with 181 data traffic, i.e., in-band with the monitored traffic follow the 182 same RSP, in the forward direction from ingress toward egress 183 endpoint(s) of the OAM test. 185 REQ#2: SFC OAM MUST support pro-active monitoring of any element 186 in the SFC availability. 188 The egress, SFF3 in the example in Figure 1, is the entity that 189 detects the failure of the SFC. It must be able to signal the new 190 defect state to the ingress SFF1. Hence the following requirement: 192 REQ#3: SFC OAM MUST support Remote Defect Indication (RDI) 193 notification by the egress to the ingress. 195 REQ#4: SFC OAM MUST support connectivity verification. Definition 196 of the misconnection defect, entry and exit criteria are outside 197 the scope of this document. 199 Once the SFF1 detects the defect objective of OAM switches from 200 failure detection to defect characterization and localization. 202 REQ#5: SFC OAM MUST support fault localization of Loss of 203 Continuity check in the SFC. 205 REQ#6: SFC OAM MUST support tracing an SFP to realize the RSP. 207 It is practical, as presented in Figure 1, that several SFs share the 208 same SFF. In such case, SFP1 may be realized over two RSPs, 209 RSP1(SF1--SF3--SF5) and RSP2(SF2--SF4--SF6). 211 REQ#7: SFC OAM MUST have the ability to discover and exercise all 212 available RSPs in the transport network. 214 In the process of localizing the SFC failure, separating SFC OAM 215 layers is an efficient approach. To achieve that continuity among 216 SFFs that are part of the same SFP should be verified. Once SFFs 217 reachability along the particular SFP has been confirmed task of 218 defect localization may focus on SF reachability verification. 219 Because reachability of SFFs has already verified, SFF local to the 220 SF may be used as a source of the test packets. 222 REQ#8: SFC OAM MUST be able to trigger on-demand FM with responses 223 being directed towards initiator of such proxy request. 225 4. Active OAM Identification in SFC NSH 227 The interpretation of O bit flag in the NSH header is defined in 228 [RFC8300] as: 230 O bit: Setting this bit indicates an OAM packet. 232 This document updates the definition of O bit as follows: 234 O bit: Setting this bit indicates an OAM command and/or data in 235 the NSH Context Header or packet payload 237 Active SFC OAM defined as a combination of OAM commands and/or data 238 included in a message that immediately follows the NSH. To identify 239 the active OAM message the value on the Next Protocol field MUST be 240 set to Active SFC OAM (TBA1) according to Section 8.1. The rules of 241 interpreting the values of O bit and the Next Protocol field are as 242 follows: 244 o O bit set, and the Next Protocol value is not one of identifying 245 active or hybrid OAM protocol (per [RFC7799] definitions), e.g., 246 defined in this specification Active SFC OAM - a Fixed-Length 247 Context Header or Variable-Length Context Header(s) contain OAM 248 command or data. and the type of payload determined by the Next 249 Protocol field; 251 o O bit set, and the Next Protocol value is one of identifying 252 active or hybrid OAM protocol - the payload that immediately 253 follows SFC NSH contains OAM command or data; 255 o O bit is clear - no OAM in a Fixed-Length Context Header or 256 Variable-Length Context Header(s) and the payload determined by 257 the value of the Next Protocol field; 259 o O bit is clear and the Next Protocol value is one of identifying 260 active or hybrid OAM protocol MUST be identified and reported as 261 the erroneous combination. An implementation MAY have control to 262 enable processing of the OAM payload. 264 From the above-listed rules follows the recommendation to avoid 265 combination of OAM in a Fixed-Length Context Header or Variable- 266 Length Context Header(s) and in the payload immediately following the 267 SFC NSH because there is no unambiguous way to identify such 268 combination using the O bit and the Next Protocol field. 270 Several active OAM protocols will be needed to address all the 271 requirements listed in Section 3. Destination UDP port number may 272 identify protocols if IP/UDP encapsulation used. But extra IP/UDP 273 headers, especially in the case of IPv6, add noticeable overhead. 274 This document defines Active OAM Header Figure 2 to demultiplex 275 active OAM protocols on an SFC. 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 | V | Msg Type | Flags | Length | 281 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 282 ~ SFC Active OAM Control Packet ~ 283 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 285 Figure 2: SFC Active OAM Header 287 V - two bits long field indicates the current version of the SFC 288 active OAM header. The current value is 0. 290 Msg Type - six bits long field identifies OAM protocol, e.g., Echo 291 Request/Reply or Bidirectional Forwarding Detection. 293 Flags - eight bits long field carries bit flags that define 294 optional capability and thus processing of the SFC active OAM 295 control packet, e.g., optional timestamping. 297 Length - two octets long field that is the length of the SFC 298 active OAM control packet in octets. 300 5. Echo Request/Echo Reply for SFC in Networks 302 Echo Request/Reply is a well-known active OAM mechanism that is 303 extensively used to detect inconsistencies between a state in control 304 and the data planes, localize defects in the data plane. The format 305 of the Echo request/Echo reply control packet is to support ping and 306 traceroute functionality in SFC in networks Figure 3 resembles the 307 format of MPLS LSP Ping [RFC8029] with some exceptions. 309 0 1 2 3 310 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 1 311 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 312 | Version Number | Global Flags | 313 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 314 | Message Type | Reply mode | Return Code | Return S.code | 315 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 316 | Sender's Handle | 317 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 318 | Sequence Number | 319 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 320 ~ TLVs ~ 321 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 323 Figure 3: SFC Echo Request/Reply format 325 The interpretation of the fields is as follows: 327 The Version reflects the current version. The version number is 328 to be incremented whenever a change is made that affects the 329 ability of an implementation to parse or process control packet 330 correctly. 332 The Global Flags is a bit vector field. 334 The Message Type filed reflects the type of the packet. Value 335 TBA3 identifies echo request and TBA4 - echo reply 337 The Reply Mode defines the type of the return path requested by 338 the sender of the echo request. 340 Return Codes and Subcodes can be used to inform the sender about 341 the result of processing its request. 343 The Sender's Handle is filled in by the sender and returned 344 unchanged by the receiver in the echo reply. The sender MAY use a 345 pseudo-random number generator (PRNG) to set the value of the 346 Sender's Handle field. The value of the Sender's Handle field 347 SHOULD NOT be changed in the course of the test session. 349 The Sequence Number is assigned by the sender and can be (for 350 example) used to detect missed replies. The value of the Sequence 351 Number field SHOULD be monotonically increasing in the course of 352 the test session. 354 TLVs (Type-Length-Value tuples) have the two octets long Type 355 field, two octets long Length field that is the length of the 356 Value field in octets. Type values, see Section 8.7, less than 357 32768 identify mandatory TLVs that MUST either be supported by an 358 implementation or result in the Return Code of 2 ("One or more of 359 the TLVs was not understood") being sent in the echo response. 360 Type values greater than or equal to 32768 identify optional TLVs 361 that SHOULD be ignored if the implementation does not understand 362 or support them. If a Type value for TLV or sub-TLV is in the 363 range for Vendor Private Use, the Length MUST be at least 4, and 364 the first four octets MUST be that vendor's the Structure of 365 Management Information (SMI) [RFC1423] Private Enterprise Number, 366 in network octet order. The rest of the Value field is private to 367 the vendor. 369 5.1. Return Codes 371 The Return Code is set to zero by the sender of an echo request. The 372 receiver of said echo request can set it to one of the values listed 373 below in the corresponding echo reply that it generates. 375 Value Meaning 376 ----- ------- 377 0 No Return Code 378 1 Malformed echo request received 379 2 One or more of the TLVs was not understood 381 5.2. SFC Echo Request Transmission 383 SFC echo request control packet MUST use the appropriate 384 encapsulation of the monitored SFP. If Network Service Header (NSH) 385 is used, echo request MUST set O bit, as defined in [RFC8300]. SFC 386 NSH MUST be immediately followed by the SFC Active OAM Header defined 387 in Section 4. Message Type field in the SFC Active OAM Header MUST 388 be set to SFC Echo Request/Echo Reply value (TBA2) per Section 8.2. 390 Value of the Reply Mode field MAY be set to: 392 o Do Not Reply (TBA5) if one-way monitoring is desired. If the echo 393 request is used to measure synthetic packet loss; the receiver may 394 report loss measurement results to a remote node. 396 o Reply via an IPv4/IPv6 UDP Packet (TBA6) value likely will be the 397 most used. 399 o Reply via Application Level Control Channel (TBA7) value if the 400 SFP may have bi-directional paths. 402 o Reply via Specified Path (TBA8) value to enforce the use of the 403 particular return path specified in the included TLV to verify bi- 404 directional continuity and also increase the robustness of the 405 monitoring by selecting a more stable path. 407 5.3. SFC Echo Request Reception 409 Sending an SFC echo request to the control plane is triggered by one 410 of the following packet processing exceptions: NSH TTL expiration, 411 NSH Service Index (SI) expiration or the receiver is the terminal SFF 412 for an SFP. 414 Firstly, the SFF that has received an SFC echo request verifies the 415 general sanity of the received packet. If the packet is not well- 416 formed, the receiver SFF SHOULD send an SFC echo reply with the 417 Return Code set to "Malformed echo request received" and the Subcode 418 set to zero. If there are any TLVs not marked as "Ignore" (i.e., if 419 the TLV type is less than 32768, see Section 3) that SFF does not 420 understand, the SFF SHOULD send an SFC echo reply with the Return 421 Code set to "TLV not understood" and set the Subcode to zero. In the 422 latter case, the SFF SHOULD include an Errored TLVs TLV that as sub- 423 TLVs contains only the misunderstood TLVs. The header field's 424 Sender's Handle, Sequence Number are not examined but are included in 425 the SFC echo reply message. 427 5.4. SFC Echo Reply Transmission 429 The Reply Mode field directs whether and how the echo reply message 430 should be sent. The sender of the echo request MAY use TLVs to 431 request that the corresponding echo reply is transmitted over the 432 specified path. Value TBA3 is referred to as "Do not reply" mode and 433 suppresses transmission of echo reply packet. The default value 434 (TBA6) for the Reply mode field requests the responder to send the 435 echo reply packet out-of-band as IPv4 or IPv6 UDP packet. 437 Responder to the SFC echo request sends the echo reply over IP 438 network if the Reply mode is Reply via an IPv4/IPv6 UDP Packet. 439 Because SFC NSH does not identify the ingress of the SFP the echo 440 request, the source ID MUST be included in the message and used as 441 the IP destination address for IP/UDP encapsulation of the SFC echo 442 reply. The sender of the SFC echo request MUST include SFC Source 443 TLV Figure 4. 445 0 1 2 3 446 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 1 447 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 448 | SFC OAM Source ID Type | Length | 449 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 450 | Value | 451 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 453 Figure 4: SFC Source TLV 455 where 457 SFC OAM Source Id Type is two octets in length and has the value 458 of TBA9 Section 8.7. 460 Length is two octets long field, and the value equals the length 461 of the Value field in octets. 463 Value field contains the IP address of the sender of the SFC OAM 464 control message, IPv4 or IPv6. 466 The UDP destination port for SFC Echo Reply TBA10 will be allocated 467 by IANA Section 8.8. 469 5.5. SFC Echo Reply Reception 471 An SFF SHOULD NOT accept SFC echo reply unless the received passes 472 the following checks: 474 o the received SFC echo reply is well-formed; 476 o it has outstanding SFC echo request sent from the UDP port that 477 matches destination UDP port number of the received packet; 479 o if the matching to the echo request found, the value of Sender's 480 Handle n the echo request sent is equal to the value of Sender's 481 Handle in the echo reply received; 483 o if all checks passed, the SFF checks if the Sequence Number in the 484 echo request sent matches to the Sequence Number in the echo reply 485 received. 487 6. Security Considerations 489 Overlay Echo Request/Reply operates within the domain of the overlay 490 network and thus inherits any security considerations that apply to 491 the use of that overlay technology and, consequently, underlay data 492 plane. Also, the security needs for SFC echo request/reply are 493 similar to those of ICMP ping [RFC0792], [RFC4443] and MPLS LSP ping 494 [RFC8029]. 496 There are at least three approaches of attacking a node in the 497 overlay network using the mechanisms defined in the document. One is 498 a Denial-of-Service attack, by sending SFC ping to overload an 499 element of the SFC. The second may use spoofing, hijacking, 500 replying, or otherwise tampering with SFC echo requests and/or 501 replies to misrepresent, alter operator's view of the state of the 502 SFC. The third is an unauthorized source using an SFC echo request/ 503 reply to obtain information about the SFC and/or its elements, e.g. 504 SFF or SF. 506 It is RECOMMENDED that implementations throttle the SFC ping traffic 507 going to the control plane to mitigate potential Denial-of-Service 508 attacks. 510 Reply and spoofing attacks involving faking or replying SFC echo 511 reply messages would have to match the Sender's Handle and Sequence 512 Number of an outstanding SFC echo request message which is highly 513 unlikely. Thus the non-matching reply would be discarded. 515 To protect against unauthorized sources trying to obtain information 516 about the overlay and/or underlay an implementation MAY check that 517 the source of the echo request is indeed part of the SFP. 519 7. Acknowledgments 521 Authors greatly appreciate thorough review and the most helpful 522 comments from Dan Wing and Dirk von Hugo. 524 8. IANA Considerations 526 8.1. SFC Active OAM Protocol 528 IANA is requested to assign a new type from the SFC Next Protocol 529 registry as follows: 531 +-------+----------------+---------------+ 532 | Value | Description | Reference | 533 +-------+----------------+---------------+ 534 | TBA1 | SFC Active OAM | This document | 535 +-------+----------------+---------------+ 537 Table 1: SFC Active OAM Protocol 539 8.2. SFC Active OAM Message Type 541 IANA is requested to create a new registry called "SFC Active OAM 542 Message Type". All code points in the range 1 through 32767 in this 543 registry shall be allocated according to the "IETF Review" procedure 544 as specified in [RFC8126]. Remaining code points to be allocated 545 according to the table Table 2: 547 +---------------+-------------+-------------------------+ 548 | Value | Description | Reference | 549 +---------------+-------------+-------------------------+ 550 | 0 | Reserved | | 551 | 1 - 32767 | Reserved | IETF Consensus | 552 | 32768 - 65530 | Reserved | First Come First Served | 553 | 65531 - 65534 | Reserved | Private Use | 554 | 65535 | Reserved | | 555 +---------------+-------------+-------------------------+ 557 Table 2: SFC Active OAM Message Type 559 IANA is requested to assign new type from the SFC Active OAM Message 560 Type registry as follows: 562 +-------+-----------------------------+---------------+ 563 | Value | Description | Reference | 564 +-------+-----------------------------+---------------+ 565 | TBA2 | SFC Echo Request/Echo Reply | This document | 566 +-------+-----------------------------+---------------+ 568 Table 3: SFC Echo Request/Echo Reply Type 570 8.3. SFC Echo Request/Echo Reply Parameters 572 IANA is requested to create new SFC Echo Request/Echo Reply 573 Parameters registry. 575 8.4. SFC Echo Request/Echo Reply Message Types 577 IANA is requested to create in the SFC Echo Request/Echo Reply 578 Parameters registry the new sub-registry Message Types. All code 579 points in the range 1 through 191 in this registry shall be allocated 580 according to the "IETF Review" procedure as specified in [RFC8126] 581 and assign values as follows: 583 +------------+------------------+-------------------------+ 584 | Value | Description | Reference | 585 +------------+------------------+-------------------------+ 586 | 0 | Reserved | | 587 | TBA3 | SFC Echo Request | This document | 588 | TBA4 | SFC Echo Reply | This document | 589 | TBA4+1-191 | Unassigned | IETF Review | 590 | 192-251 | Unassigned | First Come First Served | 591 | 252-254 | Unassigned | Private Use | 592 | 255 | Reserved | | 593 +------------+------------------+-------------------------+ 595 Table 4: SFC Echo Request/Echo Reply Message Types 597 8.5. SFC Echo Reply Modes 599 IANA is requested to create in the SFC Echo Request/Echo Reply 600 Parameters registry the new sub-registry Reply Modes All code points 601 in the range 1 through 191 in this registry shall be allocated 602 according to the "IETF Review" procedure as specified in [RFC8126] 603 and assign values as follows: 605 +------------+---------------------------------+--------------------+ 606 | Value | Description | Reference | 607 +------------+---------------------------------+--------------------+ 608 | 0 | Reserved | | 609 | TBA5 | Do Not Reply | This document | 610 | TBA6 | Reply via an IPv4/IPv6 UDP | This document | 611 | | Packet | | 612 | TBA7 | Reply via Application Level | This document | 613 | | Control Channel | | 614 | TBA8 | Reply via Specified Path | This document | 615 | TBA8+1-191 | Unassigned | IETF Review | 616 | 192-251 | Unassigned | First Come First | 617 | | | Served | 618 | 252-254 | Unassigned | Private Use | 619 | 255 | Reserved | | 620 +------------+---------------------------------+--------------------+ 622 Table 5: SFC Echo Reply Modes 624 8.6. SFC Echo Return Codes 626 IANA is requested to create in the SFC Echo Request/Echo Reply 627 Parameters registry the new sub-registry Return Codes: 629 +---------+-------------+-------------------------+ 630 | Value | Description | Reference | 631 +---------+-------------+-------------------------+ 632 | 0-191 | Unassigned | IETF Review | 633 | 192-251 | Unassigned | First Come First Served | 634 | 252-254 | Unassigned | Private Use | 635 | 255 | Reserved | | 636 +---------+-------------+-------------------------+ 638 Table 6: SFC Echo Return Codes 640 Return Codes defined in this document are the following: 642 Value Meaning 643 ----- ------- 644 0 No Return Code 645 1 Malformed echo request received 646 2 One or more of the TLVs was not understood 648 8.7. SFC TLV Type 650 IANA is requested to create SFC OAM TLV Type registry. All code 651 points in the range 1 through 32759 in this registry shall be 652 allocated according to the "IETF Review" procedure as specified in 654 [RFC8126]. Code points in the range 32760 through 65279 in this 655 registry shall be allocated according to the "First Come First 656 Served" procedure as specified in [RFC8126]. Remaining code points 657 are allocated according to the Table 7: 659 +---------------+-------------------------+-------------------------+ 660 | Value | Description | Reference | 661 +---------------+-------------------------+-------------------------+ 662 | 0 | Reserved | This document | 663 | 1- 32767 | Mandatory TLV, | IETF Review | 664 | | unassigned | | 665 | 32768 - 65279 | Optional TLV, | First Come First Served | 666 | | unassigned | | 667 | 65280 - 65519 | Experimental | This document | 668 | 65520 - 65534 | Private Use | This document | 669 | 65535 | Reserved | This document | 670 +---------------+-------------------------+-------------------------+ 672 Table 7: SFC TLV Type Registry 674 This document defines the following new value in SFC OAM TLV Type 675 registry: 677 +-------+-------------------+---------------+ 678 | Value | Description | Reference | 679 +-------+-------------------+---------------+ 680 | TBA9 | Source IP Address | This document | 681 +-------+-------------------+---------------+ 683 Table 8: SFC OAM Source IP Address Type 685 8.8. SFC OAM UDP Port 687 IANA is requested to allocate UDP port number according to 689 +--------+-------+-----------+-------------+------------+-----------+ 690 | Servic | Port | Transport | Description | Semantics | Reference | 691 | e Name | Numbe | Protocol | | Definition | | 692 | | r | | | | | 693 +--------+-------+-----------+-------------+------------+-----------+ 694 | SFC | TBA10 | UDP | SFC OAM | Section | This | 695 | OAM | | | | 5.4 | document | 696 +--------+-------+-----------+-------------+------------+-----------+ 698 Table 9: SFC OAM Port 700 9. References 702 9.1. Normative References 704 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 705 Requirement Levels", BCP 14, RFC 2119, 706 DOI 10.17487/RFC2119, March 1997, 707 . 709 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 710 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 711 May 2017, . 713 [RFC8300] Quinn, P., Ed., Elzur, U., Ed., and C. Pignataro, Ed., 714 "Network Service Header (NSH)", RFC 8300, 715 DOI 10.17487/RFC8300, January 2018, 716 . 718 9.2. Informative References 720 [RFC0792] Postel, J., "Internet Control Message Protocol", STD 5, 721 RFC 792, DOI 10.17487/RFC0792, September 1981, 722 . 724 [RFC1423] Balenson, D., "Privacy Enhancement for Internet Electronic 725 Mail: Part III: Algorithms, Modes, and Identifiers", 726 RFC 1423, DOI 10.17487/RFC1423, February 1993, 727 . 729 [RFC4443] Conta, A., Deering, S., and M. Gupta, Ed., "Internet 730 Control Message Protocol (ICMPv6) for the Internet 731 Protocol Version 6 (IPv6) Specification", STD 89, 732 RFC 4443, DOI 10.17487/RFC4443, March 2006, 733 . 735 [RFC7665] Halpern, J., Ed. and C. Pignataro, Ed., "Service Function 736 Chaining (SFC) Architecture", RFC 7665, 737 DOI 10.17487/RFC7665, October 2015, 738 . 740 [RFC7799] Morton, A., "Active and Passive Metrics and Methods (with 741 Hybrid Types In-Between)", RFC 7799, DOI 10.17487/RFC7799, 742 May 2016, . 744 [RFC8029] Kompella, K., Swallow, G., Pignataro, C., Ed., Kumar, N., 745 Aldrin, S., and M. Chen, "Detecting Multiprotocol Label 746 Switched (MPLS) Data-Plane Failures", RFC 8029, 747 DOI 10.17487/RFC8029, March 2017, 748 . 750 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for 751 Writing an IANA Considerations Section in RFCs", BCP 26, 752 RFC 8126, DOI 10.17487/RFC8126, June 2017, 753 . 755 Authors' Addresses 757 Greg Mirsky 758 ZTE Corp. 760 Email: gregimirsky@gmail.com 762 Wei Meng 763 ZTE Corporation 764 No.50 Software Avenue, Yuhuatai District 765 Nanjing 766 China 768 Email: meng.wei2@zte.com.cn,vally.meng@gmail.com 770 Bhumip Khasnabish 771 Individual contributor 773 Email: vumip1@gmail.com 775 Cui Wang 777 Email: lindawangjoy@gmail.com