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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group D. Farinacci 3 Internet-Draft lispers.net 4 Obsoletes: 6830, 6833 (if approved) F. Maino 5 Intended status: Standards Track Cisco Systems 6 Expires: November 3, 2022 V. Fuller 7 vaf.net Internet Consulting 8 A. Cabellos (Ed.) 9 UPC/BarcelonaTech 10 May 2, 2022 12 Locator/ID Separation Protocol (LISP) Control-Plane 13 draft-ietf-lisp-rfc6833bis-31 15 Abstract 17 This document describes the Control-Plane and Mapping Service for the 18 Locator/ID Separation Protocol (LISP), implemented by two types of 19 LISP-speaking devices -- the LISP Map-Resolver and LISP Map-Server -- 20 that provides a simplified "front end" for one or more Endpoint ID to 21 Routing Locator mapping databases. 23 By using this Control-Plane service interface and communicating with 24 Map-Resolvers and Map-Servers, LISP Ingress Tunnel Routers (ITRs) and 25 Egress Tunnel Routers (ETRs) are not dependent on the details of 26 mapping database systems, which facilitates modularity with different 27 database designs. Since these devices implement the "edge" of the 28 LISP Control-Plane infrastructure, connecting EID addressable nodes 29 of a LISP site, it the implementation and operational complexity of 30 the overall cost and effort of deploying LISP. 32 This document obsoletes RFC 6830 and RFC 6833. 34 Status of This Memo 36 This Internet-Draft is submitted in full conformance with the 37 provisions of BCP 78 and BCP 79. 39 Internet-Drafts are working documents of the Internet Engineering 40 Task Force (IETF). Note that other groups may also distribute 41 working documents as Internet-Drafts. The list of current Internet- 42 Drafts is at https://datatracker.ietf.org/drafts/current/. 44 Internet-Drafts are draft documents valid for a maximum of six months 45 and may be updated, replaced, or obsoleted by other documents at any 46 time. It is inappropriate to use Internet-Drafts as reference 47 material or to cite them other than as "work in progress." 48 This Internet-Draft will expire on November 3, 2022. 50 Copyright Notice 52 Copyright (c) 2022 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 (https://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 . . . . . . . . . . . . . . . . . . . . . . . . 3 68 1.1. Scope of Applicability . . . . . . . . . . . . . . . . . 5 69 2. Requirements Notation . . . . . . . . . . . . . . . . . . . . 5 70 3. Definition of Terms . . . . . . . . . . . . . . . . . . . . . 5 71 4. Basic Overview . . . . . . . . . . . . . . . . . . . . . . . 7 72 5. LISP IPv4 and IPv6 Control-Plane Packet Formats . . . . . . . 8 73 5.1. LISP Control Packet Type Allocations . . . . . . . . . . 11 74 5.2. Map-Request Message Format . . . . . . . . . . . . . . . 12 75 5.3. EID-to-RLOC UDP Map-Request Message . . . . . . . . . . . 14 76 5.4. Map-Reply Message Format . . . . . . . . . . . . . . . . 16 77 5.5. EID-to-RLOC UDP Map-Reply Message . . . . . . . . . . . . 20 78 5.6. Map-Register Message Format . . . . . . . . . . . . . . . 23 79 5.7. Map-Notify/Map-Notify-Ack Message Format . . . . . . . . 27 80 5.8. Encapsulated Control Message Format . . . . . . . . . . . 29 81 6. Changing the Contents of EID-to-RLOC Mappings . . . . . . . . 31 82 6.1. Solicit-Map-Request (SMR) . . . . . . . . . . . . . . . . 31 83 7. Routing Locator Reachability . . . . . . . . . . . . . . . . 32 84 7.1. RLOC-Probing Algorithm . . . . . . . . . . . . . . . . . 33 85 8. Interactions with Other LISP Components . . . . . . . . . . . 34 86 8.1. ITR EID-to-RLOC Mapping Resolution . . . . . . . . . . . 34 87 8.2. EID-Prefix Configuration and ETR Registration . . . . . . 35 88 8.3. Map-Server Processing . . . . . . . . . . . . . . . . . . 37 89 8.4. Map-Resolver Processing . . . . . . . . . . . . . . . . . 37 90 8.4.1. Anycast Operation . . . . . . . . . . . . . . . . . . 38 91 9. Security Considerations . . . . . . . . . . . . . . . . . . . 38 92 10. Privacy Considerations . . . . . . . . . . . . . . . . . . . 40 93 11. Changes since RFC 6833 . . . . . . . . . . . . . . . . . . . 41 94 12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 41 95 12.1. LISP UDP Port Numbers . . . . . . . . . . . . . . . . . 42 96 12.2. LISP Packet Type Codes . . . . . . . . . . . . . . . . . 42 97 12.3. LISP Map-Reply EID-Record Action Codes . . . . . . . . . 42 98 12.4. LISP Address Type Codes . . . . . . . . . . . . . . . . 43 99 12.5. LISP Algorithm ID Numbers . . . . . . . . . . . . . . . 43 100 12.6. LISP Bit Flags . . . . . . . . . . . . . . . . . . . . . 44 101 13. References . . . . . . . . . . . . . . . . . . . . . . . . . 47 102 13.1. Normative References . . . . . . . . . . . . . . . . . . 47 103 13.2. Informative References . . . . . . . . . . . . . . . . . 48 104 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 53 105 Appendix B. Document Change Log . . . . . . . . . . . . . . . . 53 106 B.1. Changes to draft-ietf-lisp-rfc6833bis-31 . . . . . . . . 53 107 B.2. Changes to draft-ietf-lisp-rfc6833bis-26 . . . . . . . . 53 108 B.3. Changes to draft-ietf-lisp-rfc6833bis-25 . . . . . . . . 53 109 B.4. Changes to draft-ietf-lisp-rfc6833bis-24 . . . . . . . . 54 110 B.5. Changes to draft-ietf-lisp-rfc6833bis-23 . . . . . . . . 54 111 B.6. Changes to draft-ietf-lisp-rfc6833bis-22 . . . . . . . . 54 112 B.7. Changes to draft-ietf-lisp-rfc6833bis-21 . . . . . . . . 54 113 B.8. Changes to draft-ietf-lisp-rfc6833bis-20 . . . . . . . . 55 114 B.9. Changes to draft-ietf-lisp-rfc6833bis-19 . . . . . . . . 55 115 B.10. Changes to draft-ietf-lisp-rfc6833bis-18 . . . . . . . . 55 116 B.11. Changes to draft-ietf-lisp-rfc6833bis-17 . . . . . . . . 55 117 B.12. Changes to draft-ietf-lisp-rfc6833bis-16 . . . . . . . . 55 118 B.13. Changes to draft-ietf-lisp-rfc6833bis-15 . . . . . . . . 56 119 B.14. Changes to draft-ietf-lisp-rfc6833bis-14 . . . . . . . . 56 120 B.15. Changes to draft-ietf-lisp-rfc6833bis-13 . . . . . . . . 56 121 B.16. Changes to draft-ietf-lisp-rfc6833bis-12 . . . . . . . . 56 122 B.17. Changes to draft-ietf-lisp-rfc6833bis-11 . . . . . . . . 56 123 B.18. Changes to draft-ietf-lisp-rfc6833bis-10 . . . . . . . . 56 124 B.19. Changes to draft-ietf-lisp-rfc6833bis-09 . . . . . . . . 57 125 B.20. Changes to draft-ietf-lisp-rfc6833bis-08 . . . . . . . . 57 126 B.21. Changes to draft-ietf-lisp-rfc6833bis-07 . . . . . . . . 57 127 B.22. Changes to draft-ietf-lisp-rfc6833bis-06 . . . . . . . . 58 128 B.23. Changes to draft-ietf-lisp-rfc6833bis-05 . . . . . . . . 58 129 B.24. Changes to draft-ietf-lisp-rfc6833bis-04 . . . . . . . . 58 130 B.25. Changes to draft-ietf-lisp-rfc6833bis-03 . . . . . . . . 58 131 B.26. Changes to draft-ietf-lisp-rfc6833bis-02 . . . . . . . . 59 132 B.27. Changes to draft-ietf-lisp-rfc6833bis-01 . . . . . . . . 59 133 B.28. Changes to draft-ietf-lisp-rfc6833bis-00 . . . . . . . . 59 134 B.29. Changes to draft-farinacci-lisp-rfc6833bis-00 . . . . . . 59 135 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 60 137 1. Introduction 139 The Locator/ID Separation Protocol [I-D.ietf-lisp-rfc6830bis] (see 140 also [I-D.ietf-lisp-introduction]) specifies an architecture and 141 mechanism for dynamic tunneling by logically separating the addresses 142 currently used by IP in two separate name spaces: Endpoint IDs 143 (EIDs), used within sites; and Routing Locators (RLOCs), used on the 144 transit networks that make up the Internet infrastructure. To 145 achieve this separation, LISP defines protocol mechanisms for mapping 146 from EIDs to RLOCs. In addition, LISP assumes the existence of a 147 database to store and propagate those mappings across mapping system 148 nodes. Several such databases have been proposed; among them are the 149 Content distribution Overlay Network Service for LISP-NERD (a Not-so- 150 novel EID-to-RLOC Database) [RFC6837], LISP Alternative Logical 151 Topology (LISP-ALT) [RFC6836], and LISP Delegated Database Tree 152 (LISP-DDT) [RFC8111]. 154 The LISP Mapping Service defines two types of LISP-speaking devices: 155 the Map-Resolver, which accepts Map-Requests from an Ingress Tunnel 156 Router (ITR) and "resolves" the EID-to-RLOC mapping using a mapping 157 database; and the Map-Server, which learns authoritative EID-to-RLOC 158 mappings from an Egress Tunnel Router (ETR) and publishes them in a 159 database. 161 This LISP Control-Plane Mapping Service can be used by many different 162 encapsulation-based or translation-based Data-Planes which include 163 but are not limited to the ones defined in LISP RFC 6830bis 164 [I-D.ietf-lisp-rfc6830bis], LISP-GPE [I-D.ietf-lisp-gpe], VXLAN 165 [RFC7348], VXLAN-GPE [I-D.ietf-nvo3-vxlan-gpe], GRE [RFC2890], GTP 166 [GTP-3GPP], ILA [I-D.herbert-intarea-ila], and Segment Routing (SRv6) 167 [RFC8402]. 169 Conceptually, LISP Map-Servers share some of the same basic 170 configuration and maintenance properties as Domain Name System (DNS) 171 [RFC1035] servers; likewise, Map-Resolvers are conceptually similar 172 to DNS caching resolvers. With this in mind, this specification 173 borrows familiar terminology (resolver and server) from the DNS 174 specifications. 176 Note this document doesn't assume any particular database mapping 177 infrastructure to illustrate certain aspects of Map-Server and Map- 178 Resolver operation. The Mapping Service interface can (and likely 179 will) be used by ITRs and ETRs to access other mapping database 180 systems as the LISP infrastructure evolves. 182 LISP is not intended to address problems of connectivity and scaling 183 on behalf of arbitrary communicating parties. Relevant situations 184 are described in the scoping section of the introduction to 185 [I-D.ietf-lisp-rfc6830bis]. 187 This document obsoletes RFC 6830 and 6833. 189 1.1. Scope of Applicability 191 LISP was originally developed to address the Internet-wide route 192 scaling problem [RFC4984]. While there are a number of approaches of 193 interest for that problem, as LISP as been developed and refined, a 194 large number of other LISP uses have been found and are being used. 195 As such, the design and development of LISP has changed so as to 196 focus on these use cases. The common property of these uses is a 197 large set of cooperating entities seeking to communicate over the 198 public Internet or other large underlay IP infrastructures, while 199 keeping the addressing and topology of the cooperating entities 200 separate from the underlay and Internet topology, routing, and 201 addressing. 203 When communicating over the public Internet, deployers MUST consider 204 the following guidelines: 206 1. LISP-SEC MUST be implemented [I-D.ietf-lisp-sec]. This means 207 that the S-bit MUST be set in the Map-Reply (Section 5.4), Map- 208 Register (Section 5.6) and Encapsulated Control messages 209 (Section 5.8). 211 2. Implementations SHOULD use the 'HMAC-SHA256-128+HKDF-SHA256' as 212 the Algorithm ID (Section 12.5) in Map-Register message 213 (Section 5.6), and MUST NOT use 'None' or 'HMAC-SHA-1-96-None' as 214 Algorithm ID (Section 12.5) in the Map-Register message 215 (Section 5.6) 217 2. Requirements Notation 219 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 220 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 221 "OPTIONAL" in this document are to be interpreted as described in BCP 222 14 [RFC2119] [RFC8174] when, and only when, they appear in all 223 capitals, as shown here. 225 3. Definition of Terms 227 Map-Server: A network infrastructure component that learns of EID- 228 Prefix mapping entries from an ETR, via the registration mechanism 229 described below, or some other authoritative source if one exists. 230 A Map-Server publishes these EID-Prefixes in a mapping database. 232 Map-Request: A LISP Map-Request is a Control-Plane message to query 233 the mapping system to resolve an EID. A LISP Map-Request can also 234 be sent to an RLOC to test for reachability and to exchange 235 security keys between an encapsulator and a decapsulator. This 236 type of Map-Request is also known as an RLOC-Probe Request. 238 Map-Reply: A LISP Map-Reply is a Control-Plane message returned in 239 response to a Map-Request sent to the mapping system when 240 resolving an EID. A LISP Map-Reply can also be returned by a 241 decapsulator in response to a Map-Request sent by an encapsulator 242 to test for reachability. This type of Map-Reply is known as a 243 RLOC-Probe Reply. 245 Encapsulated Map-Request: A LISP Map-Request carried within an 246 Encapsulated Control Message (ECM), which has an additional LISP 247 header prepended. Sent to UDP destination port 4342. The "outer" 248 addresses are routable IP addresses, also known as RLOCs. Used by 249 an ITR when sending to a Map-Resolver and by a Map-Server when 250 forwarding a Map-Request to an ETR. 252 Map-Resolver: A network infrastructure component that accepts LISP 253 Encapsulated (ECM) Map-Requests, typically from an ITR, and 254 determines whether or not the destination IP address is part of 255 the EID namespace; if it is not, a Negative Map-Reply is returned. 256 Otherwise, the Map-Resolver finds the appropriate EID-to-RLOC 257 mapping by consulting a mapping database system. 259 Negative Map-Reply: A LISP Map-Reply that contains an empty 260 Locator-Set. Returned in response to a Map-Request if the 261 destination EID is not registered in the mapping system, is policy 262 denied or fails authentication. 264 Map-Register message: A LISP message sent by an ETR to a Map-Server 265 to register its associated EID-Prefixes. In addition to the set 266 of EID-Prefixes to register, the message includes one or more 267 RLOCs to reach ETR(s). The Map-Server uses these RLOCs when 268 forwarding Map-Requests (re-formatted as Encapsulated Map- 269 Requests). An ETR MAY request that the Map-Server answer Map- 270 Requests on its behalf by setting the "proxy Map-Reply" flag 271 (P-bit) in the message. 273 Map-Notify message: A LISP message sent by a Map-Server to an ETR 274 to confirm that a Map-Register has been received and processed. 275 An ETR requests that a Map-Notify be returned by setting the 276 "want-map-notify" flag (M-bit) in the Map-Register message. 277 Unlike a Map-Reply, a Map-Notify uses UDP port 4342 for both 278 source and destination. Map-Notify messages are also sent to ITRs 279 by Map-Servers when there are RLOC-set changes. 281 For definitions of other terms, notably Ingress Tunnel Router (ITR), 282 Egress Tunnel Router (ETR), and Re-encapsulating Tunnel Router (RTR), 283 refer to the LISP Data-Plane specification 284 [I-D.ietf-lisp-rfc6830bis]. 286 4. Basic Overview 288 A Map-Server is a device that publishes EID-Prefixes in a LISP 289 mapping database on behalf of a set of ETRs. When it receives a Map 290 Request (typically originating from an ITR), it consults the mapping 291 database to find an ETR that can answer with the set of RLOCs for an 292 EID-Prefix. To publish its EID-Prefixes, an ETR periodically sends 293 Map-Register messages to the Map-Server. A Map-Register message 294 contains a list of EID-Prefixes plus a set of RLOCs that can be used 295 to reach the ETRs. 297 When LISP-ALT [RFC6836] is used as the mapping database, a Map-Server 298 connects to the ALT network and acts as a "last-hop" ALT-Router. 299 Intermediate ALT-Routers forward Map-Requests to the Map-Server that 300 advertises a particular EID-Prefix, and the Map-Server forwards them 301 to the owning ETR, which responds with Map-Reply messages. 303 When LISP-DDT [RFC8111] is used as the mapping database, a Map-Server 304 sends the final Map-Referral messages from the Delegated Database 305 Tree. 307 A Map-Resolver receives Encapsulated Map-Requests from its client 308 ITRs and uses a mapping database system to find the appropriate ETR 309 to answer those requests. On a LISP-ALT network, a Map-Resolver acts 310 as a "first-hop" ALT-Router. It has Generic Routing Encapsulation 311 (GRE) tunnels configured to other ALT-Routers and uses BGP to learn 312 paths to ETRs for different prefixes in the LISP-ALT database. The 313 Map-Resolver uses this path information to forward Map-Requests over 314 the ALT to the correct ETRs. On a LISP-DDT network [RFC8111], a Map- 315 Resolver maintains a referral-cache and acts as a "first-hop" DDT- 316 node. The Map-Resolver uses the referral information to forward Map- 317 Requests. 319 Note that while it is conceivable that a Map-Resolver could cache 320 responses to improve performance, issues surrounding cache management 321 would need to be resolved so that doing so will be reliable and 322 practical. In this specification, Map-Resolvers will operate only in 323 a non-caching mode, decapsulating and forwarding Encapsulated Map 324 Requests received from ITRs. Any specification of caching 325 functionality is out of scope for this document. 327 Note that a single device can implement the functions of both a Map- 328 Server and a Map-Resolver, and in many cases the functions will be 329 co-located in that way. Also, there can be ALT-only nodes and DDT- 330 only nodes, when LISP-ALT and LISP-DDT are used, respectively, to 331 connecting Map-Resolvers and Map-Servers together to make up the 332 Mapping System. 334 5. LISP IPv4 and IPv6 Control-Plane Packet Formats 336 The following UDP packet formats are used by the LISP control plane. 338 0 1 2 3 339 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 1 340 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 341 |Version| IHL |Type of Service| Total Length | 342 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 343 | Identification |Flags| Fragment Offset | 344 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 345 | Time to Live | Protocol = 17 | Header Checksum | 346 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 347 | Source Routing Locator | 348 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 349 | Destination Routing Locator | 350 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 351 / | Source Port | Dest Port | 352 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 353 \ | UDP Length | UDP Checksum | 354 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 355 | | 356 | LISP Message | 357 | | 358 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 360 IPv4 UDP LISP Control Message 362 0 1 2 3 363 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 1 364 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 365 |Version| Traffic Class | Flow Label | 366 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 367 | Payload Length | Next Header=17| Hop Limit | 368 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 369 | | 370 + + 371 | | 372 + Source Routing Locator + 373 | | 374 + + 375 | | 376 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 377 | | 378 + + 379 | | 380 + Destination Routing Locator + 381 | | 382 + + 383 | | 384 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 385 / | Source Port | Dest Port | 386 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 387 \ | UDP Length | UDP Checksum | 388 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 389 | | 390 | LISP Message | 391 | | 392 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 394 IPv6 UDP LISP Control Message 396 When a UDP Map-Request, Map-Register, or Map-Notify (when used as a 397 notification message) are sent, the UDP source port is chosen by the 398 sender and the destination UDP port number is set to 4342. When a 399 UDP Map-Reply, Map-Notify (when used as an acknowledgement to a Map- 400 Register), or Map-Notify-Ack are sent, the source UDP port number is 401 set to 4342 and the destination UDP port number is copied from the 402 source port of either the Map-Request or the invoking data packet. 403 Implementations MUST be prepared to accept packets when either the 404 source port or destination UDP port is set to 4342 due to NATs 405 changing port number values. 407 The 'UDP Length' field will reflect the length of the UDP header and 408 the LISP Message payload. LISP is expected to be deployed by 409 cooperating entities communicating over underlays. Deployers are 410 expected to set the MTU according to the specific deployment 411 guidelines to prevent fragmentation of either the inner packet or the 412 outer encapsulated packet. For deployments not aware of the underlay 413 restrictions on path MTU, the message size MUST be limited to 576 414 bytes for IPv4 or 1280 bytes for IPv6 -considering the entire IP 415 packet- as outlined in [RFC8085]. 417 The UDP checksum is computed and set to non-zero for all messages 418 sent to or from port 4342. It MUST be checked on receipt, and if the 419 checksum fails, the control message MUST be dropped [RFC1071]. 421 The format of control messages includes the UDP header so the 422 checksum and length fields can be used to protect and delimit message 423 boundaries. 425 5.1. LISP Control Packet Type Allocations 427 This section defines the LISP control message formats and summarizes 428 for IANA the LISP Type codes assigned by this document. For 429 completeness, the summary below includes the LISP Shared Extension 430 Message assigned by [I-D.ietf-lisp-rfc8113bis]. Message type 431 definitions are: 433 Reserved: 0 b'0000' 434 LISP Map-Request: 1 b'0001' 435 LISP Map-Reply: 2 b'0010' 436 LISP Map-Register: 3 b'0011' 437 LISP Map-Notify: 4 b'0100' 438 LISP Map-Notify-Ack: 5 b'0101' 439 LISP Map-Referral: 6 b'0110' 440 Unassigned 7 b'0111' 441 LISP Encapsulated Control Message: 8 b'1000' 442 Unassigned 9-14 b'1001'- b'1110' 443 LISP Shared Extension Message: 15 b'1111' 445 Protocol designers experimenting with new message formats are 446 recommended to use the LISP Shared Extension Message Type described 447 in [I-D.ietf-lisp-rfc8113bis]. 449 All LISP Control-Plane messages use Address Family Identifiers (AFI) 450 [AFI] or LISP Canonical Address Format (LCAF) [RFC8060] formats to 451 encode either fixed or variable length addresses. This includes 452 explicit fields in each control message or part of EID-records or 453 RLOC-records in commonly formatted messages. LISP control-plane 454 messages that include an unrecognized AFI MUST be dropped and the 455 event MUST be logged. 457 The LISP control-plane describes how other data-planes can encode 458 messages to support the Soliciting of Map-Requests as well as RLOC- 459 probing procedures. 461 5.2. Map-Request Message Format 463 0 1 2 3 464 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 1 465 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 466 |Type=1 |A|M|P|S|p|s|R|R| Rsvd |L|D| IRC | Record Count | 467 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 468 | Nonce . . . | 469 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 470 | . . . Nonce | 471 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 472 | Source-EID-AFI | Source EID Address ... | 473 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 474 | ITR-RLOC-AFI 1 | ITR-RLOC Address 1 ... | 475 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 476 | ... | 477 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 478 | ITR-RLOC-AFI n | ITR-RLOC Address n ... | 479 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 480 / | Reserved | EID mask-len | EID-Prefix-AFI | 481 Rec +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 482 \ | EID-Prefix ... | 483 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 484 | Map-Reply Record ... | 485 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 487 Packet field descriptions: 489 Type: 1 (Map-Request) 491 A: This is an authoritative bit, it is set to 1 when an ITR wants the 492 destination site to return the Map-Reply rather than the mapping 493 database system returning a Map-Reply, and set to 0 otherwise. 495 M: This is the map-data-present bit. When set, it indicates that a 496 Map-Reply Record segment is included in the Map-Request. 498 P: This is the probe-bit, which indicates that a Map-Request MUST be 499 treated as a Locator reachability probe. The receiver MUST 500 respond with a Map-Reply with the probe-bit set, indicating that 501 the Map-Reply is a Locator reachability probe reply, with the 502 nonce copied from the Map-Request. See RLOC-Probing Section 7.1 503 for more details. This RLOC-probe Map-Request MUST NOT be sent to 504 the mapping system. If a Map-Resolver or Map-Server receives a 505 Map-Request with the probe-bit set, it MUST drop the message. 507 S: This is the Solicit-Map-Request (SMR) bit. See Solicit-Map- 508 Request (SMRs) Section 6.1 for details. 510 p: This is the PITR bit. This bit is set to 1 when a PITR sends a 511 Map-Request. The use of this bit is deployment-specific. 513 s: This is the SMR-invoked bit. This bit is set to 1 when an xTR is 514 sending a Map-Request in response to a received SMR-based Map- 515 Request. 517 R: This reserved and unassigned bit MUST be set to 0 on transmit and 518 MUST be ignored on receipt. 520 Rsvd: This field MUST be set to 0 on transmit and MUST be ignored on 521 receipt. 523 L: This is the local-xtr bit. It is used by an xTR in a LISP site to 524 tell other xTRs in the same site that it is part of the RLOC-set 525 for the LISP site. The L-bit is set to 1 when the RLOC is the 526 sender's IP address. 528 D: This is the dont-map-reply bit. It is used in the SMR procedure 529 described in Section 6.1. When an xTR sends an SMR message, it 530 doesn't need a Map-Reply returned. When this bit is set, the 531 receiver of the Map-Request does not return a Map-Reply. 533 IRC: This 5-bit field is the ITR-RLOC Count, which encodes the 534 additional number of ('ITR-RLOC-AFI', 'ITR-RLOC Address') fields 535 present in this message. At least one (ITR-RLOC-AFI, ITR-RLOC- 536 Address) pair MUST be encoded. Multiple 'ITR-RLOC Address' fields 537 are used, so a Map-Replier can select which destination address to 538 use for a Map-Reply. The IRC value ranges from 0 to 31. For a 539 value of 0, there is 1 ITR-RLOC address encoded; for a value of 1, 540 there are 2 ITR-RLOC addresses encoded, and so on up to 31, which 541 encodes a total of 32 ITR-RLOC addresses. 543 Record Count: This is the number of records in this Map-Request 544 message. A record is comprised of the portion of the packet that 545 is labeled 'Rec' above and occurs the number of times equal to 546 Record Count. For this version of the protocol, a receiver MUST 547 accept and process Map-Requests that contain one or more records, 548 but a sender MUST only send Map-Requests containing one record. 550 Nonce: This is an 8-octet random value created by the sender of the 551 Map-Request. This nonce will be returned in the Map-Reply. The 552 nonce is used as an index to identify the corresponding Map- 553 Request when a Map-Reply message is received. The nonce MUST be 554 generated by a properly seeded pseudo-random source, see as an 555 example [RFC4086]. 557 Source-EID-AFI: This is the address family of the 'Source EID 558 Address' field. 560 Source EID Address: This is the EID of the source host that 561 originated the packet that caused the Map-Request. When Map- 562 Requests are used for refreshing a Map-Cache entry or for RLOC- 563 Probing, an AFI value 0 is used and this field is of zero length. 565 ITR-RLOC-AFI: This is the address family of the 'ITR-RLOC Address' 566 field that follows this field. 568 ITR-RLOC Address: This is used to give the ETR the option of 569 selecting the destination address from any address family for the 570 Map-Reply message. This address MUST be a routable RLOC address 571 of the sender of the Map-Request message. 573 EID mask-len: This is the mask length for the EID-Prefix. 575 EID-Prefix-AFI: This is the address family of the EID-Prefix 576 according to [AFI] and [RFC8060]. 578 EID-Prefix: This prefix address length is 4 octets for an IPv4 579 address family and 16 octets for an IPv6 address family when the 580 EID-Prefix-AFI is 1 or 2, respectively. For other AFIs [AFI], the 581 address length varies and for the LCAF AFI the format is defined 582 in [RFC8060]. When a Map-Request is sent by an ITR because a data 583 packet is received for a destination where there is no mapping 584 entry, the EID-Prefix is set to the destination IP address of the 585 data packet, and the 'EID mask-len' is set to 32 or 128 for IPv4 586 or IPv6, respectively. When an xTR wants to query a site about 587 the status of a mapping it already has cached, the EID-Prefix used 588 in the Map-Request has the same mask-length as the EID-Prefix 589 returned from the site when it sent a Map-Reply message. 591 Map-Reply Record: When the M-bit is set, this field is the size of a 592 single "Record" in the Map-Reply format. This Map-Reply record 593 contains the EID-to-RLOC mapping entry associated with the Source 594 EID. This allows the ETR that will receive this Map-Request to 595 cache the data if it chooses to do so. It is important to note 596 that this mapping has not been validated by the Mapping System. 598 5.3. EID-to-RLOC UDP Map-Request Message 600 A Map-Request is sent from an ITR when it needs a mapping for an EID, 601 wants to test an RLOC for reachability, or wants to refresh a mapping 602 before TTL expiration. For the initial case, the destination IP 603 address used for the Map-Request is the data packet's destination 604 address (i.e., the destination EID) that had a mapping cache lookup 605 failure. For the latter two cases, the destination IP address used 606 for the Map-Request is one of the RLOC addresses from the Locator-Set 607 of the Map-Cache entry. The source address is either an IPv4 or IPv6 608 RLOC address, depending on whether the Map-Request is using an IPv4 609 or IPv6 header, respectively. In all cases, the UDP source port 610 number for the Map-Request message is a 16-bit value selected by the 611 ITR/PITR, and the UDP destination port number is set to the well- 612 known destination port number 4342. A successful Map-Reply, which is 613 one that has a nonce that matches an outstanding Map-Request nonce, 614 will update the cached set of RLOCs associated with the EID-Prefix 615 range. 617 One or more Map-Request ('ITR-RLOC-AFI', 'ITR-RLOC-Address') fields 618 MUST be filled in by the ITR. The number of fields (minus 1) encoded 619 MUST be placed in the 'IRC' field. The ITR MAY include all locally 620 configured Locators in this list or just provide one locator address 621 from each address family it supports. If the ITR erroneously 622 provides no ITR-RLOC addresses, the Map-Replier MUST drop the Map- 623 Request. 625 Map-Requests can also be LISP encapsulated using UDP destination 626 port 4342 with a LISP Type value set to "Encapsulated Control 627 Message", when sent from an ITR to a Map-Resolver. Likewise, Map- 628 Requests are LISP encapsulated the same way from a Map-Server to an 629 ETR. Details on Encapsulated Map-Requests and Map-Resolvers can be 630 found in Section 5.8. 632 Map-Requests MUST be rate-limited to 1 per second per EID-prefix. 633 After 10 retransmits without receiving the corresponding Map-Reply 634 the sender MUST wait 30 seconds. 636 An ITR that is configured with mapping database information (i.e., it 637 is also an ETR) MAY optionally include those mappings in a Map- 638 Request. When an ETR configured to accept and verify such 639 "piggybacked" mapping data receives such a Map-Request and it does 640 not have this mapping in the Map-Cache, it MUST originate a 641 "verifying Map-Request" through the mapping database to validate thge 642 "piggybacked" mapping data. 644 5.4. Map-Reply Message Format 646 0 1 2 3 647 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 1 648 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 649 |Type=2 |P|E|S| Reserved | Record Count | 650 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 651 | Nonce . . . | 652 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 653 | . . . Nonce | 654 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 655 | | Record TTL | 656 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 657 R | Locator Count | EID mask-len | ACT |A| Reserved | 658 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 659 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 660 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 661 r | EID-Prefix | 662 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 663 | /| Priority | Weight | M Priority | M Weight | 664 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 665 | o | Unused Flags |L|p|R| Loc-AFI | 666 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 667 | \| Locator | 668 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 670 Packet field descriptions: 672 Type: 2 (Map-Reply) 674 P: This is the probe-bit, which indicates that the Map-Reply is in 675 response to a Locator reachability probe Map-Request. The 'Nonce' 676 field must contain a copy of the nonce value from the original 677 Map-Request. See RLOC-probing Section 7.1 for more details. When 678 the probe-bit is set to 1 in a Map-Reply message, the A-bit in 679 each EID-record included in the message MUST be set to 1, 680 otherwise MUST be silently discarded. 682 E: This bit indicates that the ETR that sends this Map-Reply message 683 is advertising that the site is enabled for the Echo-Nonce Locator 684 reachability algorithm. See Echo-Nonce [I-D.ietf-lisp-rfc6830bis] 685 for more details. 687 S: This is the Security bit. When set to 1, the following 688 authentication information will be appended to the end of the Map- 689 Reply. The details can be found in [I-D.ietf-lisp-sec]. 691 0 1 2 3 692 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 1 693 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 694 | AD Type | Authentication Data Content . . . | 695 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 697 Reserved: This unassigned field MUST be set to 0 on transmit and 698 MUST be ignored on receipt. 700 Record Count: This is the number of records in this reply message. 701 A record is comprised of that portion of the packet labeled 702 'Record' above and occurs the number of times equal to Record 703 Count. Note that the reply count can be larger than the requested 704 count, for instance when more-specifics are present. 706 Nonce: This 64-bit value from the Map-Request is echoed in this 707 'Nonce' field of the Map-Reply. 709 Record TTL: This is the time in minutes the recipient of the Map- 710 Reply can store the mapping. If the TTL is 0, the entry MUST be 711 removed from the cache immediately. If the value is 0xffffffff, 712 the recipient can decide locally how long to store the mapping. 714 Locator Count: This is the number of Locator entries in the given 715 Record. A Locator entry comprises what is labeled above as 'Loc'. 716 The Locator count can be 0, indicating that there are no Locators 717 for the EID-Prefix. 719 EID mask-len: This is the mask length for the EID-Prefix. 721 ACT: This 3-bit field describes Negative Map-Reply actions. In any 722 other message type, these bits are set to 0 and ignored on 723 receipt. These bits are used only when the 'Locator Count' field 724 is set to 0. The action bits are encoded only in Map-Reply 725 messages. They are used to tell an ITR or PITR why a empty 726 locator-set was returned from the mapping system and how it stores 727 the map-cache entry. See Section 12.3 for additional information. 729 (0) No-Action: The Map-Cache is kept alive, and no packet 730 encapsulation occurs. 732 (1) Natively-Forward: The packet is not encapsulated or dropped 733 but natively forwarded. 735 (2) Send-Map-Request: The Map-Cache entry is created and flagged 736 that any packet matching this entry invokes sending a Map- 737 Request. 739 (3) Drop/No-Reason: A packet that matches this Map-Cache entry is 740 dropped. An ICMP Destination Unreachable message SHOULD be 741 sent. 743 (4) Drop/Policy-Denied: A packet that matches this Map-Cache 744 entry is dropped. The reason for the Drop action is that a 745 Map-Request for the target-EID is being policy denied by 746 either an xTR or the mapping system. 748 (5) Drop/Authentication-Failure: A packet that matches this Map- 749 Cache entry is dropped. The reason for the Drop action is 750 that a Map-Request for the target-EID fails an authentication 751 verification-check by either an xTR or the mapping system. 753 A: The Authoritative bit MAY only be set to 1 by an ETR. A Map- 754 Server generating Map-Reply messages as a proxy MUST NOT set the 755 A-bit to 1. This bit indicates to the requesting ITRs if the Map- 756 Reply was originated by a LISP node managed at the site that owns 757 the EID-Prefix. 759 Map-Version Number: When this 12-bit value in an EID-record of a 760 Map-Reply message is non-zero, follow the procedures in 761 [I-D.ietf-lisp-6834bis] for details. 763 EID-Prefix-AFI: Address family of the EID-Prefix according to [AFI] 764 and [RFC8060]. 766 EID-Prefix: This prefix is 4 octets for an IPv4 address family and 767 16 octets for an IPv6 address family. 769 Priority: Each RLOC is assigned a unicast Priority. Lower values 770 are more preferable. When multiple RLOCs have the same Priority, 771 they may be used in a load-split fashion. A value of 255 means 772 the RLOC MUST NOT be used for unicast forwarding. 774 Weight: When priorities are the same for multiple RLOCs, the Weight 775 indicates how to balance unicast traffic between them. Weight is 776 encoded as a relative weight of total unicast packets that match 777 the mapping entry. For example, if there are 4 Locators in a 778 Locator-Set, where the Weights assigned are 30, 20, 20, and 10, 779 the first Locator will get 37.5% of the traffic, the 2nd and 3rd 780 Locators will each get 25% of the traffic, and the 4th Locator 781 will get 12.5% of the traffic. If all Weights for a Locator-Set 782 are equal, the receiver of the Map-Reply will decide how to load- 783 split the traffic. See RLOC-hashing [I-D.ietf-lisp-rfc6830bis] 784 for a suggested hash algorithm to distribute the load across 785 Locators with the same Priority and equal Weight values. 787 M Priority: Each RLOC is assigned a multicast Priority used by an 788 ETR in a receiver multicast site to select an ITR in a source 789 multicast site for building multicast distribution trees. A value 790 of 255 means the RLOC MUST NOT be used for joining a multicast 791 distribution tree. For more details, see [RFC6831]. 793 M Weight: When priorities are the same for multiple RLOCs, the 794 Weight indicates how to balance building multicast distribution 795 trees across multiple ITRs. The Weight is encoded as a relative 796 weight (similar to the unicast Weights) of the total number of 797 trees built to the source site identified by the EID-Prefix. If 798 all Weights for a Locator-Set are equal, the receiver of the Map- 799 Reply will decide how to distribute multicast state across ITRs. 800 For more details, see [RFC6831]. 802 Unused Flags: These are set to 0 when sending and ignored on 803 receipt. 805 L: When this bit is set, the Locator is flagged as a local Locator to 806 the ETR that is sending the Map-Reply. When a Map-Server is doing 807 proxy Map-Replying for a LISP site, the L-bit is set to 0 for all 808 Locators in this Locator-Set. 810 p: When this bit is set, an ETR informs the RLOC-Probing ITR that the 811 locator address for which this bit is set is the one being RLOC- 812 probed and may be different from the source address of the Map- 813 Reply. An ITR that RLOC-probes a particular Locator MUST use this 814 Locator for retrieving the data structure used to store the fact 815 that the Locator is reachable. The p-bit is set for a single 816 Locator in the same Locator-Set. If an implementation sets more 817 than one p-bit erroneously, the receiver of the Map-Reply MUST 818 select the first set p-bit Locator. The p-bit MUST NOT be set for 819 Locator-Set records sent in Map-Request and Map-Register messages. 821 R: This is set when the sender of a Map-Reply has a route to the 822 Locator in the Locator data record. This receiver may find this 823 useful to know if the Locator is up but not necessarily reachable 824 from the receiver's point of view. 826 Locator: This is an IPv4 or IPv6 address (as encoded by the 'Loc- 827 AFI' field) assigned to an ETR and used by an ITR as a destination 828 RLOC address in the outer header of a LISP encapsulated packet. 829 Note that the destination RLOC address of a LISP encapsulated 830 packet MAY be an anycast address. A source RLOC of a LISP 831 encapsulated packet can be an anycast address as well. The source 832 or destination RLOC MUST NOT be the broadcast address 833 (255.255.255.255 or any subnet broadcast address known to the 834 router) and MUST NOT be a link-local multicast address. The 835 source RLOC MUST NOT be a multicast address. The destination RLOC 836 SHOULD be a multicast address if it is being mapped from a 837 multicast destination EID. 839 Map-Reply MUST be rate-limited, it is RECOMMENDED that a Map-Reply 840 for the same destination RLOC be sent no more than one packets per 3 841 seconds. 843 The Record format, as defined here, is used both in the Map-Reply and 844 Map-Register messages, this includes all the field definitions. 846 5.5. EID-to-RLOC UDP Map-Reply Message 848 A Map-Reply returns an EID-Prefix with a mask-length that is less 849 than or equal to the EID being requested. The EID being requested is 850 either from the destination field of an IP header of a Data-Probe or 851 the EID of a record of a Map-Request. The RLOCs in the Map-Reply are 852 routable IP addresses of all ETRs for the LISP site. Each RLOC 853 conveys status reachability but does not convey path reachability 854 from a requester's perspective. Separate testing of path 855 reachability is required. See RLOC-reachability Section 7.1 for 856 details. 858 Note that a Map-Reply MAY contain different EID-Prefix granularity 859 (prefix + mask-length) than the Map-Request that triggers it. This 860 might occur if a Map-Request were for a prefix that had been returned 861 by an earlier Map-Reply. In such a case, the requester updates its 862 cache with the new prefix information and granularity. For example, 863 a requester with two cached EID-Prefixes that are covered by a Map- 864 Reply containing one less-specific prefix replaces the entry with the 865 less-specific EID-Prefix. Note that the reverse, replacement of one 866 less-specific prefix with multiple more-specific prefixes, can also 867 occur, not by removing the less-specific prefix but rather by adding 868 the more-specific prefixes that, during a lookup, will override the 869 less-specific prefix. 871 When an EID moves out of a LISP site [I-D.ietf-lisp-eid-mobility], 872 the database mapping system may have overlapping EID-prefixes. Or 873 when a LISP site is configured with multiple sets of ETRs that 874 support different EID-prefix mask-lengths, the database mapping 875 system may have overlapping EID-prefixes. When overlapping EID- 876 prefixes exist, a Map-Request with an EID that best matches any EID- 877 Prefix MUST be returned in a single Map-Reply message. For instance, 878 if an ETR had database mapping entries for EID-Prefixes: 880 2001:db8::/32 881 2001:db8:1::/48 882 2001:db8:1:1::/64 883 2001:db8:1:2::/64 885 A Map-Request for EID 2001:db8:1:1::1 would cause a Map-Reply with a 886 record count of 1 to be returned with a mapping record EID-Prefix of 887 2001:db8:1:1::/64. 889 A Map-Request for EID 2001:db8:1:5::5 would cause a Map-Reply with a 890 record count of 3 to be returned with mapping records for EID- 891 Prefixes 2001:db8:1::/48, 2001:db8:1:1::/64, 2001:db8:1:2::/64, 892 filling out the /48 with more-specifics that exist in the mapping 893 system. 895 Note that not all overlapping EID-Prefixes need to be returned but 896 only the more-specific entries (note that in the second example above 897 2001:db8::/32 was not returned for requesting EID 2001:db8:1:5::5) 898 for the matching EID-Prefix of the requesting EID. When more than 899 one EID-Prefix is returned, all SHOULD use the same Time to Live 900 value so they can all time out at the same time. When a more- 901 specific EID-Prefix is received later, its Time to Live value in the 902 Map-Reply record can be stored even when other less-specific entries 903 exist. When a less-specific EID-Prefix is received later, its Map- 904 Cache expiration time SHOULD be set to the minimum expiration time of 905 any more-specific EID-Prefix in the Map-Cache. This is done so the 906 integrity of the EID-Prefix set is wholly maintained and so no more- 907 specific entries are removed from the Map-Cache while keeping less- 908 specific entries. 910 For scalability, it is expected that aggregation of EID addresses 911 into EID-Prefixes will allow one Map-Reply to satisfy a mapping for 912 the EID addresses in the prefix range, thereby reducing the number of 913 Map-Request messages. 915 Map-Reply records can have an empty Locator-Set. A Negative Map- 916 Reply is a Map-Reply with an empty Locator-Set. Negative Map-Replies 917 convey special actions by the sender to the ITR or PITR that have 918 solicited the Map-Reply. There are two primary applications for 919 Negative Map-Replies. The first is for a Map-Resolver to instruct an 920 ITR or PITR when a destination is for a LISP site versus a non-LISP 921 site, and the other is to source quench Map-Requests that are sent 922 for non-allocated EIDs. 924 For each Map-Reply record, the list of Locators in a Locator-Set MUST 925 be sorted in order of ascending IP address where an IPv4 locator 926 address is considered numerically 'less than' an IPv6 locator 927 address. 929 When sending a Map-Reply message, the destination address is copied 930 from one of the 'ITR-RLOC' fields from the Map-Request. The ETR can 931 choose a locator address from one of the address families it 932 supports. For Data-Probes, the destination address of the Map-Reply 933 is copied from the source address of the Data-Probe message that is 934 invoking the reply. The source address of the Map-Reply is one of 935 the local IP addresses chosen, to allow Unicast Reverse Path 936 Forwarding (uRPF) checks to succeed in the upstream service provider. 937 The destination port of a Map-Reply message is copied from the source 938 port of the Map-Request or Data-Probe, and the source port of the 939 Map-Reply message is set to the well-known UDP port 4342. 941 5.6. Map-Register Message Format 943 This section specifies the encoding format for the Map-Register 944 message. The message is sent in UDP with a destination UDP port of 945 4342 and a randomly selected UDP source port number. 947 The fields below are used in multiple control messages. They are 948 defined for Map-Register, Map-Notify and Map-Notify-Ack message 949 types. 951 The Map-Register message format is: 953 0 1 2 3 954 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 1 955 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 956 |Type=3 |P|S|I| Reserved |E|T|a|R|M| Record Count | 957 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 958 | Nonce . . . | 959 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 960 | . . . Nonce | 961 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 962 | Key ID | Algorithm ID | Authentication Data Length | 963 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 964 ~ Authentication Data ~ 965 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 966 | | Record TTL | 967 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 968 R | Locator Count | EID mask-len | ACT |A| Reserved | 969 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 970 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 971 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 972 r | EID-Prefix | 973 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 974 | /| Priority | Weight | M Priority | M Weight | 975 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 976 | o | Unused Flags |L|p|R| Loc-AFI | 977 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 978 | \| Locator | 979 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 981 Packet field descriptions: 983 Type: 3 (Map-Register) 985 P: This is the proxy Map-Reply bit. When set to 1, the ETR sending 986 the Map-Register message is requesting the Map-Server to proxy a 987 Map-Reply. The Map-Server will send non-authoritative Map-Replies 988 on behalf of the ETR. 990 S: This is the security-capable bit. When set, the procedures from 991 [I-D.ietf-lisp-sec] are supported. 993 I: This is the ID-present bit. This bit is set to 1 to indicate that 994 a 128 bit xTR-ID and a 64 bit Site-ID fields are present at the 995 end of the Map-Register message. If an xTR is configured with an 996 xTR-ID and Site-ID, it MUST set the I bit to 1 and include its 997 xTR-ID and Site-ID in the Map-Register messages it generates. The 998 combination of Site-ID plus xTR-ID uniquely identifies an xTR in a 999 LISP domain and serves to track its last seen nonce. 1001 Reserved: This unassigned field MUST be set to 0 on transmit and 1002 MUST be ignored on receipt. 1004 E: This is the Map-Register EID-notify bit. This is used by a First- 1005 Hop-Router (FHR) which discovers a dynamic-EID. This EID-notify 1006 based Map-Register is sent by the FHR to a same site xTR that 1007 propogates the Map-Register to the mapping system. The site xTR 1008 keeps state to later Map-Notify the FHR after the EID has moves 1009 away. See [I-D.ietf-lisp-eid-mobility] for a detailed use-case. 1011 T: This is the use-TTL for timeout bit. When set to 1, the xTR wants 1012 the Map-Server to time out registrations based on the value in the 1013 "Record TTL" field of this message. Otherwise, the default 1014 timeout described in Section 8.2 is used. 1016 a: This is the merge-request bit. When set to 1, the xTR requests to 1017 merge RLOC-records from different xTRs registering the same EID- 1018 record. See signal-free multicast [RFC8378] for one use case 1019 example. 1021 R: This reserved and unassigned bit MUST be set to 0 on transmit and 1022 MUST be ignored on receipt. 1024 M: This is the want-map-notify bit. When set to 1, an ETR is 1025 requesting a Map-Notify message to be returned in response to 1026 sending a Map-Register message. The Map-Notify message sent by a 1027 Map-Server is used to acknowledge receipt of a Map-Register 1028 message. 1030 Record Count: This is the number of records in this Map-Register 1031 message. A record is comprised of that portion of the packet 1032 labeled 'Record' above and occurs the number of times equal to 1033 Record Count. 1035 Nonce: This 8-octet 'Nonce' field is incremented each time a Map- 1036 Register message is sent. When a Map-Register acknowledgement is 1037 requested, the nonce is returned by Map-Servers in Map-Notify 1038 messages. Since the entire Map-Register message is authenticated, 1039 the 'Nonce' field serves to protect against Map-Register replay 1040 attacks. An ETR that registers to the mapping system SHOULD store 1041 the last nonce sent in persistent storage so when it restarts it 1042 can continue using an incrementing nonce. If the ETR cannot 1043 support saving the nonce, then when it restarts it MUST use a new 1044 authentication key to register to the mapping system. A Map- 1045 Server MUST track and save in persistent storage the last nonce 1046 received for each ETR xTR-ID and key pair. If a Map-Register is 1047 received with a nonce value that is not greater than the saved 1048 nonce, it MUST drop the Map-Register message and SHOULD log the 1049 fact a replay attack could have occurred. 1051 Key ID: A key-id value that identifies a pre-shared secret between 1052 an ETR and a Map-Server. Per-message keys are derived from the 1053 pre-shared secret to authenticate the origin and protect the 1054 integrity of the Map-Register. The Key ID allows to rotate 1055 between multiple pre-shared secrets in a non disruptive way. The 1056 pre-shared secret MUST be unique per each LISP "Site-ID" 1058 Algorithm ID: This field identifies the Key Derivation Function 1059 (KDF) and Message Authentication Code (MAC) algorithms used to 1060 derive the key and to compute the Authentication Data of a Map- 1061 Register. This 8-bit field identifies the KDF and MAC algorithm 1062 pair. See Section 12.5 for codepoint assignments. 1064 Authentication Data Length: This is the length in octets of the 1065 'Authentication Data' field that follows this field. The length 1066 of the 'Authentication Data' field is dependent on the MAC 1067 algorithm used. The length field allows a device that doesn't 1068 know the MAC algorithm to correctly parse the packet. 1070 Authentication Data: This is the output of the MAC algorithm placed 1071 in this field after the MAC computation. The MAC output is 1072 computed as follows: 1074 1: The KDF algorithm is identified by the field 'Algorithm ID' 1075 according to the table in Section 12.5. Implementations of 1076 this specification MUST implement HMAC-SHA-256-128 [RFC4868] 1077 and SHOULD implement HMAC-SHA-256-128+HKDF-SHA256 [RFC5869] . 1079 2: The MAC algorithm is identified by the field 'Algorithm ID' 1080 according to the table in Section 12.5. 1082 3: The pre-shared secret used to derive the per-message key is 1083 represented by PSK[Key ID], that is the pre-shared secret 1084 identified by the 'Key ID'. 1086 4: The derived per-message key is computed as: per-msg- 1087 key=KDF(nonce+PSK[Key ID],s). Where the nonce is the value in 1088 the Nonce field of the Map-Register, '+' denotes concatenation 1089 and 's' (the salt) is a string that corresponds to the message 1090 type being authenticated. For Map-Register messages, it is 1091 equal to "Map-Register Authentication". Similarly, for Map- 1092 Notify and Map-Notify-Ack messages, it is "Map-Notify 1093 Authentication" and "Map-Notify-Ack Authentication", 1094 respectively. For those Algorithm IDs defined in Section 12.5 1095 that specify a 'none' KDF, the per-message key is computed as: 1096 per-msg-key = PSK[Key ID]. This means that the same key is 1097 used across multiple protocol messages. 1099 5: The MAC output is computed using the MAC algorithm and the 1100 per-msg-key over the entire Map-Register payload (from and 1101 including the LISP message type field through the end of the 1102 last RLOC record) with the authenticated data field preset to 1103 0. 1105 The definition of the rest of the Map-Register can be found in EID- 1106 record description in Section 5.4. When the I-bit is set, the 1107 following fields are added to the end of the Map-Register message: 1109 xTR-ID: xTR-ID is a 128 bit field at the end of the Map-Register 1110 message, starting after the final Record in the message. The xTR- 1111 ID is used to uniquely identify a xTR. The same xTR-ID value MUST 1112 NOT be used in two different xTRs in the scope of the Site-ID. 1114 Site-ID: Site-ID is a 64 bit field at the end of the Map- Register 1115 message, following the xTR-ID. Site-ID is used to uniquely 1116 identify to which site the xTR that sent the message belongs. 1117 This document does not specify a strict meaning for the Site-ID 1118 field. Informally it provides an indication that a group of xTRs 1119 have some relation, either administratively, topologically or 1120 otherwise. 1122 5.7. Map-Notify/Map-Notify-Ack Message Format 1124 This section specifies the encoding format for the Map-Notify and 1125 Map-Notify-Ack messages. The messages are sent inside a UDP packet 1126 with source and destination UDP ports equal to 4342. 1128 The Map-Notify and Map-Notify-Ack message formats are: 1130 0 1 2 3 1131 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 1132 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1133 |Type=4/5| Reserved | Record Count | 1134 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1135 | Nonce . . . | 1136 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1137 | . . . Nonce | 1138 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1139 | Key ID | Algorithm ID | Authentication Data Length | 1140 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1141 ~ Authentication Data ~ 1142 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1143 | | Record TTL | 1144 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1145 R | Locator Count | EID mask-len | ACT |A| Reserved | 1146 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1147 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 1148 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1149 r | EID-Prefix | 1150 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1151 | /| Priority | Weight | M Priority | M Weight | 1152 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1153 | o | Unused Flags |L|p|R| Loc-AFI | 1154 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1155 | \| Locator | 1156 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1158 Packet field descriptions: 1160 Type: 4/5 (Map-Notify/Map-Notify-Ack) 1162 The Map-Notify message has the same contents as a Map-Register 1163 message. See the Map-Register section for field descriptions and the 1164 Map-Reply section for EID-record and RLOC-record descriptions. 1166 The fields of the Map-Notify are copied from the corresponding Map- 1167 Register to acknowledge its correct processing. In the Map-Notfiy, 1168 the 'Authentication Data' field is recomputed using the corresponding 1169 per-message key and according to the procedure defined in the 1170 previous section. The Map-Notify message can also used, outside the 1171 scope of this specification, in an unsolicited manner, such as is 1172 specified in [I-D.ietf-lisp-pubsub]. 1174 After sending a Map-Register, if a Map-Notify is not received after 1 1175 second the transmitter MUST re-transmit the original Map-Register 1176 with an exponential backoff (base of 2, that is, the next backoff 1177 timeout interval is doubled), the maximum backoff is 1 minute. Map- 1178 Notify messages are only transmitted upon the reception of a Map- 1179 Register with the M-bit set, Map-Notify messages are not 1180 retransmitted. The only exeption to this is for unsolicited Map- 1181 Notify messages, see below. 1183 A Map-Server sends an unsolicited Map-Notify message (one that is not 1184 used as an acknowledgment to a Map-Register message) only in 1185 conformance with the Congestion Control And Relability Guideline 1186 sections of [RFC8085]. A Map-Notify is retransmitted until a Map- 1187 Notify-Ack is received by the Map-Server with the same nonce used in 1188 the Map-Notify message. An implementation SHOULD retransmit up to 3 1189 times at 3 second retransmission intervals, after which time the 1190 retransmission interval is exponentially backed-off (base of 2, that 1191 is, the next backoff timeout interval is doubled) for another 3 1192 retransmission attempts. Map-Notify-Ack messages are only 1193 transmitted upon the reception of an unsolicited Map-Notify, Map- 1194 Notify-Ack messages are not retransmitted. 1196 The Map-Notify-Ack message has the same contents as a Map-Notify 1197 message. It is used to acknowledge the receipt of an unsolicited 1198 Map-Notify and, once the the authentication data is validated, allows 1199 for the sender to stop retransmitting a Map-Notify with the same 1200 nonce and the authentication data validates. The fields of the Map- 1201 Notify-Ack are copied from the corresponding Map-Notify message to 1202 acknowledge its correct processing. The 'Authentication Data' field 1203 is recomputed using the corresponding per-message key and according 1204 to the procedure defined in the previous section. 1206 Upon reception of Map-Register, Map-Notify or Map-Notifiy-Ack, the 1207 receiver verifies the authentication data. If the authentication 1208 data fails to validate, the message is dropped without further 1209 processing. 1211 5.8. Encapsulated Control Message Format 1213 An Encapsulated Control Message (ECM) is used to encapsulate control 1214 packets sent between xTRs and the mapping database system or internal 1215 to the mapping database system. 1217 0 1 2 3 1218 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 1219 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1220 / | IPv4 or IPv6 Header | 1221 OH | (uses RLOC addresses) | 1222 \ | | 1223 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1224 / | Source Port = xxxx | Dest Port = 4342 | 1225 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1226 \ | UDP Length | UDP Checksum | 1227 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1228 LISP |Type=8 |S|D|R|R| Reserved | 1229 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1230 / | IPv4 or IPv6 Header | 1231 IH | (uses RLOC or EID addresses) | 1232 \ | | 1233 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1234 / | Source Port = xxxx | Dest Port = yyyy | 1235 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1236 \ | UDP Length | UDP Checksum | 1237 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1238 LCM | LISP Control Message | 1239 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1241 Packet header descriptions: 1243 OH: The outer IPv4 or IPv6 header, which uses RLOC addresses in the 1244 source and destination header address fields. 1246 UDP: The outer UDP header with destination port 4342. The source 1247 port is randomly allocated. The checksum field MUST be non- 1248 zero. 1250 LISP: Type 8 is defined to be a "LISP Encapsulated Control Message", 1251 and what follows is either an IPv4 or IPv6 header as encoded by 1252 the first 4 bits after the 'Reserved' field, or the 1253 Authentication Data field [I-D.ietf-lisp-sec] if the S-bit (see 1254 below) is set. 1256 Type: 8 (Encapsulated Control Message (ECM)) 1257 S: This is the Security bit. When set to 1, the field following 1258 the 'Reserved' field will have the following Authentication 1259 Data format and follow the procedures from [I-D.ietf-lisp-sec]. 1261 0 1 2 3 1262 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 1263 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1264 | AD Type | Authentication Data Content . . . | 1265 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1267 D: This is the DDT-bit. When set to 1, the sender is requesting a 1268 Map-Referral message to be returned. The details of this 1269 procedure are described in [RFC8111]. 1271 R: This reserved and unassigned bit MUST be set to 0 on transmit 1272 and MUST be ignored on receipt. 1274 IH: The inner IPv4 or IPv6 header, which can use either RLOC or EID 1275 addresses in the header address fields. When a Map-Request is 1276 encapsulated in this packet format, the destination address in 1277 this header is an EID. 1279 UDP: The inner UDP header, where the port assignments depend on the 1280 control packet being encapsulated. When the control packet is 1281 a Map-Request or Map-Register, the source port is selected by 1282 the ITR/PITR and the destination port is 4342. When the 1283 control packet is a Map-Reply, the source port is 4342 and the 1284 destination port is assigned from the source port of the 1285 invoking Map-Request. Port number 4341 MUST NOT be assigned to 1286 either port. The checksum field MUST be non-zero. 1288 LCM: The format is one of the control message formats described in 1289 Section 5. Map-Request messages are allowed to be Control- 1290 Plane (ECM) encapsulated. When Map-Requests are sent for RLOC- 1291 Probing purposes (i.e. the probe-bit is set), they MUST NOT be 1292 sent inside Encapsulated Control Messages. PIM Join/Prune 1293 messages [RFC6831] are also allowed to be Control-Plane (ECM) 1294 encapsulated. 1296 6. Changing the Contents of EID-to-RLOC Mappings 1298 In the LISP architecture ITRs/PITRs use a local Map-Cache to store 1299 EID-to-RLOC mappings for forwarding. When an ETR updates a mapping a 1300 mechanism is required to inform ITRs/PITRs that are using such 1301 mappings. 1303 The LISP Data-Plane defines several mechanism to update mappings 1304 [I-D.ietf-lisp-rfc6830bis]. This document specifies the Solicit-Map 1305 Request (SMR), a Control-Plane push-based mechanism. An additional 1306 Control-Plane mechanism based on the Publish/subscribe paradigm is 1307 specified in [I-D.ietf-lisp-pubsub]. 1309 6.1. Solicit-Map-Request (SMR) 1311 Soliciting a Map-Request is a selective way for ETRs, at the site 1312 where mappings change, to control the rate they receive requests for 1313 Map-Reply messages. SMRs are also used to tell remote ITRs to update 1314 the mappings they have cached. 1316 Since ETRs are not required to keep track of remote ITRs that have 1317 cached their mappings, they do not know which ITRs need to have their 1318 mappings updated. As a result, an ETR will solicit Map-Requests to 1319 those sites to which it has been sending LISP encapsulated data 1320 packets for the last minute. As a result, when an ETR is also acting 1321 as ITR, it will send an SMR to an ITR to which it has recently sent 1322 encapsulated data. 1324 An SMR message is simply a bit set in a Map-Request message. An ITR 1325 or PITR will send a Map-Request (SMR-invoked Map-Request) when they 1326 receive an SMR message. While the SMR message is sent through the 1327 data-plane, the SMR-invoked Map-Request MUST be sent through the 1328 Mapping System (not directly). 1330 Both the SMR sender and the SMR responder MUST rate-limit these 1331 messages. It is RECOMMENDED that the SMR sender rate-limits Map- 1332 Request for the same destination RLOC to no more than one packet per 1333 3 seconds. It is RECOMMENDED that the SMR responder rate-limits Map- 1334 Request for the same EID-Prefix to no more than once per 3 seconds. 1336 When an ITR receives an SMR message for which it does not have a 1337 cached mapping for the EID in the SMR message, it SHOULD NOT send an 1338 SMR-invoked Map-Request. This scenario can occur when an ETR sends 1339 SMR messages to all Locators in the Locator-Set it has stored in its 1340 Map-Cache but the remote ITRs that receive the SMR may not be sending 1341 packets to the site. There is no point in updating the ITRs until 1342 they need to send, in which case they will send Map-Requests to 1343 obtain a Map-Cache entry. 1345 7. Routing Locator Reachability 1347 This document defines several Control-Plane mechanisms for 1348 determining RLOC reachability. Please note that additional Data- 1349 Plane reachability mechanisms are defined in 1350 [I-D.ietf-lisp-rfc6830bis]. 1352 1. An ITR may receive an ICMP Network Unreachable or Host 1353 Unreachable message for an RLOC it is using. This indicates that 1354 the RLOC is likely down. Note that trusting ICMP messages may 1355 not be desirable, but neither is ignoring them completely. 1356 Implementations are encouraged to follow current best practices 1357 in treating these conditions [I-D.ietf-opsec-icmp-filtering]. 1359 2. When an ITR participates in the routing protocol that operates in 1360 the underlay routing system, it can determine that an RLOC is 1361 down when no Routing Information Base (RIB) entry exists that 1362 matches the RLOC IP address. 1364 3. An ITR may receive an ICMP Port Unreachable message from a 1365 destination host. This occurs if an ITR attempts to use 1366 interworking [RFC6832] and LISP-encapsulated data is sent to a 1367 non-LISP-capable site. 1369 4. An ITR may receive a Map-Reply from an ETR in response to a 1370 previously sent Map-Request. The RLOC source of the Map-Reply is 1371 likely up, since the ETR was able to send the Map-Reply to the 1372 ITR. Please note that in some scenarios the RLOC -from the outer 1373 header- can be an spoofable field. 1375 5. An ITR/ETR pair can use the 'RLOC-Probing' mechanism described 1376 below. 1378 When ITRs receive ICMP Network Unreachable or Host Unreachable 1379 messages as a method to determine unreachability, they will refrain 1380 from using Locators that are described in Locator lists of Map- 1381 Replies. However, using this approach is unreliable because many 1382 network operators turn off generation of ICMP Destination Unreachable 1383 messages. 1385 If an ITR does receive an ICMP Network Unreachable or Host 1386 Unreachable message, it MAY originate its own ICMP Destination 1387 Unreachable message destined for the host that originated the data 1388 packet the ITR encapsulated. 1390 This assumption does create a dependency: Locator unreachability is 1391 detected by the receipt of ICMP Host Unreachable messages. When a 1392 Locator has been determined to be unreachable, it is not used for 1393 active traffic; this is the same as if it were listed in a Map-Reply 1394 with Priority 255. 1396 The ITR can test the reachability of the unreachable Locator by 1397 sending periodic Map-Requests. Both Map-Requests and Map-Replies 1398 MUST be rate-limited, see Section 5.3 and Section 5.4 for information 1399 about rate-limiting. Locator reachability testing is never done with 1400 data packets, since that increases the risk of packet loss for end- 1401 to-end sessions. 1403 7.1. RLOC-Probing Algorithm 1405 RLOC-Probing is a method that an ITR or PITR can use to determine the 1406 reachability status of one or more Locators that it has cached in a 1407 Map-Cache entry. The probe-bit of the Map-Request and Map-Reply 1408 messages is used for RLOC-Probing. 1410 RLOC-Probing is done in the control plane on a timer basis, where an 1411 ITR or PITR will originate a Map-Request destined to a locator 1412 address from one of its own locator addresses. A Map-Request used as 1413 an RLOC-probe is NOT encapsulated and NOT sent to a Map-Server or to 1414 the mapping database system as one would when requesting mapping 1415 data. The EID record encoded in the Map-Request is the EID-Prefix of 1416 the Map-Cache entry cached by the ITR or PITR. The ITR MAY include a 1417 mapping data record for its own database mapping information that 1418 contains the local EID-Prefixes and RLOCs for its site. RLOC-probes 1419 are sent periodically using a jittered timer interval. 1421 When an ETR receives a Map-Request message with the probe-bit set, it 1422 returns a Map-Reply with the probe-bit set. The source address of 1423 the Map-Reply is set to the IP address of the outgoing interface the 1424 Map-Reply destination address routes to. The Map-Reply SHOULD 1425 contain mapping data for the EID-Prefix contained in the Map-Request. 1426 This provides the opportunity for the ITR or PITR that sent the RLOC- 1427 probe to get mapping updates if there were changes to the ETR's 1428 database mapping entries. 1430 There are advantages and disadvantages of RLOC-Probing. The main 1431 benefit of RLOC-Probing is that it can handle many failure scenarios 1432 allowing the ITR to determine when the path to a specific Locator is 1433 reachable or has become unreachable, thus providing a robust 1434 mechanism for switching to using another Locator from the cached 1435 Locator. RLOC-Probing can also provide rough Round-Trip Time (RTT) 1436 estimates between a pair of Locators, which can be useful for network 1437 management purposes as well as for selecting low delay paths. The 1438 major disadvantage of RLOC-Probing is in the number of control 1439 messages required and the amount of bandwidth used to obtain those 1440 benefits, especially if the requirement for failure detection times 1441 is very small. 1443 8. Interactions with Other LISP Components 1445 8.1. ITR EID-to-RLOC Mapping Resolution 1447 An ITR is configured with one or more Map-Resolver addresses. These 1448 addresses are "Locators" (or RLOCs) and MUST be routable on the 1449 underlying core network; they MUST NOT need to be resolved through 1450 LISP EID-to-RLOC mapping, as that would introduce a circular 1451 dependency. When using a Map-Resolver, an ITR does not need to 1452 connect to any other database mapping system. 1454 An ITR sends an Encapsulated Map-Request to a configured Map-Resolver 1455 when it needs an EID-to-RLOC mapping that is not found in its local 1456 Map-Cache. Using the Map-Resolver greatly reduces both the 1457 complexity of the ITR implementation and the costs associated with 1458 its operation. 1460 In response to an Encapsulated Map-Request, the ITR can expect one of 1461 the following: 1463 o An immediate Negative Map-Reply (with action code of "Natively- 1464 Forward", 15-minute Time to Live (TTL)) from the Map-Resolver if 1465 the Map-Resolver can determine that the requested EID does not 1466 exist. The ITR saves the EID-Prefix returned in the Map-Reply in 1467 its cache, marks it as non-LISP-capable, and knows not to attempt 1468 LISP encapsulation for destinations matching it. 1470 o A Negative Map-Reply, with action code of "Natively-Forward", from 1471 a Map-Server that is authoritative (within the LISP deployment 1472 Section 1.1) for an EID-Prefix that matches the requested EID but 1473 that does not have an actively registered, more-specific EID- 1474 prefix. In this case, the requested EID is said to match a "hole" 1475 in the authoritative EID-Prefix. If the requested EID matches a 1476 more-specific EID-Prefix that has been delegated by the Map-Server 1477 but for which no ETRs are currently registered, a 1-minute TTL is 1478 returned. If the requested EID matches a non-delegated part of 1479 the authoritative EID-Prefix, then it is not a LISP EID and a 1480 15-minute TTL is returned. See Section 8.2 for discussion of 1481 aggregate EID-Prefixes and details of Map-Server EID-Prefix 1482 matching. 1484 o A LISP Map-Reply from the ETR that owns the EID-to-RLOC mapping or 1485 possibly from a Map-Server answering on behalf of the ETR. See 1486 Section 8.4 for more details on Map-Resolver message processing. 1488 Note that an ITR may be configured to both use a Map-Resolver and to 1489 participate in a LISP-ALT logical network. In such a situation, the 1490 ITR SHOULD send Map-Requests through the ALT network for any EID- 1491 Prefix learned via ALT BGP. Such a configuration is expected to be 1492 very rare, since there is little benefit to using a Map-Resolver if 1493 an ITR is already using LISP-ALT. There would be, for example, no 1494 need for such an ITR to send a Map-Request to a possibly non-existent 1495 EID (and rely on Negative Map-Replies) if it can consult the ALT 1496 database to verify that an EID-Prefix is present before sending that 1497 Map-Request. 1499 8.2. EID-Prefix Configuration and ETR Registration 1501 An ETR publishes its EID-Prefixes on a Map-Server by sending LISP 1502 Map-Register messages. A Map-Register message includes 1503 authentication data, so prior to sending a Map-Register message, the 1504 ETR and Map-Server MUST be configured with a pre-shared secret used 1505 to derive Map-Register authentication keys. A Map-Server's 1506 configuration SHOULD also include a list of the EID-Prefixes for 1507 which each ETR is authoritative. Upon receipt of a Map-Register from 1508 an ETR, a Map-Server accepts only EID-Prefixes that are configured 1509 for that ETR. Failure to implement such a check would leave the 1510 mapping system vulnerable to trivial EID-Prefix hijacking attacks. 1512 In addition to the set of EID-Prefixes defined for each ETR that may 1513 register, a Map-Server is typically also configured with one or more 1514 aggregate prefixes that define the part of the EID numbering space 1515 assigned to it. When LISP-ALT is the database in use, aggregate EID- 1516 Prefixes are implemented as discard routes and advertised into ALT 1517 BGP. The existence of aggregate EID-Prefixes in a Map-Server's 1518 database means that it may receive Map Requests for EID-Prefixes that 1519 match an aggregate but do not match a registered prefix; Section 8.3 1520 describes how this is handled. 1522 Map-Register messages are sent periodically from an ETR to a Map- 1523 Server with a suggested interval between messages of one minute. A 1524 Map-Server SHOULD time out and remove an ETR's registration if it has 1525 not received a valid Map-Register message within the past 1526 three minutes. When first contacting a Map-Server after restart or 1527 changes to its EID-to-RLOC database mappings, an ETR MAY initially 1528 send Map-Register messages at an increased frequency, up to one every 1529 20 seconds. This "quick registration" period is limited to 1530 five minutes in duration. 1532 An ETR MAY request that a Map-Server explicitly acknowledge receipt 1533 and processing of a Map-Register message by setting the "want-map- 1534 notify" (M-bit) flag. A Map-Server that receives a Map-Register with 1535 this flag set will respond with a Map-Notify message. Typical use of 1536 this flag by an ETR would be to set it for Map-Register messages sent 1537 during the initial "quick registration" with a Map-Server but then 1538 set it only occasionally during steady-state maintenance of its 1539 association with that Map-Server. Note that the Map-Notify message 1540 is sent to UDP destination port 4342, not to the source port 1541 specified in the original Map-Register message. 1543 Note that a one-minute minimum registration interval during 1544 maintenance of an ETR-Map-Server association places a lower bound on 1545 how quickly and how frequently a mapping database entry can be 1546 updated. This may have implications for what sorts of mobility can 1547 be supported directly by the mapping system; shorter registration 1548 intervals or other mechanisms might be needed to support faster 1549 mobility in some cases. For a discussion on one way that faster 1550 mobility may be implemented for individual devices, please see 1551 [I-D.ietf-lisp-mn]. 1553 An ETR MAY also request, by setting the "proxy Map-Reply" flag 1554 (P-bit) in the Map-Register message, that a Map-Server answer Map- 1555 Requests instead of forwarding them to the ETR. See Section 7.1 for 1556 details on how the Map-Server sets certain flags (such as those 1557 indicating whether the message is authoritative and how returned 1558 Locators SHOULD be treated) when sending a Map-Reply on behalf of an 1559 ETR. When an ETR requests proxy reply service, it SHOULD include all 1560 RLOCs for all ETRs for the EID-Prefix being registered, along with 1561 the routable flag ("R-bit") setting for each RLOC. The Map-Server 1562 includes all of this information in Map-Reply messages that it sends 1563 on behalf of the ETR. This differs from a non-proxy registration, 1564 since the latter need only provide one or more RLOCs for a Map-Server 1565 to use for forwarding Map-Requests; the registration information is 1566 not used in Map-Replies, so it being incomplete is not incorrect. 1568 An ETR that uses a Map-Server to publish its EID-to-RLOC mappings 1569 does not need to participate further in the mapping database 1570 protocol(s). When using a LISP-ALT mapping database, for example, 1571 this means that the ETR does not need to implement GRE or BGP, which 1572 greatly simplifies its configuration and reduces its cost of 1573 operation. 1575 Note that use of a Map-Server does not preclude an ETR from also 1576 connecting to the mapping database (i.e., it could also connect to 1577 the LISP-ALT network), but doing so doesn't seem particularly useful, 1578 as the whole purpose of using a Map-Server is to avoid the complexity 1579 of the mapping database protocols. 1581 8.3. Map-Server Processing 1583 Once a Map-Server has EID-Prefixes registered by its client ETRs, it 1584 can accept and process Map-Requests for them. 1586 In response to a Map-Request, the Map-Server first checks to see if 1587 the destination EID matches a configured EID-Prefix. If there is no 1588 match, the Map-Server returns a Negative Map-Reply with action code 1589 "Natively-Forward" and a 15-minute TTL. This can occur if a Map 1590 Request is received for a configured aggregate EID-Prefix for which 1591 no more-specific EID-Prefix exists; it indicates the presence of a 1592 non-LISP "hole" in the aggregate EID-Prefix. 1594 Next, the Map-Server checks to see if any ETRs have registered the 1595 matching EID-Prefix. If none are found, then the Map-Server returns 1596 a Negative Map-Reply with action code "Natively-Forward" and a 1597 1-minute TTL. 1599 If the EID-prefix is either registered or not registered to the 1600 mapping system and there is a policy in the Map-Server to have the 1601 requestor drop packets for the matching EID-prefix, then a Drop/ 1602 Policy-Denied action is returned. If the EID-prefix is registered or 1603 not registered and there is a authentication failure, then a Drop/ 1604 Authentication- failure action is returned. If either of these 1605 actions result as a temporary state in policy or authentication then 1606 a Send-Map-Request action with 1-minute TTL MAY be returned to allow 1607 the requestor to retry the Map-Request. 1609 If any of the registered ETRs for the EID-Prefix have requested proxy 1610 reply service, then the Map-Server answers the request instead of 1611 forwarding it. It returns a Map-Reply with the EID-Prefix, RLOCs, 1612 and other information learned through the registration process. 1614 If none of the ETRs have requested proxy reply service, then the Map- 1615 Server re-encapsulates and forwards the resulting Encapsulated Map- 1616 Request to one of the registered ETRs. It does not otherwise alter 1617 the Map-Request, so any Map-Reply sent by the ETR is returned to the 1618 RLOC in the Map-Request, not to the Map-Server. Unless also acting 1619 as a Map-Resolver, a Map-Server should never receive Map-Replies; any 1620 such messages SHOULD be discarded without response, perhaps 1621 accompanied by the logging of a diagnostic message if the rate of 1622 Map-Replies is suggestive of malicious traffic. 1624 8.4. Map-Resolver Processing 1626 Upon receipt of an Encapsulated Map-Request, a Map-Resolver 1627 decapsulates the enclosed message and then searches for the requested 1628 EID in its local database of mapping entries (statically configured 1629 or learned from associated ETRs if the Map-Resolver is also a Map- 1630 Server offering proxy reply service). If it finds a matching entry, 1631 it returns a LISP Map-Reply with the known mapping. 1633 If the Map-Resolver does not have the mapping entry and if it can 1634 determine that the EID is not in the mapping database (for example, 1635 if LISP-ALT is used, the Map-Resolver will have an ALT forwarding 1636 table that covers the full EID space), it immediately returns a 1637 negative LISP Map-Reply, with action code "Natively-Forward" and a 1638 15-minute TTL. To minimize the number of negative cache entries 1639 needed by an ITR, the Map-Resolver SHOULD return the least-specific 1640 prefix that both matches the original query and does not match any 1641 EID-Prefix known to exist in the LISP-capable infrastructure. 1643 If the Map-Resolver does not have sufficient information to know 1644 whether the EID exists, it needs to forward the Map-Request to 1645 another device that has more information about the EID being 1646 requested. To do this, it forwards the unencapsulated Map-Request, 1647 with the original ITR RLOC as the source, to the mapping database 1648 system. Using LISP-ALT, the Map-Resolver is connected to the ALT 1649 network and sends the Map-Request to the next ALT hop learned from 1650 its ALT BGP neighbors. The Map-Resolver does not send any response 1651 to the ITR; since the source RLOC is that of the ITR, the ETR or Map- 1652 Server that receives the Map-Request over the ALT and responds will 1653 do so directly to the ITR. 1655 8.4.1. Anycast Operation 1657 A Map-Resolver can be set up to use "anycast", where the same address 1658 is assigned to multiple Map-Resolvers and is propagated through IGP 1659 routing, to facilitate the use of a topologically close Map-Resolver 1660 by each ITR. 1662 ETRs MAY have anycast RLOC addresses which are registered as part of 1663 their RLOC-set to the mapping system. However, registrations MUST 1664 use their unique RLOC addresses, distinct authentication keys or 1665 different XTR-IDs to identify security associations with the Map- 1666 Servers. 1668 9. Security Considerations 1670 A LISP threat analysis can be found in [RFC7835]. In what follows we 1671 highlight security considerations that apply when LISP is deployed in 1672 environments such as those specified in Section 1.1, where the 1673 following assumptions hold: 1675 1. The Mapping System is secure and trusted, and for the purpose of 1676 this security considerations the Mapping System is considered as 1677 one trusted element. 1679 2. The ETRs have a pre-configured trust relationship with the 1680 Mapping System, which includes some form of shared secret, and 1681 the Mapping System is aware of which EIDs an ETR can advertise. 1682 How those keys and mappings gets established is out of the scope 1683 of this document. 1685 3. LISP-SEC [I-D.ietf-lisp-sec] MUST be implemented. Network 1686 operators should carefully weight how the LISP-SEC threat model 1687 applies to their particular use case or deployment. If they 1688 decide to ignore a particular recommendation, they should make 1689 sure the risk associated with the corresponding threats is well 1690 understood. 1692 The Map-Request/Map-Reply message exchange can be exploited by an 1693 attacker to mount DoS and/or amplification attacks. Attackers can 1694 send Map-Requests at high rates to overload LISP nodes and increase 1695 the state maintained by such nodes or consume CPU cycles. Such 1696 threats can be mitigated by systematically applying filters and rate 1697 limiters. 1699 The Map-Request/Map-Reply message exchange can also be exploited to 1700 inject forged mappings directly in the ITR EID-to-RLOC map-cache. 1701 This can lead to traffic being redirected to the attacker, see 1702 further details in [RFC7835]. In addition, valid ETRs in the system 1703 can perform overclaiming attacks. In this case, attackers can claim 1704 to own an EID-prefix that is larger than the prefix owned by the ETR. 1705 Such attacks can be addressed by using LISP-SEC [I-D.ietf-lisp-sec]. 1706 The LISP-SEC protocol defines a mechanism for providing origin 1707 authentication, integrity protection, and prevention of 'man-in-the- 1708 middle' and 'prefix overclaiming' attacks on the Map-Request/Map- 1709 Reply exchange. In addition and while beyond the scope of securing 1710 an individual Map-Server or Map-Resolver, it should be noted that 1711 LISP-SEC can be complemented by additional security mechanisms 1712 defined by the Mapping System Infrastructure. For instance, BGP- 1713 based LISP-ALT [RFC6836] can take advantage of standards work on 1714 adding security to BGP while LISP-DDT [RFC8111] defines its own 1715 additional security mechanisms. 1717 To publish an authoritative EID-to-RLOC mapping with a Map-Server 1718 using the Map-Register message, an ETR includes authentication data 1719 that is a MAC of the entire message using a key derived from the pre- 1720 shared secret. An implementation SHOULD support HMAC-SHA256- 1721 128+HKDF-SHA256 [RFC5869]. The Map-Register message includes 1722 protection for replay attacks by a man-in-the-middle. However, there 1723 is a potential attack where a compromised ETR could overclaim the 1724 prefix it owns and successfully register it on its corresponding Map- 1725 Server. To mitigate this and as noted in Section 8.2, a Map-Server 1726 MUST verify that all EID-Prefixes registered by an ETR match the 1727 configuration stored on the Map-Server. 1729 Deployments concerned about manipulations of Map-Request and Map- 1730 Reply messages, and malicious ETR EID prefix overclaiming MUST drop 1731 LISP Control Plane messages that do not contain LISP-SEC material 1732 (S-bit, EID-AD, OTK-AD, PKT-AD). 1734 Mechanisms to encrypt, support privacy, prevent eavesdropping and 1735 packet tampering for messages exchanged between xTRs, xTRs and the 1736 mapping system, and nodes that make up the mapping system, SHOULD be 1737 deployed. Examples of this are DTLS [RFC6347] or LISP-crypto 1738 [RFC8061]. 1740 10. Privacy Considerations 1742 As noted by [RFC6973] privacy is a complex issue that greatly depends 1743 on the specific protocol use-case and deployment. As noted in 1744 section 1.1 of [I-D.ietf-lisp-rfc6830bis] LISP focuses on use-cases 1745 where entities communicate over the public Internet while keeping 1746 separate addressing and topology. In what follows we detail the 1747 privacy threats introduced by the LISP Control Plane, the analysis is 1748 based on the guidelines detailed in [RFC6973]. 1750 LISP can use long-lived identifiers (EIDs) that survive mobility 1751 events. Such identifiers bind to the RLOCs of the nodes, which 1752 represents the topological location with respect to the specific LISP 1753 deployments. In addition, EID-to-RLOC mappings are typically 1754 considered public information within the LISP deployment when 1755 control-plane messages are not encrypted, and can be eavesdropped 1756 while Map-Request messages are sent to the corresponding Map- 1757 Resolvers or Map-Register messages to Map-Servers. 1759 In this context, attackers can correlate the EID with the RLOC and 1760 track the corresponding user topological location and/or mobility. 1761 This can be achieved by off-path attackers, if they are 1762 authenticated, by querying the mapping system. Deployments concerned 1763 about this threat can use access control-lists or stronger 1764 authentication mechanisms [I-D.ietf-lisp-ecdsa-auth] in the mapping 1765 system to make sure that only authorized users can access this 1766 information (data minimization). Use of ephemeral EIDs 1767 [I-D.ietf-lisp-eid-anonymity] to achieve anonymity is another 1768 mechanism to lessen persistency and identity tracking. 1770 11. Changes since RFC 6833 1772 For implementation considerations, the following major changes have 1773 been made to this document since RFC 6833 was published: 1775 o A Map-Notify-Ack message is added in this document to provide 1776 reliability for Map-Notify messages. Any receiver of a Map-Notify 1777 message must respond with a Map-Notify-Ack message. Map-Servers 1778 who are senders of Map-Notify messages, must queue the Map-Notify 1779 contents until they receive a Map-Notify-Ack with the nonce used 1780 in the Map-Notify message. Note that implementations for Map- 1781 Notify-Ack support already exist and predate this document. 1783 o This document is incorporating the codepoint for the Map-Referral 1784 message from the LISP-DDT specification [RFC8111] to indicate that 1785 a Map-Server must send the final Map-Referral message when it 1786 participates in the LISP-DDT mapping system procedures. 1788 o The L" and "D" bits are added to the Map-Request message. See 1789 Section 5.3 for details. 1791 o The "S", "I", "E", "T", "a", "R", and "M" bits are added to the 1792 Map-Register message. See Section 5.6 for details. 1794 o The 16-bit Key-ID field of the Map-Register message has been split 1795 into a 8-bit Key-ID field and a 8-bit Algorithm-ID field. 1797 o The nonce and the authentication data in the Map-Register message 1798 have a different behaviour, see Section 5.6 for details. 1800 o This document adds two new Action values that are in an EID-record 1801 that appear in Map-Reply, Map-Register, Map-Notify, and Map- 1802 Notify-Ack messages. The Drop/Policy-Denied and Drop/Auth-Failure 1803 are the descriptions for the two new action values. See 1804 Section 5.4 for details. 1806 12. IANA Considerations 1808 This section provides guidance to the Internet Assigned Numbers 1809 Authority (IANA) regarding registration of values related to this 1810 LISP Control-Plane specification, in accordance with BCP 26 1811 [RFC8126]. 1813 There are three namespaces (listed in the sub-sections below) in LISP 1814 that have been registered. 1816 o LISP IANA registry allocations should not be made for purposes 1817 unrelated to LISP routing or transport protocols. 1819 o The following policies are used here with the meanings defined in 1820 BCP 26: "Specification Required", "IETF Review", "Experimental 1821 Use", and "First Come First Served". 1823 12.1. LISP UDP Port Numbers 1825 The IANA registry has allocated UDP port number 4342 for the LISP 1826 Control-Plane. IANA has updated the description for UDP port 4342 as 1827 follows: 1829 Keyword Port Transport Layer Description 1830 ------- ---- --------------- ----------- 1831 lisp-control 4342 udp LISP Control Packets 1833 12.2. LISP Packet Type Codes 1835 It is being requested that the IANA be authoritative for LISP Packet 1836 Type definitions and it is requested to replace the [RFC6830] 1837 registry message references with the RFC number assigned to this 1838 document. 1840 Based on deployment experience of [RFC6830], the Map-Notify-Ack 1841 message, message type 5, was added by this document. This document 1842 requests IANA to add it to the LISP Packet Type Registry. 1844 Name Number Defined in 1845 ---- ------ ----------- 1846 LISP Map-Notify-Ack 5 RFC6833bis 1848 12.3. LISP Map-Reply EID-Record Action Codes 1850 New ACT values can be allocated through IETF review or IESG approval. 1851 Four values have already been allocated by [RFC6830]. IANA is 1852 requested to replace the [RFC6830] reference for this registry with 1853 the RFC number assigned to this document and [RFC6830]. This 1854 specification changes the name of ACT type 3 value from "Drop" to 1855 "Drop/No-Reason" as well as adding two new ACT values, the "Drop/ 1856 Policy-Denied" (type 4) and "Drop/Authentication-Failure" (type 5). 1858 +-------+--------------------+-------------------------+------------+ 1859 | Value | Action | Description | Raeference | 1860 +-------+--------------------+-------------------------+------------+ 1861 | 4 | Drop/Policy-Denied | A packet matching this | RFC6833bis | 1862 | | | Map-Cache entry is | | 1863 | | | dropped because the | | 1864 | | | target EWID is policy- | | 1865 | | | denied by the xTR or | | 1866 | | | the mapping system. | | 1867 | 5 | Drop/Auth-Failure | Packet matching the | RFC6833bis | 1868 | | | Map-Cache entry is | | 1869 | | | dropped beacuse the | | 1870 | | | Map-Request for the | | 1871 | | | target EID fails an | | 1872 | | | authentication check by | | 1873 | | | the xTR or the mapping | | 1874 | | | system. | | 1875 +-------+--------------------+-------------------------+------------+ 1877 LISP Map-Reply Action Values 1879 In addition, LISP has a number of flag fields and reserved fields, 1880 such as the LISP header flags field [I-D.ietf-lisp-rfc6830bis]. New 1881 bits for flags in these fields can be implemented after IETF review 1882 or IESG approval, but these need not be managed by IANA. 1884 12.4. LISP Address Type Codes 1886 LISP Canonical Address Format (LCAF) [RFC8060] is an 8-bit field that 1887 defines LISP-specific encodings for AFI value 16387. LCAF encodings 1888 are used for specific use-cases where different address types for 1889 EID-records and RLOC-records are required. 1891 The IANA registry "LISP Canonical Address Format (LCAF) Types" is 1892 used for LCAF types. The registry for LCAF types use the 1893 Specification Required policy [RFC8126]. Initial values for the 1894 registry as well as further information can be found in [RFC8060]. 1896 Therefore, there is no longer a need for the "LISP Address Type 1897 Codes" registry requested by [RFC6830]. This document requests to 1898 remove it. 1900 12.5. LISP Algorithm ID Numbers 1902 In [RFC6830], a request for a "LISP Key ID Numbers" registry was 1903 submitted. This document renames the registry to "LISP Algorithm ID 1904 Numbers" and requests the IANA to make the name change. 1906 The following Algorithm ID values are defined by this specification 1907 as used in any packet type that references a 'Algorithm ID' field: 1909 Name Number MAC KDF 1910 ------------------------------------------------------- 1911 None 0 None None 1912 HMAC-SHA-1-96-None 1 [RFC2404] None 1913 HMAC-SHA-256-128-None 2 [RFC4868] None 1914 HMAC-SHA256-128+HKDF-SHA256 3 [RFC4868] [RFC4868] 1916 Number values are in the range of 0 to 255. The allocation of values 1917 is on a first come first served basis. 1919 12.6. LISP Bit Flags 1921 This document asks IANA to create a registry for allocation of bits 1922 in several headers of the LISP control plane, namely in the Map- 1923 Request, Map-Reply, Map-Register, Encapsulated Control Message (ECM) 1924 messages. Bit allocations are also requested for EID-records and 1925 RLOC-records. The registry created should be named "LISP Control 1926 Plane Header Bits". A sub-registry needs to be created per each 1927 message and EID-record. The name of each sub-registry is indicated 1928 below, along with its format and allocation of bits defined in this 1929 document. Any additional bits allocation, requires a specification, 1930 according with [RFC8126] policies. 1932 Sub-Registry: Map-Request Header Bits [Section 5.2]: 1934 0 1 2 3 1935 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 1936 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1937 |Type=1 |A|M|P|S|p|s|R|R| Rsvd |L|D| IRC | Record Count | 1938 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1939 +----------+---------------+------------+---------------------------+ 1940 | Spec | IANA Name | Bit | Description | 1941 | Name | | Position | | 1942 +----------+---------------+------------+---------------------------+ 1943 | A | map-request-A | 4 | Authoritative Bit | 1944 | M | map-request-M | 5 | Map Data Present Bit | 1945 | P | map-request-P | 6 | RLOC-Probe Request Bit | 1946 | S | map-request-S | 7 | Solicit Map-Request (SMR) | 1947 | | | | Bit | 1948 | p | map-request-p | 8 | Proxy-ITR Bit | 1949 | s | map-request-s | 9 | Solicit Map-Request | 1950 | | | | Invoked Bit | 1951 | L | map-request-L | 17 | Local xTR Bit | 1952 | D | map-request-D | 18 | Don't Map-Reply Bit | 1953 +----------+---------------+------------+---------------------------+ 1955 LISP Map-Request Header Bits 1957 Sub-Registry: Map-Reply Header Bits [Section 5.4]: 1959 0 1 2 3 1960 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 1961 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1962 |Type=2 |P|E|S| Reserved | Record Count | 1963 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1965 +-----------+-------------+--------------+------------------------+ 1966 | Spec Name | IANA Name | Bit Position | Description | 1967 +-----------+-------------+--------------+------------------------+ 1968 | P | map-reply-P | 4 | RLOC-Probe Bit | 1969 | E | map-reply-E | 5 | Echo Nonce Capable Bit | 1970 | S | map-reply-S | 6 | Security Bit | 1971 +-----------+-------------+--------------+------------------------+ 1973 LISP Map-Reply Header Bits 1975 Sub-Registry: Map-Register Header Bits [Section 5.6]: 1977 0 1 2 3 1978 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 1979 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1980 |Type=3 |P|S|I| Reserved |E|T|a|R|M| Record Count | 1981 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1982 +-----------+----------------+--------------+----------------------+ 1983 | Spec Name | IANA Name | Bit Position | Description | 1984 +-----------+----------------+--------------+----------------------+ 1985 | P | map-register-P | 4 | Proxy Map-Reply Bit | 1986 | S | map-register-S | 5 | LISP-SEC Capable Bit | 1987 | I | map-register-I | 6 | xTR-ID present flag | 1988 +-----------+----------------+--------------+----------------------+ 1990 LISP Map-Register Header Bits 1992 Sub-Registry: Encapsulated Control Message (ECM) Header Bits 1993 [Section 5.8]: 1995 0 1 2 3 1996 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 1997 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1998 |Type=8 |S|D|E|M| Reserved | 1999 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2001 +-----------+-----------+--------------+----------------------------+ 2002 | Spec Name | IANA Name | Bit Position | Description | 2003 +-----------+-----------+--------------+----------------------------+ 2004 | S | ecm-S | 4 | Security Bit | 2005 | D | ecm-D | 5 | LISP-DDT Bit | 2006 | E | ecm-E | 6 | Forward to ETR Bit | 2007 | M | ecm-M | 7 | Destined to Map-Server Bit | 2008 +-----------+-----------+--------------+----------------------------+ 2010 LISP Encapsulated Control Message (ECM) Header Bits 2012 Sub-Registry: EID-Record Header Bits [Section 5.4]: 2014 0 1 2 3 2015 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 2016 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2017 | Locator Count | EID mask-len | ACT |A| Reserved | 2018 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2020 +-----------+--------------+--------------+-------------------+ 2021 | Spec Name | IANA Name | Bit Position | Description | 2022 +-----------+--------------+--------------+-------------------+ 2023 | A | eid-record-A | 19 | Authoritative Bit | 2024 +-----------+--------------+--------------+-------------------+ 2026 LISP EID-Record Header Bits 2028 Sub-Registry: RLOC-Record Header Bits [Section 5.4]: 2030 0 1 2 3 2031 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 2032 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2033 | Unused Flags |L|p|R| Loc-AFI | 2034 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2036 +-----------+---------------+--------------+----------------------+ 2037 | Spec Name | IANA Name | Bit Position | Description | 2038 +-----------+---------------+--------------+----------------------+ 2039 | L | rloc-record-L | 13 | Local RLOC Bit | 2040 | p | rloc-record-p | 19 | RLOC-Probe Reply Bit | 2041 | R | rloc-record-R | 19 | RLOC Reachable Bit | 2042 +-----------+---------------+--------------+----------------------+ 2044 LISP RLOC-Record Header Bits 2046 13. References 2048 13.1. Normative References 2050 [I-D.ietf-lisp-6834bis] 2051 Iannone, L., Saucez, D., and O. Bonaventure, "Locator/ID 2052 Separation Protocol (LISP) Map-Versioning", draft-ietf- 2053 lisp-6834bis-09 (work in progress), August 2021. 2055 [I-D.ietf-lisp-rfc6830bis] 2056 Farinacci, D., Fuller, V., Meyer, D., Lewis, D., and A. 2057 Cabellos, "The Locator/ID Separation Protocol (LISP)", 2058 draft-ietf-lisp-rfc6830bis-36 (work in progress), November 2059 2020. 2061 [I-D.ietf-lisp-rfc8113bis] 2062 Boucadair, M. and C. Jacquenet, "Locator/ID Separation 2063 Protocol (LISP): Shared Extension Message & IANA Registry 2064 for Packet Type Allocations", draft-ietf-lisp- 2065 rfc8113bis-03 (work in progress), January 2019. 2067 [I-D.ietf-lisp-sec] 2068 Maino, F., Ermagan, V., Cabellos, A., and D. Saucez, 2069 "LISP-Security (LISP-SEC)", draft-ietf-lisp-sec-25 (work 2070 in progress), December 2021. 2072 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 2073 Requirement Levels", BCP 14, RFC 2119, 2074 DOI 10.17487/RFC2119, March 1997, 2075 . 2077 [RFC2404] Madson, C. and R. Glenn, "The Use of HMAC-SHA-1-96 within 2078 ESP and AH", RFC 2404, DOI 10.17487/RFC2404, November 2079 1998, . 2081 [RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, 2082 "Randomness Requirements for Security", BCP 106, RFC 4086, 2083 DOI 10.17487/RFC4086, June 2005, 2084 . 2086 [RFC4868] Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-SHA- 2087 384, and HMAC-SHA-512 with IPsec", RFC 4868, 2088 DOI 10.17487/RFC4868, May 2007, 2089 . 2091 [RFC5869] Krawczyk, H. and P. Eronen, "HMAC-based Extract-and-Expand 2092 Key Derivation Function (HKDF)", RFC 5869, 2093 DOI 10.17487/RFC5869, May 2010, 2094 . 2096 [RFC8085] Eggert, L., Fairhurst, G., and G. Shepherd, "UDP Usage 2097 Guidelines", BCP 145, RFC 8085, DOI 10.17487/RFC8085, 2098 March 2017, . 2100 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for 2101 Writing an IANA Considerations Section in RFCs", BCP 26, 2102 RFC 8126, DOI 10.17487/RFC8126, June 2017, 2103 . 2105 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2106 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2107 May 2017, . 2109 13.2. Informative References 2111 [AFI] "Address Family Identifier (AFIs)", ADDRESS FAMILY 2112 NUMBERS http://www.iana.org/assignments/address-family- 2113 numbers/address-family-numbers.xhtml?, Febuary 2007. 2115 [GTP-3GPP] 2116 "General Packet Radio System (GPRS) Tunnelling Protocol 2117 User Plane (GTPv1-U)", TS.29.281 2118 https://portal.3gpp.org/desktopmodules/Specifications/ 2119 SpecificationDetails.aspx?specificationId=1699, January 2120 2015. 2122 [I-D.herbert-intarea-ila] 2123 Herbert, T. and P. Lapukhov, "Identifier-locator 2124 addressing for IPv6", draft-herbert-intarea-ila-01 (work 2125 in progress), March 2018. 2127 [I-D.ietf-lisp-ecdsa-auth] 2128 Farinacci, D. and E. Nordmark, "LISP Control-Plane ECDSA 2129 Authentication and Authorization", draft-ietf-lisp-ecdsa- 2130 auth-07 (work in progress), February 2022. 2132 [I-D.ietf-lisp-eid-anonymity] 2133 Farinacci, D., Pillay-Esnault, P., and W. Haddad, "LISP 2134 EID Anonymity", draft-ietf-lisp-eid-anonymity-12 (work in 2135 progress), March 2022. 2137 [I-D.ietf-lisp-eid-mobility] 2138 Comeras, M. P., Ashtaputre, V., Maino, F., Moreno, V., and 2139 D. Farinacci, "LISP L2/L3 EID Mobility Using a Unified 2140 Control Plane", draft-ietf-lisp-eid-mobility-09 (work in 2141 progress), January 2022. 2143 [I-D.ietf-lisp-gpe] 2144 Maino, F., Lemon, J., Agarwal, P., Lewis, D., and M. 2145 Smith, "LISP Generic Protocol Extension", draft-ietf-lisp- 2146 gpe-19 (work in progress), July 2020. 2148 [I-D.ietf-lisp-introduction] 2149 Cabellos, A. and D. S. (Ed.), "An Architectural 2150 Introduction to the Locator/ID Separation Protocol 2151 (LISP)", draft-ietf-lisp-introduction-15 (work in 2152 progress), September 2021. 2154 [I-D.ietf-lisp-mn] 2155 Farinacci, D., Lewis, D., Meyer, D., and C. White, "LISP 2156 Mobile Node", draft-ietf-lisp-mn-11 (work in progress), 2157 January 2022. 2159 [I-D.ietf-lisp-pubsub] 2160 Rodriguez-Natal, A., Ermagan, V., Cabellos, A., Barkai, 2161 S., and M. Boucadair, "Publish/Subscribe Functionality for 2162 LISP", draft-ietf-lisp-pubsub-09 (work in progress), June 2163 2021. 2165 [I-D.ietf-nvo3-vxlan-gpe] 2166 (Editor), F. M., (editor), L. K., and U. E. (editor), 2167 "Generic Protocol Extension for VXLAN (VXLAN-GPE)", draft- 2168 ietf-nvo3-vxlan-gpe-12 (work in progress), September 2021. 2170 [I-D.ietf-opsec-icmp-filtering] 2171 Gont, F., Gont, G., and C. Pignataro, "Recommendations for 2172 filtering ICMP messages", draft-ietf-opsec-icmp- 2173 filtering-04 (work in progress), July 2013. 2175 [RFC1035] Mockapetris, P., "Domain names - implementation and 2176 specification", STD 13, RFC 1035, DOI 10.17487/RFC1035, 2177 November 1987, . 2179 [RFC1071] Braden, R., Borman, D., and C. Partridge, "Computing the 2180 Internet checksum", RFC 1071, DOI 10.17487/RFC1071, 2181 September 1988, . 2183 [RFC2104] Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed- 2184 Hashing for Message Authentication", RFC 2104, 2185 DOI 10.17487/RFC2104, February 1997, 2186 . 2188 [RFC2890] Dommety, G., "Key and Sequence Number Extensions to GRE", 2189 RFC 2890, DOI 10.17487/RFC2890, September 2000, 2190 . 2192 [RFC4984] Meyer, D., Ed., Zhang, L., Ed., and K. Fall, Ed., "Report 2193 from the IAB Workshop on Routing and Addressing", 2194 RFC 4984, DOI 10.17487/RFC4984, September 2007, 2195 . 2197 [RFC6234] Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms 2198 (SHA and SHA-based HMAC and HKDF)", RFC 6234, 2199 DOI 10.17487/RFC6234, May 2011, 2200 . 2202 [RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer 2203 Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347, 2204 January 2012, . 2206 [RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The 2207 Locator/ID Separation Protocol (LISP)", RFC 6830, 2208 DOI 10.17487/RFC6830, January 2013, 2209 . 2211 [RFC6831] Farinacci, D., Meyer, D., Zwiebel, J., and S. Venaas, "The 2212 Locator/ID Separation Protocol (LISP) for Multicast 2213 Environments", RFC 6831, DOI 10.17487/RFC6831, January 2214 2013, . 2216 [RFC6832] Lewis, D., Meyer, D., Farinacci, D., and V. Fuller, 2217 "Interworking between Locator/ID Separation Protocol 2218 (LISP) and Non-LISP Sites", RFC 6832, 2219 DOI 10.17487/RFC6832, January 2013, 2220 . 2222 [RFC6836] Fuller, V., Farinacci, D., Meyer, D., and D. Lewis, 2223 "Locator/ID Separation Protocol Alternative Logical 2224 Topology (LISP+ALT)", RFC 6836, DOI 10.17487/RFC6836, 2225 January 2013, . 2227 [RFC6837] Lear, E., "NERD: A Not-so-novel Endpoint ID (EID) to 2228 Routing Locator (RLOC) Database", RFC 6837, 2229 DOI 10.17487/RFC6837, January 2013, 2230 . 2232 [RFC6973] Cooper, A., Tschofenig, H., Aboba, B., Peterson, J., 2233 Morris, J., Hansen, M., and R. Smith, "Privacy 2234 Considerations for Internet Protocols", RFC 6973, 2235 DOI 10.17487/RFC6973, July 2013, 2236 . 2238 [RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger, 2239 L., Sridhar, T., Bursell, M., and C. Wright, "Virtual 2240 eXtensible Local Area Network (VXLAN): A Framework for 2241 Overlaying Virtualized Layer 2 Networks over Layer 3 2242 Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014, 2243 . 2245 [RFC7835] Saucez, D., Iannone, L., and O. Bonaventure, "Locator/ID 2246 Separation Protocol (LISP) Threat Analysis", RFC 7835, 2247 DOI 10.17487/RFC7835, April 2016, 2248 . 2250 [RFC8060] Farinacci, D., Meyer, D., and J. Snijders, "LISP Canonical 2251 Address Format (LCAF)", RFC 8060, DOI 10.17487/RFC8060, 2252 February 2017, . 2254 [RFC8061] Farinacci, D. and B. Weis, "Locator/ID Separation Protocol 2255 (LISP) Data-Plane Confidentiality", RFC 8061, 2256 DOI 10.17487/RFC8061, February 2017, 2257 . 2259 [RFC8111] Fuller, V., Lewis, D., Ermagan, V., Jain, A., and A. 2260 Smirnov, "Locator/ID Separation Protocol Delegated 2261 Database Tree (LISP-DDT)", RFC 8111, DOI 10.17487/RFC8111, 2262 May 2017, . 2264 [RFC8378] Moreno, V. and D. Farinacci, "Signal-Free Locator/ID 2265 Separation Protocol (LISP) Multicast", RFC 8378, 2266 DOI 10.17487/RFC8378, May 2018, 2267 . 2269 [RFC8402] Filsfils, C., Ed., Previdi, S., Ed., Ginsberg, L., 2270 Decraene, B., Litkowski, S., and R. Shakir, "Segment 2271 Routing Architecture", RFC 8402, DOI 10.17487/RFC8402, 2272 July 2018, . 2274 Appendix A. Acknowledgments 2276 The original authors would like to thank Greg Schudel, Darrel Lewis, 2277 John Zwiebel, Andrew Partan, Dave Meyer, Isidor Kouvelas, Jesper 2278 Skriver, Fabio Maino, and members of the lisp@ietf.org mailing list 2279 for their feedback and helpful suggestions. 2281 Special thanks are due to Noel Chiappa for his extensive work and 2282 thought about caching in Map-Resolvers. 2284 The current authors would like to give a sincere thank you to the 2285 people who help put LISP on standards track in the IETF. They 2286 include Joel Halpern, Luigi Iannone, Deborah Brungard, Fabio Maino, 2287 Scott Bradner, Kyle Rose, Takeshi Takahashi, Sarah Banks, Pete 2288 Resnick, Colin Perkins, Mirja Kuhlewind, Francis Dupont, Benjamin 2289 Kaduk, Eric Rescorla, Alvaro Retana, Alexey Melnikov, Alissa Cooper, 2290 Suresh Krishnan, Alberto Rodriguez-Natal, Vina Ermagen, Mohamed 2291 Boucadair, Brian Trammell, Sabrina Tanamal, and John Drake. The 2292 contributions they offered greatly added to the security, scale, and 2293 robustness of the LISP architecture and protocols. 2295 Appendix B. Document Change Log 2297 [RFC Editor: Please delete this section on publication as RFC.] 2299 B.1. Changes to draft-ietf-lisp-rfc6833bis-31 2301 o Posted May 2020. 2303 o Added reference to 6834bis when describing the syntax and action 2304 of the Map-Version field in the Map-Reply section. This is so we 2305 can advance the Map-Versioning draft rfc6834bis to proposed 2306 standard. 2308 B.2. Changes to draft-ietf-lisp-rfc6833bis-26 2310 o Posted November 2019. 2312 o Fixed the required (MUST implement) authentcation algorithms. 2314 o Fixed a large set of minor comments and edits. 2316 B.3. Changes to draft-ietf-lisp-rfc6833bis-25 2318 o Posted June 2019. 2320 o Added change requested by Mirja describing Record Count in an EID- 2321 record. 2323 o Fixed Requirements Notation section per Pete. 2325 o Added KDF for shared-secret 2327 o Specified several rate-limiters for control messages 2329 B.4. Changes to draft-ietf-lisp-rfc6833bis-24 2331 o Posted February 2019. 2333 o Added suggested text from Albert that Benjamin Kaduk agreed with. 2335 o Added suggested editorial comments from Alvaro's rewview. 2337 o Ran document through IDnits. Fixed bugs found. 2339 B.5. Changes to draft-ietf-lisp-rfc6833bis-23 2341 o Posted December 2018. 2343 o Added to Security Considerations section that deployments that 2344 care about prefix over claiming should use LISP-SEC. 2346 o Added to Security Considerations section that DTLS or LISP-crypto 2347 be used for control-plane privacy. 2349 o Make LISP-SEC a normative reference. 2351 o Make it more clear where field descriptions are spec'ed when 2352 referencing to the same fields in other packet types. 2354 B.6. Changes to draft-ietf-lisp-rfc6833bis-22 2356 o Posted week after IETF November 2018. 2358 o No longer need to use IPSEC for replay attacks. 2360 B.7. Changes to draft-ietf-lisp-rfc6833bis-21 2362 o Posted early November 2018. 2364 o Added I-bit back in because its necessary to use for Map-Register 2365 replay attack scenarios. The Map-Server tracks the nonce per xTR- 2366 ID to detect duplicate or replayed Map-Register messages. 2368 B.8. Changes to draft-ietf-lisp-rfc6833bis-20 2370 o Posted late October 2018. 2372 o Changed description about "reserved" bits to state "reserved and 2373 unassigned". 2375 o Make it more clear how Map-Register nonce processing is performed 2376 in an ETR and Map-Server. 2378 B.9. Changes to draft-ietf-lisp-rfc6833bis-19 2380 o Posted mid October 2018. 2382 o Added Fabio text to the Security Considerations section. 2384 B.10. Changes to draft-ietf-lisp-rfc6833bis-18 2386 o Posted mid October 2018. 2388 o Fixed comments from Eric after more email clarity. 2390 B.11. Changes to draft-ietf-lisp-rfc6833bis-17 2392 o Posted early October 2018. 2394 o Changes to reflect comments from Sep 27th Telechat. 2396 o Added all flag bit definitions as request for allocation in IANA 2397 Considersations section. 2399 o Added an applicability statement in section 1 to address security 2400 concerns from Telechat. 2402 o Moved m-bit description and IANA request to draft-ietf-lisp-mn. 2404 o Moved I-bit description and IANA request to draft-ietf-lisp- 2405 pubsub. 2407 B.12. Changes to draft-ietf-lisp-rfc6833bis-16 2409 o Posted Late-September 2018. 2411 o Re-wrote Security Considerations section. Thanks Albert. 2413 o Added Alvaro text to be more clear about IANA actions. 2415 B.13. Changes to draft-ietf-lisp-rfc6833bis-15 2417 o Posted mid-September 2018. 2419 o Changes to reflect comments from Colin and Mirja. 2421 B.14. Changes to draft-ietf-lisp-rfc6833bis-14 2423 o Posted September 2018. 2425 o Changes to reflect comments from Genart, RTGarea, and Secdir 2426 reviews. 2428 B.15. Changes to draft-ietf-lisp-rfc6833bis-13 2430 o Posted August 2018. 2432 o Final editorial changes before RFC submission for Proposed 2433 Standard. 2435 o Added section "Changes since RFC 6833" so implementators are 2436 informed of any changes since the last RFC publication. 2438 B.16. Changes to draft-ietf-lisp-rfc6833bis-12 2440 o Posted late July 2018. 2442 o Moved RFC6830bis and RFC6834bis to Normative References. 2444 B.17. Changes to draft-ietf-lisp-rfc6833bis-11 2446 o Posted July 2018. 2448 o Fixed Luigi editorial comments to ready draft for RFC status and 2449 ran through IDNITs again. 2451 B.18. Changes to draft-ietf-lisp-rfc6833bis-10 2453 o Posted after LISP WG at IETF week March. 2455 o Move AD field encoding after S-bit in the ECM packet format 2456 description section. 2458 o Say more about when the new Drop actions should be sent. 2460 B.19. Changes to draft-ietf-lisp-rfc6833bis-09 2462 o Posted March IETF week 2018. 2464 o Fixed editorial comments submitted by document shepherd Luigi 2465 Iannone. 2467 B.20. Changes to draft-ietf-lisp-rfc6833bis-08 2469 o Posted March 2018. 2471 o Added RLOC-probing algorithm. 2473 o Added Solicit-Map Request algorithm. 2475 o Added several mechanisms (from 6830bis) regarding Routing Locator 2476 Reachability. 2478 o Added port 4342 to IANA Considerations section. 2480 B.21. Changes to draft-ietf-lisp-rfc6833bis-07 2482 o Posted December 2017. 2484 o Make it more clear in a couple of places that RLOCs are used to 2485 locate ETRs more so than for Map-Server Map-Request forwarding. 2487 o Make it clear that "encapsualted" for a control message is an ECM 2488 based message. 2490 o Make it more clear what messages use source-port 4342 and which 2491 ones use destinatino-port 4342. 2493 o Don't make DDT references when the mapping transport system can be 2494 of any type and the referneced text is general to it. 2496 o Generalize text when referring to the format of an EID-prefix. 2497 Can use othe AFIs then IPv4 and IPv6. 2499 o Many editorial changes to clarify text. 2501 o Changed some "must", "should", and "may" to capitalized. 2503 o Added definitions for Map-Request and Map-Reply messages. 2505 o Ran document through IDNITs. 2507 B.22. Changes to draft-ietf-lisp-rfc6833bis-06 2509 o Posted October 2017. 2511 o Spec the I-bit to include the xTR-ID in a Map-Request message to 2512 be consistent with the Map-Register message and to anticipate the 2513 introduction of pubsub functionality to allow Map-Requests to 2514 subscribe to RLOC-set changes. 2516 o Updated references for individual submissions that became working 2517 group documents. 2519 o Updated references for working group documents that became RFCs. 2521 B.23. Changes to draft-ietf-lisp-rfc6833bis-05 2523 o Posted May 2017. 2525 o Update IANA Considerations section based on new requests from this 2526 document and changes from what was requested in [RFC6830]. 2528 B.24. Changes to draft-ietf-lisp-rfc6833bis-04 2530 o Posted May 2017. 2532 o Clarify how the Key-ID field is used in Map-Register and Map- 2533 Notify messages. Break the 16-bit field into a 8-bit Key-ID field 2534 and a 8-bit Algorithm-ID field. 2536 o Move the Control-Plane codepoints from the IANA Considerations 2537 section of RFC6830bis to the IANA Considerations section of this 2538 document. 2540 o In the "LISP Control Packet Type Allocations" section, indicate 2541 how message Types are IANA allocated and how experimental RFC8113 2542 sub-types should be requested. 2544 B.25. Changes to draft-ietf-lisp-rfc6833bis-03 2546 o Posted April 2017. 2548 o Add types 9-14 and specify they are not assigned. 2550 o Add the "LISP Shared Extension Message" type and point to RFC8113. 2552 B.26. Changes to draft-ietf-lisp-rfc6833bis-02 2554 o Posted April 2017. 2556 o Clarify that the LISP Control-Plane document defines how the LISP 2557 Data-Plane uses Map-Requests with either the SMR-bit set or the 2558 P-bit set supporting mapping updates and RLOC-probing. Indicating 2559 that other Data-Planes can use the same mechanisms or their own 2560 defined mechanisms to achieve the same functionality. 2562 B.27. Changes to draft-ietf-lisp-rfc6833bis-01 2564 o Posted March 2017. 2566 o Include references to new RFCs published. 2568 o Remove references to self. 2570 o Change references from RFC6830 to RFC6830bis. 2572 o Add two new action/reasons to a Map-Reply has posted to the LISP 2573 WG mailing list. 2575 o In intro section, add refernece to I-D.ietf-lisp-introduction. 2577 o Removed Open Issues section and references to "experimental". 2579 B.28. Changes to draft-ietf-lisp-rfc6833bis-00 2581 o Posted December 2016. 2583 o Created working group document from draft-farinacci-lisp 2584 -rfc6833-00 individual submission. No other changes made. 2586 B.29. Changes to draft-farinacci-lisp-rfc6833bis-00 2588 o Posted November 2016. 2590 o This is the initial draft to turn RFC 6833 into RFC 6833bis. 2592 o The document name has changed from the "Locator/ID Separation 2593 Protocol (LISP) Map-Server Interface" to the "Locator/ID 2594 Separation Protocol (LISP) Control-Plane". 2596 o The fundamental change was to move the Control-Plane messages from 2597 RFC 6830 to this document in an effort so any IETF developed or 2598 industry created Data-Plane could use the LISP mapping system and 2599 Control-Plane. 2601 o Update Control-Plane messages to incorporate what has been 2602 implemented in products during the early phase of LISP development 2603 but wasn't able to make it into RFC6830 and RFC6833 to make the 2604 Experimental RFC deadline. 2606 o Indicate there may be nodes in the mapping system that are not MRs 2607 or MSs, that is a ALT-node or a DDT-node. 2609 o Include LISP-DDT in Map-Resolver section and explain how they 2610 maintain a referral-cache. 2612 o Removed open issue about additional state in Map-Servers. With 2613 [RFC8111], Map-Servers have the same registration state and can 2614 give Map-Resolvers complete information in ms-ack Map-Referral 2615 messages. 2617 o Make reference to the LISP Threats Analysis RFC [RFC7835]. 2619 Authors' Addresses 2621 Dino Farinacci 2622 lispers.net 2624 EMail: farinacci@gmail.com 2626 Fabio Maino 2627 Cisco Systems 2629 EMail: fmaino@cisco.com 2631 Vince Fuller 2632 vaf.net Internet Consulting 2634 EMail: vaf@vaf.net 2636 Albert Cabellos 2637 UPC/BarcelonaTech 2638 Campus Nord, C. Jordi Girona 1-3 2639 Barcelona, Catalunya 2640 Spain 2642 EMail: acabello@ac.upc.edu