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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: January 30, 2021 V. Fuller 7 vaf.net Internet Consulting 8 A. Cabellos (Ed.) 9 UPC/BarcelonaTech 10 July 29, 2020 12 Locator/ID Separation Protocol (LISP) Control-Plane 13 draft-ietf-lisp-rfc6833bis-28 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, their implementation and operational complexity 30 reduces 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 January 30, 2021. 50 Copyright Notice 52 Copyright (c) 2020 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 . . . . . . . . . . . . . . . . 17 77 5.5. EID-to-RLOC UDP Map-Reply Message . . . . . . . . . . . . 21 78 5.6. Map-Register Message Format . . . . . . . . . . . . . . . 24 79 5.7. Map-Notify/Map-Notify-Ack Message Format . . . . . . . . 28 80 5.8. Encapsulated Control Message Format . . . . . . . . . . . 30 81 6. Changing the Contents of EID-to-RLOC Mappings . . . . . . . . 32 82 6.1. Solicit-Map-Request (SMR) . . . . . . . . . . . . . . . . 32 83 7. Routing Locator Reachability . . . . . . . . . . . . . . . . 33 84 7.1. RLOC-Probing Algorithm . . . . . . . . . . . . . . . . . 34 85 8. Interactions with Other LISP Components . . . . . . . . . . . 35 86 8.1. ITR EID-to-RLOC Mapping Resolution . . . . . . . . . . . 35 87 8.2. EID-Prefix Configuration and ETR Registration . . . . . . 36 88 8.3. Map-Server Processing . . . . . . . . . . . . . . . . . . 38 89 8.4. Map-Resolver Processing . . . . . . . . . . . . . . . . . 39 90 8.4.1. Anycast Operation . . . . . . . . . . . . . . . . . . 39 91 9. Security Considerations . . . . . . . . . . . . . . . . . . . 40 92 10. Privacy Considerations . . . . . . . . . . . . . . . . . . . 41 93 11. Changes since RFC 6833 . . . . . . . . . . . . . . . . . . . 42 94 12. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 42 95 12.1. LISP UDP Port Numbers . . . . . . . . . . . . . . . . . 43 96 12.2. LISP Packet Type Codes . . . . . . . . . . . . . . . . . 43 97 12.3. LISP Map-Reply EID-Record Action Codes . . . . . . . . . 43 98 12.4. LISP Address Type Codes . . . . . . . . . . . . . . . . 44 99 12.5. LISP Algorithm ID Numbers . . . . . . . . . . . . . . . 44 100 12.6. LISP Bit Flags . . . . . . . . . . . . . . . . . . . . . 45 101 13. References . . . . . . . . . . . . . . . . . . . . . . . . . 48 102 13.1. Normative References . . . . . . . . . . . . . . . . . . 48 103 13.2. Informative References . . . . . . . . . . . . . . . . . 49 104 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 53 105 Appendix B. Document Change Log . . . . . . . . . . . . . . . . 53 106 B.1. Changes to draft-ietf-lisp-rfc6833bis-26 . . . . . . . . 53 107 B.2. Changes to draft-ietf-lisp-rfc6833bis-25 . . . . . . . . 53 108 B.3. Changes to draft-ietf-lisp-rfc6833bis-24 . . . . . . . . 54 109 B.4. Changes to draft-ietf-lisp-rfc6833bis-23 . . . . . . . . 54 110 B.5. Changes to draft-ietf-lisp-rfc6833bis-22 . . . . . . . . 54 111 B.6. Changes to draft-ietf-lisp-rfc6833bis-21 . . . . . . . . 54 112 B.7. Changes to draft-ietf-lisp-rfc6833bis-20 . . . . . . . . 54 113 B.8. Changes to draft-ietf-lisp-rfc6833bis-19 . . . . . . . . 55 114 B.9. Changes to draft-ietf-lisp-rfc6833bis-18 . . . . . . . . 55 115 B.10. Changes to draft-ietf-lisp-rfc6833bis-17 . . . . . . . . 55 116 B.11. Changes to draft-ietf-lisp-rfc6833bis-16 . . . . . . . . 55 117 B.12. Changes to draft-ietf-lisp-rfc6833bis-15 . . . . . . . . 55 118 B.13. Changes to draft-ietf-lisp-rfc6833bis-14 . . . . . . . . 55 119 B.14. Changes to draft-ietf-lisp-rfc6833bis-13 . . . . . . . . 56 120 B.15. Changes to draft-ietf-lisp-rfc6833bis-12 . . . . . . . . 56 121 B.16. Changes to draft-ietf-lisp-rfc6833bis-11 . . . . . . . . 56 122 B.17. Changes to draft-ietf-lisp-rfc6833bis-10 . . . . . . . . 56 123 B.18. Changes to draft-ietf-lisp-rfc6833bis-09 . . . . . . . . 56 124 B.19. Changes to draft-ietf-lisp-rfc6833bis-08 . . . . . . . . 56 125 B.20. Changes to draft-ietf-lisp-rfc6833bis-07 . . . . . . . . 57 126 B.21. Changes to draft-ietf-lisp-rfc6833bis-06 . . . . . . . . 57 127 B.22. Changes to draft-ietf-lisp-rfc6833bis-05 . . . . . . . . 58 128 B.23. Changes to draft-ietf-lisp-rfc6833bis-04 . . . . . . . . 58 129 B.24. Changes to draft-ietf-lisp-rfc6833bis-03 . . . . . . . . 58 130 B.25. Changes to draft-ietf-lisp-rfc6833bis-02 . . . . . . . . 58 131 B.26. Changes to draft-ietf-lisp-rfc6833bis-01 . . . . . . . . 58 132 B.27. Changes to draft-ietf-lisp-rfc6833bis-00 . . . . . . . . 59 133 B.28. Changes to draft-farinacci-lisp-rfc6833bis-00 . . . . . . 59 134 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 60 136 1. Introduction 138 The Locator/ID Separation Protocol [I-D.ietf-lisp-rfc6830bis] (see 139 also [I-D.ietf-lisp-introduction]) specifies an architecture and 140 mechanism for dynamic tunneling by logically separating the addresses 141 currently used by IP in two separate name spaces: Endpoint IDs 142 (EIDs), used within sites; and Routing Locators (RLOCs), used on the 143 transit networks that make up the Internet infrastructure. To 144 achieve this separation, LISP defines protocol mechanisms for mapping 145 from EIDs to RLOCs. In addition, LISP assumes the existence of a 146 database to store and propagate those mappings across mapping system 147 nodes. Several such databases have been proposed; among them are the 148 Content distribution Overlay Network Service for LISP-NERD (a Not-so- 149 novel EID-to-RLOC Database) [RFC6837], LISP Alternative Logical 150 Topology (LISP-ALT) [RFC6836], and LISP Delegated Database Tree 151 (LISP-DDT) [RFC8111]. 153 The LISP Mapping Service defines two types of LISP-speaking devices: 154 the Map-Resolver, which accepts Map-Requests from an Ingress Tunnel 155 Router (ITR) and "resolves" the EID-to-RLOC mapping using a mapping 156 database; and the Map-Server, which learns authoritative EID-to-RLOC 157 mappings from an Egress Tunnel Router (ETR) and publishes them in a 158 database. 160 This LISP Control-Plane Mapping Service can be used by many different 161 encapsulation-based or translation-based Data-Planes which include 162 but are not limited to the ones defined in LISP RFC 6830bis 163 [I-D.ietf-lisp-rfc6830bis], LISP-GPE [I-D.ietf-lisp-gpe], VXLAN 164 [RFC7348], VXLAN-GPE [I-D.ietf-nvo3-vxlan-gpe], GRE [RFC2890], GTP 165 [GTP-3GPP], ILA [I-D.herbert-intarea-ila], and Segment Routing (SRv6) 166 [RFC8402]. 168 Conceptually, LISP Map-Servers share some of the same basic 169 configuration and maintenance properties as Domain Name System (DNS) 170 [RFC1035] servers; likewise, Map-Resolvers are conceptually similar 171 to DNS caching resolvers. With this in mind, this specification 172 borrows familiar terminology (resolver and server) from the DNS 173 specifications. 175 Note this document doesn't assume any particular database mapping 176 infrastructure to illustrate certain aspects of Map-Server and Map- 177 Resolver operation. The Mapping Service interface can (and likely 178 will) be used by ITRs and ETRs to access other mapping database 179 systems as the LISP infrastructure evolves. 181 LISP is not intended to address problems of connectivity and scaling 182 on behalf of arbitrary communicating parties. Relevant situations 183 are described in the scoping section of the introduction to 184 [I-D.ietf-lisp-rfc6830bis]. 186 This document obsoletes RFC 6830 and 6833. 188 1.1. Scope of Applicability 190 LISP was originally developed to address the Internet-wide route 191 scaling problem [RFC4984]. While there are a number of approaches of 192 interest for that problem, as LISP as been developed and refined, a 193 large number of other LISP uses have been found and are being used. 194 As such, the design and development of LISP has changed so as to 195 focus on these use cases. The common property of these uses is a 196 large set of cooperating entities seeking to communicate over the 197 public Internet or other large underlay IP infrastructures, while 198 keeping the addressing and topology of the cooperating entities 199 separate from the underlay and Internet topology, routing, and 200 addressing. 202 When communicating over the public Internet, deployers MUST consider 203 the following guidelines: 205 1. LISP-SEC MUST be implemented [I-D.ietf-lisp-sec]. This means 206 that the S-bit MUST be set in the Map-Reply (Section 5.4), Map- 207 Register (Section 5.6) and Encapsulated Control messages 208 (Section 5.8). 210 2. Implementations SHOULD use the 'HMAC-SHA256-128+HKDF-SHA256' as 211 the Algorithm ID (Section 12.5) in Map-Register message 212 (Section 5.6), and MUST NOT use 'None' or 'HMAC-SHA-1-96-None' as 213 Algorithm ID (Section 12.5) in the Map-Register message 214 (Section 5.6) 216 2. Requirements Notation 218 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 219 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 220 "OPTIONAL" in this document are to be interpreted as described in BCP 221 14 [RFC2119] [RFC8174] when, and only when, they appear in all 222 capitals, as shown here. 224 3. Definition of Terms 226 Map-Server: A network infrastructure component that learns of EID- 227 Prefix mapping entries from an ETR, via the registration mechanism 228 described below, or some other authoritative source if one exists. 229 A Map-Server publishes these EID-Prefixes in a mapping database. 231 Map-Request: A LISP Map-Request is a Control-Plane message to query 232 the mapping system to resolve an EID. A LISP Map-Request can also 233 be sent to an RLOC to test for reachability and to exchange 234 security keys between an encapsulator and a decapsulator. This 235 type of Map-Request is also known as an RLOC-Probe Request. 237 Map-Reply: A LISP Map-Reply is a Control-Plane message returned in 238 response to a Map-Request sent to the mapping system when 239 resolving an EID. A LISP Map-Reply can also be returned by a 240 decapsulator in response to a Map-Request sent by an encapsulator 241 to test for reachability. This type of Map-Reply is known as a 242 RLOC-Probe Reply. 244 Encapsulated Map-Request: A LISP Map-Request carried within an 245 Encapsulated Control Message (ECM), which has an additional LISP 246 header prepended. Sent to UDP destination port 4342. The "outer" 247 addresses are routable IP addresses, also known as RLOCs. Used by 248 an ITR when sending to a Map-Resolver and by a Map-Server when 249 forwarding a Map-Request to an ETR. 251 Map-Resolver: A network infrastructure component that accepts LISP 252 Encapsulated (ECM) Map-Requests, typically from an ITR, and 253 determines whether or not the destination IP address is part of 254 the EID namespace; if it is not, a Negative Map-Reply is returned. 255 Otherwise, the Map-Resolver finds the appropriate EID-to-RLOC 256 mapping by consulting a mapping database system. 258 Negative Map-Reply: A LISP Map-Reply that contains an empty 259 Locator-Set. Returned in response to a Map-Request if the 260 destination EID is not registered in the mapping system, is policy 261 denied or fails authentication. 263 Map-Register message: A LISP message sent by an ETR to a Map-Server 264 to register its associated EID-Prefixes. In addition to the set 265 of EID-Prefixes to register, the message includes one or more 266 RLOCs to reach ETR(s). The Map-Server uses these RLOCs when 267 forwarding Map-Requests (re-formatted as Encapsulated Map- 268 Requests). An ETR MAY request that the Map-Server answer Map- 269 Requests on its behalf by setting the "proxy Map-Reply" flag 270 (P-bit) in the message. 272 Map-Notify message: A LISP message sent by a Map-Server to an ETR 273 to confirm that a Map-Register has been received and processed. 274 An ETR requests that a Map-Notify be returned by setting the 275 "want-map-notify" flag (M-bit) in the Map-Register message. 276 Unlike a Map-Reply, a Map-Notify uses UDP port 4342 for both 277 source and destination. Map-Notify messages are also sent to ITRs 278 by Map-Servers when there are RLOC-set changes. 280 For definitions of other terms, notably Ingress Tunnel Router (ITR), 281 Egress Tunnel Router (ETR), and Re-encapsulating Tunnel Router (RTR), 282 refer to the LISP Data-Plane specification 283 [I-D.ietf-lisp-rfc6830bis]. 285 4. Basic Overview 287 A Map-Server is a device that publishes EID-Prefixes in a LISP 288 mapping database on behalf of a set of ETRs. When it receives a Map 289 Request (typically from an ITR), it consults the mapping database to 290 find an ETR that can answer with the set of RLOCs for an EID-Prefix. 291 To publish its EID-Prefixes, an ETR periodically sends Map-Register 292 messages to the Map-Server. A Map-Register message contains a list 293 of EID-Prefixes plus a set of RLOCs that can be used to reach the 294 ETRs. 296 When LISP-ALT [RFC6836] is used as the mapping database, a Map-Server 297 connects to the ALT network and acts as a "last-hop" ALT-Router. 298 Intermediate ALT-Routers forward Map-Requests to the Map-Server that 299 advertises a particular EID-Prefix, and the Map-Server forwards them 300 to the owning ETR, which responds with Map-Reply messages. 302 When LISP-DDT [RFC8111] is used as the mapping database, a Map-Server 303 sends the final Map-Referral messages from the Delegated Database 304 Tree. 306 A Map-Resolver receives Encapsulated Map-Requests from its client 307 ITRs and uses a mapping database system to find the appropriate ETR 308 to answer those requests. On a LISP-ALT network, a Map-Resolver acts 309 as a "first-hop" ALT-Router. It has Generic Routing Encapsulation 310 (GRE) tunnels configured to other ALT-Routers and uses BGP to learn 311 paths to ETRs for different prefixes in the LISP-ALT database. The 312 Map-Resolver uses this path information to forward Map-Requests over 313 the ALT to the correct ETRs. On a LISP-DDT network [RFC8111], a Map- 314 Resolver maintains a referral-cache and acts as a "first-hop" DDT- 315 node. The Map-Resolver uses the referral information to forward Map- 316 Requests. 318 Note that while it is conceivable that a Map-Resolver could cache 319 responses to improve performance, issues surrounding cache management 320 would need to be resolved so that doing so will be reliable and 321 practical. In this specification, Map-Resolvers will operate only in 322 a non-caching mode, decapsulating and forwarding Encapsulated Map 323 Requests received from ITRs. Any specification of caching 324 functionality is out of scope for this document. 326 Note that a single device can implement the functions of both a Map- 327 Server and a Map-Resolver, and in many cases the functions will be 328 co-located in that way. Also, there can be ALT-only nodes and DDT- 329 only nodes, when LISP-ALT and LISP-DDT are used, respectively, to 330 connecting Map-Resolvers and Map-Servers together to make up the 331 Mapping System. 333 5. LISP IPv4 and IPv6 Control-Plane Packet Formats 335 The following UDP packet formats are used by the LISP control plane. 337 0 1 2 3 338 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 1 339 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 340 |Version| IHL |Type of Service| Total Length | 341 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 342 | Identification |Flags| Fragment Offset | 343 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 344 | Time to Live | Protocol = 17 | Header Checksum | 345 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 346 | Source Routing Locator | 347 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 348 | Destination Routing Locator | 349 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 350 / | Source Port | Dest Port | 351 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 352 \ | UDP Length | UDP Checksum | 353 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 354 | | 355 | LISP Message | 356 | | 357 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 359 IPv4 UDP LISP Control Message 361 0 1 2 3 362 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 1 363 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 364 |Version| Traffic Class | Flow Label | 365 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 366 | Payload Length | Next Header=17| Hop Limit | 367 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 368 | | 369 + + 370 | | 371 + Source Routing Locator + 372 | | 373 + + 374 | | 375 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 376 | | 377 + + 378 | | 379 + Destination Routing Locator + 380 | | 381 + + 382 | | 383 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 384 / | Source Port | Dest Port | 385 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 386 \ | UDP Length | UDP Checksum | 387 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 388 | | 389 | LISP Message | 390 | | 391 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 393 IPv6 UDP LISP Control Message 395 When a UDP Map-Request, Map-Register, or Map-Notify (when used as a 396 notification message) are sent, the UDP source port is chosen by the 397 sender and the destination UDP port number is set to 4342. When a 398 UDP Map-Reply, Map-Notify (when used as an acknowledgement to a Map- 399 Register), or Map-Notify-Ack are sent, the source UDP port number is 400 set to 4342 and the destination UDP port number is copied from the 401 source port of either the Map-Request or the invoking data packet. 402 Implementations MUST be prepared to accept packets when either the 403 source port or destination UDP port is set to 4342 due to NATs 404 changing port number values. 406 The 'UDP Length' field will reflect the length of the UDP header and 407 the LISP Message payload. LISP is expected to be deployed by 408 cooperating entities communicating over underlays. Deployers are 409 expected to set the MTU according to the specific deployment 410 guidelines to prevent fragmentation of either the inner packet or the 411 outer encapsulated packet. For deployments not aware of the underlay 412 restrictions on path MTU, the message size MUST be limited to 576 413 bytes for IPv4 or 1280 bytes for IPv6 -considering the entire IP 414 packet- as outlined in [RFC8085]. 416 The UDP checksum is computed and set to non-zero for all messages 417 sent to or from port 4342. It MUST be checked on receipt, and if the 418 checksum fails, the control message MUST be dropped [RFC1071]. 420 The format of control messages includes the UDP header so the 421 checksum and length fields can be used to protect and delimit message 422 boundaries. 424 5.1. LISP Control Packet Type Allocations 426 This section defines the LISP control message formats and summarizes 427 for IANA the LISP Type codes assigned by this document. For 428 completeness, the summary below includes the LISP Shared Extension 429 Message assigned by [I-D.ietf-lisp-rfc8113bis]. Message type 430 definitions are: 432 Reserved: 0 b'0000' 433 LISP Map-Request: 1 b'0001' 434 LISP Map-Reply: 2 b'0010' 435 LISP Map-Register: 3 b'0011' 436 LISP Map-Notify: 4 b'0100' 437 LISP Map-Notify-Ack: 5 b'0101' 438 LISP Map-Referral: 6 b'0110' 439 Unassigned 7 b'0111' 440 LISP Encapsulated Control Message: 8 b'1000' 441 Unassigned 9-14 b'1001'- b'1110' 442 LISP Shared Extension Message: 15 b'1111' 444 Protocol designers experimenting with new message formats are 445 recommended to use the LISP Shared Extension Message Type described 446 in [I-D.ietf-lisp-rfc8113bis]. 448 All LISP Control-Plane messages use Address Family Identifiers (AFI) 449 [AFI] or LISP Canonical Address Format (LCAF) [RFC8060] formats to 450 encode either fixed or variable length addresses. This includes 451 explicit fields in each control message or part of EID-records or 452 RLOC-records in commonly formatted messages. 454 The LISP control-plane describes how other data-planes can encode 455 messages to support the Soliciting of Map-Requests as well as RLOC- 456 probing procedures. 458 5.2. Map-Request Message Format 460 0 1 2 3 461 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 1 462 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 463 |Type=1 |A|M|P|S|p|s|R|R| Rsvd |L|D| IRC | Record Count | 464 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 465 | Nonce . . . | 466 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 467 | . . . Nonce | 468 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 469 | Source-EID-AFI | Source EID Address ... | 470 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 471 | ITR-RLOC-AFI 1 | ITR-RLOC Address 1 ... | 472 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 473 | ... | 474 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 475 | ITR-RLOC-AFI n | ITR-RLOC Address n ... | 476 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 477 / | Reserved | EID mask-len | EID-Prefix-AFI | 478 Rec +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 479 \ | EID-Prefix ... | 480 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 481 | Map-Reply Record ... | 482 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 484 Packet field descriptions: 486 Type: 1 (Map-Request) 488 A: This is an authoritative bit, which is set to 0 for UDP-based Map- 489 Requests sent by an ITR. It is set to 1 when an ITR wants the 490 destination site to return the Map-Reply rather than the mapping 491 database system returning a Map-Reply. 493 M: This is the map-data-present bit. When set, it indicates that a 494 Map-Reply Record segment is included in the Map-Request. 496 P: This is the probe-bit, which indicates that a Map-Request MUST be 497 treated as a Locator reachability probe. The receiver MUST 498 respond with a Map-Reply with the probe-bit set, indicating that 499 the Map-Reply is a Locator reachability probe reply, with the 500 nonce copied from the Map-Request. See RLOC-Probing Section 7.1 501 for more details. This RLOC-probe Map-Request MUST NOT be sent to 502 the mapping system. If a Map-Resolver or Map-Server receives a 503 Map-Request with the probe-bit set, it MUST drop the message. 505 S: This is the Solicit-Map-Request (SMR) bit. See Solicit-Map- 506 Request (SMRs) Section 6.1 for details. 508 p: This is the PITR bit. This bit is set to 1 when a PITR sends a 509 Map-Request. 511 s: This is the SMR-invoked bit. This bit is set to 1 when an xTR is 512 sending a Map-Request in response to a received SMR-based Map- 513 Request. 515 R: This reserved and unassigned bit MUST be set to 0 on transmit and 516 MUST be ignored on receipt. 518 Rsvd: This field MUST be set to 0 on transmit and MUST be ignored on 519 receipt. 521 L: This is the local-xtr bit. It is used by an xTR in a LISP site to 522 tell other xTRs in the same site that it is part of the RLOC-set 523 for the LISP site. The L-bit is set to 1 when the RLOC is the 524 sender's IP address. 526 D: This is the dont-map-reply bit. It is used in the SMR procedure 527 described in Section 6.1. When an xTR sends an SMR Map-Request 528 message, it doesn't need a Map-Reply returned. When this bit is 529 set, the receiver of the Map-Request does not return a Map-Reply. 531 IRC: This 5-bit field is the ITR-RLOC Count, which encodes the 532 additional number of ('ITR-RLOC-AFI', 'ITR-RLOC Address') fields 533 present in this message. At least one (ITR-RLOC-AFI, ITR-RLOC- 534 Address) pair MUST be encoded. Multiple 'ITR-RLOC Address' fields 535 are used, so a Map-Replier can select which destination address to 536 use for a Map-Reply. The IRC value ranges from 0 to 31. For a 537 value of 0, there is 1 ITR-RLOC address encoded; for a value of 1, 538 there are 2 ITR-RLOC addresses encoded, and so on up to 31, which 539 encodes a total of 32 ITR-RLOC addresses. 541 Record Count: This is the number of records in this Map-Request 542 message. A record is comprised of the portion of the packet that 543 is labeled 'Rec' above and occurs the number of times equal to 544 Record Count. For this version of the protocol, a receiver MUST 545 accept and process Map-Requests that contain one or more records, 546 but a sender MUST only send Map-Requests containing one record. 548 Nonce: This is an 8-octet random value created by the sender of the 549 Map-Request. This nonce will be returned in the Map-Reply. The 550 nonce is used as an index to identify the corresponding Map- 551 Request when a Map-Reply message is received. The nonce MUST be 552 generated by a properly seeded pseudo-random source, see as an 553 example [RFC4086]. 555 Source-EID-AFI: This is the address family of the 'Source EID 556 Address' field. 558 Source EID Address: This is the EID of the source host that 559 originated the packet that caused the Map-Request. When Map- 560 Requests are used for refreshing a Map-Cache entry or for RLOC- 561 Probing, an AFI value 0 is used and this field is of zero length. 563 ITR-RLOC-AFI: This is the address family of the 'ITR-RLOC Address' 564 field that follows this field. 566 ITR-RLOC Address: This is used to give the ETR the option of 567 selecting the destination address from any address family for the 568 Map-Reply message. This address MUST be a routable RLOC address 569 of the sender of the Map-Request message. 571 EID mask-len: This is the mask length for the EID-Prefix. 573 EID-Prefix-AFI: This is the address family of the EID-Prefix 574 according to [AFI] and [RFC8060]. 576 EID-Prefix: This prefix address length is 4 octets for an IPv4 577 address family and 16 octets for an IPv6 address family when the 578 EID-Prefix-AFI is 1 or 2, respectively. For other AFIs [AFI], the 579 address length varies and for the LCAF AFI the format is defined 580 in [RFC8060]. When a Map-Request is sent by an ITR because a data 581 packet is received for a destination where there is no mapping 582 entry, the EID-Prefix is set to the destination IP address of the 583 data packet, and the 'EID mask-len' is set to 32 or 128 for IPv4 584 or IPv6, respectively. When an xTR wants to query a site about 585 the status of a mapping it already has cached, the EID-Prefix used 586 in the Map-Request has the same mask-length as the EID-Prefix 587 returned from the site when it sent a Map-Reply message. 589 Map-Reply Record: When the M-bit is set, this field is the size of a 590 single "Record" in the Map-Reply format. This Map-Reply record 591 contains the EID-to-RLOC mapping entry associated with the Source 592 EID. This allows the ETR that will receive this Map-Request to 593 cache the data if it chooses to do so. 595 5.3. EID-to-RLOC UDP Map-Request Message 597 A Map-Request is sent from an ITR when it needs a mapping for an EID, 598 wants to test an RLOC for reachability, or wants to refresh a mapping 599 before TTL expiration. For the initial case, the destination IP 600 address used for the Map-Request is the data packet's destination 601 address (i.e., the destination EID) that had a mapping cache lookup 602 failure. For the latter two cases, the destination IP address used 603 for the Map-Request is one of the RLOC addresses from the Locator-Set 604 of the Map-Cache entry. The source address is either an IPv4 or IPv6 605 RLOC address, depending on whether the Map-Request is using an IPv4 606 or IPv6 header, respectively. In all cases, the UDP source port 607 number for the Map-Request message is a 16-bit value selected by the 608 ITR/PITR, and the UDP destination port number is set to the well- 609 known destination port number 4342. A successful Map-Reply, which is 610 one that has a nonce that matches an outstanding Map-Request nonce, 611 will update the cached set of RLOCs associated with the EID-Prefix 612 range. 614 One or more Map-Request ('ITR-RLOC-AFI', 'ITR-RLOC-Address') fields 615 MUST be filled in by the ITR. The number of fields (minus 1) encoded 616 MUST be placed in the 'IRC' field. The ITR MAY include all locally 617 configured Locators in this list or just provide one locator address 618 from each address family it supports. If the ITR erroneously 619 provides no ITR-RLOC addresses, the Map-Replier MUST drop the Map- 620 Request. 622 Map-Requests can also be LISP encapsulated using UDP destination 623 port 4342 with a LISP Type value set to "Encapsulated Control 624 Message", when sent from an ITR to a Map-Resolver. Likewise, Map- 625 Requests are LISP encapsulated the same way from a Map-Server to an 626 ETR. Details on Encapsulated Map-Requests and Map-Resolvers can be 627 found in Section 5.8. 629 Map-Requests MUST be rate-limited to 1 per second per EID-prefix. 630 After 10 retransmits without receiving the corresponding Map-Reply 631 MUST wait 30 seconds. 633 An ITR that is configured with mapping database information (i.e., it 634 is also an ETR) MAY optionally include those mappings in a Map- 635 Request. When an ETR configured to accept and verify such 636 "piggybacked" mapping data receives such a Map-Request and it does 637 not have this mapping in the Map-Cache, it MAY originate a "verifying 638 Map-Request", addressed to the map-requesting ITR and the ETR MAY add 639 a Map-Cache entry. If the ETR (when it is an xTR co-located as an 640 ITR) has a Map-Cache entry that matches the "piggybacked" EID and the 641 RLOC is in the Locator-Set for the cached entry, then it MAY send the 642 "verifying Map-Request" directly to the originating Map-Request 643 source. If the RLOC is not in the Locator-Set, then the ETR MUST 644 send the "verifying Map-Request" to the "piggybacked" EID. Doing 645 this forces the "verifying Map-Request" to go through the mapping 646 database system to reach the authoritative source of information 647 about that EID, guarding against RLOC-spoofing in the "piggybacked" 648 mapping data. 650 5.4. Map-Reply Message Format 652 0 1 2 3 653 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 1 654 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 655 |Type=2 |P|E|S| Reserved | Record Count | 656 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 657 | Nonce . . . | 658 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 659 | . . . Nonce | 660 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 661 | | Record TTL | 662 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 663 R | Locator Count | EID mask-len | ACT |A| Reserved | 664 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 665 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 666 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 667 r | EID-Prefix | 668 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 669 | /| Priority | Weight | M Priority | M Weight | 670 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 671 | o | Unused Flags |L|p|R| Loc-AFI | 672 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 673 | \| Locator | 674 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 676 Packet field descriptions: 678 Type: 2 (Map-Reply) 680 P: This is the probe-bit, which indicates that the Map-Reply is in 681 response to a Locator reachability probe Map-Request. The 'Nonce' 682 field MUST contain a copy of the nonce value from the original 683 Map-Request. See RLOC-probing Section 7.1 for more details. When 684 the probe-bit is set to 1 in a Map-Reply message, the A-bit in 685 each EID-record included in the message MUST be set to 1, 686 otherwise MUST be silently discarded. 688 E: This bit indicates that the ETR that sends this Map-Reply message 689 is advertising that the site is enabled for the Echo-Nonce Locator 690 reachability algorithm. See Echo-Nonce [I-D.ietf-lisp-rfc6830bis] 691 for more details. 693 S: This is the Security bit. When set to 1, the following 694 authentication information will be appended to the end of the Map- 695 Reply. The details can be found in [I-D.ietf-lisp-sec]. 697 0 1 2 3 698 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 1 699 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 700 | AD Type | Authentication Data Content . . . | 701 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 703 Reserved: This unassigned field MUST be set to 0 on transmit and 704 MUST be ignored on receipt. 706 Record Count: This is the number of records in this reply message. 707 A record is comprised of that portion of the packet labeled 708 'Record' above and occurs the number of times equal to Record 709 Count. 711 Nonce: This 64-bit value from the Map-Request is echoed in this 712 'Nonce' field of the Map-Reply. 714 Record TTL: This is the time in minutes the recipient of the Map- 715 Reply can store the mapping. If the TTL is 0, the entry MUST be 716 removed from the cache immediately. If the value is 0xffffffff, 717 the recipient can decide locally how long to store the mapping. 719 Locator Count: This is the number of Locator entries in the given 720 Record. A Locator entry comprises what is labeled above as 'Loc'. 721 The Locator count can be 0, indicating that there are no Locators 722 for the EID-Prefix. 724 EID mask-len: This is the mask length for the EID-Prefix. 726 ACT: This 3-bit field describes Negative Map-Reply actions. In any 727 other message type, these bits are set to 0 and ignored on 728 receipt. These bits are used only when the 'Locator Count' field 729 is set to 0. The action bits are encoded only in Map-Reply 730 messages. They are used to tell an ITR or PITR why a empty 731 locator-set was returned from the mapping system and how it stores 732 the map-cache entry. See Section 12.3 for additional information. 734 (0) No-Action: The Map-Cache is kept alive, and no packet 735 encapsulation occurs. 737 (1) Natively-Forward: The packet is not encapsulated or dropped 738 but natively forwarded. 740 (2) Send-Map-Request: The Map-Cache entry is created and flagged 741 that any packet matching this entry invokes sending a Map- 742 Request. 744 (3) Drop/No-Reason: A packet that matches this Map-Cache entry is 745 dropped. An ICMP Destination Unreachable message SHOULD be 746 sent. 748 (4) Drop/Policy-Denied: A packet that matches this Map-Cache 749 entry is dropped. The reason for the Drop action is that a 750 Map-Request for the target-EID is being policy denied by 751 either an xTR or the mapping system. 753 (5) Drop/Authentication-Failure: A packet that matches this Map- 754 Cache entry is dropped. The reason for the Drop action is 755 that a Map-Request for the target-EID fails an authentication 756 verification-check by either an xTR or the mapping system. 758 A: The Authoritative bit MAY only be set to 1 by an ETR. A Map- 759 Server generating Map-Reply messages as a proxy MUST NOT set the 760 A-bit to 1 by an ETR, and not a Map-Server generating Map-Reply 761 messages as a proxy. This bit indicates to requesting ITRs that 762 the Map-Reply was not originated by a LISP node managed at the 763 site that owns the EID-Prefix. 765 Map-Version Number: When this 12-bit value is non-zero, the Map- 766 Reply sender is informing the ITR what the version number is for 767 the EID record contained in the Map-Reply. The ETR can allocate 768 this number internally but MUST coordinate this value with other 769 ETRs for the site. When this value is 0, there is no versioning 770 information conveyed. The Map-Version Number can be included in 771 Map-Request and Map-Register messages. See Map-Versioning 772 [I-D.ietf-lisp-6834bis] for more details. 774 EID-Prefix-AFI: Address family of the EID-Prefix according to [AFI] 775 and [RFC8060]. 777 EID-Prefix: This prefix is 4 octets for an IPv4 address family and 778 16 octets for an IPv6 address family. 780 Priority: Each RLOC is assigned a unicast Priority. Lower values 781 are more preferable. When multiple RLOCs have the same Priority, 782 they may be used in a load-split fashion. A value of 255 means 783 the RLOC MUST NOT be used for unicast forwarding. 785 Weight: When priorities are the same for multiple RLOCs, the Weight 786 indicates how to balance unicast traffic between them. Weight is 787 encoded as a relative weight of total unicast packets that match 788 the mapping entry. For example, if there are 4 Locators in a 789 Locator-Set, where the Weights assigned are 30, 20, 20, and 10, 790 the first Locator will get 37.5% of the traffic, the 2nd and 3rd 791 Locators will each get 25% of the traffic, and the 4th Locator 792 will get 12.5% of the traffic. If all Weights for a Locator-Set 793 are equal, the receiver of the Map-Reply will decide how to load- 794 split the traffic. See RLOC-hashing [I-D.ietf-lisp-rfc6830bis] 795 for a suggested hash algorithm to distribute the load across 796 Locators with the same Priority and equal Weight values. 798 M Priority: Each RLOC is assigned a multicast Priority used by an 799 ETR in a receiver multicast site to select an ITR in a source 800 multicast site for building multicast distribution trees. A value 801 of 255 means the RLOC MUST NOT be used for joining a multicast 802 distribution tree. For more details, see [RFC6831]. 804 M Weight: When priorities are the same for multiple RLOCs, the 805 Weight indicates how to balance building multicast distribution 806 trees across multiple ITRs. The Weight is encoded as a relative 807 weight (similar to the unicast Weights) of the total number of 808 trees built to the source site identified by the EID-Prefix. If 809 all Weights for a Locator-Set are equal, the receiver of the Map- 810 Reply will decide how to distribute multicast state across ITRs. 811 For more details, see [RFC6831]. 813 Unused Flags: These are set to 0 when sending and ignored on 814 receipt. 816 L: When this bit is set, the Locator is flagged as a local Locator to 817 the ETR that is sending the Map-Reply. When a Map-Server is doing 818 proxy Map-Replying for a LISP site, the L-bit is set to 0 for all 819 Locators in this Locator-Set. 821 p: When this bit is set, an ETR informs the RLOC-Probing ITR that the 822 locator address for which this bit is set is the one being RLOC- 823 probed and may be different from the source address of the Map- 824 Reply. An ITR that RLOC-probes a particular Locator MUST use this 825 Locator for retrieving the data structure used to store the fact 826 that the Locator is reachable. The p-bit is set for a single 827 Locator in the same Locator-Set. If an implementation sets more 828 than one p-bit erroneously, the receiver of the Map-Reply MUST 829 select the first set p-bit Locator. The p-bit MUST NOT be set for 830 Locator-Set records sent in Map-Request and Map-Register messages. 832 R: This is set when the sender of a Map-Reply has a route to the 833 Locator in the Locator data record. This receiver may find this 834 useful to know if the Locator is up but not necessarily reachable 835 from the receiver's point of view. See also EID-Reachability 836 Section 7.1 for another way the R-bit may be used. 838 Locator: This is an IPv4 or IPv6 address (as encoded by the 'Loc- 839 AFI' field) assigned to an ETR and used by an ITR as a destination 840 RLOC address in the outer header of a LISP encapsulated packet. 841 Note that the destination RLOC address of a LISP encapsulated 842 packet MAY be an anycast address. A source RLOC of a LISP 843 encapsulated packet can be an anycast address as well. The source 844 or destination RLOC MUST NOT be the broadcast address 845 (255.255.255.255 or any subnet broadcast address known to the 846 router) and MUST NOT be a link-local multicast address. The 847 source RLOC MUST NOT be a multicast address. The destination RLOC 848 SHOULD be a multicast address if it is being mapped from a 849 multicast destination EID. 851 Map-Reply MUST be rate-limited, it is RECOMMENDED that a Map-Reply 852 for the same destination RLOC be sent no more than one packets per 3 853 seconds. 855 The Record format, as defined here, is used both in the Map-Reply and 856 Map-Register messages, this includes all the field definitions. 858 5.5. EID-to-RLOC UDP Map-Reply Message 860 A Map-Reply returns an EID-Prefix with a mask-length that is less 861 than or equal to the EID being requested. The EID being requested is 862 either from the destination field of an IP header of a Data-Probe or 863 the EID record of a Map-Request. The RLOCs in the Map-Reply are 864 routable IP addresses of all ETRs for the LISP site. Each RLOC 865 conveys status reachability but does not convey path reachability 866 from a requester's perspective. Separate testing of path 867 reachability is required. See RLOC-reachability Section 7.1 for 868 details. 870 Note that a Map-Reply MAY contain different EID-Prefix granularity 871 (prefix + mask-length) than the Map-Request that triggers it. This 872 might occur if a Map-Request were for a prefix that had been returned 873 by an earlier Map-Reply. In such a case, the requester updates its 874 cache with the new prefix information and granularity. For example, 875 a requester with two cached EID-Prefixes that are covered by a Map- 876 Reply containing one less-specific prefix replaces the entry with the 877 less-specific EID-Prefix. Note that the reverse, replacement of one 878 less-specific prefix with multiple more-specific prefixes, can also 879 occur, not by removing the less-specific prefix but rather by adding 880 the more-specific prefixes that, during a lookup, will override the 881 less-specific prefix. 883 When an EID moves out of a LISP site [I-D.ietf-lisp-eid-mobility], 884 the database mapping system may have overlapping EID-prefixes. Or 885 when a LISP site is configured with multiple sets of ETRs that 886 support different EID-prefix mask-lengths, the database mapping 887 system may have overlapping EID-prefixes. When overlapping EID- 888 prefixes exist, a Map-Request with an EID that best matches any EID- 889 Prefix MUST be returned in a single Map-Reply message. For instance, 890 if an ETR had database mapping entries for EID-Prefixes: 892 2001:db8::/32 893 2001:db8:1::/48 894 2001:db8:1:1::/64 895 2001:db8:1:2::/64 897 A Map-Request for EID 2001:db8:1:1::1 would cause a Map-Reply with a 898 record count of 1 to be returned with a mapping record EID-Prefix of 899 2001:db8:1:1::/64. 901 A Map-Request for EID 2001:db8:1:5::5 would cause a Map-Reply with a 902 record count of 3 to be returned with mapping records for EID- 903 Prefixes 2001:db8:1::/48, 2001:db8:1:1::/64, 2001:db8:1:2::/64, 904 filling out the /48 with more-specifics that exist in the mapping 905 system. 907 Note that not all overlapping EID-Prefixes need to be returned but 908 only the more-specific entries (note that in the second example above 909 2001:db8::/32 was not returned for requesting EID 2001:db8:1:5::5) 910 for the matching EID-Prefix of the requesting EID. When more than 911 one EID-Prefix is returned, all SHOULD use the same Time to Live 912 value so they can all time out at the same time. When a more- 913 specific EID-Prefix is received later, its Time to Live value in the 914 Map-Reply record can be stored even when other less-specific entries 915 exist. When a less-specific EID-Prefix is received later, its Map- 916 Cache expiration time SHOULD be set to the minimum expiration time of 917 any more-specific EID-Prefix in the Map-Cache. This is done so the 918 integrity of the EID-Prefix set is wholly maintained and so no more- 919 specific entries are removed from the Map-Cache while keeping less- 920 specific entries. 922 For scalability, it is expected that aggregation of EID addresses 923 into EID-Prefixes will allow one Map-Reply to satisfy a mapping for 924 the EID addresses in the prefix range, thereby reducing the number of 925 Map-Request messages. 927 Map-Reply records can have an empty Locator-Set. A Negative Map- 928 Reply is a Map-Reply with an empty Locator-Set. Negative Map-Replies 929 convey special actions by the sender to the ITR or PITR that have 930 solicited the Map-Reply. There are two primary applications for 931 Negative Map-Replies. The first is for a Map-Resolver to instruct an 932 ITR or PITR when a destination is for a LISP site versus a non-LISP 933 site, and the other is to source quench Map-Requests that are sent 934 for non-allocated EIDs. 936 For each Map-Reply record, the list of Locators in a Locator-Set MUST 937 be sorted in order of ascending IP address where an IPv4 locator 938 address is considered numerically 'less than' an IPv6 locator 939 address. 941 When sending a Map-Reply message, the destination address is copied 942 from one of the 'ITR-RLOC' fields from the Map-Request. The ETR can 943 choose a locator address from one of the address families it 944 supports. For Data-Probes, the destination address of the Map-Reply 945 is copied from the source address of the Data-Probe message that is 946 invoking the reply. The source address of the Map-Reply is one of 947 the local IP addresses chosen, to allow Unicast Reverse Path 948 Forwarding (uRPF) checks to succeed in the upstream service provider. 949 The destination port of a Map-Reply message is copied from the source 950 port of the Map-Request or Data-Probe, and the source port of the 951 Map-Reply message is set to the well-known UDP port 4342. 953 5.6. Map-Register Message Format 955 This section specifies the encoding format for the Map-Register 956 message. The message is sent in UDP with a destination UDP port of 957 4342 and a randomly selected UDP source port number. 959 The fields below are used in multiple control messages. They are 960 defined for Map-Register, Map-Notify and Map-Notify-Ack message 961 types. 963 The Map-Register message format is: 965 0 1 2 3 966 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 1 967 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 968 |Type=3 |P|S|I| Reserved |E|T|a|R|M| Record Count | 969 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 970 | Nonce . . . | 971 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 972 | . . . Nonce | 973 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 974 | Key ID | Algorithm ID | Authentication Data Length | 975 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 976 ~ Authentication Data ~ 977 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 978 | | Record TTL | 979 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 980 R | Locator Count | EID mask-len | ACT |A| Reserved | 981 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 982 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 983 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 984 r | EID-Prefix | 985 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 986 | /| Priority | Weight | M Priority | M Weight | 987 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 988 | o | Unused Flags |L|p|R| Loc-AFI | 989 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 990 | \| Locator | 991 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 993 Packet field descriptions: 995 Type: 3 (Map-Register) 997 P: This is the proxy Map-Reply bit. When set to 1, the ETR sending 998 the Map-Register message is requesting the Map-Server to proxy a 999 Map-Reply. The Map-Server will send non-authoritative Map-Replies 1000 on behalf of the ETR. 1002 S: This is the security-capable bit. When set, the procedures from 1003 [I-D.ietf-lisp-sec] are supported. 1005 I: This is the ID-present bit. This bit is set to 1 to indicate that 1006 a 128 bit xTR-ID and a 64 bit Site-ID fields are present at the 1007 end of the Map-Register message. If an xTR is configured with an 1008 xTR-ID and Site-ID, it MUST set the I bit to 1 and include its 1009 xTR-ID and Site-ID in the Map-Register messages it generates. The 1010 combination of Site-ID plus xTR-ID uniquely identifies an xTR in a 1011 LISP domain and serves to track its last seen nonce. 1013 Reserved: This unassigned field MUST be set to 0 on transmit and 1014 MUST be ignored on receipt. 1016 E: This is the Map-Register EID-notify bit. This is used by a First- 1017 Hop-Router (FHR) which discovers a dynamic-EID. This EID-notify 1018 based Map-Register is sent by the FHR to the same site xTR that 1019 propogates the Map-Register to the mapping system. The site xTR 1020 keeps state to later Map-Notify the FHR after the EID has moves 1021 away. See [I-D.ietf-lisp-eid-mobility] for a detailed use-case. 1023 T: This is the use-TTL for timeout bit. When set to 1, the xTR wants 1024 the Map-Server to time out registrations based on the value in the 1025 "Record TTL" field of this message. Otherwise, the default 1026 timeout described in Section 8.2 is used. 1028 a: This is the merge-request bit. When set to 1, the xTR requests to 1029 merge RLOC-records from different xTRs registering the same EID- 1030 record. See signal-free multicast [RFC8378] for one use case 1031 example. 1033 R: This reserved and unassigned bit MUST be set to 0 on transmit and 1034 MUST be ignored on receipt. 1036 M: This is the want-map-notify bit. When set to 1, an ETR is 1037 requesting a Map-Notify message to be returned in response to 1038 sending a Map-Register message. The Map-Notify message sent by a 1039 Map-Server is used to acknowledge receipt of a Map-Register 1040 message. 1042 Record Count: This is the number of records in this Map-Register 1043 message. A record is comprised of that portion of the packet 1044 labeled 'Record' above and occurs the number of times equal to 1045 Record Count. 1047 Nonce: This 8-octet 'Nonce' field is incremented each time a Map- 1048 Register message is sent. When a Map-Register acknowledgement is 1049 requested, the nonce is returned by Map-Servers in Map-Notify 1050 messages. Since the entire Map-Register message is authenticated, 1051 the 'Nonce' field serves to protect against Map-Register replay 1052 attacks. An ETR that registers to the mapping system SHOULD store 1053 the last nonce sent in persistent storage so when it restarts it 1054 can continue using an incrementing nonce. If the ETR cannot 1055 support saving the nonce, then when it restarts it MUST use a new 1056 authentication key to register to the mapping system. A Map- 1057 Server MUST track and save in persistent storage the last nonce 1058 received for each ETR xTR-ID and key pair. If a Map-Register is 1059 received with a nonce value that is not greater than the saved 1060 nonce, it MUST drop the Map-Register message and SHOULD log the 1061 fact a replay attack could have occurred. 1063 Key ID: A key-id value that identifies a pre-shared secret between 1064 an ETR and a Map-Server. Per-message keys are derived from the 1065 pre-shared secret to authenticate the origin and protect the 1066 integrity of the Map-Register. The Key ID allows to rotate 1067 between multiple pre-shared secrets in a non disruptive way. The 1068 pre-shared secret MUST be unique per each LISP "Site-ID" 1070 Algorithm ID: This field identifies the Key Derivation Function 1071 (KDF) and Message Authentication Code (MAC) algorithms used to 1072 derive the key and to compute the Authentication Data of a Map- 1073 Register. This 8-bit field identifies the KDF and MAC algorithm 1074 pair. See Section 12.5 for codepoint assignments. 1076 Authentication Data Length: This is the length in octets of the 1077 'Authentication Data' field that follows this field. The length 1078 of the 'Authentication Data' field is dependent on the MAC 1079 algorithm used. The length field allows a device that doesn't 1080 know the MAC algorithm to correctly parse the packet. 1082 Authentication Data: This is the output of the MAC algorithm placed 1083 in this field after the MAC computation. The MAC output is 1084 computed as follows: 1086 1: The KDF algorithm is identified by the field 'Algorithm ID' 1087 according to the table in Section 12.5. Implementations of 1088 this specification MUST implement HMAC-SHA-256-128 and SHOULD 1089 implement HMAC-SHA256-128+HKDF-SHA256 [RFC4868]. 1091 2: The MAC algorithm is identified by the field 'Algorithm ID' 1092 according to the table in Section 12.5. 1094 3: The pre-shared secret used to derive the per-message key is 1095 represented by PSK[Key ID], that is the pre-shared secret 1096 identified by the 'Key ID'. 1098 4: The derived per-message key is computed as: per-msg- 1099 key=KDF(nonce+s+PSK[Key ID]). Where the nonce is the value in 1100 the Nonce field of the Map-Register and 's' is a string equal 1101 to "Map-Register Authentication". For those Algorithm IDs 1102 defined in Section 12.5 that specify a 'none' KDF, the per- 1103 message key is computed as: per-msg-key = PSK[Key ID]. This 1104 means that the same key is used across multiple protocol 1105 messages. 1107 5: The MAC output is computed using the MAC algorithm and the 1108 per-msg-key over the entire Map-Register payload (from and 1109 including the LISP message type field through the end of the 1110 last RLOC record) with the authenticated data field preset to 1111 0. 1113 The definition of the rest of the Map-Register can be found in EID- 1114 record description in Section 5.4. When the I-bit is set, the 1115 following fields are added to the end of the Map-Register message: 1117 xTR-ID: xTR-ID is a 128 bit field at the end of the Map-Register 1118 message, starting after the final Record in the message. The xTR- 1119 ID is used to uniquely identify a xTR. The same xTR-ID value MUST 1120 NOT be used in two different xTRs in the scope of the Site-ID. 1122 Site-ID: Site-ID is a 64 bit field at the end of the Map- Register 1123 message, following the xTR-ID. Site-ID is used to uniquely 1124 identify to which site the xTR that sent the message belongs. 1125 This document does not specify a strict meaning for the Site-ID 1126 field. Informally it provides an indication that a group of xTRs 1127 have some relation, either administratively, topologically or 1128 otherwise. 1130 5.7. Map-Notify/Map-Notify-Ack Message Format 1132 This section specifies the encoding format for the Map-Notify and 1133 Map-Notify-Ack messages. The messages are sent inside a UDP packet 1134 with source and destination UDP ports equal to 4342. 1136 The Map-Notify and Map-Notify-Ack message formats are: 1138 0 1 2 3 1139 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 1140 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1141 |Type=4/5| Reserved | Record Count | 1142 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1143 | Nonce . . . | 1144 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1145 | . . . Nonce | 1146 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1147 | Key ID | Algorithm ID | Authentication Data Length | 1148 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1149 ~ Authentication Data ~ 1150 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1151 | | Record TTL | 1152 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1153 R | Locator Count | EID mask-len | ACT |A| Reserved | 1154 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1155 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 1156 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1157 r | EID-Prefix | 1158 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1159 | /| Priority | Weight | M Priority | M Weight | 1160 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1161 | o | Unused Flags |L|p|R| Loc-AFI | 1162 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1163 | \| Locator | 1164 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1166 Packet field descriptions: 1168 Type: 4/5 (Map-Notify/Map-Notify-Ack) 1170 The Map-Notify message has the same contents as a Map-Register 1171 message. See the Map-Register section for field descriptions and the 1172 Map-Reply section for EID-record and RLOC-record descriptions. 1174 The fields of the Map-Notify are copied from the corresponding Map- 1175 Register to acknowledge its correct processing. In the Map-Notfiy, 1176 the 'Authentication Data' field is recomputed according to the 1177 procedure defined in the previous section. For an unsolicited Map- 1178 Notify, the fields of a Map-Notify used for publish/subscribe are 1179 specified in [I-D.ietf-lisp-pubsub]. 1181 After sending a Map-Register, if a Map-Notify is not received after 1 1182 second the transmitter MUST re-transmit the original Map-Register 1183 with an exponential backoff (base of 2, that is, the next backoff 1184 timeout interval is doubled), the maximum backoff is 1 minute. 1186 The Map-Notify-Ack message has the same contents as a Map-Notify 1187 message. It is used to acknowledge the receipt of a Map-Notify and 1188 for the sender to stop retransmitting a Map-Notify with the same 1189 nonce and the authentication data validates. The fields of the Map- 1190 Notify-Ack are copied from the corresponding Map-Notify message to 1191 acknowledge its correct processing. The 'Authentication Data' field 1192 is recomputed according to the procedure defined in the previous 1193 section. 1195 A Map-Server sends an unsolicited Map-Notify message (one that is not 1196 used as an acknowledgment to a Map-Register message) in only 1197 conformance the Congestion Control And Relability Guideline sections 1198 of [RFC8085]. A Map-Notify is retransmitted until a Map-Notify-Ack 1199 is received by the Map-Server with the same nonce used in the Map- 1200 Notify message. If a Map-Notify-Ack is never received by the Map- 1201 Server, it issues a log message. An implementation SHOULD retransmit 1202 up to 3 times at 3 second retransmission intervals, after which time 1203 the retransmission interval is exponentially backed-off (base of 2, 1204 that is, the next backoff timeout interval is doubled) for another 3 1205 retransmission attempts. 1207 Upon reception of Map-Register, Map-Notify or Map-Notifiy-Ack, the 1208 receiver verifies the authentication data. 1210 5.8. Encapsulated Control Message Format 1212 An Encapsulated Control Message (ECM) is used to encapsulate control 1213 packets sent between xTRs and the mapping database system or internal 1214 to the mapping database system. 1216 0 1 2 3 1217 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 1218 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1219 / | IPv4 or IPv6 Header | 1220 OH | (uses RLOC addresses) | 1221 \ | | 1222 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1223 / | Source Port = xxxx | Dest Port = 4342 | 1224 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1225 \ | UDP Length | UDP Checksum | 1226 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1227 LISP |Type=8 |S|D|R|R| Reserved | 1228 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1229 / | IPv4 or IPv6 Header | 1230 IH | (uses RLOC or EID addresses) | 1231 \ | | 1232 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1233 / | Source Port = xxxx | Dest Port = yyyy | 1234 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1235 \ | UDP Length | UDP Checksum | 1236 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1237 LCM | LISP Control Message | 1238 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1240 Packet header descriptions: 1242 OH: The outer IPv4 or IPv6 header, which uses RLOC addresses in the 1243 source and destination header address fields. 1245 UDP: The outer UDP header with destination port 4342. The source 1246 port is randomly allocated. The checksum field MUST be non- 1247 zero. 1249 LISP: Type 8 is defined to be a "LISP Encapsulated Control Message", 1250 and what follows is either an IPv4 or IPv6 header as encoded by 1251 the first 4 bits after the 'Reserved' field. 1253 Type: 8 (Encapsulated Control Message (ECM)) 1255 S: This is the Security bit. When set to 1, the field following 1256 the 'Reserved' field will have the following Authentication 1257 Data format and follow the procedures from [I-D.ietf-lisp-sec]. 1259 0 1 2 3 1260 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 1261 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1262 | AD Type | Authentication Data Content . . . | 1263 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1265 D: This is the DDT-bit. When set to 1, the sender is requesting a 1266 Map-Referral message to be returned. The details of this 1267 procedure are described in [RFC8111]. 1269 R: This reserved and unassigned bit MUST be set to 0 on transmit 1270 and MUST be ignored on receipt. 1272 IH: The inner IPv4 or IPv6 header, which can use either RLOC or EID 1273 addresses in the header address fields. When a Map-Request is 1274 encapsulated in this packet format, the destination address in 1275 this header is an EID. 1277 UDP: The inner UDP header, where the port assignments depend on the 1278 control packet being encapsulated. When the control packet is 1279 a Map-Request or Map-Register, the source port is selected by 1280 the ITR/PITR and the destination port is 4342. When the 1281 control packet is a Map-Reply, the source port is 4342 and the 1282 destination port is assigned from the source port of the 1283 invoking Map-Request. Port number 4341 MUST NOT be assigned to 1284 either port. The checksum field MUST be non-zero. 1286 LCM: The format is one of the control message formats described in 1287 Section 5. Map-Request messages are allowed to be Control- 1288 Plane (ECM) encapsulated. When Map-Requests are sent for RLOC- 1289 Probing purposes (i.e. the probe-bit is set), they MUST NOT be 1290 sent inside Encapsulated Control Messages. PIM Join/Prune 1291 messages [RFC6831] are also allowed to be Control-Plane (ECM) 1292 encapsulated. 1294 6. Changing the Contents of EID-to-RLOC Mappings 1296 In the LISP architecture ITRs/PITRs use a local Map-Cache to store 1297 EID-to-RLOC mappings for forwarding. When an ETR updates a mapping a 1298 mechanism is required to inform ITRs/PITRs that are using such 1299 mappings. 1301 The LISP Data-Plane defines several mechanism to update mappings 1302 [I-D.ietf-lisp-rfc6830bis]. This document specifies the Solicit-Map 1303 Request (SMR), a Control-Plane push-based mechanism. An additional 1304 Control-Plane mechanism based on the Publish/subscribe paradigm is 1305 specified in [I-D.ietf-lisp-pubsub]. 1307 6.1. Solicit-Map-Request (SMR) 1309 Soliciting a Map-Request is a selective way for ETRs, at the site 1310 where mappings change, to control the rate they receive requests for 1311 Map-Reply messages. SMRs are also used to tell remote ITRs to update 1312 the mappings they have cached. 1314 Since ETRs are not required to keep track of remote ITRs that have 1315 cached their mappings, they do not know which ITRs need to have their 1316 mappings updated. As a result, an ETR will solicit Map-Requests 1317 (called an SMR message) to those sites to which it has been sending 1318 LISP encapsulated data packets for the last minute. As a result, 1319 when an ETR is also acting as ITR, it will send an SMR to an ITR to 1320 which it has recently sent encapsulated data. 1322 An SMR message is simply a bit set in a Map-Request message. An ITR 1323 or PITR will send a Map-Request when they receive an SMR message. 1324 Both the SMR sender and the SMR responder MUST rate-limit these 1325 messages. It is RECOMMENDED that the SMR sender rate-limits Map- 1326 Request for the same destination RLOC to no more than one packet per 1327 3 seconds. It is RECOMMENDED that the SMR responder rate-limits Map- 1328 Request for the same EID-Prefix to no more than once per 3 seconds. 1330 For security reasons, an ITR MUST NOT process unsolicited Map- 1331 Replies. To avoid Map-Cache entry corruption by a third party, a 1332 sender of an SMR message MUST be verified. If an ITR receives an SMR 1333 message and the source is not in the Locator-Set for the stored Map- 1334 Cache entry, then the responding Map-Request MUST be sent with an EID 1335 destination to the mapping database system. Since the mapping 1336 database system is a more secure way to reach an authoritative ETR, 1337 it will deliver the Map-Request to the authoritative source of the 1338 mapping data. Please note that this procedure does not result in 1339 cryptographic or strongly authenticated verification. 1341 When an ITR receives an SMR-based Map-Request for which it does not 1342 have a cached mapping for the EID in the SMR message, it SHOULD NOT 1343 send an SMR-invoked Map-Request. This scenario can occur when an ETR 1344 sends SMR messages to all Locators in the Locator-Set it has stored 1345 in its Map-Cache but the remote ITRs that receive the SMR may not be 1346 sending packets to the site. There is no point in updating the ITRs 1347 until they need to send, in which case they will send Map-Requests to 1348 obtain a Map-Cache entry. 1350 7. Routing Locator Reachability 1352 This document defines several Control-Plane mechanisms for 1353 determining RLOC reachability. Please note that additional Data- 1354 Plane reachability mechanisms are defined in 1355 [I-D.ietf-lisp-rfc6830bis]. 1357 1. An ITR may receive an ICMP Network Unreachable or Host 1358 Unreachable message for an RLOC it is using. This indicates that 1359 the RLOC is likely down. Note that trusting ICMP messages may 1360 not be desirable, but neither is ignoring them completely. 1361 Implementations are encouraged to follow current best practices 1362 in treating these conditions [I-D.ietf-opsec-icmp-filtering]. 1364 2. When an ITR participates in the routing protocol that operates in 1365 the underlay routing system, it can determine that an RLOC is 1366 down when no Routing Information Base (RIB) entry exists that 1367 matches the RLOC IP address. 1369 3. An ITR may receive an ICMP Port Unreachable message from a 1370 destination host. This occurs if an ITR attempts to use 1371 interworking [RFC6832] and LISP-encapsulated data is sent to a 1372 non-LISP-capable site. 1374 4. An ITR may receive a Map-Reply from an ETR in response to a 1375 previously sent Map-Request. The RLOC source of the Map-Reply is 1376 likely up, since the ETR was able to send the Map-Reply to the 1377 ITR. 1379 5. An ITR/ETR pair can use the 'RLOC-Probing' mechanism described 1380 below. 1382 When ITRs receive ICMP Network Unreachable or Host Unreachable 1383 messages as a method to determine unreachability, they will refrain 1384 from using Locators that are described in Locator lists of Map- 1385 Replies. However, using this approach is unreliable because many 1386 network operators turn off generation of ICMP Destination Unreachable 1387 messages. 1389 If an ITR does receive an ICMP Network Unreachable or Host 1390 Unreachable message, it MAY originate its own ICMP Destination 1391 Unreachable message destined for the host that originated the data 1392 packet the ITR encapsulated. 1394 This assumption does create a dependency: Locator unreachability is 1395 detected by the receipt of ICMP Host Unreachable messages. When a 1396 Locator has been determined to be unreachable, it is not used for 1397 active traffic; this is the same as if it were listed in a Map-Reply 1398 with Priority 255. 1400 The ITR can test the reachability of the unreachable Locator by 1401 sending periodic Requests. Both Requests and Replies MUST be rate- 1402 limited, see Section 5.3 and Section 5.4 for information about rate- 1403 limiting. Locator reachability testing is never done with data 1404 packets, since that increases the risk of packet loss for end-to-end 1405 sessions. 1407 7.1. RLOC-Probing Algorithm 1409 RLOC-Probing is a method that an ITR or PITR can use to determine the 1410 reachability status of one or more Locators that it has cached in a 1411 Map-Cache entry. The probe-bit of the Map-Request and Map-Reply 1412 messages is used for RLOC-Probing. 1414 RLOC-Probing is done in the control plane on a timer basis, where an 1415 ITR or PITR will originate a Map-Request destined to a locator 1416 address from one of its own locator addresses. A Map-Request used as 1417 an RLOC-probe is NOT encapsulated and NOT sent to a Map-Server or to 1418 the mapping database system as one would when requesting mapping 1419 data. The EID record encoded in the Map-Request is the EID-Prefix of 1420 the Map-Cache entry cached by the ITR or PITR. The ITR MAY include a 1421 mapping data record for its own database mapping information that 1422 contains the local EID-Prefixes and RLOCs for its site. RLOC-probes 1423 are sent periodically using a jittered timer interval. 1425 When an ETR receives a Map-Request message with the probe-bit set, it 1426 returns a Map-Reply with the probe-bit set. The source address of 1427 the Map-Reply is set to the IP address of the outgoing interface the 1428 Map-Reply destination address routes to. The Map-Reply SHOULD 1429 contain mapping data for the EID-Prefix contained in the Map-Request. 1430 This provides the opportunity for the ITR or PITR that sent the RLOC- 1431 probe to get mapping updates if there were changes to the ETR's 1432 database mapping entries. 1434 There are advantages and disadvantages of RLOC-Probing. The main 1435 benefit of RLOC-Probing is that it can handle many failure scenarios 1436 allowing the ITR to determine when the path to a specific Locator is 1437 reachable or has become unreachable, thus providing a robust 1438 mechanism for switching to using another Locator from the cached 1439 Locator. RLOC-Probing can also provide rough Round-Trip Time (RTT) 1440 estimates between a pair of Locators, which can be useful for network 1441 management purposes as well as for selecting low delay paths. The 1442 major disadvantage of RLOC-Probing is in the number of control 1443 messages required and the amount of bandwidth used to obtain those 1444 benefits, especially if the requirement for failure detection times 1445 is very small. 1447 8. Interactions with Other LISP Components 1449 8.1. ITR EID-to-RLOC Mapping Resolution 1451 An ITR is configured with one or more Map-Resolver addresses. These 1452 addresses are "Locators" (or RLOCs) and MUST be routable on the 1453 underlying core network; they MUST NOT need to be resolved through 1454 LISP EID-to-RLOC mapping, as that would introduce a circular 1455 dependency. When using a Map-Resolver, an ITR does not need to 1456 connect to any other database mapping system. 1458 An ITR sends an Encapsulated Map-Request to a configured Map-Resolver 1459 when it needs an EID-to-RLOC mapping that is not found in its local 1460 Map-Cache. Using the Map-Resolver greatly reduces both the 1461 complexity of the ITR implementation and the costs associated with 1462 its operation. 1464 In response to an Encapsulated Map-Request, the ITR can expect one of 1465 the following: 1467 o An immediate Negative Map-Reply (with action code of "Natively- 1468 Forward", 15-minute Time to Live (TTL)) from the Map-Resolver if 1469 the Map-Resolver can determine that the requested EID does not 1470 exist. The ITR saves the EID-Prefix returned in the Map-Reply in 1471 its cache, marks it as non-LISP-capable, and knows not to attempt 1472 LISP encapsulation for destinations matching it. 1474 o A Negative Map-Reply, with action code of "Natively-Forward", from 1475 a Map-Server that is authoritative (within the LISP deployment 1476 Section 1.1) for an EID-Prefix that matches the requested EID but 1477 that does not have an actively registered, more-specific EID- 1478 prefix. In this case, the requested EID is said to match a "hole" 1479 in the authoritative EID-Prefix. If the requested EID matches a 1480 more-specific EID-Prefix that has been delegated by the Map-Server 1481 but for which no ETRs are currently registered, a 1-minute TTL is 1482 returned. If the requested EID matches a non-delegated part of 1483 the authoritative EID-Prefix, then it is not a LISP EID and a 1484 15-minute TTL is returned. See Section 8.2 for discussion of 1485 aggregate EID-Prefixes and details of Map-Server EID-Prefix 1486 matching. 1488 o A LISP Map-Reply from the ETR that owns the EID-to-RLOC mapping or 1489 possibly from a Map-Server answering on behalf of the ETR. See 1490 Section 8.4 for more details on Map-Resolver message processing. 1492 Note that an ITR may be configured to both use a Map-Resolver and to 1493 participate in a LISP-ALT logical network. In such a situation, the 1494 ITR SHOULD send Map-Requests through the ALT network for any EID- 1495 Prefix learned via ALT BGP. Such a configuration is expected to be 1496 very rare, since there is little benefit to using a Map-Resolver if 1497 an ITR is already using LISP-ALT. There would be, for example, no 1498 need for such an ITR to send a Map-Request to a possibly non-existent 1499 EID (and rely on Negative Map-Replies) if it can consult the ALT 1500 database to verify that an EID-Prefix is present before sending that 1501 Map-Request. 1503 8.2. EID-Prefix Configuration and ETR Registration 1505 An ETR publishes its EID-Prefixes on a Map-Server by sending LISP 1506 Map-Register messages. A Map-Register message includes 1507 authentication data, so prior to sending a Map-Register message, the 1508 ETR and Map-Server MUST be configured with a pre-shared secret used 1509 to derive Map-Register authentication keys. A Map-Server's 1510 configuration SHOULD also include a list of the EID-Prefixes for 1511 which each ETR is authoritative. Upon receipt of a Map-Register from 1512 an ETR, a Map-Server accepts only EID-Prefixes that are configured 1513 for that ETR. Failure to implement such a check would leave the 1514 mapping system vulnerable to trivial EID-Prefix hijacking attacks. 1516 In addition to the set of EID-Prefixes defined for each ETR that may 1517 register, a Map-Server is typically also configured with one or more 1518 aggregate prefixes that define the part of the EID numbering space 1519 assigned to it. When LISP-ALT is the database in use, aggregate EID- 1520 Prefixes are implemented as discard routes and advertised into ALT 1521 BGP. The existence of aggregate EID-Prefixes in a Map-Server's 1522 database means that it may receive Map Requests for EID-Prefixes that 1523 match an aggregate but do not match a registered prefix; Section 8.3 1524 describes how this is handled. 1526 Map-Register messages are sent periodically from an ETR to a Map- 1527 Server with a suggested interval between messages of one minute. A 1528 Map-Server SHOULD time out and remove an ETR's registration if it has 1529 not received a valid Map-Register message within the past 1530 three minutes. When first contacting a Map-Server after restart or 1531 changes to its EID-to-RLOC database mappings, an ETR MAY initially 1532 send Map-Register messages at an increased frequency, up to one every 1533 20 seconds. This "quick registration" period is limited to 1534 five minutes in duration. 1536 An ETR MAY request that a Map-Server explicitly acknowledge receipt 1537 and processing of a Map-Register message by setting the "want-map- 1538 notify" (M-bit) flag. A Map-Server that receives a Map-Register with 1539 this flag set will respond with a Map-Notify message. Typical use of 1540 this flag by an ETR would be to set it for Map-Register messages sent 1541 during the initial "quick registration" with a Map-Server but then 1542 set it only occasionally during steady-state maintenance of its 1543 association with that Map-Server. Note that the Map-Notify message 1544 is sent to UDP destination port 4342, not to the source port 1545 specified in the original Map-Register message. 1547 Note that a one-minute minimum registration interval during 1548 maintenance of an ETR-Map-Server association places a lower bound on 1549 how quickly and how frequently a mapping database entry can be 1550 updated. This may have implications for what sorts of mobility can 1551 be supported directly by the mapping system; shorter registration 1552 intervals or other mechanisms might be needed to support faster 1553 mobility in some cases. For a discussion on one way that faster 1554 mobility may be implemented for individual devices, please see 1555 [I-D.ietf-lisp-mn]. 1557 An ETR MAY also request, by setting the "proxy Map-Reply" flag 1558 (P-bit) in the Map-Register message, that a Map-Server answer Map- 1559 Requests instead of forwarding them to the ETR. See Section 7.1 for 1560 details on how the Map-Server sets certain flags (such as those 1561 indicating whether the message is authoritative and how returned 1562 Locators SHOULD be treated) when sending a Map-Reply on behalf of an 1563 ETR. When an ETR requests proxy reply service, it SHOULD include all 1564 RLOCs for all ETRs for the EID-Prefix being registered, along with 1565 the routable flag ("R-bit") setting for each RLOC. The Map-Server 1566 includes all of this information in Map-Reply messages that it sends 1567 on behalf of the ETR. This differs from a non-proxy registration, 1568 since the latter need only provide one or more RLOCs for a Map-Server 1569 to use for forwarding Map-Requests; the registration information is 1570 not used in Map-Replies, so it being incomplete is not incorrect. 1572 An ETR that uses a Map-Server to publish its EID-to-RLOC mappings 1573 does not need to participate further in the mapping database 1574 protocol(s). When using a LISP-ALT mapping database, for example, 1575 this means that the ETR does not need to implement GRE or BGP, which 1576 greatly simplifies its configuration and reduces its cost of 1577 operation. 1579 Note that use of a Map-Server does not preclude an ETR from also 1580 connecting to the mapping database (i.e., it could also connect to 1581 the LISP-ALT network), but doing so doesn't seem particularly useful, 1582 as the whole purpose of using a Map-Server is to avoid the complexity 1583 of the mapping database protocols. 1585 8.3. Map-Server Processing 1587 Once a Map-Server has EID-Prefixes registered by its client ETRs, it 1588 can accept and process Map-Requests for them. 1590 In response to a Map-Request, the Map-Server first checks to see if 1591 the destination EID matches a configured EID-Prefix. If there is no 1592 match, the Map-Server returns a Negative Map-Reply with action code 1593 "Natively-Forward" and a 15-minute TTL. This can occur if a Map 1594 Request is received for a configured aggregate EID-Prefix for which 1595 no more-specific EID-Prefix exists; it indicates the presence of a 1596 non-LISP "hole" in the aggregate EID-Prefix. 1598 Next, the Map-Server checks to see if any ETRs have registered the 1599 matching EID-Prefix. If none are found, then the Map-Server returns 1600 a Negative Map-Reply with action code "Natively-Forward" and a 1601 1-minute TTL. 1603 If the EID-prefix is either registered or not registered to the 1604 mapping system and there is a policy in the Map-Server to have the 1605 requestor drop packets for the matching EID-prefix, then a Drop/ 1606 Policy-Denied action is returned. If the EID-prefix is registered or 1607 not registered and there is a authentication failure, then a Drop/ 1608 Authentication- failure action is returned. If either of these 1609 actions result as a temporary state in policy or authentication then 1610 a Send-Map-Request action with 1-minute TTL MAY be returned to allow 1611 the requestor to retry the Map-Request. 1613 If any of the registered ETRs for the EID-Prefix have requested proxy 1614 reply service, then the Map-Server answers the request instead of 1615 forwarding it. It returns a Map-Reply with the EID-Prefix, RLOCs, 1616 and other information learned through the registration process. 1618 If none of the ETRs have requested proxy reply service, then the Map- 1619 Server re-encapsulates and forwards the resulting Encapsulated Map- 1620 Request to one of the registered ETRs. It does not otherwise alter 1621 the Map-Request, so any Map-Reply sent by the ETR is returned to the 1622 RLOC in the Map-Request, not to the Map-Server. Unless also acting 1623 as a Map-Resolver, a Map-Server should never receive Map-Replies; any 1624 such messages SHOULD be discarded without response, perhaps 1625 accompanied by the logging of a diagnostic message if the rate of 1626 Map-Replies is suggestive of malicious traffic. 1628 8.4. Map-Resolver Processing 1630 Upon receipt of an Encapsulated Map-Request, a Map-Resolver 1631 decapsulates the enclosed message and then searches for the requested 1632 EID in its local database of mapping entries (statically configured 1633 or learned from associated ETRs if the Map-Resolver is also a Map- 1634 Server offering proxy reply service). If it finds a matching entry, 1635 it returns a LISP Map-Reply with the known mapping. 1637 If the Map-Resolver does not have the mapping entry and if it can 1638 determine that the EID is not in the mapping database (for example, 1639 if LISP-ALT is used, the Map-Resolver will have an ALT forwarding 1640 table that covers the full EID space), it immediately returns a 1641 negative LISP Map-Reply, with action code "Natively-Forward" and a 1642 15-minute TTL. To minimize the number of negative cache entries 1643 needed by an ITR, the Map-Resolver SHOULD return the least-specific 1644 prefix that both matches the original query and does not match any 1645 EID-Prefix known to exist in the LISP-capable infrastructure. 1647 If the Map-Resolver does not have sufficient information to know 1648 whether the EID exists, it needs to forward the Map-Request to 1649 another device that has more information about the EID being 1650 requested. To do this, it forwards the unencapsulated Map-Request, 1651 with the original ITR RLOC as the source, to the mapping database 1652 system. Using LISP-ALT, the Map-Resolver is connected to the ALT 1653 network and sends the Map-Request to the next ALT hop learned from 1654 its ALT BGP neighbors. The Map-Resolver does not send any response 1655 to the ITR; since the source RLOC is that of the ITR, the ETR or Map- 1656 Server that receives the Map-Request over the ALT and responds will 1657 do so directly to the ITR. 1659 8.4.1. Anycast Operation 1661 A Map-Resolver can be set up to use "anycast", where the same address 1662 is assigned to multiple Map-Resolvers and is propagated through IGP 1663 routing, to facilitate the use of a topologically close Map-Resolver 1664 by each ITR. 1666 ETRs MAY have anycast RLOC addresses which are registered as part of 1667 their RLOC-set to the mapping system. However, registrations MUST 1668 use their unique RLOC addresses, distinct authentication keys or 1669 different XTR-IDs to identify security associations with the Map- 1670 Servers. 1672 9. Security Considerations 1674 A LISP threat analysis can be found in [RFC7835]. In what follows we 1675 highlight security considerations that apply when LISP is deployed in 1676 environments such as those specified in Section 1.1, where the 1677 following assumptions hold: 1679 1. The Mapping System is secure and trusted, and for the purpose of 1680 this security considerations the Mapping System is considered as 1681 one trusted element. 1683 2. The ETRs have a pre-configured trust relationship with the 1684 Mapping System, which includes some form of shared secret, and 1685 the Mapping System is aware of which EIDs an ETR can advertise. 1686 How those keys and mappings gets established is out of the scope 1687 of this document. 1689 3. LISP-SEC [I-D.ietf-lisp-sec] MUST be implemented. Network 1690 operators should carefully weight how the LISP-SEC threat model 1691 applies to their particular use case or deployment. If they 1692 decide to ignore a particular recommendation, they should make 1693 sure the risk associated with the corresponding threats is well 1694 understood. 1696 The Map-Request/Map-Reply message exchange can be exploited by an 1697 attacker to mount DoS and/or amplification attacks. Attackers can 1698 send Map-Requests at high rates to overload LISP nodes and increase 1699 the state maintained by such nodes or consume CPU cycles. Such 1700 threats can be mitigated by systematically applying filters and rate 1701 limiters. 1703 The Map-Request/Map-Reply message exchange to inject forged mappings 1704 directly in the ITR EID-to-RLOC map-cache. This can lead to traffic 1705 being redirected to the attacker, see further details in [RFC7835]. 1706 In addition, valid ETRs in the system can perform overclaiming 1707 attacks. In this case, attackers can claim to own an EID-prefix that 1708 is larger than the prefix owned by the ETR. Such attacks can be 1709 addressed by using LISP-SEC [I-D.ietf-lisp-sec]. The LISP-SEC 1710 protocol defines a mechanism for providing origin authentication, 1711 integrity, protection, and prevention of 'man-in-the-middle' and 1712 'prefix overclaiming' attacks on the Map-Request/Map-Reply exchange. 1713 In addition and while beyond the scope of securing an individual Map- 1714 Server or Map-Resolver, it should be noted that LISP-SEC can be 1715 complemented by additional security mechanisms defined by the Mapping 1716 System Infrastructure. For instance, BGP-based LISP-ALT [RFC6836] 1717 can take advantage of standards work on adding security to BGP while 1718 LISP-DDT [RFC8111] defines its own additional security mechanisms. 1720 To publish an authoritative EID-to-RLOC mapping with a Map-Server 1721 using the Map-Register message, an ETR includes authentication data 1722 that is a MAC of the entire message using a key derived from the pre- 1723 shared secret. An implementation MUST support HMAC-SHA256-128+HKDF- 1724 SHA256 [RFC4868]. The Map-Register message includes protection for 1725 replay attacks by a man-in-the-middle. However, a compromised ETR 1726 can overclaim the prefix it owns and successfully register it on its 1727 corresponding Map-Server. To mitigate this and as noted in 1728 Section 8.2, a Map-Server MUST verify that all EID-Prefixes 1729 registered by an ETR match the configuration stored on the Map- 1730 Server. 1732 Deployments concerned about manipulations of Map-Request and Map- 1733 Reply messages, and malicious ETR EID prefix overclaiming MUST drop 1734 LISP Control Plane messages that do not contain LISP-SEC material 1735 (S-bit, EID-AD, OTK-AD, PKT-AD). 1737 Mechanisms to encrypt, support privacy, prevent eavesdropping and 1738 packet tampering for messages exchanged between xTRs, xTRs and the 1739 mapping system, and nodes that make up the mapping system, SHOULD be 1740 deployed. Examples of this are DTLS [RFC6347] or LISP-crypto 1741 [RFC8061]. 1743 10. Privacy Considerations 1745 As noted by [RFC6973] privacy is a complex issue that greatly depends 1746 on the specific protocol use-case and deployment. As noted in 1747 section 1.1 of [I-D.ietf-lisp-rfc6830bis] LISP focuses on use-cases 1748 where entities communicate over the public Internet while keeping 1749 separate addressing and topology. In what follows we detail the 1750 privacy threats introduced by the LISP Control Plane, the analysis is 1751 based on the guidelines detailed in [RFC6973]. 1753 LISP can use long-lived identifiers (EIDs) that survive mobility 1754 events. Such identifiers bind to the RLOCs of the nodes, which 1755 represents the topological location with respect to the specific LISP 1756 deployments. In addition, EID-to-RLOC mappings are typically 1757 considered public information within the LISP deployment when 1758 control-plane messages are not encrypted, and can be eavesdropped 1759 while Map-Request messages are sent to the corresponding Map- 1760 Resolvers or Map-Register messages to Map-Servers. 1762 In this context, attackers can correlate the EID with the RLOC and 1763 track the corresponding user topological location and/or mobility. 1764 This can be achieved by off-path attackers, if they are 1765 authenticated, by querying the mapping system. Deployments concerned 1766 about this threat can use access control-lists or stronger 1767 authentication mechanisms [I-D.ietf-lisp-ecdsa-auth] in the mapping 1768 system to make sure that only authorized users can access this 1769 information (data minimization). Use of ephemeral EIDs 1770 [I-D.ietf-lisp-eid-anonymity] to achieve anonymity is another 1771 mechanism to lessen persistency and identity tracking. 1773 11. Changes since RFC 6833 1775 For implementation considerations, the following major changes have 1776 been made to this document since RFC 6833 was published: 1778 o A Map-Notify-Ack message is added in this document to provide 1779 reliability for Map-Notify messages. Any receiver of a Map-Notify 1780 message must respond with a Map-Notify-Ack message. Map-Servers 1781 who are senders of Map-Notify messages, must queue the Map-Notify 1782 contents until they receive a Map-Notify-Ack with the nonce used 1783 in the Map-Notify message. Note that implementations for Map- 1784 Notify-Ack support already exist and predate this document. 1786 o This document is incorporating the codepoint for the Map-Referral 1787 message from the LISP-DDT specification [RFC8111] to indicate that 1788 a Map-Server must send the final Map-Referral message when it 1789 participates in the LISP-DDT mapping system procedures. 1791 o The L" and "D" bits are added to the Map-Request message. See 1792 Section 5.3 for details. 1794 o The "S", "I", "E", "T", "a", "R", and "M" bits are added to the 1795 Map-Register message. See Section 5.6 for details. 1797 o The 16-bit Key-ID field of the Map-Register message has been split 1798 into a 8-bit Key-ID field and a 8-bit Algorithm-ID field. 1800 o The nonce and the authentication data in the Map-Register message 1801 have a different behaviour, see Section 5.6 for details. 1803 o This document adds two new Action values that are in an EID-record 1804 that appear in Map-Reply, Map-Register, Map-Notify, and Map- 1805 Notify-Ack messages. The Drop/Policy-Denied and Drop/Auth-Failure 1806 are the descriptions for the two new action values. See 1807 Section 5.4 for details. 1809 12. IANA Considerations 1811 This section provides guidance to the Internet Assigned Numbers 1812 Authority (IANA) regarding registration of values related to this 1813 LISP Control-Plane specification, in accordance with BCP 26 1814 [RFC8126]. 1816 There are three namespaces (listed in the sub-sections below) in LISP 1817 that have been registered. 1819 o LISP IANA registry allocations should not be made for purposes 1820 unrelated to LISP routing or transport protocols. 1822 o The following policies are used here with the meanings defined in 1823 BCP 26: "Specification Required", "IETF Review", "Experimental 1824 Use", and "First Come First Served". 1826 12.1. LISP UDP Port Numbers 1828 The IANA registry has allocated UDP port number 4342 for the LISP 1829 Control-Plane. IANA has updated the description for UDP port 4342 as 1830 follows: 1832 Keyword Port Transport Layer Description 1833 ------- ---- --------------- ----------- 1834 lisp-control 4342 udp LISP Control Packets 1836 12.2. LISP Packet Type Codes 1838 It is being requested that the IANA be authoritative for LISP Packet 1839 Type definitions and it is requested to replace the [RFC6830] 1840 registry message references with the RFC number assigned to this 1841 document. 1843 Based on deployment experience of [RFC6830], the Map-Notify-Ack 1844 message, message type 5, was added by this document. This document 1845 requests IANA to add it to the LISP Packet Type Registry. 1847 Name Number Defined in 1848 ---- ------ ----------- 1849 LISP Map-Notify-Ack 5 RFC6833bis 1851 12.3. LISP Map-Reply EID-Record Action Codes 1853 New ACT values can be allocated through IETF review or IESG approval. 1854 Four values have already been allocated by [RFC6830], IANA is 1855 requested to replace the [RFC6830] reference for this registry with 1856 the RFC number assigned to this document and the [RFC6830]. Action 1857 values references with the RFC number assigned to this document. 1858 This specification changes the name of ACT type 3 value from "Drop" 1859 to "Drop/No-Reason" as well as adding two new ACT values, the "Drop/ 1860 Policy-Denied" (type 4) and "Drop/Authentication-Failure" (type 5). 1862 +-------+--------------------+-------------------------+------------+ 1863 | Value | Action | Description | Raeference | 1864 +-------+--------------------+-------------------------+------------+ 1865 | 4 | Drop/Policy-Denied | A packet matching this | RFC6833bis | 1866 | | | Map-Cache entry is | | 1867 | | | dropped because | | 1868 | | | the target EWID is | | 1869 | | | policy-denied by the | | 1870 | | | xTR or the mapping | | 1871 | | | system. | | 1872 | 5 | Drop/Auth-Failure | Packet matching the | RFC6833bis | 1873 | | | Map-Cache entry is | | 1874 | | | dropped beacuse the | | 1875 | | | Map-Request for the | | 1876 | | | target EID fails an | | 1877 | | | authentication check | | 1878 | | | by the xTR or the | | 1879 | | | mapping system. | | 1880 +-------+--------------------+-------------------------+------------+ 1882 LISP Map-Reply Action Values 1884 In addition, LISP has a number of flag fields and reserved fields, 1885 such as the LISP header flags field [I-D.ietf-lisp-rfc6830bis]. New 1886 bits for flags in these fields can be implemented after IETF review 1887 or IESG approval, but these need not be managed by IANA. 1889 12.4. LISP Address Type Codes 1891 LISP Canonical Address Format (LCAF) [RFC8060] is an 8-bit field that 1892 defines LISP-specific encodings for AFI value 16387. LCAF encodings 1893 are used for specific use-cases where different address types for 1894 EID-records and RLOC-records are required. 1896 The IANA registry "LISP Canonical Address Format (LCAF) Types" is 1897 used for LCAF types. The registry for LCAF types use the 1898 Specification Required policy [RFC8126]. Initial values for the 1899 registry as well as further information can be found in [RFC8060]. 1901 Therefore, there is no longer a need for the "LISP Address Type 1902 Codes" registry requested by [RFC6830]. This document requests to 1903 remove it. 1905 12.5. LISP Algorithm ID Numbers 1907 In [RFC6830], a request for a "LISP Key ID Numbers" registry was 1908 submitted. This document renames the registry to "LISP Algorithm ID 1909 Numbers" and requests the IANA to make the name change. 1911 The following Algorithm ID values are defined by this specification 1912 as used in any packet type that references a 'Algorithm ID' field: 1914 Name Number MAC KDF 1915 ------------------------------------------------------- 1916 None 0 None None 1917 HMAC-SHA-1-96-None 1 [RFC2404] None 1918 HMAC-SHA-256-128-None 2 [RFC4868] None 1919 HMAC-SHA256-128+HKDF-SHA2562 3 [RFC4868] [RFC4868] 1921 Number values are in the range of 0 to 255. The allocation of values 1922 is on a first come first served basis. 1924 12.6. LISP Bit Flags 1926 This document asks IANA to create a registry for allocation of bits 1927 in several headers of the LISP control plane, namely in the Map- 1928 Request, Map-Reply, Map-Register, Encapsulated Control Message (ECM) 1929 messages. Bit allocations are also requested for EID-records and 1930 RLOC-records. The registry created should be named "LISP Control 1931 Plane Header Bits". A sub-registry needs to be created per each 1932 message and EID-record. The name of each sub-registry is indicated 1933 below, along with its format and allocation of bits defined in this 1934 document. Any additional bits allocation, requires a specification, 1935 according with [RFC8126] policies. 1937 Sub-Registry: Map-Request Header Bits [Section 5.2]: 1939 0 1 2 3 1940 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 1941 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1942 |Type=1 |A|M|P|S|p|s|R|R| Rsvd |L|D| IRC | Record Count | 1943 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1944 +---------+---------------+-----------+-----------------------------+ 1945 | Spec | IANA Name | Bit | Description | 1946 | Name | | Position | | 1947 +---------+---------------+-----------+-----------------------------+ 1948 | A | map-request-A | 4 | Authoritative Bit | 1949 | M | map-request-M | 5 | Map Data Present Bit | 1950 | P | map-request-P | 6 | RLOC-Probe Request Bit | 1951 | S | map-request-S | 7 | Solicit Map-Request (SMR) | 1952 | | | | Bit | 1953 | p | map-request-p | 8 | Proxy-ITR Bit | 1954 | s | map-request-s | 9 | Solicit Map-Request Invoked | 1955 | | | | Bit | 1956 | L | map-request-L | 17 | Local xTR Bit | 1957 | D | map-request-D | 18 | Don't Map-Reply Bit | 1958 +---------+---------------+-----------+-----------------------------+ 1960 LISP Map-Request Header Bits 1962 Sub-Registry: Map-Reply Header Bits [Section 5.4]: 1964 0 1 2 3 1965 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 1966 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1967 |Type=2 |P|E|S| Reserved | Record Count | 1968 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1970 +-----------+-------------+--------------+------------------------+ 1971 | Spec Name | IANA Name | Bit Position | Description | 1972 +-----------+-------------+--------------+------------------------+ 1973 | P | map-reply-P | 4 | RLOC-Probe Bit | 1974 | E | map-reply-E | 5 | Echo Nonce Capable Bit | 1975 | S | map-reply-S | 6 | Security Bit | 1976 +-----------+-------------+--------------+------------------------+ 1978 LISP Map-Reply Header Bits 1980 Sub-Registry: Map-Register Header Bits [Section 5.6]: 1982 0 1 2 3 1983 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 1984 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1985 |Type=3 |P|S|I| Reserved |E|T|a|R|M| Record Count | 1986 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1987 +-----------+----------------+--------------+----------------------+ 1988 | Spec Name | IANA Name | Bit Position | Description | 1989 +-----------+----------------+--------------+----------------------+ 1990 | P | map-register-P | 4 | Proxy Map-Reply Bit | 1991 | S | map-register-S | 5 | LISP-SEC Capable Bit | 1992 | I | map-register-I | 6 | xTR-ID present flag | 1993 +-----------+----------------+--------------+----------------------+ 1995 LISP Map-Register Header Bits 1997 Sub-Registry: Encapsulated Control Message (ECM) Header Bits 1998 [Section 5.8]: 2000 0 1 2 3 2001 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 2002 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2003 |Type=8 |S|D|E|M| Reserved | 2004 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2006 +-----------+-----------+--------------+----------------------------+ 2007 | Spec Name | IANA Name | Bit Position | Description | 2008 +-----------+-----------+--------------+----------------------------+ 2009 | S | ecm-S | 4 | Security Bit | 2010 | D | ecm-D | 5 | LISP-DDT Bit | 2011 | E | ecm-E | 6 | Forward to ETR Bit | 2012 | M | ecm-M | 7 | Destined to Map-Server Bit | 2013 +-----------+-----------+--------------+----------------------------+ 2015 LISP Encapsulated Control Message (ECM) Header Bits 2017 Sub-Registry: EID-Record Header Bits [Section 5.4]: 2019 0 1 2 3 2020 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 2021 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2022 | Locator Count | EID mask-len | ACT |A| Reserved | 2023 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2025 +-----------+--------------+--------------+-------------------+ 2026 | Spec Name | IANA Name | Bit Position | Description | 2027 +-----------+--------------+--------------+-------------------+ 2028 | A | eid-record-A | 19 | Authoritative Bit | 2029 +-----------+--------------+--------------+-------------------+ 2031 LISP EID-Record Header Bits 2033 Sub-Registry: RLOC-Record Header Bits [Section 5.4]: 2035 0 1 2 3 2036 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 2037 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2038 | Unused Flags |L|p|R| Loc-AFI | 2039 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 2041 +-----------+---------------+--------------+----------------------+ 2042 | Spec Name | IANA Name | Bit Position | Description | 2043 +-----------+---------------+--------------+----------------------+ 2044 | L | rloc-record-L | 13 | Local RLOC Bit | 2045 | p | rloc-record-p | 19 | RLOC-Probe Reply Bit | 2046 | R | rloc-record-R | 19 | RLOC Reachable Bit | 2047 +-----------+---------------+--------------+----------------------+ 2049 LISP RLOC-Record Header Bits 2051 13. References 2053 13.1. Normative References 2055 [I-D.ietf-lisp-6834bis] 2056 Iannone, L., Saucez, D., and O. Bonaventure, "Locator/ID 2057 Separation Protocol (LISP) Map-Versioning", draft-ietf- 2058 lisp-6834bis-06 (work in progress), February 2020. 2060 [I-D.ietf-lisp-rfc6830bis] 2061 Farinacci, D., Fuller, V., Meyer, D., Lewis, D., and A. 2062 Cabellos-Aparicio, "The Locator/ID Separation Protocol 2063 (LISP)", draft-ietf-lisp-rfc6830bis-32 (work in progress), 2064 March 2020. 2066 [I-D.ietf-lisp-rfc8113bis] 2067 Boucadair, M. and C. Jacquenet, "Locator/ID Separation 2068 Protocol (LISP): Shared Extension Message & IANA Registry 2069 for Packet Type Allocations", draft-ietf-lisp- 2070 rfc8113bis-03 (work in progress), January 2019. 2072 [I-D.ietf-lisp-sec] 2073 Maino, F., Ermagan, V., Cabellos-Aparicio, A., and D. 2074 Saucez, "LISP-Security (LISP-SEC)", draft-ietf-lisp-sec-21 2075 (work in progress), July 2020. 2077 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 2078 Requirement Levels", BCP 14, RFC 2119, 2079 DOI 10.17487/RFC2119, March 1997, 2080 . 2082 [RFC2404] Madson, C. and R. Glenn, "The Use of HMAC-SHA-1-96 within 2083 ESP and AH", RFC 2404, DOI 10.17487/RFC2404, November 2084 1998, . 2086 [RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, 2087 "Randomness Requirements for Security", BCP 106, RFC 4086, 2088 DOI 10.17487/RFC4086, June 2005, 2089 . 2091 [RFC4868] Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-SHA- 2092 384, and HMAC-SHA-512 with IPsec", RFC 4868, 2093 DOI 10.17487/RFC4868, May 2007, 2094 . 2096 [RFC6347] Rescorla, E. and N. Modadugu, "Datagram Transport Layer 2097 Security Version 1.2", RFC 6347, DOI 10.17487/RFC6347, 2098 January 2012, . 2100 [RFC8085] Eggert, L., Fairhurst, G., and G. Shepherd, "UDP Usage 2101 Guidelines", BCP 145, RFC 8085, DOI 10.17487/RFC8085, 2102 March 2017, . 2104 [RFC8126] Cotton, M., Leiba, B., and T. Narten, "Guidelines for 2105 Writing an IANA Considerations Section in RFCs", BCP 26, 2106 RFC 8126, DOI 10.17487/RFC8126, June 2017, 2107 . 2109 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 2110 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 2111 May 2017, . 2113 13.2. Informative References 2115 [AFI] "Address Family Identifier (AFIs)", ADDRESS FAMILY 2116 NUMBERS http://www.iana.org/assignments/address-family- 2117 numbers/address-family-numbers.xhtml?, Febuary 2007. 2119 [GTP-3GPP] 2120 "General Packet Radio System (GPRS) Tunnelling Protocol 2121 User Plane (GTPv1-U)", TS.29.281 2122 https://portal.3gpp.org/desktopmodules/Specifications/ 2123 SpecificationDetails.aspx?specificationId=1699, January 2124 2015. 2126 [I-D.herbert-intarea-ila] 2127 Herbert, T. and P. Lapukhov, "Identifier-locator 2128 addressing for IPv6", draft-herbert-intarea-ila-01 (work 2129 in progress), March 2018. 2131 [I-D.ietf-lisp-ecdsa-auth] 2132 Farinacci, D. and E. Nordmark, "LISP Control-Plane ECDSA 2133 Authentication and Authorization", draft-ietf-lisp-ecdsa- 2134 auth-03 (work in progress), March 2020. 2136 [I-D.ietf-lisp-eid-anonymity] 2137 Farinacci, D., Pillay-Esnault, P., and W. Haddad, "LISP 2138 EID Anonymity", draft-ietf-lisp-eid-anonymity-08 (work in 2139 progress), April 2020. 2141 [I-D.ietf-lisp-eid-mobility] 2142 Portoles-Comeras, M., Ashtaputre, V., Moreno, V., Maino, 2143 F., and D. Farinacci, "LISP L2/L3 EID Mobility Using a 2144 Unified Control Plane", draft-ietf-lisp-eid-mobility-06 2145 (work in progress), May 2020. 2147 [I-D.ietf-lisp-gpe] 2148 Maino, F., Lemon, J., Agarwal, P., Lewis, D., and M. 2149 Smith, "LISP Generic Protocol Extension", draft-ietf-lisp- 2150 gpe-19 (work in progress), July 2020. 2152 [I-D.ietf-lisp-introduction] 2153 Cabellos-Aparicio, A. and D. Saucez, "An Architectural 2154 Introduction to the Locator/ID Separation Protocol 2155 (LISP)", draft-ietf-lisp-introduction-13 (work in 2156 progress), April 2015. 2158 [I-D.ietf-lisp-mn] 2159 Farinacci, D., Lewis, D., Meyer, D., and C. White, "LISP 2160 Mobile Node", draft-ietf-lisp-mn-07 (work in progress), 2161 March 2020. 2163 [I-D.ietf-lisp-pubsub] 2164 Rodriguez-Natal, A., Ermagan, V., Cabellos-Aparicio, A., 2165 Barkai, S., and M. Boucadair, "Publish/Subscribe 2166 Functionality for LISP", draft-ietf-lisp-pubsub-06 (work 2167 in progress), July 2020. 2169 [I-D.ietf-nvo3-vxlan-gpe] 2170 Maino, F., Kreeger, L., and U. Elzur, "Generic Protocol 2171 Extension for VXLAN (VXLAN-GPE)", draft-ietf-nvo3-vxlan- 2172 gpe-10 (work in progress), July 2020. 2174 [I-D.ietf-opsec-icmp-filtering] 2175 Gont, F., Gont, G., and C. Pignataro, "Recommendations for 2176 filtering ICMP messages", draft-ietf-opsec-icmp- 2177 filtering-04 (work in progress), July 2013. 2179 [RFC1035] Mockapetris, P., "Domain names - implementation and 2180 specification", STD 13, RFC 1035, DOI 10.17487/RFC1035, 2181 November 1987, . 2183 [RFC1071] Braden, R., Borman, D., and C. Partridge, "Computing the 2184 Internet checksum", RFC 1071, DOI 10.17487/RFC1071, 2185 September 1988, . 2187 [RFC2104] Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed- 2188 Hashing for Message Authentication", RFC 2104, 2189 DOI 10.17487/RFC2104, February 1997, 2190 . 2192 [RFC2890] Dommety, G., "Key and Sequence Number Extensions to GRE", 2193 RFC 2890, DOI 10.17487/RFC2890, September 2000, 2194 . 2196 [RFC4984] Meyer, D., Ed., Zhang, L., Ed., and K. Fall, Ed., "Report 2197 from the IAB Workshop on Routing and Addressing", 2198 RFC 4984, DOI 10.17487/RFC4984, September 2007, 2199 . 2201 [RFC6234] Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms 2202 (SHA and SHA-based HMAC and HKDF)", RFC 6234, 2203 DOI 10.17487/RFC6234, May 2011, 2204 . 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-26 2301 o Posted November 2019. 2303 o Fixed the required (MUST implement) authentcation algorithms. 2305 o Fixed a large set of minor comments and edits. 2307 B.2. Changes to draft-ietf-lisp-rfc6833bis-25 2309 o Posted June 2019. 2311 o Added change requested by Mirja describing Record Count in an EID- 2312 record. 2314 o Fixed Requirements Notation section per Pete. 2316 o Added KDF for shared-secret 2318 o Specified several rate-limiters for control messages 2320 B.3. Changes to draft-ietf-lisp-rfc6833bis-24 2322 o Posted February 2019. 2324 o Added suggested text from Albert that Benjamin Kaduk agreed with. 2326 o Added suggested editorial comments from Alvaro's rewview. 2328 o Ran document through IDnits. Fixed bugs found. 2330 B.4. Changes to draft-ietf-lisp-rfc6833bis-23 2332 o Posted December 2018. 2334 o Added to Security Considerations section that deployments that 2335 care about prefix over claiming should use LISP-SEC. 2337 o Added to Security Considerations section that DTLS or LISP-crypto 2338 be used for control-plane privacy. 2340 o Make LISP-SEC a normative reference. 2342 o Make it more clear where field descriptions are spec'ed when 2343 referencing to the same fields in other packet types. 2345 B.5. Changes to draft-ietf-lisp-rfc6833bis-22 2347 o Posted week after IETF November 2018. 2349 o No longer need to use IPSEC for replay attacks. 2351 B.6. Changes to draft-ietf-lisp-rfc6833bis-21 2353 o Posted early November 2018. 2355 o Added I-bit back in because its necessary to use for Map-Register 2356 replay attack scenarios. The Map-Server tracks the nonce per xTR- 2357 ID to detect duplicate or replayed Map-Register messages. 2359 B.7. Changes to draft-ietf-lisp-rfc6833bis-20 2361 o Posted late October 2018. 2363 o Changed description about "reserved" bits to state "reserved and 2364 unassigned". 2366 o Make it more clear how Map-Register nonce processing is performed 2367 in an ETR and Map-Server. 2369 B.8. Changes to draft-ietf-lisp-rfc6833bis-19 2371 o Posted mid October 2018. 2373 o Added Fabio text to the Security Considerations section. 2375 B.9. Changes to draft-ietf-lisp-rfc6833bis-18 2377 o Posted mid October 2018. 2379 o Fixed comments from Eric after more email clarity. 2381 B.10. Changes to draft-ietf-lisp-rfc6833bis-17 2383 o Posted early October 2018. 2385 o Changes to reflect comments from Sep 27th Telechat. 2387 o Added all flag bit definitions as request for allocation in IANA 2388 Considersations section. 2390 o Added an applicability statement in section 1 to address security 2391 concerns from Telechat. 2393 o Moved m-bit description and IANA request to draft-ietf-lisp-mn. 2395 o Moved I-bit description and IANA request to draft-ietf-lisp- 2396 pubsub. 2398 B.11. Changes to draft-ietf-lisp-rfc6833bis-16 2400 o Posted Late-September 2018. 2402 o Re-wrote Security Considerations section. Thanks Albert. 2404 o Added Alvaro text to be more clear about IANA actions. 2406 B.12. Changes to draft-ietf-lisp-rfc6833bis-15 2408 o Posted mid-September 2018. 2410 o Changes to reflect comments from Colin and Mirja. 2412 B.13. Changes to draft-ietf-lisp-rfc6833bis-14 2414 o Posted September 2018. 2416 o Changes to reflect comments from Genart, RTGarea, and Secdir 2417 reviews. 2419 B.14. Changes to draft-ietf-lisp-rfc6833bis-13 2421 o Posted August 2018. 2423 o Final editorial changes before RFC submission for Proposed 2424 Standard. 2426 o Added section "Changes since RFC 6833" so implementators are 2427 informed of any changes since the last RFC publication. 2429 B.15. Changes to draft-ietf-lisp-rfc6833bis-12 2431 o Posted late July 2018. 2433 o Moved RFC6830bis and RFC6834bis to Normative References. 2435 B.16. Changes to draft-ietf-lisp-rfc6833bis-11 2437 o Posted July 2018. 2439 o Fixed Luigi editorial comments to ready draft for RFC status and 2440 ran through IDNITs again. 2442 B.17. Changes to draft-ietf-lisp-rfc6833bis-10 2444 o Posted after LISP WG at IETF week March. 2446 o Move AD field encoding after S-bit in the ECM packet format 2447 description section. 2449 o Say more about when the new Drop actions should be sent. 2451 B.18. Changes to draft-ietf-lisp-rfc6833bis-09 2453 o Posted March IETF week 2018. 2455 o Fixed editorial comments submitted by document shepherd Luigi 2456 Iannone. 2458 B.19. Changes to draft-ietf-lisp-rfc6833bis-08 2460 o Posted March 2018. 2462 o Added RLOC-probing algorithm. 2464 o Added Solicit-Map Request algorithm. 2466 o Added several mechanisms (from 6830bis) regarding Routing Locator 2467 Reachability. 2469 o Added port 4342 to IANA Considerations section. 2471 B.20. Changes to draft-ietf-lisp-rfc6833bis-07 2473 o Posted December 2017. 2475 o Make it more clear in a couple of places that RLOCs are used to 2476 locate ETRs more so than for Map-Server Map-Request forwarding. 2478 o Make it clear that "encapsualted" for a control message is an ECM 2479 based message. 2481 o Make it more clear what messages use source-port 4342 and which 2482 ones use destinatino-port 4342. 2484 o Don't make DDT references when the mapping transport system can be 2485 of any type and the referneced text is general to it. 2487 o Generalize text when referring to the format of an EID-prefix. 2488 Can use othe AFIs then IPv4 and IPv6. 2490 o Many editorial changes to clarify text. 2492 o Changed some "must", "should", and "may" to capitalized. 2494 o Added definitions for Map-Request and Map-Reply messages. 2496 o Ran document through IDNITs. 2498 B.21. Changes to draft-ietf-lisp-rfc6833bis-06 2500 o Posted October 2017. 2502 o Spec the I-bit to include the xTR-ID in a Map-Request message to 2503 be consistent with the Map-Register message and to anticipate the 2504 introduction of pubsub functionality to allow Map-Requests to 2505 subscribe to RLOC-set changes. 2507 o Updated references for individual submissions that became working 2508 group documents. 2510 o Updated references for working group documents that became RFCs. 2512 B.22. Changes to draft-ietf-lisp-rfc6833bis-05 2514 o Posted May 2017. 2516 o Update IANA Considerations section based on new requests from this 2517 document and changes from what was requested in [RFC6830]. 2519 B.23. Changes to draft-ietf-lisp-rfc6833bis-04 2521 o Posted May 2017. 2523 o Clarify how the Key-ID field is used in Map-Register and Map- 2524 Notify messages. Break the 16-bit field into a 8-bit Key-ID field 2525 and a 8-bit Algorithm-ID field. 2527 o Move the Control-Plane codepoints from the IANA Considerations 2528 section of RFC6830bis to the IANA Considerations section of this 2529 document. 2531 o In the "LISP Control Packet Type Allocations" section, indicate 2532 how message Types are IANA allocated and how experimental RFC8113 2533 sub-types should be requested. 2535 B.24. Changes to draft-ietf-lisp-rfc6833bis-03 2537 o Posted April 2017. 2539 o Add types 9-14 and specify they are not assigned. 2541 o Add the "LISP Shared Extension Message" type and point to RFC8113. 2543 B.25. Changes to draft-ietf-lisp-rfc6833bis-02 2545 o Posted April 2017. 2547 o Clarify that the LISP Control-Plane document defines how the LISP 2548 Data-Plane uses Map-Requests with either the SMR-bit set or the 2549 P-bit set supporting mapping updates and RLOC-probing. Indicating 2550 that other Data-Planes can use the same mechanisms or their own 2551 defined mechanisms to achieve the same functionality. 2553 B.26. Changes to draft-ietf-lisp-rfc6833bis-01 2555 o Posted March 2017. 2557 o Include references to new RFCs published. 2559 o Remove references to self. 2561 o Change references from RFC6830 to RFC6830bis. 2563 o Add two new action/reasons to a Map-Reply has posted to the LISP 2564 WG mailing list. 2566 o In intro section, add refernece to I-D.ietf-lisp-introduction. 2568 o Removed Open Issues section and references to "experimental". 2570 B.27. Changes to draft-ietf-lisp-rfc6833bis-00 2572 o Posted December 2016. 2574 o Created working group document from draft-farinacci-lisp 2575 -rfc6833-00 individual submission. No other changes made. 2577 B.28. Changes to draft-farinacci-lisp-rfc6833bis-00 2579 o Posted November 2016. 2581 o This is the initial draft to turn RFC 6833 into RFC 6833bis. 2583 o The document name has changed from the "Locator/ID Separation 2584 Protocol (LISP) Map-Server Interface" to the "Locator/ID 2585 Separation Protocol (LISP) Control-Plane". 2587 o The fundamental change was to move the Control-Plane messages from 2588 RFC 6830 to this document in an effort so any IETF developed or 2589 industry created Data-Plane could use the LISP mapping system and 2590 Control-Plane. 2592 o Update Control-Plane messages to incorporate what has been 2593 implemented in products during the early phase of LISP development 2594 but wasn't able to make it into RFC6830 and RFC6833 to make the 2595 Experimental RFC deadline. 2597 o Indicate there may be nodes in the mapping system that are not MRs 2598 or MSs, that is a ALT-node or a DDT-node. 2600 o Include LISP-DDT in Map-Resolver section and explain how they 2601 maintain a referral-cache. 2603 o Removed open issue about additional state in Map-Servers. With 2604 [RFC8111], Map-Servers have the same registration state and can 2605 give Map-Resolvers complete information in ms-ack Map-Referral 2606 messages. 2608 o Make reference to the LISP Threats Analysis RFC [RFC7835]. 2610 Authors' Addresses 2612 Dino Farinacci 2613 lispers.net 2615 EMail: farinacci@gmail.com 2617 Fabio Maino 2618 Cisco Systems 2620 EMail: fmaino@cisco.com 2622 Vince Fuller 2623 vaf.net Internet Consulting 2625 EMail: vaf@vaf.net 2627 Albert Cabellos 2628 UPC/BarcelonaTech 2629 Campus Nord, C. Jordi Girona 1-3 2630 Barcelona, Catalunya 2631 Spain 2633 EMail: acabello@ac.upc.edu