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If these are generic example addresses, they should be changed to use any of the ranges defined in RFC 6890 (or successor): 192.0.2.x, 198.51.100.x or 203.0.113.x. ** The document seems to lack a both a reference to RFC 2119 and the recommended RFC 2119 boilerplate, even if it appears to use RFC 2119 keywords. RFC 2119 keyword, line 302: '... Implementations MUST be prepared to a...' RFC 2119 keyword, line 311: '...ol messages. It MUST be checked on re...' RFC 2119 keyword, line 312: '... fails, the packet MUST be dropped....' RFC 2119 keyword, line 378: '...ch indicates that a Map-Request SHOULD...' RFC 2119 keyword, line 379: '...achability probe. The receiver SHOULD...' (44 more instances...) Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (March 28, 2017) is 2584 days in the past. Is this intentional? 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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group V. Fuller 3 Internet-Draft D. Farinacci 4 Intended status: Standards Track Cisco Systems 5 Expires: September 29, 2017 A. Cabellos (Ed.) 6 UPC/BarcelonaTech 7 March 28, 2017 9 Locator/ID Separation Protocol (LISP) Control-Plane 10 draft-ietf-lisp-rfc6833bis-01 12 Abstract 14 This document describes the Control-Plane and Mapping Service for the 15 Locator/ID Separation Protocol (LISP), implemented by two new types 16 of LISP-speaking devices -- the LISP Map-Resolver and LISP Map-Server 17 -- that provides a simplified "front end" for one or more Endpoint ID 18 to Routing Locator mapping databases. 20 By using this control-plane service interface and communicating with 21 Map-Resolvers and Map-Servers, LISP Ingress Tunnel Routers (ITRs) and 22 Egress Tunnel Routers (ETRs) are not dependent on the details of 23 mapping database systems, which facilitates modularity with different 24 database designs. Since these devices implement the "edge" of the 25 LISP infrastructure, connect directly to LISP-capable Internet end 26 sites, and comprise the bulk of LISP-speaking devices, reducing their 27 implementation and operational complexity should also reduce the 28 overall cost and effort of deploying LISP. 30 Status of This Memo 32 This Internet-Draft is submitted in full conformance with the 33 provisions of BCP 78 and BCP 79. 35 Internet-Drafts are working documents of the Internet Engineering 36 Task Force (IETF). Note that other groups may also distribute 37 working documents as Internet-Drafts. The list of current Internet- 38 Drafts is at http://datatracker.ietf.org/drafts/current/. 40 Internet-Drafts are draft documents valid for a maximum of six months 41 and may be updated, replaced, or obsoleted by other documents at any 42 time. It is inappropriate to use Internet-Drafts as reference 43 material or to cite them other than as "work in progress." 45 This Internet-Draft will expire on September 29, 2017. 47 Copyright Notice 49 Copyright (c) 2017 IETF Trust and the persons identified as the 50 document authors. All rights reserved. 52 This document is subject to BCP 78 and the IETF Trust's Legal 53 Provisions Relating to IETF Documents 54 (http://trustee.ietf.org/license-info) in effect on the date of 55 publication of this document. Please review these documents 56 carefully, as they describe your rights and restrictions with respect 57 to this document. Code Components extracted from this document must 58 include Simplified BSD License text as described in Section 4.e of 59 the Trust Legal Provisions and are provided without warranty as 60 described in the Simplified BSD License. 62 Table of Contents 64 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 65 2. Definition of Terms . . . . . . . . . . . . . . . . . . . . . 4 66 3. Basic Overview . . . . . . . . . . . . . . . . . . . . . . . 5 67 4. LISP IPv4 and IPv6 Control-Plane Packet Formats . . . . . . . 7 68 4.1. LISP Control Packet Type Allocations . . . . . . . . . . 9 69 4.2. Map-Request Message Format . . . . . . . . . . . . . . . 10 70 4.3. EID-to-RLOC UDP Map-Request Message . . . . . . . . . . . 12 71 4.4. Map-Reply Message Format . . . . . . . . . . . . . . . . 14 72 4.5. EID-to-RLOC UDP Map-Reply Message . . . . . . . . . . . . 18 73 4.6. Map-Register Message Format . . . . . . . . . . . . . . . 21 74 4.7. Map-Notify/Map-Notify-Ack Message Format . . . . . . . . 24 75 4.8. Encapsulated Control Message Format . . . . . . . . . . . 25 76 5. Interactions with Other LISP Components . . . . . . . . . . . 27 77 5.1. ITR EID-to-RLOC Mapping Resolution . . . . . . . . . . . 27 78 5.2. EID-Prefix Configuration and ETR Registration . . . . . . 28 79 5.3. Map-Server Processing . . . . . . . . . . . . . . . . . . 30 80 5.4. Map-Resolver Processing . . . . . . . . . . . . . . . . . 30 81 5.4.1. Anycast Map-Resolver Operation . . . . . . . . . . . 31 82 6. Security Considerations . . . . . . . . . . . . . . . . . . . 31 83 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 32 84 7.1. Normative References . . . . . . . . . . . . . . . . . . 32 85 7.2. Informative References . . . . . . . . . . . . . . . . . 33 86 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 36 87 Appendix B. Document Change Log . . . . . . . . . . . . . . . . 36 88 B.1. Changes to draft-ietf-lisp-rfc6833bis-01 . . . . . . . . 36 89 B.2. Changes to draft-ietf-lisp-rfc6833bis-00 . . . . . . . . 36 90 B.3. Changes to draft-farinacci-lisp-rfc6833bis-00 . . . . . . 36 91 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 37 93 1. Introduction 95 The Locator/ID Separation Protocol [I-D.ietf-lisp-introduction] and 96 [I-D.ietf-lisp-rfc6830bis] specifies an architecture and mechanism 97 for replacing the addresses currently used by IP with two separate 98 name spaces: Endpoint IDs (EIDs), used within sites; and Routing 99 Locators (RLOCs), used on the transit networks that make up the 100 Internet infrastructure. To achieve this separation, LISP defines 101 protocol mechanisms for mapping from EIDs to RLOCs. In addition, 102 LISP assumes the existence of a database to store and propagate those 103 mappings globally. Several such databases have been proposed; among 104 them are the Content distribution Overlay Network Service for LISP 105 (LISP-CONS) [LISP-CONS], LISP-NERD (a Not-so-novel EID-to-RLOC 106 Database) [RFC6837], LISP Alternative Logical Topology (LISP+ALT) 107 [RFC6836], and LISP Delegated Database Tree (LISP-DDT) 108 [I-D.ietf-lisp-ddt]. 110 The LISP Mapping Service defines two new types of LISP-speaking 111 devices: the Map-Resolver, which accepts Map-Requests from an Ingress 112 Tunnel Router (ITR) and "resolves" the EID-to-RLOC mapping using a 113 mapping database; and the Map-Server, which learns authoritative EID- 114 to-RLOC mappings from an Egress Tunnel Router (ETR) and publishes 115 them in a database. 117 This LISP Control-Plane Mapping Service can be used by many different 118 encapsulation-based or translation-based data-planes which include 119 but are not limited to the ones defined in LISP RFC 6830bis 120 [I-D.ietf-lisp-rfc6830bis], LISP-GPE [I-D.lewis-lisp-gpe], VXLAN 121 [RFC7348], and VXLAN-GPE [I-D.quinn-vxlan-gpe]. 123 Conceptually, LISP Map-Servers share some of the same basic 124 configuration and maintenance properties as Domain Name System (DNS) 125 [RFC1035] servers; likewise, Map-Resolvers are conceptually similar 126 to DNS caching resolvers. With this in mind, this specification 127 borrows familiar terminology (resolver and server) from the DNS 128 specifications. 130 Note that while this document assumes a LISP+ALT database mapping 131 infrastructure to illustrate certain aspects of Map-Server and Map- 132 Resolver operation, the Mapping Service interface can (and likely 133 will) be used by ITRs and ETRs to access other mapping database 134 systems as the LISP infrastructure evolves. 136 The LISP Mapping Service is an important component of the LISP 137 toolset. Issues and concerns about the deployment of LISP for 138 Internet traffic are discussed in [I-D.ietf-lisp-rfc6830bis]. 140 2. Definition of Terms 142 Map-Server: A network infrastructure component that learns of EID- 143 Prefix mapping entries from an ETR, via the registration mechanism 144 described below, or some other authoritative source if one exists. 145 A Map-Server publishes these EID-Prefixes in a mapping database. 147 Map-Resolver: A network infrastructure component that accepts LISP 148 Encapsulated Map-Requests, typically from an ITR, and determines 149 whether or not the destination IP address is part of the EID 150 namespace; if it is not, a Negative Map-Reply is returned. 151 Otherwise, the Map-Resolver finds the appropriate EID-to-RLOC 152 mapping by consulting a mapping database system. 154 Encapsulated Map-Request: A LISP Map-Request carried within an 155 Encapsulated Control Message, which has an additional LISP header 156 prepended. Sent to UDP destination port 4342. The "outer" 157 addresses are globally routable IP addresses, also known as RLOCs. 158 Used by an ITR when sending to a Map-Resolver and by a Map-Server 159 when forwarding a Map-Request to an ETR. 161 Negative Map-Reply: A LISP Map-Reply that contains an empty 162 Locator-Set. Returned in response to a Map-Request if the 163 destination EID does not exist in the mapping database. 164 Typically, this means that the "EID" being requested is an IP 165 address connected to a non-LISP site. 167 Map-Register message: A LISP message sent by an ETR to a Map-Server 168 to register its associated EID-Prefixes. In addition to the set 169 of EID-Prefixes to register, the message includes one or more 170 RLOCs to be used by the Map-Server when forwarding Map-Requests 171 (re-formatted as Encapsulated Map-Requests) received through the 172 database mapping system. An ETR may request that the Map-Server 173 answer Map-Requests on its behalf by setting the "proxy Map-Reply" 174 flag (P-bit) in the message. 176 Map-Notify message: A LISP message sent by a Map-Server to an ETR 177 to confirm that a Map-Register has been received and processed. 178 An ETR requests that a Map-Notify be returned by setting the 179 "want-map-notify" flag (M-bit) in the Map-Register message. 180 Unlike a Map-Reply, a Map-Notify uses UDP port 4342 for both 181 source and destination. 183 For definitions of other terms -- notably Map-Request, Map-Reply, 184 Ingress Tunnel Router (ITR), and Egress Tunnel Router (ETR) -- please 185 consult the LISP specification [I-D.ietf-lisp-rfc6830bis]. 187 3. Basic Overview 189 A Map-Server is a device that publishes EID-Prefixes in a LISP 190 mapping database on behalf of a set of ETRs. When it receives a Map 191 Request (typically from an ITR), it consults the mapping database to 192 find an ETR that can answer with the set of RLOCs for an EID-Prefix. 193 To publish its EID-Prefixes, an ETR periodically sends Map-Register 194 messages to the Map-Server. A Map-Register message contains a list 195 of EID-Prefixes plus a set of RLOCs that can be used to reach the ETR 196 when a Map-Server needs to forward a Map-Request to it. 198 When LISP+ALT is used as the mapping database, a Map-Server connects 199 to the ALT network and acts as a "last-hop" ALT-Router. Intermediate 200 ALT-Routers forward Map-Requests to the Map-Server that advertises a 201 particular EID-Prefix, and the Map-Server forwards them to the owning 202 ETR, which responds with Map-Reply messages. 204 When LISP-DDT [I-D.ietf-lisp-ddt] is used as the mapping database, a 205 Map-Server sends the final Map-Referral messages from the Delegated 206 Database Tree. 208 A Map-Resolver receives Encapsulated Map-Requests from its client 209 ITRs and uses a mapping database system to find the appropriate ETR 210 to answer those requests. On a LISP+ALT network, a Map-Resolver acts 211 as a "first-hop" ALT-Router. It has Generic Routing Encapsulation 212 (GRE) tunnels configured to other ALT-Routers and uses BGP to learn 213 paths to ETRs for different prefixes in the LISP+ALT database. The 214 Map-Resolver uses this path information to forward Map-Requests over 215 the ALT to the correct ETRs. On a LISP-DDT network 216 [I-D.ietf-lisp-ddt], a Map-Resolver maintains a referral-cache and 217 acts as a "first-hop" DDT-node. The Map-Resolver uses the referral 218 information to forward Map-Requests. 220 Note that while it is conceivable that a non-LISP-DDT Map-Resolver 221 could cache responses to improve performance, issues surrounding 222 cache management will need to be resolved so that doing so will be 223 reliable and practical. As initially deployed, Map-Resolvers will 224 operate only in a non-caching mode, decapsulating and forwarding 225 Encapsulated Map Requests received from ITRs. Any specification of 226 caching functionality is left for future work. 228 Note that a single device can implement the functions of both a Map- 229 Server and a Map-Resolver, and in many cases the functions will be 230 co-located in that way. Also, there can be ALT-only nodes and DDT- 231 only nodes, when LISP+ALT and LISP-DDT are used, respectively, to 232 connect Map-Resolvers and Map-Servers together to make up the Mapping 233 System. 235 Detailed descriptions of the LISP packet types referenced by this 236 document may be found in [I-D.ietf-lisp-rfc6830bis]. 238 4. LISP IPv4 and IPv6 Control-Plane Packet Formats 240 The following UDP packet formats are used by the LISP control plane. 242 0 1 2 3 243 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 1 244 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 245 |Version| IHL |Type of Service| Total Length | 246 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 247 | Identification |Flags| Fragment Offset | 248 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 249 | Time to Live | Protocol = 17 | Header Checksum | 250 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 251 | Source Routing Locator | 252 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 253 | Destination Routing Locator | 254 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 255 / | Source Port | Dest Port | 256 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 257 \ | UDP Length | UDP Checksum | 258 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 259 | | 260 | LISP Message | 261 | | 262 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 264 0 1 2 3 265 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 1 266 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 267 |Version| Traffic Class | Flow Label | 268 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 269 | Payload Length | Next Header=17| Hop Limit | 270 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 271 | | 272 + + 273 | | 274 + Source Routing Locator + 275 | | 276 + + 277 | | 278 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 279 | | 280 + + 281 | | 282 + Destination Routing Locator + 283 | | 284 + + 285 | | 286 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 287 / | Source Port | Dest Port | 288 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 289 \ | UDP Length | UDP Checksum | 290 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 291 | | 292 | LISP Message | 293 | | 294 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 296 The LISP UDP-based messages are the Map-Request and Map-Reply 297 messages. When a UDP Map-Request is sent, the UDP source port is 298 chosen by the sender and the destination UDP port number is set to 299 4342. When a UDP Map-Reply is sent, the source UDP port number is 300 set to 4342 and the destination UDP port number is copied from the 301 source port of either the Map-Request or the invoking data packet. 302 Implementations MUST be prepared to accept packets when either the 303 source port or destination UDP port is set to 4342 due to NATs 304 changing port number values. 306 The 'UDP Length' field will reflect the length of the UDP header and 307 the LISP Message payload. 309 The UDP checksum is computed and set to non-zero for Map-Request, 310 Map-Reply, Map-Register, and Encapsulated Control Message (ECM) 311 control messages. It MUST be checked on receipt, and if the checksum 312 fails, the packet MUST be dropped. 314 The format of control messages includes the UDP header so the 315 checksum and length fields can be used to protect and delimit message 316 boundaries. 318 4.1. LISP Control Packet Type Allocations 320 This section will be the authoritative source for allocating LISP 321 Type values and for defining LISP control message formats. Current 322 allocations are: 324 Reserved: 0 b'0000' 325 LISP Map-Request: 1 b'0001' 326 LISP Map-Reply: 2 b'0010' 327 LISP Map-Register: 3 b'0011' 328 LISP Map-Notify: 4 b'0100' 329 LISP Map-Notify-Ack: 5 b'0101' 330 LISP Map-Referral: 6 b'0110' 331 LISP Info-Request/Reply: 7 b'0111' 332 LISP Encapsulated Control Message: 8 b'1000' 334 All LISP control-plane messages use Address Family Identifiers (AFI) 335 [AFI] or LISP Canonical Address Format (LCAF) [RFC8060] formats to 336 encode either fixed or variable length addresses. This includes 337 explicit fields in each control message or part of EID-records or 338 RLOC-records in commonly formatted messages, 340 4.2. Map-Request Message Format 342 0 1 2 3 343 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 1 344 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 345 |Type=1 |A|M|P|S|p|s|m| Reserved |L|D| IRC | Record Count | 346 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 347 | Nonce . . . | 348 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 349 | . . . Nonce | 350 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 351 | Source-EID-AFI | Source EID Address ... | 352 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 353 | ITR-RLOC-AFI 1 | ITR-RLOC Address 1 ... | 354 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 355 | ... | 356 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 357 | ITR-RLOC-AFI n | ITR-RLOC Address n ... | 358 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 359 / | Reserved | EID mask-len | EID-Prefix-AFI | 360 Rec +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 361 \ | EID-Prefix ... | 362 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 363 | Map-Reply Record ... | 364 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 366 Packet field descriptions: 368 Type: 1 (Map-Request) 370 A: This is an authoritative bit, which is set to 0 for UDP-based Map- 371 Requests sent by an ITR. It is set to 1 when an ITR wants the 372 destination site to return the Map-Reply rather than the mapping 373 database system. 375 M: This is the map-data-present bit. When set, it indicates that a 376 Map-Reply Record segment is included in the Map-Request. 378 P: This is the probe-bit, which indicates that a Map-Request SHOULD 379 be treated as a Locator reachability probe. The receiver SHOULD 380 respond with a Map-Reply with the probe-bit set, indicating that 381 the Map-Reply is a Locator reachability probe reply, with the 382 nonce copied from the Map-Request. See RLOC-Probing 383 [I-D.ietf-lisp-rfc6830bis] for more details. 385 S: This is the Solicit-Map-Request (SMR) bit. See Solicit-Map- 386 Request (SMRs) [I-D.ietf-lisp-rfc6830bis] for details. 388 p: This is the PITR bit. This bit is set to 1 when a PITR sends a 389 Map-Request. 391 s: This is the SMR-invoked bit. This bit is set to 1 when an xTR is 392 sending a Map-Request in response to a received SMR-based Map- 393 Request. 395 m: This is the LISP mobile-node m-bit. This bit is set by xTRs that 396 operate as a mobile node as defined in [I-D.meyer-lisp-mn]. 398 Reserved: This field MUST be set to 0 on transmit and MUST be 399 ignored on receipt. 401 L: This is the local-xtr bit. It is used by an xTR in a LISP site to 402 tell other xTRs in the same site that it is local to the site. 403 That is, that it is part of the RLOC-set for the LISP site. 405 D: This is the dont-map-reply bit. It is used in the SMR procedure 406 described in [I-D.ietf-lisp-rfc6830bis]. When an xTR sends an SMR 407 Map-Request message, it doesn't need a Map-Reply returned. When 408 this bit is set, the receiver of the Map-Request does not return a 409 Map-Reply. 411 IRC: This 5-bit field is the ITR-RLOC Count, which encodes the 412 additional number of ('ITR-RLOC-AFI', 'ITR-RLOC Address') fields 413 present in this message. At least one (ITR-RLOC-AFI, ITR-RLOC- 414 Address) pair MUST be encoded. Multiple 'ITR-RLOC Address' fields 415 are used, so a Map-Replier can select which destination address to 416 use for a Map-Reply. The IRC value ranges from 0 to 31. For a 417 value of 0, there is 1 ITR-RLOC address encoded; for a value of 1, 418 there are 2 ITR-RLOC addresses encoded, and so on up to 31, which 419 encodes a total of 32 ITR-RLOC addresses. 421 Record Count: This is the number of records in this Map-Request 422 message. A record is comprised of the portion of the packet that 423 is labeled 'Rec' above and occurs the number of times equal to 424 Record Count. For this version of the protocol, a receiver MUST 425 accept and process Map-Requests that contain one or more records, 426 but a sender MUST only send Map-Requests containing one record. 427 Support for requesting multiple EIDs in a single Map-Request 428 message will be specified in a future version of the protocol. 430 Nonce: This is an 8-octet random value created by the sender of the 431 Map-Request. This nonce will be returned in the Map-Reply. The 432 security of the LISP mapping protocol critically depends on the 433 strength of the nonce in the Map-Request message. The nonce 434 SHOULD be generated by a properly seeded pseudo-random (or strong 435 random) source. See [RFC4086] for advice on generating security- 436 sensitive random data. 438 Source-EID-AFI: This is the address family of the 'Source EID 439 Address' field. 441 Source EID Address: This is the EID of the source host that 442 originated the packet that caused the Map-Request. When Map- 443 Requests are used for refreshing a Map-Cache entry or for RLOC- 444 Probing, an AFI value 0 is used and this field is of zero length. 446 ITR-RLOC-AFI: This is the address family of the 'ITR-RLOC Address' 447 field that follows this field. 449 ITR-RLOC Address: This is used to give the ETR the option of 450 selecting the destination address from any address family for the 451 Map-Reply message. This address MUST be a routable RLOC address 452 of the sender of the Map-Request message. 454 EID mask-len: This is the mask length for the EID-Prefix. 456 EID-Prefix-AFI: This is the address family of the EID-Prefix 457 according to [AFI] and [RFC8060]. 459 EID-Prefix: This prefix is 4 octets for an IPv4 address family and 460 16 octets for an IPv6 address family. When a Map-Request is sent 461 by an ITR because a data packet is received for a destination 462 where there is no mapping entry, the EID-Prefix is set to the 463 destination IP address of the data packet, and the 'EID mask-len' 464 is set to 32 or 128 for IPv4 or IPv6, respectively. When an xTR 465 wants to query a site about the status of a mapping it already has 466 cached, the EID-Prefix used in the Map-Request has the same mask 467 length as the EID-Prefix returned from the site when it sent a 468 Map-Reply message. 470 Map-Reply Record: When the M-bit is set, this field is the size of a 471 single "Record" in the Map-Reply format. This Map-Reply record 472 contains the EID-to-RLOC mapping entry associated with the Source 473 EID. This allows the ETR that will receive this Map-Request to 474 cache the data if it chooses to do so. 476 4.3. EID-to-RLOC UDP Map-Request Message 478 A Map-Request is sent from an ITR when it needs a mapping for an EID, 479 wants to test an RLOC for reachability, or wants to refresh a mapping 480 before TTL expiration. For the initial case, the destination IP 481 address used for the Map-Request is the data packet's destination 482 address (i.e., the destination EID) that had a mapping cache lookup 483 failure. For the latter two cases, the destination IP address used 484 for the Map-Request is one of the RLOC addresses from the Locator-Set 485 of the Map-Cache entry. The source address is either an IPv4 or IPv6 486 RLOC address, depending on whether the Map-Request is using an IPv4 487 or IPv6 header, respectively. In all cases, the UDP source port 488 number for the Map-Request message is a 16-bit value selected by the 489 ITR/PITR, and the UDP destination port number is set to the well- 490 known destination port number 4342. A successful Map-Reply, which is 491 one that has a nonce that matches an outstanding Map-Request nonce, 492 will update the cached set of RLOCs associated with the EID-Prefix 493 range. 495 One or more Map-Request ('ITR-RLOC-AFI', 'ITR-RLOC-Address') fields 496 MUST be filled in by the ITR. The number of fields (minus 1) encoded 497 MUST be placed in the 'IRC' field. The ITR MAY include all locally 498 configured Locators in this list or just provide one locator address 499 from each address family it supports. If the ITR erroneously 500 provides no ITR-RLOC addresses, the Map-Replier MUST drop the Map- 501 Request. 503 Map-Requests can also be LISP encapsulated using UDP destination 504 port 4342 with a LISP Type value set to "Encapsulated Control 505 Message", when sent from an ITR to a Map-Resolver. Likewise, Map- 506 Requests are LISP encapsulated the same way from a Map-Server to an 507 ETR. Details on Encapsulated Map-Requests and Map-Resolvers can be 508 found in Section 4.8. 510 Map-Requests MUST be rate-limited. It is RECOMMENDED that a Map- 511 Request for the same EID-Prefix be sent no more than once per second. 513 An ITR that is configured with mapping database information (i.e., it 514 is also an ETR) MAY optionally include those mappings in a Map- 515 Request. When an ETR configured to accept and verify such 516 "piggybacked" mapping data receives such a Map-Request and it does 517 not have this mapping in the map-cache, it MAY originate a "verifying 518 Map-Request", addressed to the map-requesting ITR and the ETR MAY add 519 a Map-Cache entry. If the ETR has a Map-Cache entry that matches the 520 "piggybacked" EID and the RLOC is in the Locator-Set for the entry, 521 then it may send the "verifying Map-Request" directly to the 522 originating Map-Request source. If the RLOC is not in the Locator- 523 Set, then the ETR MUST send the "verifying Map-Request" to the 524 "piggybacked" EID. Doing this forces the "verifying Map-Request" to 525 go through the mapping database system to reach the authoritative 526 source of information about that EID, guarding against RLOC-spoofing 527 in the "piggybacked" mapping data. 529 4.4. Map-Reply Message Format 531 0 1 2 3 532 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 1 533 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 534 |Type=2 |P|E|S| Reserved | Record Count | 535 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 536 | Nonce . . . | 537 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 538 | . . . Nonce | 539 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 540 | | Record TTL | 541 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 542 R | Locator Count | EID mask-len | ACT |A| Reserved | 543 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 544 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 545 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 546 r | EID-Prefix | 547 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 548 | /| Priority | Weight | M Priority | M Weight | 549 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 550 | o | Unused Flags |L|p|R| Loc-AFI | 551 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 552 | \| Locator | 553 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 555 Packet field descriptions: 557 Type: 2 (Map-Reply) 559 P: This is the probe-bit, which indicates that the Map-Reply is in 560 response to a Locator reachability probe Map-Request. The 'Nonce' 561 field MUST contain a copy of the nonce value from the original 562 Map-Request. See RLOC-probing [I-D.ietf-lisp-rfc6830bis] for more 563 details. 565 E: This bit indicates that the ETR that sends this Map-Reply message 566 is advertising that the site is enabled for the Echo-Nonce Locator 567 reachability algorithm. See Echo-Nonce [I-D.ietf-lisp-rfc6830bis] 568 for more details. 570 S: This is the Security bit. When set to 1, the following 571 authentication information will be appended to the end of the Map- 572 Reply. The details of signing a Map-Reply message can be found in 573 [I-D.ietf-lisp-sec]. 575 0 1 2 3 576 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 1 577 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 578 | AD Type | Authentication Data Content . . . | 579 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 581 Reserved: This field MUST be set to 0 on transmit and MUST be 582 ignored on receipt. 584 Record Count: This is the number of records in this reply message. 585 A record is comprised of that portion of the packet labeled 586 'Record' above and occurs the number of times equal to Record 587 Count. 589 Nonce: This is a 24-bit value set in a Data-Probe packet, or a 590 64-bit value from the Map-Request is echoed in this 'Nonce' field 591 of the Map-Reply. When a 24-bit value is supplied, it resides in 592 the low-order 64 bits of the 'Nonce' field. 594 Record TTL: This is the time in minutes the recipient of the Map- 595 Reply will store the mapping. If the TTL is 0, the entry SHOULD 596 be removed from the cache immediately. If the value is 597 0xffffffff, the recipient can decide locally how long to store the 598 mapping. 600 Locator Count: This is the number of Locator entries. A Locator 601 entry comprises what is labeled above as 'Loc'. The Locator count 602 can be 0, indicating that there are no Locators for the EID- 603 Prefix. 605 EID mask-len: This is the mask length for the EID-Prefix. 607 ACT: This 3-bit field describes Negative Map-Reply actions. In any 608 other message type, these bits are set to 0 and ignored on 609 receipt. These bits are used only when the 'Locator Count' field 610 is set to 0. The action bits are encoded only in Map-Reply 611 messages. The actions defined are used by an ITR or PITR when a 612 destination EID matches a negative Map-Cache entry. Unassigned 613 values should cause a Map-Cache entry to be created, and when 614 packets match this negative cache entry, they will be dropped. 615 The current assigned values are: 617 (0) No-Action: The map-cache is kept alive, and no packet 618 encapsulation occurs. 620 (1) Natively-Forward: The packet is not encapsulated or dropped 621 but natively forwarded. 623 (2) Send-Map-Request: The packet invokes sending a Map-Request. 625 (3) Drop/No-Reason: A packet that matches this map-cache entry is 626 dropped. An ICMP Destination Unreachable message SHOULD be 627 sent. 629 (4) Drop/Policy-Denied: A packet that matches this map-cache 630 entry is dropped. The reason for the Drop action is that a 631 Map-Request for the target-EID is being policy denied by 632 either an xTR or the mapping system. 634 (5) Drop/Authentication-Failure: A packet that matches this map- 635 cache entry is dropped. The reason for the Drop action is 636 that a Map-Request for the target-EID fails an authentication 637 verification-check by either an xTR or the mapping system. 639 A: The Authoritative bit, when sent, is always set to 1 by an ETR. 640 When a Map-Server is proxy Map-Replying for a LISP site, the 641 Authoritative bit is set to 0. This indicates to requesting ITRs 642 that the Map-Reply was not originated by a LISP node managed at 643 the site that owns the EID-Prefix. 645 Map-Version Number: When this 12-bit value is non-zero, the Map- 646 Reply sender is informing the ITR what the version number is for 647 the EID record contained in the Map-Reply. The ETR can allocate 648 this number internally but MUST coordinate this value with other 649 ETRs for the site. When this value is 0, there is no versioning 650 information conveyed. The Map-Version Number can be included in 651 Map-Request and Map-Register messages. See Map-Versioning 652 [I-D.ietf-lisp-rfc6830bis] for more details. 654 EID-Prefix-AFI: Address family of the EID-Prefix according to [AFI] 655 and [RFC8060]. 657 EID-Prefix: This prefix is 4 octets for an IPv4 address family and 658 16 octets for an IPv6 address family. 660 Priority: Each RLOC is assigned a unicast Priority. Lower values 661 are more preferable. When multiple RLOCs have the same Priority, 662 they MAY be used in a load-split fashion. A value of 255 means 663 the RLOC MUST NOT be used for unicast forwarding. 665 Weight: When priorities are the same for multiple RLOCs, the Weight 666 indicates how to balance unicast traffic between them. Weight is 667 encoded as a relative weight of total unicast packets that match 668 the mapping entry. For example, if there are 4 Locators in a 669 Locator-Set, where the Weights assigned are 30, 20, 20, and 10, 670 the first Locator will get 37.5% of the traffic, the 2nd and 3rd 671 Locators will get 25% of the traffic, and the 4th Locator will get 672 12.5% of the traffic. If all Weights for a Locator-Set are equal, 673 the receiver of the Map-Reply will decide how to load-split the 674 traffic. See RLOC-hashing [I-D.ietf-lisp-rfc6830bis] for a 675 suggested hash algorithm to distribute the load across Locators 676 with the same Priority and equal Weight values. 678 M Priority: Each RLOC is assigned a multicast Priority used by an 679 ETR in a receiver multicast site to select an ITR in a source 680 multicast site for building multicast distribution trees. A value 681 of 255 means the RLOC MUST NOT be used for joining a multicast 682 distribution tree. For more details, see [RFC6831]. 684 M Weight: When priorities are the same for multiple RLOCs, the 685 Weight indicates how to balance building multicast distribution 686 trees across multiple ITRs. The Weight is encoded as a relative 687 weight (similar to the unicast Weights) of the total number of 688 trees built to the source site identified by the EID-Prefix. If 689 all Weights for a Locator-Set are equal, the receiver of the Map- 690 Reply will decide how to distribute multicast state across ITRs. 691 For more details, see [RFC6831]. 693 Unused Flags: These are set to 0 when sending and ignored on 694 receipt. 696 L: When this bit is set, the Locator is flagged as a local Locator to 697 the ETR that is sending the Map-Reply. When a Map-Server is doing 698 proxy Map-Replying for a LISP site, the L-bit is set to 0 for all 699 Locators in this Locator-Set. 701 p: When this bit is set, an ETR informs the RLOC-Probing ITR that the 702 locator address for which this bit is set is the one being RLOC- 703 probed and MAY be different from the source address of the Map- 704 Reply. An ITR that RLOC-probes a particular Locator MUST use this 705 Locator for retrieving the data structure used to store the fact 706 that the Locator is reachable. The p-bit is set for a single 707 Locator in the same Locator-Set. If an implementation sets more 708 than one p-bit erroneously, the receiver of the Map-Reply MUST 709 select the first Locator. The p-bit MUST NOT be set for Locator- 710 Set records sent in Map-Request and Map-Register messages. 712 R: This is set when the sender of a Map-Reply has a route to the 713 Locator in the Locator data record. This receiver may find this 714 useful to know if the Locator is up but not necessarily reachable 715 from the receiver's point of view. See also EID-Reachability 716 [I-D.ietf-lisp-rfc6830bis] for another way the R-bit may be used. 718 Locator: This is an IPv4 or IPv6 address (as encoded by the 'Loc- 719 AFI' field) assigned to an ETR. Note that the destination RLOC 720 address MAY be an anycast address. A source RLOC can be an 721 anycast address as well. The source or destination RLOC MUST NOT 722 be the broadcast address (255.255.255.255 or any subnet broadcast 723 address known to the router) and MUST NOT be a link-local 724 multicast address. The source RLOC MUST NOT be a multicast 725 address. The destination RLOC SHOULD be a multicast address if it 726 is being mapped from a multicast destination EID. 728 4.5. EID-to-RLOC UDP Map-Reply Message 730 A Map-Reply returns an EID-Prefix with a prefix length that is less 731 than or equal to the EID being requested. The EID being requested is 732 either from the destination field of an IP header of a Data-Probe or 733 the EID record of a Map-Request. The RLOCs in the Map-Reply are 734 globally routable IP addresses of all ETRs for the LISP site. Each 735 RLOC conveys status reachability but does not convey path 736 reachability from a requester's perspective. Separate testing of 737 path reachability is required. See RLOC-reachability 738 [I-D.ietf-lisp-rfc6830bis] for details. 740 Note that a Map-Reply may contain different EID-Prefix granularity 741 (prefix + length) than the Map-Request that triggers it. This might 742 occur if a Map-Request were for a prefix that had been returned by an 743 earlier Map-Reply. In such a case, the requester updates its cache 744 with the new prefix information and granularity. For example, a 745 requester with two cached EID-Prefixes that are covered by a Map- 746 Reply containing one less-specific prefix replaces the entry with the 747 less-specific EID-Prefix. Note that the reverse, replacement of one 748 less-specific prefix with multiple more-specific prefixes, can also 749 occur, not by removing the less-specific prefix but rather by adding 750 the more-specific prefixes that, during a lookup, will override the 751 less-specific prefix. 753 When an ETR is configured with overlapping EID-Prefixes, a Map- 754 Request with an EID that best matches any EID-Prefix MUST be returned 755 in a single Map-Reply message. For instance, if an ETR had database 756 mapping entries for EID-Prefixes: 758 10.0.0.0/8 759 10.1.0.0/16 760 10.1.1.0/24 761 10.1.2.0/24 763 A Map-Request for EID 10.1.1.1 would cause a Map-Reply with a record 764 count of 1 to be returned with a mapping record EID-Prefix of 765 10.1.1.0/24. 767 A Map-Request for EID 10.1.5.5 would cause a Map-Reply with a record 768 count of 3 to be returned with mapping records for EID-Prefixes 769 10.1.0.0/16, 10.1.1.0/24, and 10.1.2.0/24. 771 Note that not all overlapping EID-Prefixes need to be returned but 772 only the more-specific entries (note that in the second example above 773 10.0.0.0/8 was not returned for requesting EID 10.1.5.5) for the 774 matching EID-Prefix of the requesting EID. When more than one EID- 775 Prefix is returned, all SHOULD use the same Time to Live value so 776 they can all time out at the same time. When a more-specific EID- 777 Prefix is received later, its Time to Live value in the Map-Reply 778 record can be stored even when other less-specific entries exist. 779 When a less-specific EID-Prefix is received later, its map-cache 780 expiration time SHOULD be set to the minimum expiration time of any 781 more-specific EID-Prefix in the map-cache. This is done so the 782 integrity of the EID-Prefix set is wholly maintained and so no more- 783 specific entries are removed from the map-cache while keeping less- 784 specific entries. 786 Map-Replies SHOULD be sent for an EID-Prefix no more often than once 787 per second to the same requesting router. For scalability, it is 788 expected that aggregation of EID addresses into EID-Prefixes will 789 allow one Map-Reply to satisfy a mapping for the EID addresses in the 790 prefix range, thereby reducing the number of Map-Request messages. 792 Map-Reply records can have an empty Locator-Set. A Negative Map- 793 Reply is a Map-Reply with an empty Locator-Set. Negative Map-Replies 794 convey special actions by the sender to the ITR or PITR that have 795 solicited the Map-Reply. There are two primary applications for 796 Negative Map-Replies. The first is for a Map-Resolver to instruct an 797 ITR or PITR when a destination is for a LISP site versus a non-LISP 798 site, and the other is to source quench Map-Requests that are sent 799 for non-allocated EIDs. 801 For each Map-Reply record, the list of Locators in a Locator-Set MUST 802 appear in the same order for each ETR that originates a Map-Reply 803 message. The Locator-Set MUST be sorted in order of ascending IP 804 address where an IPv4 locator address is considered numerically 'less 805 than' an IPv6 locator address. 807 When sending a Map-Reply message, the destination address is copied 808 from one of the 'ITR-RLOC' fields from the Map-Request. The ETR can 809 choose a locator address from one of the address families it 810 supports. For Data-Probes, the destination address of the Map-Reply 811 is copied from the source address of the Data-Probe message that is 812 invoking the reply. The source address of the Map-Reply is one of 813 the local IP addresses chosen to allow Unicast Reverse Path 814 Forwarding (uRPF) checks to succeed in the upstream service provider. 816 The destination port of a Map-Reply message is copied from the source 817 port of the Map-Request or Data-Probe, and the source port of the 818 Map-Reply message is set to the well-known UDP port 4342. 820 4.6. Map-Register Message Format 822 This section specifies the encoding format for the Map-Register 823 message. The message is sent in UDP with a destination UDP port of 824 4342 and a randomly selected UDP source port number. 826 The Map-Register message format is: 828 0 1 2 3 829 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 1 830 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 831 |Type=3 |P|S|I| Reserved |E|T|a|m|M| Record Count | 832 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 833 | Nonce . . . | 834 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 835 | . . . Nonce | 836 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 837 | Key ID | Authentication Data Length | 838 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 839 ~ Authentication Data ~ 840 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 841 | | Record TTL | 842 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 843 R | Locator Count | EID mask-len | ACT |A| Reserved | 844 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 845 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 846 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 847 r | EID-Prefix | 848 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 849 | /| Priority | Weight | M Priority | M Weight | 850 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 851 | o | Unused Flags |L|p|R| Loc-AFI | 852 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 853 | \| Locator | 854 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 856 Packet field descriptions: 858 Type: 3 (Map-Register) 860 P: This is the proxy Map-Reply bit. When set to 1, an ETR sends a 861 Map-Register message requesting the Map-Server to proxy a Map- 862 Reply. The Map-Server will send non-authoritative Map-Replies on 863 behalf of the ETR. 865 S: This is the security-capable bit. When set, the procedures from 866 [I-D.ietf-lisp-sec] are supported. 868 I: This is the xTR-ID bit. When this bit is set, what is appended to 869 the Map-Register is a 128-bit xTR router-ID and then a 64-bit 870 site-ID. See LISP NAT-Traversal procedures in 871 [I-D.ermagan-lisp-nat-traversal] for details. 873 Reserved: This field MUST be set to 0 on transmit and MUST be 874 ignored on receipt. 876 E: This is the Map-Register EID-notify bit. This is used by a First- 877 Hop-Router (FHR) which discovers a dynamic-EID. This EID-notify 878 based Map-Register is sent by the FHR to the same site xTR that 879 propogates the Map-Register to the mapping system. The site xTR 880 keeps state to later Map-Notify the FHR after the EID has moves 881 away. See [I-D.portoles-lisp-eid-mobility] for a detailed use- 882 case. 884 T: This is the use-TTL for timeout bit. When set to 1, the xTR wants 885 the Map-Server to time out registrations based on the value in the 886 "Record TTL" field of this message. 888 a: This is the merge-request bit. When set to 1, the xTR requests to 889 merge RLOC-records from different xTRs registering the same EID- 890 record. See signal-free multicast 891 [I-D.ietf-lisp-signal-free-multicast] for one use case example. 893 m: This is the mobile-node bit. When set to 1, the registering xTR 894 supports the procuedures in [I-D.meyer-lisp-mn]. 896 M: This is the want-map-notify bit. When set to 1, an ETR is 897 requesting a Map-Notify message to be returned in response to 898 sending a Map-Register message. The Map-Notify message sent by a 899 Map-Server is used to acknowledge receipt of a Map-Register 900 message. 902 Record Count: This is the number of records in this Map-Register 903 message. A record is comprised of that portion of the packet 904 labeled 'Record' above and occurs the number of times equal to 905 Record Count. 907 Nonce: This 8-octet 'Nonce' field is set to 0 in Map-Register 908 messages. Since the Map-Register message is authenticated, the 909 'Nonce' field is not currently used for any security function but 910 may be in the future as part of an anti-replay solution. 912 Key ID: This is a configured ID to find the configured Message 913 Authentication Code (MAC) algorithm and key value used for the 914 authentication function. See Key ID Numbers in 915 [I-D.ietf-lisp-rfc6830bis] for codepoint assignments. 917 Authentication Data Length: This is the length in octets of the 918 'Authentication Data' field that follows this field. The length 919 of the 'Authentication Data' field is dependent on the MAC 920 algorithm used. The length field allows a device that doesn't 921 know the MAC algorithm to correctly parse the packet. 923 Authentication Data: This is the message digest used from the output 924 of the MAC algorithm. The entire Map-Register payload is 925 authenticated with this field preset to 0. After the MAC is 926 computed, it is placed in this field. Implementations of this 927 specification MUST include support for HMAC-SHA-1-96 [RFC2404], 928 and support for HMAC-SHA-256-128 [RFC4868] is RECOMMENDED. 930 The definition of the rest of the Map-Register can be found in 931 Section 4.4. 933 4.7. Map-Notify/Map-Notify-Ack Message Format 935 This section specifies the encoding format for the Map-Notify and 936 Map-Notify-Ack messages. The messages are sent inside a UDP packet 937 with source and destination UDP ports equal to 4342. 939 The Map-Notify and Map-Notify-Ack message formats are: 941 0 1 2 3 942 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 1 943 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 944 |Type=4/5| Reserved | Record Count | 945 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 946 | Nonce . . . | 947 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 948 | . . . Nonce | 949 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 950 | Key ID | Authentication Data Length | 951 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 952 ~ Authentication Data ~ 953 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 954 | | Record TTL | 955 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 956 R | Locator Count | EID mask-len | ACT |A| Reserved | 957 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 958 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 959 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 960 r | EID-Prefix | 961 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 962 | /| Priority | Weight | M Priority | M Weight | 963 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 964 | o | Unused Flags |L|p|R| Loc-AFI | 965 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 966 | \| Locator | 967 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 969 Packet field descriptions: 971 Type: 4/5 (Map-Notify/Map-Notify-Ack) 973 The Map-Notify message has the same contents as a Map-Register 974 message. See the Map-Register section for field descriptions. 976 The Map-Notify-Ack message has the same contents as a Map-Notify 977 message. It is used to acknowledge the receipt of a Map-Notify and 978 for the sender to stop retransmitting a Map-Notify with the same 979 nonce. 981 4.8. Encapsulated Control Message Format 983 An Encapsulated Control Message (ECM) is used to encapsulate control 984 packets sent between xTRs and the mapping database system. 986 0 1 2 3 987 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 1 988 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 989 / | IPv4 or IPv6 Header | 990 OH | (uses RLOC addresses) | 991 \ | | 992 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 993 / | Source Port = xxxx | Dest Port = 4342 | 994 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 995 \ | UDP Length | UDP Checksum | 996 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 997 LH |Type=8 |S|D|E|M| Reserved | 998 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 999 / | IPv4 or IPv6 Header | 1000 IH | (uses RLOC or EID addresses) | 1001 \ | | 1002 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1003 / | Source Port = xxxx | Dest Port = yyyy | 1004 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1005 \ | UDP Length | UDP Checksum | 1006 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1007 LCM | LISP Control Message | 1008 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1010 Packet header descriptions: 1012 OH: The outer IPv4 or IPv6 header, which uses RLOC addresses in the 1013 source and destination header address fields. 1015 UDP: The outer UDP header with destination port 4342. The source 1016 port is randomly allocated. The checksum field MUST be non- 1017 zero. 1019 LH: Type 8 is defined to be a "LISP Encapsulated Control Message", 1020 and what follows is either an IPv4 or IPv6 header as encoded by 1021 the first 4 bits after the 'Reserved' field. 1023 Type: 8 (Encapsulated Control Message (ECM)) 1025 S: This is the Security bit. When set to 1, the procedures from 1026 [I-D.ietf-lisp-sec] are followed. 1028 D: This is the DDT-bit. When set to 1, the sender is requesting a 1029 Map-Referral message to be returned. The details of this 1030 procedure are described in [I-D.ietf-lisp-ddt]. 1032 E: This is the to-ETR bit. When set to 1, the Map-Server's 1033 intention is to forward the ECM to an authoritative ETR. 1035 M: This is the to-MS bit. When set to 1, a Map-Request is being 1036 sent to a co-located Map-Resolver and Map-Server where the 1037 message can be processed directly by the Map-Server versus the 1038 Map-Resolver using the LISP-DDT procedures in 1039 [I-D.ietf-lisp-ddt]. 1041 0 1 2 3 1042 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 1043 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1044 | AD Type | Authentication Data Content . . . | 1045 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1047 IH: The inner IPv4 or IPv6 header, which can use either RLOC or EID 1048 addresses in the header address fields. When a Map-Request is 1049 encapsulated in this packet format, the destination address in 1050 this header is an EID. 1052 UDP: The inner UDP header, where the port assignments depend on the 1053 control packet being encapsulated. When the control packet is 1054 a Map-Request or Map-Register, the source port is selected by 1055 the ITR/PITR and the destination port is 4342. When the 1056 control packet is a Map-Reply, the source port is 4342 and the 1057 destination port is assigned from the source port of the 1058 invoking Map-Request. Port number 4341 MUST NOT be assigned to 1059 either port. The checksum field MUST be non-zero. 1061 LCM: The format is one of the control message formats described in 1062 this section. At this time, only Map-Request messages are 1063 allowed to be encapsulated. In the future, PIM Join/Prune 1064 messages [RFC6831] might be allowed. Encapsulating other types 1065 of LISP control messages is for further study. When Map- 1066 Requests are sent for RLOC-Probing purposes (i.e., the probe- 1067 bit is set), they MUST NOT be sent inside Encapsulated Control 1068 Messages. 1070 5. Interactions with Other LISP Components 1072 5.1. ITR EID-to-RLOC Mapping Resolution 1074 An ITR is configured with one or more Map-Resolver addresses. These 1075 addresses are "Locators" (or RLOCs) and must be routable on the 1076 underlying core network; they must not need to be resolved through 1077 LISP EID-to-RLOC mapping, as that would introduce a circular 1078 dependency. When using a Map-Resolver, an ITR does not need to 1079 connect to any other database mapping system. In particular, the ITR 1080 need not connect to the LISP+ALT infrastructure or implement the BGP 1081 and GRE protocols that it uses. 1083 An ITR sends an Encapsulated Map-Request to a configured Map-Resolver 1084 when it needs an EID-to-RLOC mapping that is not found in its local 1085 map-cache. Using the Map-Resolver greatly reduces both the 1086 complexity of the ITR implementation and the costs associated with 1087 its operation. 1089 In response to an Encapsulated Map-Request, the ITR can expect one of 1090 the following: 1092 o An immediate Negative Map-Reply (with action code of "Natively- 1093 Forward", 15-minute Time to Live (TTL)) from the Map-Resolver if 1094 the Map-Resolver can determine that the requested EID does not 1095 exist. The ITR saves the EID-Prefix returned in the Map-Reply in 1096 its cache, marks it as non-LISP-capable, and knows not to attempt 1097 LISP encapsulation for destinations matching it. 1099 o A Negative Map-Reply, with action code of "Natively-Forward", from 1100 a Map-Server that is authoritative for an EID-Prefix that matches 1101 the requested EID but that does not have an actively registered, 1102 more-specific ID-prefix. In this case, the requested EID is said 1103 to match a "hole" in the authoritative EID-Prefix. If the 1104 requested EID matches a more-specific EID-Prefix that has been 1105 delegated by the Map-Server but for which no ETRs are currently 1106 registered, a 1-minute TTL is returned. If the requested EID 1107 matches a non-delegated part of the authoritative EID-Prefix, then 1108 it is not a LISP EID and a 15-minute TTL is returned. See 1109 Section 5.2 for discussion of aggregate EID-Prefixes and details 1110 of Map-Server EID-Prefix matching. 1112 o A LISP Map-Reply from the ETR that owns the EID-to-RLOC mapping or 1113 possibly from a Map-Server answering on behalf of the ETR. See 1114 Section 5.4 for more details on Map-Resolver message processing. 1116 Note that an ITR may be configured to both use a Map-Resolver and to 1117 participate in a LISP+ALT logical network. In such a situation, the 1118 ITR should send Map-Requests through the ALT network for any EID- 1119 Prefix learned via ALT BGP. Such a configuration is expected to be 1120 very rare, since there is little benefit to using a Map-Resolver if 1121 an ITR is already using LISP+ALT. There would be, for example, no 1122 need for such an ITR to send a Map-Request to a possibly non-existent 1123 EID (and rely on Negative Map-Replies) if it can consult the ALT 1124 database to verify that an EID-Prefix is present before sending that 1125 Map-Request. 1127 5.2. EID-Prefix Configuration and ETR Registration 1129 An ETR publishes its EID-Prefixes on a Map-Server by sending LISP 1130 Map-Register messages. A Map-Register message includes 1131 authentication data, so prior to sending a Map-Register message, the 1132 ETR and Map-Server must be configured with a shared secret or other 1133 relevant authentication information. A Map-Server's configuration 1134 must also include a list of the EID-Prefixes for which each ETR is 1135 authoritative. Upon receipt of a Map-Register from an ETR, a Map- 1136 Server accepts only EID-Prefixes that are configured for that ETR. 1137 Failure to implement such a check would leave the mapping system 1138 vulnerable to trivial EID-Prefix hijacking attacks. As developers 1139 and operators gain experience with the mapping system, additional, 1140 stronger security measures may be added to the registration process. 1142 In addition to the set of EID-Prefixes defined for each ETR that may 1143 register, a Map-Server is typically also configured with one or more 1144 aggregate prefixes that define the part of the EID numbering space 1145 assigned to it. When LISP+ALT is the database in use, aggregate EID- 1146 Prefixes are implemented as discard routes and advertised into ALT 1147 BGP. The existence of aggregate EID-Prefixes in a Map-Server's 1148 database means that it may receive Map Requests for EID-Prefixes that 1149 match an aggregate but do not match a registered prefix; Section 5.3 1150 describes how this is handled. 1152 Map-Register messages are sent periodically from an ETR to a Map- 1153 Server with a suggested interval between messages of one minute. A 1154 Map-Server should time out and remove an ETR's registration if it has 1155 not received a valid Map-Register message within the past 1156 three minutes. When first contacting a Map-Server after restart or 1157 changes to its EID-to-RLOC database mappings, an ETR may initially 1158 send Map-Register messages at an increased frequency, up to one every 1159 20 seconds. This "quick registration" period is limited to 1160 five minutes in duration. 1162 An ETR may request that a Map-Server explicitly acknowledge receipt 1163 and processing of a Map-Register message by setting the "want-map- 1164 notify" (M-bit) flag. A Map-Server that receives a Map-Register with 1165 this flag set will respond with a Map-Notify message. Typical use of 1166 this flag by an ETR would be to set it for Map-Register messages sent 1167 during the initial "quick registration" with a Map-Server but then 1168 set it only occasionally during steady-state maintenance of its 1169 association with that Map-Server. Note that the Map-Notify message 1170 is sent to UDP destination port 4342, not to the source port 1171 specified in the original Map-Register message. 1173 Note that a one-minute minimum registration interval during 1174 maintenance of an ETR-Map-Server association places a lower bound on 1175 how quickly and how frequently a mapping database entry can be 1176 updated. This may have implications for what sorts of mobility can 1177 be supported directly by the mapping system; shorter registration 1178 intervals or other mechanisms might be needed to support faster 1179 mobility in some cases. For a discussion on one way that faster 1180 mobility may be implemented for individual devices, please see 1181 [I-D.meyer-lisp-mn] 1183 An ETR may also request, by setting the "proxy Map-Reply" flag 1184 (P-bit) in the Map-Register message, that a Map-Server answer Map- 1185 Requests instead of forwarding them to the ETR. See 1186 [I-D.ietf-lisp-rfc6830bis] for details on how the Map-Server sets 1187 certain flags (such as those indicating whether the message is 1188 authoritative and how returned Locators should be treated) when 1189 sending a Map-Reply on behalf of an ETR. When an ETR requests proxy 1190 reply service, it should include all RLOCs for all ETRs for the EID- 1191 Prefix being registered, along with the routable flag ("R-bit") 1192 setting for each RLOC. The Map-Server includes all of this 1193 information in Map-Reply messages that it sends on behalf of the ETR. 1194 This differs from a non-proxy registration, since the latter need 1195 only provide one or more RLOCs for a Map-Server to use for forwarding 1196 Map-Requests; the registration information is not used in Map- 1197 Replies, so it being incomplete is not incorrect. 1199 An ETR that uses a Map-Server to publish its EID-to-RLOC mappings 1200 does not need to participate further in the mapping database 1201 protocol(s). When using a LISP+ALT mapping database, for example, 1202 this means that the ETR does not need to implement GRE or BGP, which 1203 greatly simplifies its configuration and reduces its cost of 1204 operation. 1206 Note that use of a Map-Server does not preclude an ETR from also 1207 connecting to the mapping database (i.e., it could also connect to 1208 the LISP+ALT network), but doing so doesn't seem particularly useful, 1209 as the whole purpose of using a Map-Server is to avoid the complexity 1210 of the mapping database protocols. 1212 5.3. Map-Server Processing 1214 Once a Map-Server has EID-Prefixes registered by its client ETRs, it 1215 can accept and process Map-Requests for them. 1217 In response to a Map-Request (received over the ALT if LISP+ALT is in 1218 use), the Map-Server first checks to see if the destination EID 1219 matches a configured EID-Prefix. If there is no match, the Map- 1220 Server returns a Negative Map-Reply with action code "Natively- 1221 Forward" and a 15-minute TTL. This may occur if a Map Request is 1222 received for a configured aggregate EID-Prefix for which no more- 1223 specific EID-Prefix exists; it indicates the presence of a non-LISP 1224 "hole" in the aggregate EID-Prefix. 1226 Next, the Map-Server checks to see if any ETRs have registered the 1227 matching EID-Prefix. If none are found, then the Map-Server returns 1228 a Negative Map-Reply with action code "Natively-Forward" and a 1229 1-minute TTL. 1231 If any of the registered ETRs for the EID-Prefix have requested proxy 1232 reply service, then the Map-Server answers the request instead of 1233 forwarding it. It returns a Map-Reply with the EID-Prefix, RLOCs, 1234 and other information learned through the registration process. 1236 If none of the ETRs have requested proxy reply service, then the Map- 1237 Server re-encapsulates and forwards the resulting Encapsulated Map- 1238 Request to one of the registered ETRs. It does not otherwise alter 1239 the Map-Request, so any Map-Reply sent by the ETR is returned to the 1240 RLOC in the Map-Request, not to the Map-Server. Unless also acting 1241 as a Map-Resolver, a Map-Server should never receive Map-Replies; any 1242 such messages should be discarded without response, perhaps 1243 accompanied by the logging of a diagnostic message if the rate of 1244 Map-Replies is suggestive of malicious traffic. 1246 5.4. Map-Resolver Processing 1248 Upon receipt of an Encapsulated Map-Request, a Map-Resolver 1249 decapsulates the enclosed message and then searches for the requested 1250 EID in its local database of mapping entries (statically configured 1251 or learned from associated ETRs if the Map-Resolver is also a Map- 1252 Server offering proxy reply service). If it finds a matching entry, 1253 it returns a LISP Map-Reply with the known mapping. 1255 If the Map-Resolver does not have the mapping entry and if it can 1256 determine that the EID is not in the mapping database (for example, 1257 if LISP+ALT is used, the Map-Resolver will have an ALT forwarding 1258 table that covers the full EID space), it immediately returns a 1259 negative LISP Map-Reply, with action code "Natively-Forward" and a 1260 15-minute TTL. To minimize the number of negative cache entries 1261 needed by an ITR, the Map-Resolver should return the least-specific 1262 prefix that both matches the original query and does not match any 1263 EID-Prefix known to exist in the LISP-capable infrastructure. 1265 If the Map-Resolver does not have sufficient information to know 1266 whether the EID exists, it needs to forward the Map-Request to 1267 another device that has more information about the EID being 1268 requested. To do this, it forwards the unencapsulated Map-Request, 1269 with the original ITR RLOC as the source, to the mapping database 1270 system. Using LISP+ALT, the Map-Resolver is connected to the ALT 1271 network and sends the Map-Request to the next ALT hop learned from 1272 its ALT BGP neighbors. The Map-Resolver does not send any response 1273 to the ITR; since the source RLOC is that of the ITR, the ETR or Map- 1274 Server that receives the Map-Request over the ALT and responds will 1275 do so directly to the ITR. 1277 5.4.1. Anycast Map-Resolver Operation 1279 A Map-Resolver can be set up to use "anycast", where the same address 1280 is assigned to multiple Map-Resolvers and is propagated through IGP 1281 routing, to facilitate the use of a topologically close Map-Resolver 1282 by each ITR. 1284 Note that Map-Server associations with ETRs should not use anycast 1285 addresses, as registrations need to be established between an ETR and 1286 a specific set of Map-Servers, each identified by a specific 1287 registration association. 1289 6. Security Considerations 1291 The 2-way LISP header nonce exchange documented in 1292 [I-D.ietf-lisp-rfc6830bis] can be used to avoid ITR spoofing attacks. 1294 To publish an authoritative EID-to-RLOC mapping with a Map-Server, an 1295 ETR includes authentication data that is a hash of the message using 1296 a pair-wise shared key. An implementation must support use of HMAC- 1297 SHA-1-96 [RFC2104] and should support use of HMAC-SHA-256-128 1298 [RFC6234] (SHA-256 truncated to 128 bits). 1300 As noted in Section 5.2, a Map-Server should verify that all EID- 1301 Prefixes registered by an ETR match the configuration stored on the 1302 Map-Server. 1304 The currently defined authentication mechanism for Map-Register 1305 messages does not provide protection against "replay" attacks by a 1306 "man-in-the-middle". Additional work is needed in this area. 1308 [I-D.ietf-lisp-sec] defines a proposed mechanism for providing origin 1309 authentication, integrity, anti-replay protection, and prevention of 1310 man-in-the-middle and "overclaiming" attacks on the Map-Request/Map- 1311 Reply exchange. Work is ongoing on this and other proposals for 1312 resolving these open security issues. 1314 While beyond the scope of securing an individual Map-Server or Map- 1315 Resolver, it should be noted that a BGP-based LISP+ALT network (if 1316 ALT is used as the mapping database infrastructure) can take 1317 advantage of standards work on adding security to BGP. 1319 A complete LISP threat analysis has been published in [RFC7835]. 1320 Please refer to it for more security related details. 1322 7. References 1324 7.1. Normative References 1326 [RFC1035] Mockapetris, P., "Domain names - implementation and 1327 specification", STD 13, RFC 1035, DOI 10.17487/RFC1035, 1328 November 1987, . 1330 [RFC2104] Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed- 1331 Hashing for Message Authentication", RFC 2104, 1332 DOI 10.17487/RFC2104, February 1997, 1333 . 1335 [RFC2404] Madson, C. and R. Glenn, "The Use of HMAC-SHA-1-96 within 1336 ESP and AH", RFC 2404, DOI 10.17487/RFC2404, November 1337 1998, . 1339 [RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, 1340 "Randomness Requirements for Security", BCP 106, RFC 4086, 1341 DOI 10.17487/RFC4086, June 2005, 1342 . 1344 [RFC4107] Bellovin, S. and R. Housley, "Guidelines for Cryptographic 1345 Key Management", BCP 107, RFC 4107, DOI 10.17487/RFC4107, 1346 June 2005, . 1348 [RFC4868] Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-SHA- 1349 384, and HMAC-SHA-512 with IPsec", RFC 4868, 1350 DOI 10.17487/RFC4868, May 2007, 1351 . 1353 [RFC6234] Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms 1354 (SHA and SHA-based HMAC and HKDF)", RFC 6234, 1355 DOI 10.17487/RFC6234, May 2011, 1356 . 1358 [RFC6831] Farinacci, D., Meyer, D., Zwiebel, J., and S. Venaas, "The 1359 Locator/ID Separation Protocol (LISP) for Multicast 1360 Environments", RFC 6831, DOI 10.17487/RFC6831, January 1361 2013, . 1363 [RFC6836] Fuller, V., Farinacci, D., Meyer, D., and D. Lewis, 1364 "Locator/ID Separation Protocol Alternative Logical 1365 Topology (LISP+ALT)", RFC 6836, DOI 10.17487/RFC6836, 1366 January 2013, . 1368 [RFC6837] Lear, E., "NERD: A Not-so-novel Endpoint ID (EID) to 1369 Routing Locator (RLOC) Database", RFC 6837, 1370 DOI 10.17487/RFC6837, January 2013, 1371 . 1373 [RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger, 1374 L., Sridhar, T., Bursell, M., and C. Wright, "Virtual 1375 eXtensible Local Area Network (VXLAN): A Framework for 1376 Overlaying Virtualized Layer 2 Networks over Layer 3 1377 Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014, 1378 . 1380 [RFC7835] Saucez, D., Iannone, L., and O. Bonaventure, "Locator/ID 1381 Separation Protocol (LISP) Threat Analysis", RFC 7835, 1382 DOI 10.17487/RFC7835, April 2016, 1383 . 1385 [RFC8060] Farinacci, D., Meyer, D., and J. Snijders, "LISP Canonical 1386 Address Format (LCAF)", RFC 8060, DOI 10.17487/RFC8060, 1387 February 2017, . 1389 7.2. Informative References 1391 [AFI] IANA, , "Address Family Identifier (AFIs)", ADDRESS FAMILY 1392 NUMBERS http://www.iana.org/assignments/address-family- 1393 numbers/address-family-numbers.xhtml?, Febuary 2007. 1395 [I-D.ermagan-lisp-nat-traversal] 1396 Ermagan, V., Farinacci, D., Lewis, D., Skriver, J., Maino, 1397 F., and C. White, "NAT traversal for LISP", draft-ermagan- 1398 lisp-nat-traversal-12 (work in progress), March 2017. 1400 [I-D.ietf-lisp-ddt] 1401 Fuller, V., Lewis, D., Ermagan, V., Jain, A., and A. 1402 Smirnov, "LISP Delegated Database Tree", draft-ietf-lisp- 1403 ddt-09 (work in progress), January 2017. 1405 [I-D.ietf-lisp-introduction] 1406 Cabellos-Aparicio, A. and D. Saucez, "An Architectural 1407 Introduction to the Locator/ID Separation Protocol 1408 (LISP)", draft-ietf-lisp-introduction-13 (work in 1409 progress), April 2015. 1411 [I-D.ietf-lisp-rfc6830bis] 1412 Farinacci, D., Fuller, V., Meyer, D., Lewis, D., and A. 1413 Cabellos-Aparicio, "The Locator/ID Separation Protocol 1414 (LISP)", draft-ietf-lisp-rfc6830bis-00 (work in progress), 1415 December 2016. 1417 [I-D.ietf-lisp-sec] 1418 Maino, F., Ermagan, V., Cabellos-Aparicio, A., and D. 1419 Saucez, "LISP-Security (LISP-SEC)", draft-ietf-lisp-sec-12 1420 (work in progress), November 2016. 1422 [I-D.ietf-lisp-signal-free-multicast] 1423 Moreno, V. and D. Farinacci, "Signal-Free LISP Multicast", 1424 draft-ietf-lisp-signal-free-multicast-02 (work in 1425 progress), October 2016. 1427 [I-D.lewis-lisp-gpe] 1428 Lewis, D., Agarwal, P., Kreeger, L., Maino, F., Quinn, P., 1429 Smith, M., and N. Yadav, "LISP Generic Protocol 1430 Extension", draft-lewis-lisp-gpe-02 (work in progress), 1431 July 2014. 1433 [I-D.meyer-lisp-mn] 1434 Farinacci, D., Lewis, D., Meyer, D., and C. White, "LISP 1435 Mobile Node", draft-meyer-lisp-mn-16 (work in progress), 1436 December 2016. 1438 [I-D.portoles-lisp-eid-mobility] 1439 Portoles-Comeras, M., Ashtaputre, V., Moreno, V., Maino, 1440 F., and D. Farinacci, "LISP L2/L3 EID Mobility Using a 1441 Unified Control Plane", draft-portoles-lisp-eid- 1442 mobility-01 (work in progress), October 2016. 1444 [I-D.quinn-vxlan-gpe] 1445 Quinn, P., Manur, R., Kreeger, L., Lewis, D., Maino, F., 1446 Smith, M., Agarwal, P., Yong, L., Xu, X., Elzur, U., Garg, 1447 P., and D. Melman, "Generic Protocol Extension for VXLAN", 1448 draft-quinn-vxlan-gpe-04 (work in progress), February 1449 2015. 1451 [LISP-CONS] 1452 Brim, S., Chiappa, N., Farinacci, D., Fuller, V., Lewis, 1453 D., and D. Meyer, "LISP-CONS: A Content distribution 1454 Overlay Network Service for LISP", Work in Progress, April 1455 2008. 1457 Appendix A. Acknowledgments 1459 The authors would like to thank Greg Schudel, Darrel Lewis, John 1460 Zwiebel, Andrew Partan, Dave Meyer, Isidor Kouvelas, Jesper Skriver, 1461 Fabio Maino, and members of the lisp@ietf.org mailing list for their 1462 feedback and helpful suggestions. 1464 Special thanks are due to Noel Chiappa for his extensive work on 1465 caching with LISP-CONS, some of which may be used by Map-Resolvers. 1467 Appendix B. Document Change Log 1469 [RFC Editor: Please delete this section on publication as RFC.] 1471 B.1. Changes to draft-ietf-lisp-rfc6833bis-01 1473 o Posted March 2017. 1475 o Include references to new RFCs published. 1477 o Remove references to self. 1479 o Change references from RFC6830 to RFC6830bis. 1481 o Add two new action/reasons to a Map-Reply has posted to the LISP 1482 WG mailing list. 1484 o In intro section, add refernece to I-D.ietf-lisp-introduction. 1486 o Removed Open Issues section and references to "experimental". 1488 B.2. Changes to draft-ietf-lisp-rfc6833bis-00 1490 o Posted December 2016. 1492 o Created working group document from draft-farinacci-lisp 1493 -rfc6833-00 individual submission. No other changes made. 1495 B.3. Changes to draft-farinacci-lisp-rfc6833bis-00 1497 o Posted November 2016. 1499 o This is the initial draft to turn RFC 6833 into RFC 6833bis. 1501 o The document name has changed from the "Locator/ID Separation 1502 Protocol (LISP) Map-Server Interface" to the "Locator/ID 1503 Separation Protocol (LISP) Control-Plane". 1505 o The fundamental change was to move the control-plane messages from 1506 RFC 6830 to this document in an effort so any IETF developed or 1507 industry created data-plane could use the LISP mapping system and 1508 control-plane. 1510 o Update control-plane messages to incorporate what has been 1511 implemented in products during the early phase of LISP development 1512 but wasn't able to make it into RFC6830 and RFC6833 to make the 1513 Experimental RFC deadline. 1515 o Indicate there may be nodes in the mapping system that are not MRs 1516 or MSs, that is a ALT-node or a DDT-node. 1518 o Include LISP-DDT in Map-Resolver section and explain how they 1519 maintain a referral-cache. 1521 o Removed open issue about additional state in Map-Servers. With 1522 [I-D.ietf-lisp-ddt], Map-Servers have the same registration state 1523 and can give Map-Resolvers complete information in ms-ack Map- 1524 Referral messages. 1526 o Make reference to the LISP Threats Analysis RFC [RFC7835]. 1528 Authors' Addresses 1530 Vince Fuller 1531 Cisco Systems 1533 EMail: vaf@vaf.net 1535 Dino Farinacci 1536 Cisco Systems 1538 EMail: farinacci@gmail.com 1540 Albert Cabellos 1541 UPC/BarcelonaTech 1542 Campus Nord, C. Jordi Girona 1-3 1543 Barcelona, Catalunya 1544 Spain 1546 EMail: acabello@ac.upc.edu