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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 303: '... Implementations MUST be prepared to a...' RFC 2119 keyword, line 312: '...ol messages. It MUST be checked on re...' RFC 2119 keyword, line 313: '... fails, the packet MUST be dropped....' RFC 2119 keyword, line 386: '...ch indicates that a Map-Request SHOULD...' RFC 2119 keyword, line 387: '...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 (April 11, 2017) is 2572 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: October 13, 2017 A. Cabellos (Ed.) 6 UPC/BarcelonaTech 7 April 11, 2017 9 Locator/ID Separation Protocol (LISP) Control-Plane 10 draft-ietf-lisp-rfc6833bis-02 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 October 13, 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-02 . . . . . . . . 36 89 B.2. Changes to draft-ietf-lisp-rfc6833bis-01 . . . . . . . . 36 90 B.3. Changes to draft-ietf-lisp-rfc6833bis-00 . . . . . . . . 36 91 B.4. Changes to draft-farinacci-lisp-rfc6833bis-00 . . . . . . 37 92 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 37 94 1. Introduction 96 The Locator/ID Separation Protocol [I-D.ietf-lisp-introduction] and 97 [I-D.ietf-lisp-rfc6830bis] specifies an architecture and mechanism 98 for replacing the addresses currently used by IP with two separate 99 name spaces: Endpoint IDs (EIDs), used within sites; and Routing 100 Locators (RLOCs), used on the transit networks that make up the 101 Internet infrastructure. To achieve this separation, LISP defines 102 protocol mechanisms for mapping from EIDs to RLOCs. In addition, 103 LISP assumes the existence of a database to store and propagate those 104 mappings globally. Several such databases have been proposed; among 105 them are the Content distribution Overlay Network Service for LISP 106 (LISP-CONS) [LISP-CONS], LISP-NERD (a Not-so-novel EID-to-RLOC 107 Database) [RFC6837], LISP Alternative Logical Topology (LISP+ALT) 108 [RFC6836], and LISP Delegated Database Tree (LISP-DDT) 109 [I-D.ietf-lisp-ddt]. 111 The LISP Mapping Service defines two new types of LISP-speaking 112 devices: the Map-Resolver, which accepts Map-Requests from an Ingress 113 Tunnel Router (ITR) and "resolves" the EID-to-RLOC mapping using a 114 mapping database; and the Map-Server, which learns authoritative EID- 115 to-RLOC mappings from an Egress Tunnel Router (ETR) and publishes 116 them in a database. 118 This LISP Control-Plane Mapping Service can be used by many different 119 encapsulation-based or translation-based data-planes which include 120 but are not limited to the ones defined in LISP RFC 6830bis 121 [I-D.ietf-lisp-rfc6830bis], LISP-GPE [I-D.lewis-lisp-gpe], VXLAN 122 [RFC7348], and VXLAN-GPE [I-D.quinn-vxlan-gpe]. 124 Conceptually, LISP Map-Servers share some of the same basic 125 configuration and maintenance properties as Domain Name System (DNS) 126 [RFC1035] servers; likewise, Map-Resolvers are conceptually similar 127 to DNS caching resolvers. With this in mind, this specification 128 borrows familiar terminology (resolver and server) from the DNS 129 specifications. 131 Note that while this document assumes a LISP+ALT database mapping 132 infrastructure to illustrate certain aspects of Map-Server and Map- 133 Resolver operation, the Mapping Service interface can (and likely 134 will) be used by ITRs and ETRs to access other mapping database 135 systems as the LISP infrastructure evolves. 137 The LISP Mapping Service is an important component of the LISP 138 toolset. Issues and concerns about the deployment of LISP for 139 Internet traffic are discussed in [I-D.ietf-lisp-rfc6830bis]. 141 2. Definition of Terms 143 Map-Server: A network infrastructure component that learns of EID- 144 Prefix mapping entries from an ETR, via the registration mechanism 145 described below, or some other authoritative source if one exists. 146 A Map-Server publishes these EID-Prefixes in a mapping database. 148 Map-Resolver: A network infrastructure component that accepts LISP 149 Encapsulated Map-Requests, typically from an ITR, and determines 150 whether or not the destination IP address is part of the EID 151 namespace; if it is not, a Negative Map-Reply is returned. 152 Otherwise, the Map-Resolver finds the appropriate EID-to-RLOC 153 mapping by consulting a mapping database system. 155 Encapsulated Map-Request: A LISP Map-Request carried within an 156 Encapsulated Control Message, which has an additional LISP header 157 prepended. Sent to UDP destination port 4342. The "outer" 158 addresses are globally routable IP addresses, also known as RLOCs. 159 Used by an ITR when sending to a Map-Resolver and by a Map-Server 160 when forwarding a Map-Request to an ETR. 162 Negative Map-Reply: A LISP Map-Reply that contains an empty 163 Locator-Set. Returned in response to a Map-Request if the 164 destination EID does not exist in the mapping database. 165 Typically, this means that the "EID" being requested is an IP 166 address connected to a non-LISP site. 168 Map-Register message: A LISP message sent by an ETR to a Map-Server 169 to register its associated EID-Prefixes. In addition to the set 170 of EID-Prefixes to register, the message includes one or more 171 RLOCs to be used by the Map-Server when forwarding Map-Requests 172 (re-formatted as Encapsulated Map-Requests) received through the 173 database mapping system. An ETR may request that the Map-Server 174 answer Map-Requests on its behalf by setting the "proxy Map-Reply" 175 flag (P-bit) in the message. 177 Map-Notify message: A LISP message sent by a Map-Server to an ETR 178 to confirm that a Map-Register has been received and processed. 179 An ETR requests that a Map-Notify be returned by setting the 180 "want-map-notify" flag (M-bit) in the Map-Register message. 181 Unlike a Map-Reply, a Map-Notify uses UDP port 4342 for both 182 source and destination. 184 For definitions of other terms -- notably Map-Request, Map-Reply, 185 Ingress Tunnel Router (ITR), and Egress Tunnel Router (ETR) -- please 186 consult the LISP specification [I-D.ietf-lisp-rfc6830bis]. 188 3. Basic Overview 190 A Map-Server is a device that publishes EID-Prefixes in a LISP 191 mapping database on behalf of a set of ETRs. When it receives a Map 192 Request (typically from an ITR), it consults the mapping database to 193 find an ETR that can answer with the set of RLOCs for an EID-Prefix. 194 To publish its EID-Prefixes, an ETR periodically sends Map-Register 195 messages to the Map-Server. A Map-Register message contains a list 196 of EID-Prefixes plus a set of RLOCs that can be used to reach the ETR 197 when a Map-Server needs to forward a Map-Request to it. 199 When LISP+ALT is used as the mapping database, a Map-Server connects 200 to the ALT network and acts as a "last-hop" ALT-Router. Intermediate 201 ALT-Routers forward Map-Requests to the Map-Server that advertises a 202 particular EID-Prefix, and the Map-Server forwards them to the owning 203 ETR, which responds with Map-Reply messages. 205 When LISP-DDT [I-D.ietf-lisp-ddt] is used as the mapping database, a 206 Map-Server sends the final Map-Referral messages from the Delegated 207 Database Tree. 209 A Map-Resolver receives Encapsulated Map-Requests from its client 210 ITRs and uses a mapping database system to find the appropriate ETR 211 to answer those requests. On a LISP+ALT network, a Map-Resolver acts 212 as a "first-hop" ALT-Router. It has Generic Routing Encapsulation 213 (GRE) tunnels configured to other ALT-Routers and uses BGP to learn 214 paths to ETRs for different prefixes in the LISP+ALT database. The 215 Map-Resolver uses this path information to forward Map-Requests over 216 the ALT to the correct ETRs. On a LISP-DDT network 217 [I-D.ietf-lisp-ddt], a Map-Resolver maintains a referral-cache and 218 acts as a "first-hop" DDT-node. The Map-Resolver uses the referral 219 information to forward Map-Requests. 221 Note that while it is conceivable that a non-LISP-DDT Map-Resolver 222 could cache responses to improve performance, issues surrounding 223 cache management will need to be resolved so that doing so will be 224 reliable and practical. As initially deployed, Map-Resolvers will 225 operate only in a non-caching mode, decapsulating and forwarding 226 Encapsulated Map Requests received from ITRs. Any specification of 227 caching functionality is left for future work. 229 Note that a single device can implement the functions of both a Map- 230 Server and a Map-Resolver, and in many cases the functions will be 231 co-located in that way. Also, there can be ALT-only nodes and DDT- 232 only nodes, when LISP+ALT and LISP-DDT are used, respectively, to 233 connect Map-Resolvers and Map-Servers together to make up the Mapping 234 System. 236 Detailed descriptions of the LISP packet types referenced by this 237 document may be found in [I-D.ietf-lisp-rfc6830bis]. 239 4. LISP IPv4 and IPv6 Control-Plane Packet Formats 241 The following UDP packet formats are used by the LISP control plane. 243 0 1 2 3 244 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 1 245 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 246 |Version| IHL |Type of Service| Total Length | 247 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 248 | Identification |Flags| Fragment Offset | 249 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 250 | Time to Live | Protocol = 17 | Header Checksum | 251 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 252 | Source Routing Locator | 253 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 254 | Destination Routing Locator | 255 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 256 / | Source Port | Dest Port | 257 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 258 \ | UDP Length | UDP Checksum | 259 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 260 | | 261 | LISP Message | 262 | | 263 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 265 0 1 2 3 266 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 1 267 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 268 |Version| Traffic Class | Flow Label | 269 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 270 | Payload Length | Next Header=17| Hop Limit | 271 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 272 | | 273 + + 274 | | 275 + Source Routing Locator + 276 | | 277 + + 278 | | 279 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 280 | | 281 + + 282 | | 283 + Destination Routing Locator + 284 | | 285 + + 286 | | 287 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 288 / | Source Port | Dest Port | 289 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 290 \ | UDP Length | UDP Checksum | 291 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 292 | | 293 | LISP Message | 294 | | 295 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 297 The LISP UDP-based messages are the Map-Request and Map-Reply 298 messages. When a UDP Map-Request is sent, the UDP source port is 299 chosen by the sender and the destination UDP port number is set to 300 4342. When a UDP Map-Reply is sent, the source UDP port number is 301 set to 4342 and the destination UDP port number is copied from the 302 source port of either the Map-Request or the invoking data packet. 303 Implementations MUST be prepared to accept packets when either the 304 source port or destination UDP port is set to 4342 due to NATs 305 changing port number values. 307 The 'UDP Length' field will reflect the length of the UDP header and 308 the LISP Message payload. 310 The UDP checksum is computed and set to non-zero for Map-Request, 311 Map-Reply, Map-Register, and Encapsulated Control Message (ECM) 312 control messages. It MUST be checked on receipt, and if the checksum 313 fails, the packet MUST be dropped. 315 The format of control messages includes the UDP header so the 316 checksum and length fields can be used to protect and delimit message 317 boundaries. 319 4.1. LISP Control Packet Type Allocations 321 This section will be the authoritative source for allocating LISP 322 Type values and for defining LISP control message formats. Current 323 allocations are: 325 Reserved: 0 b'0000' 326 LISP Map-Request: 1 b'0001' 327 LISP Map-Reply: 2 b'0010' 328 LISP Map-Register: 3 b'0011' 329 LISP Map-Notify: 4 b'0100' 330 LISP Map-Notify-Ack: 5 b'0101' 331 LISP Map-Referral: 6 b'0110' 332 LISP Info-Request/Reply: 7 b'0111' 333 LISP Encapsulated Control Message: 8 b'1000' 335 All LISP control-plane messages use Address Family Identifiers (AFI) 336 [AFI] or LISP Canonical Address Format (LCAF) [RFC8060] formats to 337 encode either fixed or variable length addresses. This includes 338 explicit fields in each control message or part of EID-records or 339 RLOC-records in commonly formatted messages. 341 The LISP control-plane describes how other data-planes can encode 342 messages to support the SMR and RLOC-probing procedures of the LISP 343 data-plane defined in [I-D.ietf-lisp-rfc6830bis]. This control-plane 344 specification itself does not offer such functionality and other 345 data-planes can use their own mechanisms that do not rely on the LISP 346 control-plane. 348 4.2. Map-Request Message Format 350 0 1 2 3 351 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 1 352 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 353 |Type=1 |A|M|P|S|p|s|m| Reserved |L|D| IRC | Record Count | 354 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 355 | Nonce . . . | 356 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 357 | . . . Nonce | 358 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 359 | Source-EID-AFI | Source EID Address ... | 360 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 361 | ITR-RLOC-AFI 1 | ITR-RLOC Address 1 ... | 362 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 363 | ... | 364 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 365 | ITR-RLOC-AFI n | ITR-RLOC Address n ... | 366 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 367 / | Reserved | EID mask-len | EID-Prefix-AFI | 368 Rec +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 369 \ | EID-Prefix ... | 370 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 371 | Map-Reply Record ... | 372 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 374 Packet field descriptions: 376 Type: 1 (Map-Request) 378 A: This is an authoritative bit, which is set to 0 for UDP-based Map- 379 Requests sent by an ITR. It is set to 1 when an ITR wants the 380 destination site to return the Map-Reply rather than the mapping 381 database system. 383 M: This is the map-data-present bit. When set, it indicates that a 384 Map-Reply Record segment is included in the Map-Request. 386 P: This is the probe-bit, which indicates that a Map-Request SHOULD 387 be treated as a Locator reachability probe. The receiver SHOULD 388 respond with a Map-Reply with the probe-bit set, indicating that 389 the Map-Reply is a Locator reachability probe reply, with the 390 nonce copied from the Map-Request. See RLOC-Probing 391 [I-D.ietf-lisp-rfc6830bis] for more details. 393 S: This is the Solicit-Map-Request (SMR) bit. See Solicit-Map- 394 Request (SMRs) [I-D.ietf-lisp-rfc6830bis] for details. 396 p: This is the PITR bit. This bit is set to 1 when a PITR sends a 397 Map-Request. 399 s: This is the SMR-invoked bit. This bit is set to 1 when an xTR is 400 sending a Map-Request in response to a received SMR-based Map- 401 Request. 403 m: This is the LISP mobile-node m-bit. This bit is set by xTRs that 404 operate as a mobile node as defined in [I-D.meyer-lisp-mn]. 406 Reserved: This field MUST be set to 0 on transmit and MUST be 407 ignored on receipt. 409 L: This is the local-xtr bit. It is used by an xTR in a LISP site to 410 tell other xTRs in the same site that it is local to the site. 411 That is, that it is part of the RLOC-set for the LISP site. 413 D: This is the dont-map-reply bit. It is used in the SMR procedure 414 described in [I-D.ietf-lisp-rfc6830bis]. When an xTR sends an SMR 415 Map-Request message, it doesn't need a Map-Reply returned. When 416 this bit is set, the receiver of the Map-Request does not return a 417 Map-Reply. 419 IRC: This 5-bit field is the ITR-RLOC Count, which encodes the 420 additional number of ('ITR-RLOC-AFI', 'ITR-RLOC Address') fields 421 present in this message. At least one (ITR-RLOC-AFI, ITR-RLOC- 422 Address) pair MUST be encoded. Multiple 'ITR-RLOC Address' fields 423 are used, so a Map-Replier can select which destination address to 424 use for a Map-Reply. The IRC value ranges from 0 to 31. For a 425 value of 0, there is 1 ITR-RLOC address encoded; for a value of 1, 426 there are 2 ITR-RLOC addresses encoded, and so on up to 31, which 427 encodes a total of 32 ITR-RLOC addresses. 429 Record Count: This is the number of records in this Map-Request 430 message. A record is comprised of the portion of the packet that 431 is labeled 'Rec' above and occurs the number of times equal to 432 Record Count. For this version of the protocol, a receiver MUST 433 accept and process Map-Requests that contain one or more records, 434 but a sender MUST only send Map-Requests containing one record. 435 Support for requesting multiple EIDs in a single Map-Request 436 message will be specified in a future version of the protocol. 438 Nonce: This is an 8-octet random value created by the sender of the 439 Map-Request. This nonce will be returned in the Map-Reply. The 440 security of the LISP mapping protocol critically depends on the 441 strength of the nonce in the Map-Request message. The nonce 442 SHOULD be generated by a properly seeded pseudo-random (or strong 443 random) source. See [RFC4086] for advice on generating security- 444 sensitive random data. 446 Source-EID-AFI: This is the address family of the 'Source EID 447 Address' field. 449 Source EID Address: This is the EID of the source host that 450 originated the packet that caused the Map-Request. When Map- 451 Requests are used for refreshing a Map-Cache entry or for RLOC- 452 Probing, an AFI value 0 is used and this field is of zero length. 454 ITR-RLOC-AFI: This is the address family of the 'ITR-RLOC Address' 455 field that follows this field. 457 ITR-RLOC Address: This is used to give the ETR the option of 458 selecting the destination address from any address family for the 459 Map-Reply message. This address MUST be a routable RLOC address 460 of the sender of the Map-Request message. 462 EID mask-len: This is the mask length for the EID-Prefix. 464 EID-Prefix-AFI: This is the address family of the EID-Prefix 465 according to [AFI] and [RFC8060]. 467 EID-Prefix: This prefix is 4 octets for an IPv4 address family and 468 16 octets for an IPv6 address family. When a Map-Request is sent 469 by an ITR because a data packet is received for a destination 470 where there is no mapping entry, the EID-Prefix is set to the 471 destination IP address of the data packet, and the 'EID mask-len' 472 is set to 32 or 128 for IPv4 or IPv6, respectively. When an xTR 473 wants to query a site about the status of a mapping it already has 474 cached, the EID-Prefix used in the Map-Request has the same mask 475 length as the EID-Prefix returned from the site when it sent a 476 Map-Reply message. 478 Map-Reply Record: When the M-bit is set, this field is the size of a 479 single "Record" in the Map-Reply format. This Map-Reply record 480 contains the EID-to-RLOC mapping entry associated with the Source 481 EID. This allows the ETR that will receive this Map-Request to 482 cache the data if it chooses to do so. 484 4.3. EID-to-RLOC UDP Map-Request Message 486 A Map-Request is sent from an ITR when it needs a mapping for an EID, 487 wants to test an RLOC for reachability, or wants to refresh a mapping 488 before TTL expiration. For the initial case, the destination IP 489 address used for the Map-Request is the data packet's destination 490 address (i.e., the destination EID) that had a mapping cache lookup 491 failure. For the latter two cases, the destination IP address used 492 for the Map-Request is one of the RLOC addresses from the Locator-Set 493 of the Map-Cache entry. The source address is either an IPv4 or IPv6 494 RLOC address, depending on whether the Map-Request is using an IPv4 495 or IPv6 header, respectively. In all cases, the UDP source port 496 number for the Map-Request message is a 16-bit value selected by the 497 ITR/PITR, and the UDP destination port number is set to the well- 498 known destination port number 4342. A successful Map-Reply, which is 499 one that has a nonce that matches an outstanding Map-Request nonce, 500 will update the cached set of RLOCs associated with the EID-Prefix 501 range. 503 One or more Map-Request ('ITR-RLOC-AFI', 'ITR-RLOC-Address') fields 504 MUST be filled in by the ITR. The number of fields (minus 1) encoded 505 MUST be placed in the 'IRC' field. The ITR MAY include all locally 506 configured Locators in this list or just provide one locator address 507 from each address family it supports. If the ITR erroneously 508 provides no ITR-RLOC addresses, the Map-Replier MUST drop the Map- 509 Request. 511 Map-Requests can also be LISP encapsulated using UDP destination 512 port 4342 with a LISP Type value set to "Encapsulated Control 513 Message", when sent from an ITR to a Map-Resolver. Likewise, Map- 514 Requests are LISP encapsulated the same way from a Map-Server to an 515 ETR. Details on Encapsulated Map-Requests and Map-Resolvers can be 516 found in Section 4.8. 518 Map-Requests MUST be rate-limited. It is RECOMMENDED that a Map- 519 Request for the same EID-Prefix be sent no more than once per second. 521 An ITR that is configured with mapping database information (i.e., it 522 is also an ETR) MAY optionally include those mappings in a Map- 523 Request. When an ETR configured to accept and verify such 524 "piggybacked" mapping data receives such a Map-Request and it does 525 not have this mapping in the map-cache, it MAY originate a "verifying 526 Map-Request", addressed to the map-requesting ITR and the ETR MAY add 527 a Map-Cache entry. If the ETR has a Map-Cache entry that matches the 528 "piggybacked" EID and the RLOC is in the Locator-Set for the entry, 529 then it may send the "verifying Map-Request" directly to the 530 originating Map-Request source. If the RLOC is not in the Locator- 531 Set, then the ETR MUST send the "verifying Map-Request" to the 532 "piggybacked" EID. Doing this forces the "verifying Map-Request" to 533 go through the mapping database system to reach the authoritative 534 source of information about that EID, guarding against RLOC-spoofing 535 in the "piggybacked" mapping data. 537 4.4. Map-Reply Message Format 539 0 1 2 3 540 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 1 541 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 542 |Type=2 |P|E|S| Reserved | Record Count | 543 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 544 | Nonce . . . | 545 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 546 | . . . Nonce | 547 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 548 | | Record TTL | 549 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 550 R | Locator Count | EID mask-len | ACT |A| Reserved | 551 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 552 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 553 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 554 r | EID-Prefix | 555 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 556 | /| Priority | Weight | M Priority | M Weight | 557 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 558 | o | Unused Flags |L|p|R| Loc-AFI | 559 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 560 | \| Locator | 561 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 563 Packet field descriptions: 565 Type: 2 (Map-Reply) 567 P: This is the probe-bit, which indicates that the Map-Reply is in 568 response to a Locator reachability probe Map-Request. The 'Nonce' 569 field MUST contain a copy of the nonce value from the original 570 Map-Request. See RLOC-probing [I-D.ietf-lisp-rfc6830bis] for more 571 details. 573 E: This bit indicates that the ETR that sends this Map-Reply message 574 is advertising that the site is enabled for the Echo-Nonce Locator 575 reachability algorithm. See Echo-Nonce [I-D.ietf-lisp-rfc6830bis] 576 for more details. 578 S: This is the Security bit. When set to 1, the following 579 authentication information will be appended to the end of the Map- 580 Reply. The details of signing a Map-Reply message can be found in 581 [I-D.ietf-lisp-sec]. 583 0 1 2 3 584 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 1 585 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 586 | AD Type | Authentication Data Content . . . | 587 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 589 Reserved: This field MUST be set to 0 on transmit and MUST be 590 ignored on receipt. 592 Record Count: This is the number of records in this reply message. 593 A record is comprised of that portion of the packet labeled 594 'Record' above and occurs the number of times equal to Record 595 Count. 597 Nonce: This is a 24-bit value set in a Data-Probe packet, or a 598 64-bit value from the Map-Request is echoed in this 'Nonce' field 599 of the Map-Reply. When a 24-bit value is supplied, it resides in 600 the low-order 64 bits of the 'Nonce' field. 602 Record TTL: This is the time in minutes the recipient of the Map- 603 Reply will store the mapping. If the TTL is 0, the entry SHOULD 604 be removed from the cache immediately. If the value is 605 0xffffffff, the recipient can decide locally how long to store the 606 mapping. 608 Locator Count: This is the number of Locator entries. A Locator 609 entry comprises what is labeled above as 'Loc'. The Locator count 610 can be 0, indicating that there are no Locators for the EID- 611 Prefix. 613 EID mask-len: This is the mask length for the EID-Prefix. 615 ACT: This 3-bit field describes Negative Map-Reply actions. In any 616 other message type, these bits are set to 0 and ignored on 617 receipt. These bits are used only when the 'Locator Count' field 618 is set to 0. The action bits are encoded only in Map-Reply 619 messages. The actions defined are used by an ITR or PITR when a 620 destination EID matches a negative Map-Cache entry. Unassigned 621 values should cause a Map-Cache entry to be created, and when 622 packets match this negative cache entry, they will be dropped. 623 The current assigned values are: 625 (0) No-Action: The map-cache is kept alive, and no packet 626 encapsulation occurs. 628 (1) Natively-Forward: The packet is not encapsulated or dropped 629 but natively forwarded. 631 (2) Send-Map-Request: The packet invokes sending a Map-Request. 633 (3) Drop/No-Reason: A packet that matches this map-cache entry is 634 dropped. An ICMP Destination Unreachable message SHOULD be 635 sent. 637 (4) Drop/Policy-Denied: A packet that matches this map-cache 638 entry is dropped. The reason for the Drop action is that a 639 Map-Request for the target-EID is being policy denied by 640 either an xTR or the mapping system. 642 (5) Drop/Authentication-Failure: A packet that matches this map- 643 cache entry is dropped. The reason for the Drop action is 644 that a Map-Request for the target-EID fails an authentication 645 verification-check by either an xTR or the mapping system. 647 A: The Authoritative bit, when sent, is always set to 1 by an ETR. 648 When a Map-Server is proxy Map-Replying for a LISP site, the 649 Authoritative bit is set to 0. This indicates to requesting ITRs 650 that the Map-Reply was not originated by a LISP node managed at 651 the site that owns the EID-Prefix. 653 Map-Version Number: When this 12-bit value is non-zero, the Map- 654 Reply sender is informing the ITR what the version number is for 655 the EID record contained in the Map-Reply. The ETR can allocate 656 this number internally but MUST coordinate this value with other 657 ETRs for the site. When this value is 0, there is no versioning 658 information conveyed. The Map-Version Number can be included in 659 Map-Request and Map-Register messages. See Map-Versioning 660 [I-D.ietf-lisp-rfc6830bis] for more details. 662 EID-Prefix-AFI: Address family of the EID-Prefix according to [AFI] 663 and [RFC8060]. 665 EID-Prefix: This prefix is 4 octets for an IPv4 address family and 666 16 octets for an IPv6 address family. 668 Priority: Each RLOC is assigned a unicast Priority. Lower values 669 are more preferable. When multiple RLOCs have the same Priority, 670 they MAY be used in a load-split fashion. A value of 255 means 671 the RLOC MUST NOT be used for unicast forwarding. 673 Weight: When priorities are the same for multiple RLOCs, the Weight 674 indicates how to balance unicast traffic between them. Weight is 675 encoded as a relative weight of total unicast packets that match 676 the mapping entry. For example, if there are 4 Locators in a 677 Locator-Set, where the Weights assigned are 30, 20, 20, and 10, 678 the first Locator will get 37.5% of the traffic, the 2nd and 3rd 679 Locators will get 25% of the traffic, and the 4th Locator will get 680 12.5% of the traffic. If all Weights for a Locator-Set are equal, 681 the receiver of the Map-Reply will decide how to load-split the 682 traffic. See RLOC-hashing [I-D.ietf-lisp-rfc6830bis] for a 683 suggested hash algorithm to distribute the load across Locators 684 with the same Priority and equal Weight values. 686 M Priority: Each RLOC is assigned a multicast Priority used by an 687 ETR in a receiver multicast site to select an ITR in a source 688 multicast site for building multicast distribution trees. A value 689 of 255 means the RLOC MUST NOT be used for joining a multicast 690 distribution tree. For more details, see [RFC6831]. 692 M Weight: When priorities are the same for multiple RLOCs, the 693 Weight indicates how to balance building multicast distribution 694 trees across multiple ITRs. The Weight is encoded as a relative 695 weight (similar to the unicast Weights) of the total number of 696 trees built to the source site identified by the EID-Prefix. If 697 all Weights for a Locator-Set are equal, the receiver of the Map- 698 Reply will decide how to distribute multicast state across ITRs. 699 For more details, see [RFC6831]. 701 Unused Flags: These are set to 0 when sending and ignored on 702 receipt. 704 L: When this bit is set, the Locator is flagged as a local Locator to 705 the ETR that is sending the Map-Reply. When a Map-Server is doing 706 proxy Map-Replying for a LISP site, the L-bit is set to 0 for all 707 Locators in this Locator-Set. 709 p: When this bit is set, an ETR informs the RLOC-Probing ITR that the 710 locator address for which this bit is set is the one being RLOC- 711 probed and MAY be different from the source address of the Map- 712 Reply. An ITR that RLOC-probes a particular Locator MUST use this 713 Locator for retrieving the data structure used to store the fact 714 that the Locator is reachable. The p-bit is set for a single 715 Locator in the same Locator-Set. If an implementation sets more 716 than one p-bit erroneously, the receiver of the Map-Reply MUST 717 select the first Locator. The p-bit MUST NOT be set for Locator- 718 Set records sent in Map-Request and Map-Register messages. 720 R: This is set when the sender of a Map-Reply has a route to the 721 Locator in the Locator data record. This receiver may find this 722 useful to know if the Locator is up but not necessarily reachable 723 from the receiver's point of view. See also EID-Reachability 724 [I-D.ietf-lisp-rfc6830bis] for another way the R-bit may be used. 726 Locator: This is an IPv4 or IPv6 address (as encoded by the 'Loc- 727 AFI' field) assigned to an ETR. Note that the destination RLOC 728 address MAY be an anycast address. A source RLOC can be an 729 anycast address as well. The source or destination RLOC MUST NOT 730 be the broadcast address (255.255.255.255 or any subnet broadcast 731 address known to the router) and MUST NOT be a link-local 732 multicast address. The source RLOC MUST NOT be a multicast 733 address. The destination RLOC SHOULD be a multicast address if it 734 is being mapped from a multicast destination EID. 736 4.5. EID-to-RLOC UDP Map-Reply Message 738 A Map-Reply returns an EID-Prefix with a prefix length that is less 739 than or equal to the EID being requested. The EID being requested is 740 either from the destination field of an IP header of a Data-Probe or 741 the EID record of a Map-Request. The RLOCs in the Map-Reply are 742 globally routable IP addresses of all ETRs for the LISP site. Each 743 RLOC conveys status reachability but does not convey path 744 reachability from a requester's perspective. Separate testing of 745 path reachability is required. See RLOC-reachability 746 [I-D.ietf-lisp-rfc6830bis] for details. 748 Note that a Map-Reply may contain different EID-Prefix granularity 749 (prefix + length) than the Map-Request that triggers it. This might 750 occur if a Map-Request were for a prefix that had been returned by an 751 earlier Map-Reply. In such a case, the requester updates its cache 752 with the new prefix information and granularity. For example, a 753 requester with two cached EID-Prefixes that are covered by a Map- 754 Reply containing one less-specific prefix replaces the entry with the 755 less-specific EID-Prefix. Note that the reverse, replacement of one 756 less-specific prefix with multiple more-specific prefixes, can also 757 occur, not by removing the less-specific prefix but rather by adding 758 the more-specific prefixes that, during a lookup, will override the 759 less-specific prefix. 761 When an ETR is configured with overlapping EID-Prefixes, a Map- 762 Request with an EID that best matches any EID-Prefix MUST be returned 763 in a single Map-Reply message. For instance, if an ETR had database 764 mapping entries for EID-Prefixes: 766 10.0.0.0/8 767 10.1.0.0/16 768 10.1.1.0/24 769 10.1.2.0/24 771 A Map-Request for EID 10.1.1.1 would cause a Map-Reply with a record 772 count of 1 to be returned with a mapping record EID-Prefix of 773 10.1.1.0/24. 775 A Map-Request for EID 10.1.5.5 would cause a Map-Reply with a record 776 count of 3 to be returned with mapping records for EID-Prefixes 777 10.1.0.0/16, 10.1.1.0/24, and 10.1.2.0/24. 779 Note that not all overlapping EID-Prefixes need to be returned but 780 only the more-specific entries (note that in the second example above 781 10.0.0.0/8 was not returned for requesting EID 10.1.5.5) for the 782 matching EID-Prefix of the requesting EID. When more than one EID- 783 Prefix is returned, all SHOULD use the same Time to Live value so 784 they can all time out at the same time. When a more-specific EID- 785 Prefix is received later, its Time to Live value in the Map-Reply 786 record can be stored even when other less-specific entries exist. 787 When a less-specific EID-Prefix is received later, its map-cache 788 expiration time SHOULD be set to the minimum expiration time of any 789 more-specific EID-Prefix in the map-cache. This is done so the 790 integrity of the EID-Prefix set is wholly maintained and so no more- 791 specific entries are removed from the map-cache while keeping less- 792 specific entries. 794 Map-Replies SHOULD be sent for an EID-Prefix no more often than once 795 per second to the same requesting router. For scalability, it is 796 expected that aggregation of EID addresses into EID-Prefixes will 797 allow one Map-Reply to satisfy a mapping for the EID addresses in the 798 prefix range, thereby reducing the number of Map-Request messages. 800 Map-Reply records can have an empty Locator-Set. A Negative Map- 801 Reply is a Map-Reply with an empty Locator-Set. Negative Map-Replies 802 convey special actions by the sender to the ITR or PITR that have 803 solicited the Map-Reply. There are two primary applications for 804 Negative Map-Replies. The first is for a Map-Resolver to instruct an 805 ITR or PITR when a destination is for a LISP site versus a non-LISP 806 site, and the other is to source quench Map-Requests that are sent 807 for non-allocated EIDs. 809 For each Map-Reply record, the list of Locators in a Locator-Set MUST 810 appear in the same order for each ETR that originates a Map-Reply 811 message. The Locator-Set MUST be sorted in order of ascending IP 812 address where an IPv4 locator address is considered numerically 'less 813 than' an IPv6 locator address. 815 When sending a Map-Reply message, the destination address is copied 816 from one of the 'ITR-RLOC' fields from the Map-Request. The ETR can 817 choose a locator address from one of the address families it 818 supports. For Data-Probes, the destination address of the Map-Reply 819 is copied from the source address of the Data-Probe message that is 820 invoking the reply. The source address of the Map-Reply is one of 821 the local IP addresses chosen to allow Unicast Reverse Path 822 Forwarding (uRPF) checks to succeed in the upstream service provider. 824 The destination port of a Map-Reply message is copied from the source 825 port of the Map-Request or Data-Probe, and the source port of the 826 Map-Reply message is set to the well-known UDP port 4342. 828 4.6. Map-Register Message Format 830 This section specifies the encoding format for the Map-Register 831 message. The message is sent in UDP with a destination UDP port of 832 4342 and a randomly selected UDP source port number. 834 The Map-Register message format is: 836 0 1 2 3 837 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 1 838 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 839 |Type=3 |P|S|I| Reserved |E|T|a|m|M| Record Count | 840 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 841 | Nonce . . . | 842 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 843 | . . . Nonce | 844 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 845 | Key ID | Authentication Data Length | 846 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 847 ~ Authentication Data ~ 848 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 849 | | Record TTL | 850 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 851 R | Locator Count | EID mask-len | ACT |A| Reserved | 852 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 853 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 854 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 855 r | EID-Prefix | 856 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 857 | /| Priority | Weight | M Priority | M Weight | 858 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 859 | o | Unused Flags |L|p|R| Loc-AFI | 860 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 861 | \| Locator | 862 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 864 Packet field descriptions: 866 Type: 3 (Map-Register) 868 P: This is the proxy Map-Reply bit. When set to 1, an ETR sends a 869 Map-Register message requesting the Map-Server to proxy a Map- 870 Reply. The Map-Server will send non-authoritative Map-Replies on 871 behalf of the ETR. 873 S: This is the security-capable bit. When set, the procedures from 874 [I-D.ietf-lisp-sec] are supported. 876 I: This is the xTR-ID bit. When this bit is set, what is appended to 877 the Map-Register is a 128-bit xTR router-ID and then a 64-bit 878 site-ID. See LISP NAT-Traversal procedures in 879 [I-D.ermagan-lisp-nat-traversal] for details. 881 Reserved: This field MUST be set to 0 on transmit and MUST be 882 ignored on receipt. 884 E: This is the Map-Register EID-notify bit. This is used by a First- 885 Hop-Router (FHR) which discovers a dynamic-EID. This EID-notify 886 based Map-Register is sent by the FHR to the same site xTR that 887 propogates the Map-Register to the mapping system. The site xTR 888 keeps state to later Map-Notify the FHR after the EID has moves 889 away. See [I-D.portoles-lisp-eid-mobility] for a detailed use- 890 case. 892 T: This is the use-TTL for timeout bit. When set to 1, the xTR wants 893 the Map-Server to time out registrations based on the value in the 894 "Record TTL" field of this message. 896 a: This is the merge-request bit. When set to 1, the xTR requests to 897 merge RLOC-records from different xTRs registering the same EID- 898 record. See signal-free multicast 899 [I-D.ietf-lisp-signal-free-multicast] for one use case example. 901 m: This is the mobile-node bit. When set to 1, the registering xTR 902 supports the procuedures in [I-D.meyer-lisp-mn]. 904 M: This is the want-map-notify bit. When set to 1, an ETR is 905 requesting a Map-Notify message to be returned in response to 906 sending a Map-Register message. The Map-Notify message sent by a 907 Map-Server is used to acknowledge receipt of a Map-Register 908 message. 910 Record Count: This is the number of records in this Map-Register 911 message. A record is comprised of that portion of the packet 912 labeled 'Record' above and occurs the number of times equal to 913 Record Count. 915 Nonce: This 8-octet 'Nonce' field is set to 0 in Map-Register 916 messages. Since the Map-Register message is authenticated, the 917 'Nonce' field is not currently used for any security function but 918 may be in the future as part of an anti-replay solution. 920 Key ID: This is a configured ID to find the configured Message 921 Authentication Code (MAC) algorithm and key value used for the 922 authentication function. See Key ID Numbers in 923 [I-D.ietf-lisp-rfc6830bis] for codepoint assignments. 925 Authentication Data Length: This is the length in octets of the 926 'Authentication Data' field that follows this field. The length 927 of the 'Authentication Data' field is dependent on the MAC 928 algorithm used. The length field allows a device that doesn't 929 know the MAC algorithm to correctly parse the packet. 931 Authentication Data: This is the message digest used from the output 932 of the MAC algorithm. The entire Map-Register payload is 933 authenticated with this field preset to 0. After the MAC is 934 computed, it is placed in this field. Implementations of this 935 specification MUST include support for HMAC-SHA-1-96 [RFC2404], 936 and support for HMAC-SHA-256-128 [RFC4868] is RECOMMENDED. 938 The definition of the rest of the Map-Register can be found in 939 Section 4.4. 941 4.7. Map-Notify/Map-Notify-Ack Message Format 943 This section specifies the encoding format for the Map-Notify and 944 Map-Notify-Ack messages. The messages are sent inside a UDP packet 945 with source and destination UDP ports equal to 4342. 947 The Map-Notify and Map-Notify-Ack message formats are: 949 0 1 2 3 950 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 1 951 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 952 |Type=4/5| Reserved | Record Count | 953 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 954 | Nonce . . . | 955 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 956 | . . . Nonce | 957 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 958 | Key ID | Authentication Data Length | 959 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 960 ~ Authentication Data ~ 961 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 962 | | Record TTL | 963 | +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 964 R | Locator Count | EID mask-len | ACT |A| Reserved | 965 e +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 966 c | Rsvd | Map-Version Number | EID-Prefix-AFI | 967 o +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 968 r | EID-Prefix | 969 d +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 970 | /| Priority | Weight | M Priority | M Weight | 971 | L +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 972 | o | Unused Flags |L|p|R| Loc-AFI | 973 | c +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 974 | \| Locator | 975 +-> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 977 Packet field descriptions: 979 Type: 4/5 (Map-Notify/Map-Notify-Ack) 981 The Map-Notify message has the same contents as a Map-Register 982 message. See the Map-Register section for field descriptions. 984 The Map-Notify-Ack message has the same contents as a Map-Notify 985 message. It is used to acknowledge the receipt of a Map-Notify and 986 for the sender to stop retransmitting a Map-Notify with the same 987 nonce. 989 4.8. Encapsulated Control Message Format 991 An Encapsulated Control Message (ECM) is used to encapsulate control 992 packets sent between xTRs and the mapping database system. 994 0 1 2 3 995 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 1 996 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 997 / | IPv4 or IPv6 Header | 998 OH | (uses RLOC addresses) | 999 \ | | 1000 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1001 / | Source Port = xxxx | Dest Port = 4342 | 1002 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1003 \ | UDP Length | UDP Checksum | 1004 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1005 LH |Type=8 |S|D|E|M| Reserved | 1006 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1007 / | IPv4 or IPv6 Header | 1008 IH | (uses RLOC or EID addresses) | 1009 \ | | 1010 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1011 / | Source Port = xxxx | Dest Port = yyyy | 1012 UDP +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1013 \ | UDP Length | UDP Checksum | 1014 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1015 LCM | LISP Control Message | 1016 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1018 Packet header descriptions: 1020 OH: The outer IPv4 or IPv6 header, which uses RLOC addresses in the 1021 source and destination header address fields. 1023 UDP: The outer UDP header with destination port 4342. The source 1024 port is randomly allocated. The checksum field MUST be non- 1025 zero. 1027 LH: Type 8 is defined to be a "LISP Encapsulated Control Message", 1028 and what follows is either an IPv4 or IPv6 header as encoded by 1029 the first 4 bits after the 'Reserved' field. 1031 Type: 8 (Encapsulated Control Message (ECM)) 1033 S: This is the Security bit. When set to 1, the procedures from 1034 [I-D.ietf-lisp-sec] are followed. 1036 D: This is the DDT-bit. When set to 1, the sender is requesting a 1037 Map-Referral message to be returned. The details of this 1038 procedure are described in [I-D.ietf-lisp-ddt]. 1040 E: This is the to-ETR bit. When set to 1, the Map-Server's 1041 intention is to forward the ECM to an authoritative ETR. 1043 M: This is the to-MS bit. When set to 1, a Map-Request is being 1044 sent to a co-located Map-Resolver and Map-Server where the 1045 message can be processed directly by the Map-Server versus the 1046 Map-Resolver using the LISP-DDT procedures in 1047 [I-D.ietf-lisp-ddt]. 1049 0 1 2 3 1050 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 1051 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1052 | AD Type | Authentication Data Content . . . | 1053 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 1055 IH: The inner IPv4 or IPv6 header, which can use either RLOC or EID 1056 addresses in the header address fields. When a Map-Request is 1057 encapsulated in this packet format, the destination address in 1058 this header is an EID. 1060 UDP: The inner UDP header, where the port assignments depend on the 1061 control packet being encapsulated. When the control packet is 1062 a Map-Request or Map-Register, the source port is selected by 1063 the ITR/PITR and the destination port is 4342. When the 1064 control packet is a Map-Reply, the source port is 4342 and the 1065 destination port is assigned from the source port of the 1066 invoking Map-Request. Port number 4341 MUST NOT be assigned to 1067 either port. The checksum field MUST be non-zero. 1069 LCM: The format is one of the control message formats described in 1070 this section. At this time, only Map-Request messages are 1071 allowed to be encapsulated. In the future, PIM Join/Prune 1072 messages [RFC6831] might be allowed. Encapsulating other types 1073 of LISP control messages is for further study. When Map- 1074 Requests are sent for RLOC-Probing purposes (i.e., the probe- 1075 bit is set), they MUST NOT be sent inside Encapsulated Control 1076 Messages. 1078 5. Interactions with Other LISP Components 1080 5.1. ITR EID-to-RLOC Mapping Resolution 1082 An ITR is configured with one or more Map-Resolver addresses. These 1083 addresses are "Locators" (or RLOCs) and must be routable on the 1084 underlying core network; they must not need to be resolved through 1085 LISP EID-to-RLOC mapping, as that would introduce a circular 1086 dependency. When using a Map-Resolver, an ITR does not need to 1087 connect to any other database mapping system. In particular, the ITR 1088 need not connect to the LISP+ALT infrastructure or implement the BGP 1089 and GRE protocols that it uses. 1091 An ITR sends an Encapsulated Map-Request to a configured Map-Resolver 1092 when it needs an EID-to-RLOC mapping that is not found in its local 1093 map-cache. Using the Map-Resolver greatly reduces both the 1094 complexity of the ITR implementation and the costs associated with 1095 its operation. 1097 In response to an Encapsulated Map-Request, the ITR can expect one of 1098 the following: 1100 o An immediate Negative Map-Reply (with action code of "Natively- 1101 Forward", 15-minute Time to Live (TTL)) from the Map-Resolver if 1102 the Map-Resolver can determine that the requested EID does not 1103 exist. The ITR saves the EID-Prefix returned in the Map-Reply in 1104 its cache, marks it as non-LISP-capable, and knows not to attempt 1105 LISP encapsulation for destinations matching it. 1107 o A Negative Map-Reply, with action code of "Natively-Forward", from 1108 a Map-Server that is authoritative for an EID-Prefix that matches 1109 the requested EID but that does not have an actively registered, 1110 more-specific ID-prefix. In this case, the requested EID is said 1111 to match a "hole" in the authoritative EID-Prefix. If the 1112 requested EID matches a more-specific EID-Prefix that has been 1113 delegated by the Map-Server but for which no ETRs are currently 1114 registered, a 1-minute TTL is returned. If the requested EID 1115 matches a non-delegated part of the authoritative EID-Prefix, then 1116 it is not a LISP EID and a 15-minute TTL is returned. See 1117 Section 5.2 for discussion of aggregate EID-Prefixes and details 1118 of Map-Server EID-Prefix matching. 1120 o A LISP Map-Reply from the ETR that owns the EID-to-RLOC mapping or 1121 possibly from a Map-Server answering on behalf of the ETR. See 1122 Section 5.4 for more details on Map-Resolver message processing. 1124 Note that an ITR may be configured to both use a Map-Resolver and to 1125 participate in a LISP+ALT logical network. In such a situation, the 1126 ITR should send Map-Requests through the ALT network for any EID- 1127 Prefix learned via ALT BGP. Such a configuration is expected to be 1128 very rare, since there is little benefit to using a Map-Resolver if 1129 an ITR is already using LISP+ALT. There would be, for example, no 1130 need for such an ITR to send a Map-Request to a possibly non-existent 1131 EID (and rely on Negative Map-Replies) if it can consult the ALT 1132 database to verify that an EID-Prefix is present before sending that 1133 Map-Request. 1135 5.2. EID-Prefix Configuration and ETR Registration 1137 An ETR publishes its EID-Prefixes on a Map-Server by sending LISP 1138 Map-Register messages. A Map-Register message includes 1139 authentication data, so prior to sending a Map-Register message, the 1140 ETR and Map-Server must be configured with a shared secret or other 1141 relevant authentication information. A Map-Server's configuration 1142 must also include a list of the EID-Prefixes for which each ETR is 1143 authoritative. Upon receipt of a Map-Register from an ETR, a Map- 1144 Server accepts only EID-Prefixes that are configured for that ETR. 1145 Failure to implement such a check would leave the mapping system 1146 vulnerable to trivial EID-Prefix hijacking attacks. As developers 1147 and operators gain experience with the mapping system, additional, 1148 stronger security measures may be added to the registration process. 1150 In addition to the set of EID-Prefixes defined for each ETR that may 1151 register, a Map-Server is typically also configured with one or more 1152 aggregate prefixes that define the part of the EID numbering space 1153 assigned to it. When LISP+ALT is the database in use, aggregate EID- 1154 Prefixes are implemented as discard routes and advertised into ALT 1155 BGP. The existence of aggregate EID-Prefixes in a Map-Server's 1156 database means that it may receive Map Requests for EID-Prefixes that 1157 match an aggregate but do not match a registered prefix; Section 5.3 1158 describes how this is handled. 1160 Map-Register messages are sent periodically from an ETR to a Map- 1161 Server with a suggested interval between messages of one minute. A 1162 Map-Server should time out and remove an ETR's registration if it has 1163 not received a valid Map-Register message within the past 1164 three minutes. When first contacting a Map-Server after restart or 1165 changes to its EID-to-RLOC database mappings, an ETR may initially 1166 send Map-Register messages at an increased frequency, up to one every 1167 20 seconds. This "quick registration" period is limited to 1168 five minutes in duration. 1170 An ETR may request that a Map-Server explicitly acknowledge receipt 1171 and processing of a Map-Register message by setting the "want-map- 1172 notify" (M-bit) flag. A Map-Server that receives a Map-Register with 1173 this flag set will respond with a Map-Notify message. Typical use of 1174 this flag by an ETR would be to set it for Map-Register messages sent 1175 during the initial "quick registration" with a Map-Server but then 1176 set it only occasionally during steady-state maintenance of its 1177 association with that Map-Server. Note that the Map-Notify message 1178 is sent to UDP destination port 4342, not to the source port 1179 specified in the original Map-Register message. 1181 Note that a one-minute minimum registration interval during 1182 maintenance of an ETR-Map-Server association places a lower bound on 1183 how quickly and how frequently a mapping database entry can be 1184 updated. This may have implications for what sorts of mobility can 1185 be supported directly by the mapping system; shorter registration 1186 intervals or other mechanisms might be needed to support faster 1187 mobility in some cases. For a discussion on one way that faster 1188 mobility may be implemented for individual devices, please see 1189 [I-D.meyer-lisp-mn] 1191 An ETR may also request, by setting the "proxy Map-Reply" flag 1192 (P-bit) in the Map-Register message, that a Map-Server answer Map- 1193 Requests instead of forwarding them to the ETR. See 1194 [I-D.ietf-lisp-rfc6830bis] for details on how the Map-Server sets 1195 certain flags (such as those indicating whether the message is 1196 authoritative and how returned Locators should be treated) when 1197 sending a Map-Reply on behalf of an ETR. When an ETR requests proxy 1198 reply service, it should include all RLOCs for all ETRs for the EID- 1199 Prefix being registered, along with the routable flag ("R-bit") 1200 setting for each RLOC. The Map-Server includes all of this 1201 information in Map-Reply messages that it sends on behalf of the ETR. 1202 This differs from a non-proxy registration, since the latter need 1203 only provide one or more RLOCs for a Map-Server to use for forwarding 1204 Map-Requests; the registration information is not used in Map- 1205 Replies, so it being incomplete is not incorrect. 1207 An ETR that uses a Map-Server to publish its EID-to-RLOC mappings 1208 does not need to participate further in the mapping database 1209 protocol(s). When using a LISP+ALT mapping database, for example, 1210 this means that the ETR does not need to implement GRE or BGP, which 1211 greatly simplifies its configuration and reduces its cost of 1212 operation. 1214 Note that use of a Map-Server does not preclude an ETR from also 1215 connecting to the mapping database (i.e., it could also connect to 1216 the LISP+ALT network), but doing so doesn't seem particularly useful, 1217 as the whole purpose of using a Map-Server is to avoid the complexity 1218 of the mapping database protocols. 1220 5.3. Map-Server Processing 1222 Once a Map-Server has EID-Prefixes registered by its client ETRs, it 1223 can accept and process Map-Requests for them. 1225 In response to a Map-Request (received over the ALT if LISP+ALT is in 1226 use), the Map-Server first checks to see if the destination EID 1227 matches a configured EID-Prefix. If there is no match, the Map- 1228 Server returns a Negative Map-Reply with action code "Natively- 1229 Forward" and a 15-minute TTL. This may occur if a Map Request is 1230 received for a configured aggregate EID-Prefix for which no more- 1231 specific EID-Prefix exists; it indicates the presence of a non-LISP 1232 "hole" in the aggregate EID-Prefix. 1234 Next, the Map-Server checks to see if any ETRs have registered the 1235 matching EID-Prefix. If none are found, then the Map-Server returns 1236 a Negative Map-Reply with action code "Natively-Forward" and a 1237 1-minute TTL. 1239 If any of the registered ETRs for the EID-Prefix have requested proxy 1240 reply service, then the Map-Server answers the request instead of 1241 forwarding it. It returns a Map-Reply with the EID-Prefix, RLOCs, 1242 and other information learned through the registration process. 1244 If none of the ETRs have requested proxy reply service, then the Map- 1245 Server re-encapsulates and forwards the resulting Encapsulated Map- 1246 Request to one of the registered ETRs. It does not otherwise alter 1247 the Map-Request, so any Map-Reply sent by the ETR is returned to the 1248 RLOC in the Map-Request, not to the Map-Server. Unless also acting 1249 as a Map-Resolver, a Map-Server should never receive Map-Replies; any 1250 such messages should be discarded without response, perhaps 1251 accompanied by the logging of a diagnostic message if the rate of 1252 Map-Replies is suggestive of malicious traffic. 1254 5.4. Map-Resolver Processing 1256 Upon receipt of an Encapsulated Map-Request, a Map-Resolver 1257 decapsulates the enclosed message and then searches for the requested 1258 EID in its local database of mapping entries (statically configured 1259 or learned from associated ETRs if the Map-Resolver is also a Map- 1260 Server offering proxy reply service). If it finds a matching entry, 1261 it returns a LISP Map-Reply with the known mapping. 1263 If the Map-Resolver does not have the mapping entry and if it can 1264 determine that the EID is not in the mapping database (for example, 1265 if LISP+ALT is used, the Map-Resolver will have an ALT forwarding 1266 table that covers the full EID space), it immediately returns a 1267 negative LISP Map-Reply, with action code "Natively-Forward" and a 1268 15-minute TTL. To minimize the number of negative cache entries 1269 needed by an ITR, the Map-Resolver should return the least-specific 1270 prefix that both matches the original query and does not match any 1271 EID-Prefix known to exist in the LISP-capable infrastructure. 1273 If the Map-Resolver does not have sufficient information to know 1274 whether the EID exists, it needs to forward the Map-Request to 1275 another device that has more information about the EID being 1276 requested. To do this, it forwards the unencapsulated Map-Request, 1277 with the original ITR RLOC as the source, to the mapping database 1278 system. Using LISP+ALT, the Map-Resolver is connected to the ALT 1279 network and sends the Map-Request to the next ALT hop learned from 1280 its ALT BGP neighbors. The Map-Resolver does not send any response 1281 to the ITR; since the source RLOC is that of the ITR, the ETR or Map- 1282 Server that receives the Map-Request over the ALT and responds will 1283 do so directly to the ITR. 1285 5.4.1. Anycast Map-Resolver Operation 1287 A Map-Resolver can be set up to use "anycast", where the same address 1288 is assigned to multiple Map-Resolvers and is propagated through IGP 1289 routing, to facilitate the use of a topologically close Map-Resolver 1290 by each ITR. 1292 Note that Map-Server associations with ETRs should not use anycast 1293 addresses, as registrations need to be established between an ETR and 1294 a specific set of Map-Servers, each identified by a specific 1295 registration association. 1297 6. Security Considerations 1299 The 2-way LISP header nonce exchange documented in 1300 [I-D.ietf-lisp-rfc6830bis] can be used to avoid ITR spoofing attacks. 1302 To publish an authoritative EID-to-RLOC mapping with a Map-Server, an 1303 ETR includes authentication data that is a hash of the message using 1304 a pair-wise shared key. An implementation must support use of HMAC- 1305 SHA-1-96 [RFC2104] and should support use of HMAC-SHA-256-128 1306 [RFC6234] (SHA-256 truncated to 128 bits). 1308 As noted in Section 5.2, a Map-Server should verify that all EID- 1309 Prefixes registered by an ETR match the configuration stored on the 1310 Map-Server. 1312 The currently defined authentication mechanism for Map-Register 1313 messages does not provide protection against "replay" attacks by a 1314 "man-in-the-middle". Additional work is needed in this area. 1316 [I-D.ietf-lisp-sec] defines a proposed mechanism for providing origin 1317 authentication, integrity, anti-replay protection, and prevention of 1318 man-in-the-middle and "overclaiming" attacks on the Map-Request/Map- 1319 Reply exchange. Work is ongoing on this and other proposals for 1320 resolving these open security issues. 1322 While beyond the scope of securing an individual Map-Server or Map- 1323 Resolver, it should be noted that a BGP-based LISP+ALT network (if 1324 ALT is used as the mapping database infrastructure) can take 1325 advantage of standards work on adding security to BGP. 1327 A complete LISP threat analysis has been published in [RFC7835]. 1328 Please refer to it for more security related details. 1330 7. References 1332 7.1. Normative References 1334 [RFC1035] Mockapetris, P., "Domain names - implementation and 1335 specification", STD 13, RFC 1035, DOI 10.17487/RFC1035, 1336 November 1987, . 1338 [RFC2104] Krawczyk, H., Bellare, M., and R. Canetti, "HMAC: Keyed- 1339 Hashing for Message Authentication", RFC 2104, 1340 DOI 10.17487/RFC2104, February 1997, 1341 . 1343 [RFC2404] Madson, C. and R. Glenn, "The Use of HMAC-SHA-1-96 within 1344 ESP and AH", RFC 2404, DOI 10.17487/RFC2404, November 1345 1998, . 1347 [RFC4086] Eastlake 3rd, D., Schiller, J., and S. Crocker, 1348 "Randomness Requirements for Security", BCP 106, RFC 4086, 1349 DOI 10.17487/RFC4086, June 2005, 1350 . 1352 [RFC4107] Bellovin, S. and R. Housley, "Guidelines for Cryptographic 1353 Key Management", BCP 107, RFC 4107, DOI 10.17487/RFC4107, 1354 June 2005, . 1356 [RFC4868] Kelly, S. and S. Frankel, "Using HMAC-SHA-256, HMAC-SHA- 1357 384, and HMAC-SHA-512 with IPsec", RFC 4868, 1358 DOI 10.17487/RFC4868, May 2007, 1359 . 1361 [RFC6234] Eastlake 3rd, D. and T. Hansen, "US Secure Hash Algorithms 1362 (SHA and SHA-based HMAC and HKDF)", RFC 6234, 1363 DOI 10.17487/RFC6234, May 2011, 1364 . 1366 [RFC6831] Farinacci, D., Meyer, D., Zwiebel, J., and S. Venaas, "The 1367 Locator/ID Separation Protocol (LISP) for Multicast 1368 Environments", RFC 6831, DOI 10.17487/RFC6831, January 1369 2013, . 1371 [RFC6836] Fuller, V., Farinacci, D., Meyer, D., and D. Lewis, 1372 "Locator/ID Separation Protocol Alternative Logical 1373 Topology (LISP+ALT)", RFC 6836, DOI 10.17487/RFC6836, 1374 January 2013, . 1376 [RFC6837] Lear, E., "NERD: A Not-so-novel Endpoint ID (EID) to 1377 Routing Locator (RLOC) Database", RFC 6837, 1378 DOI 10.17487/RFC6837, January 2013, 1379 . 1381 [RFC7348] Mahalingam, M., Dutt, D., Duda, K., Agarwal, P., Kreeger, 1382 L., Sridhar, T., Bursell, M., and C. Wright, "Virtual 1383 eXtensible Local Area Network (VXLAN): A Framework for 1384 Overlaying Virtualized Layer 2 Networks over Layer 3 1385 Networks", RFC 7348, DOI 10.17487/RFC7348, August 2014, 1386 . 1388 [RFC7835] Saucez, D., Iannone, L., and O. Bonaventure, "Locator/ID 1389 Separation Protocol (LISP) Threat Analysis", RFC 7835, 1390 DOI 10.17487/RFC7835, April 2016, 1391 . 1393 [RFC8060] Farinacci, D., Meyer, D., and J. Snijders, "LISP Canonical 1394 Address Format (LCAF)", RFC 8060, DOI 10.17487/RFC8060, 1395 February 2017, . 1397 7.2. Informative References 1399 [AFI] IANA, , "Address Family Identifier (AFIs)", ADDRESS FAMILY 1400 NUMBERS http://www.iana.org/assignments/address-family- 1401 numbers/address-family-numbers.xhtml?, Febuary 2007. 1403 [I-D.ermagan-lisp-nat-traversal] 1404 Ermagan, V., Farinacci, D., Lewis, D., Skriver, J., Maino, 1405 F., and C. White, "NAT traversal for LISP", draft-ermagan- 1406 lisp-nat-traversal-12 (work in progress), March 2017. 1408 [I-D.ietf-lisp-ddt] 1409 Fuller, V., Lewis, D., Ermagan, V., Jain, A., and A. 1410 Smirnov, "LISP Delegated Database Tree", draft-ietf-lisp- 1411 ddt-09 (work in progress), January 2017. 1413 [I-D.ietf-lisp-introduction] 1414 Cabellos-Aparicio, A. and D. Saucez, "An Architectural 1415 Introduction to the Locator/ID Separation Protocol 1416 (LISP)", draft-ietf-lisp-introduction-13 (work in 1417 progress), April 2015. 1419 [I-D.ietf-lisp-rfc6830bis] 1420 Farinacci, D., Fuller, V., Meyer, D., Lewis, D., and A. 1421 Cabellos-Aparicio, "The Locator/ID Separation Protocol 1422 (LISP)", draft-ietf-lisp-rfc6830bis-01 (work in progress), 1423 March 2017. 1425 [I-D.ietf-lisp-sec] 1426 Maino, F., Ermagan, V., Cabellos-Aparicio, A., and D. 1427 Saucez, "LISP-Security (LISP-SEC)", draft-ietf-lisp-sec-12 1428 (work in progress), November 2016. 1430 [I-D.ietf-lisp-signal-free-multicast] 1431 Moreno, V. and D. Farinacci, "Signal-Free LISP Multicast", 1432 draft-ietf-lisp-signal-free-multicast-02 (work in 1433 progress), October 2016. 1435 [I-D.lewis-lisp-gpe] 1436 Lewis, D., Agarwal, P., Kreeger, L., Maino, F., Quinn, P., 1437 Smith, M., and N. Yadav, "LISP Generic Protocol 1438 Extension", draft-lewis-lisp-gpe-02 (work in progress), 1439 July 2014. 1441 [I-D.meyer-lisp-mn] 1442 Farinacci, D., Lewis, D., Meyer, D., and C. White, "LISP 1443 Mobile Node", draft-meyer-lisp-mn-16 (work in progress), 1444 December 2016. 1446 [I-D.portoles-lisp-eid-mobility] 1447 Portoles-Comeras, M., Ashtaputre, V., Moreno, V., Maino, 1448 F., and D. Farinacci, "LISP L2/L3 EID Mobility Using a 1449 Unified Control Plane", draft-portoles-lisp-eid- 1450 mobility-02 (work in progress), April 2017. 1452 [I-D.quinn-vxlan-gpe] 1453 Quinn, P., Manur, R., Kreeger, L., Lewis, D., Maino, F., 1454 Smith, M., Agarwal, P., Yong, L., Xu, X., Elzur, U., Garg, 1455 P., and D. Melman, "Generic Protocol Extension for VXLAN", 1456 draft-quinn-vxlan-gpe-04 (work in progress), February 1457 2015. 1459 [LISP-CONS] 1460 Brim, S., Chiappa, N., Farinacci, D., Fuller, V., Lewis, 1461 D., and D. Meyer, "LISP-CONS: A Content distribution 1462 Overlay Network Service for LISP", Work in Progress, April 1463 2008. 1465 Appendix A. Acknowledgments 1467 The authors would like to thank Greg Schudel, Darrel Lewis, John 1468 Zwiebel, Andrew Partan, Dave Meyer, Isidor Kouvelas, Jesper Skriver, 1469 Fabio Maino, and members of the lisp@ietf.org mailing list for their 1470 feedback and helpful suggestions. 1472 Special thanks are due to Noel Chiappa for his extensive work on 1473 caching with LISP-CONS, some of which may be used by Map-Resolvers. 1475 Appendix B. Document Change Log 1477 [RFC Editor: Please delete this section on publication as RFC.] 1479 B.1. Changes to draft-ietf-lisp-rfc6833bis-02 1481 o Posted April 2017. 1483 o Clarify that the LISP control-plane document defines how the LISP 1484 data-plane uses Map-Requests with either the SMR-bit set or the 1485 P-bit set supporting mapping updates and RLOC-probing. Indicating 1486 that other data-planes can use the same mechanisms or their own 1487 defined mechanisms to achieve the same functionality. 1489 B.2. Changes to draft-ietf-lisp-rfc6833bis-01 1491 o Posted March 2017. 1493 o Include references to new RFCs published. 1495 o Remove references to self. 1497 o Change references from RFC6830 to RFC6830bis. 1499 o Add two new action/reasons to a Map-Reply has posted to the LISP 1500 WG mailing list. 1502 o In intro section, add refernece to I-D.ietf-lisp-introduction. 1504 o Removed Open Issues section and references to "experimental". 1506 B.3. Changes to draft-ietf-lisp-rfc6833bis-00 1508 o Posted December 2016. 1510 o Created working group document from draft-farinacci-lisp 1511 -rfc6833-00 individual submission. No other changes made. 1513 B.4. Changes to draft-farinacci-lisp-rfc6833bis-00 1515 o Posted November 2016. 1517 o This is the initial draft to turn RFC 6833 into RFC 6833bis. 1519 o The document name has changed from the "Locator/ID Separation 1520 Protocol (LISP) Map-Server Interface" to the "Locator/ID 1521 Separation Protocol (LISP) Control-Plane". 1523 o The fundamental change was to move the control-plane messages from 1524 RFC 6830 to this document in an effort so any IETF developed or 1525 industry created data-plane could use the LISP mapping system and 1526 control-plane. 1528 o Update control-plane messages to incorporate what has been 1529 implemented in products during the early phase of LISP development 1530 but wasn't able to make it into RFC6830 and RFC6833 to make the 1531 Experimental RFC deadline. 1533 o Indicate there may be nodes in the mapping system that are not MRs 1534 or MSs, that is a ALT-node or a DDT-node. 1536 o Include LISP-DDT in Map-Resolver section and explain how they 1537 maintain a referral-cache. 1539 o Removed open issue about additional state in Map-Servers. With 1540 [I-D.ietf-lisp-ddt], Map-Servers have the same registration state 1541 and can give Map-Resolvers complete information in ms-ack Map- 1542 Referral messages. 1544 o Make reference to the LISP Threats Analysis RFC [RFC7835]. 1546 Authors' Addresses 1548 Vince Fuller 1549 Cisco Systems 1551 EMail: vaf@vaf.net 1553 Dino Farinacci 1554 Cisco Systems 1556 EMail: farinacci@gmail.com 1557 Albert Cabellos 1558 UPC/BarcelonaTech 1559 Campus Nord, C. Jordi Girona 1-3 1560 Barcelona, Catalunya 1561 Spain 1563 EMail: acabello@ac.upc.edu