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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group V. Moreno 3 Internet-Draft Cisco Systems 4 Intended status: Experimental D. Farinacci 5 Expires: June 17, 2015 lispers.net 6 December 14, 2014 8 Signal-Free LISP Multicast 9 draft-farinacci-lisp-signal-free-multicast-02 11 Abstract 13 When multicast sources and receivers are active at LISP sites, the 14 core network is required to use native multicast so packets can be 15 delivered from sources to group members. When multicast is not 16 available to connect the multicast sites together, a signal-free 17 mechanism can be used to allow traffic to flow between sites. The 18 mechanism within here uses unicast replication and encapsulation over 19 the core network for the data-plane and uses the LISP mapping 20 database system so encapsulators at the source LISP multicast site 21 can find de-capsulators at the receiver LISP multicast sites. 23 Requirements Language 25 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 26 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 27 document are to be interpreted as described in [RFC2119]. 29 Status of This Memo 31 This Internet-Draft is submitted in full conformance with the 32 provisions of BCP 78 and BCP 79. 34 Internet-Drafts are working documents of the Internet Engineering 35 Task Force (IETF). Note that other groups may also distribute 36 working documents as Internet-Drafts. The list of current Internet- 37 Drafts is at http://datatracker.ietf.org/drafts/current/. 39 Internet-Drafts are draft documents valid for a maximum of six months 40 and may be updated, replaced, or obsoleted by other documents at any 41 time. It is inappropriate to use Internet-Drafts as reference 42 material or to cite them other than as "work in progress." 44 This Internet-Draft will expire on June 17, 2015. 46 Copyright Notice 48 Copyright (c) 2014 IETF Trust and the persons identified as the 49 document authors. All rights reserved. 51 This document is subject to BCP 78 and the IETF Trust's Legal 52 Provisions Relating to IETF Documents 53 (http://trustee.ietf.org/license-info) in effect on the date of 54 publication of this document. Please review these documents 55 carefully, as they describe your rights and restrictions with respect 56 to this document. Code Components extracted from this document must 57 include Simplified BSD License text as described in Section 4.e of 58 the Trust Legal Provisions and are provided without warranty as 59 described in the Simplified BSD License. 61 Table of Contents 63 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 64 2. Definition of Terms . . . . . . . . . . . . . . . . . . . . . 4 65 3. Reference Model . . . . . . . . . . . . . . . . . . . . . . . 5 66 4. General Procedures . . . . . . . . . . . . . . . . . . . . . 6 67 4.1. General Receiver-site Procedures . . . . . . . . . . . . 7 68 4.1.1. Multicast receiver detection . . . . . . . . . . . . 7 69 4.1.2. Receiver-site Registration . . . . . . . . . . . . . 7 70 4.1.3. Consolidation of the replication-list . . . . . . . . 9 71 4.2. General Source-site Procedures . . . . . . . . . . . . . 9 72 4.2.1. Multicast Tree Building at the Source-site . . . . . 9 73 4.2.2. Multicast Destination Resolution . . . . . . . . . . 9 74 4.3. General LISP Notification Procedures . . . . . . . . . . 10 75 5. Source Specific Multicast Trees . . . . . . . . . . . . . . . 10 76 5.1. Source directly connected to Source-ITRs . . . . . . . . 11 77 5.2. Source not directly connected to Source-ITRs . . . . . . 11 78 6. PIM Any Source Multicast Trees . . . . . . . . . . . . . . . 11 79 7. Signal-Free Multicast for Replication Engineering . . . . . . 11 80 8. Security Considerations . . . . . . . . . . . . . . . . . . . 13 81 9. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 14 82 10. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 14 83 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 14 84 11.1. Normative References . . . . . . . . . . . . . . . . . . 14 85 11.2. Informative References . . . . . . . . . . . . . . . . . 14 86 Appendix A. Document Change Log . . . . . . . . . . . . . . . . 15 87 A.1. Changes to draft-farinacci-lisp-signal-free-multicast-02 15 88 A.2. Changes to draft-farinacci-lisp-signal-free-multicast-01 16 89 A.3. Changes to draft-farinacci-lisp-signal-free-multicast-00 16 90 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 16 92 1. Introduction 94 When multicast sources and receivers are active at LISP sites, and 95 the core network between the sites does not provide multicast 96 support, a signal-free mechanism can be used to create an overlay 97 that will allow multicast traffic to flow between sites and connect 98 the multicast trees at the different sites. 100 The signal-free mechanism here proposed does not extend PIM over the 101 overlay as proposed in [RFC6831], nor does the mechanism utilize 102 direct signaling between the Receiver-ETRs and Sender-ITRs as 103 described in [I-D.farinacci-lisp-mr-signaling]. The signal-free 104 mechanism proposed reduces the amount of signaling required between 105 sites to a minimum and is centered around the registration of 106 Receiver-sites for a particular multicast-group or multicast-channel 107 with the LISP Mapping System. 109 Registrations from the different receiver-sites will be merged at the 110 Mapping System to assemble a multicast-replication-list inclusive of 111 all RLOCs that lead to receivers for a particular multicast-group or 112 multicast-channel. The replication-list for each specific multicast- 113 entry is maintained as a LISP database mapping entry in the Mapping 114 Database. 116 When the ITR at the source-site receives multicast traffic from 117 sources at its site, the ITR can query the mapping system by issuing 118 Map-Request messages for the (S,G) source and destination addresses 119 in the packets received. The Mapping System will return the RLOC 120 replication-list to the ITR, which the ITR will cache as per standard 121 LISP procedure. Since the core is assumed to not support multicast, 122 the ITR will replicate the multicast traffic for each RLOC on the 123 replication-list and will unicast encapsulate the traffic to each 124 RLOC. The combined function or replicating and encapsulating the 125 traffic to the RLOCs in the replication-list is referred to as "rep- 126 encapsulation" in this document. 128 The document describes the General Procedures and information 129 encoding that are required at the Receiver-sites and Source-sites to 130 achieve signal-free multicast interconnectivity. The General 131 Procedures for Mapping System Notifications to different sites are 132 also described. A section dedicated to the specific case of SSM 133 trees discusses the implications to the General Procedures for SSM 134 multicast trees over different topological scenarios. At this stage 135 ASM trees are not supported with LISP Signal-Free multicast. 137 2. Definition of Terms 139 LISP related terms, notably Map-Request, Map-Reply, Ingress Tunnel 140 Router (ITR), Egress Tunnel Router (ETR), Map-Server (MS) and Map- 141 Resolver (MR) are defined in the LISP specification [RFC6830]. 143 Extensions to the definitions in [RFC6830] for their application to 144 multicast routing are documented in [RFC6831]. 146 Terms defining interactions with the LISP Mapping System are defined 147 in [RFC6833]. 149 The following terms are consistent with the definitions in [RFC6830] 150 and [RFC6831]. The terms are specific cases of the general terms and 151 are here defined to facilitate the descriptions and discussions 152 within this particular document. 154 Source: Multicast source end-point. Host originating multicast 155 packets. 157 Receiver: Multicast group member end-point. Host joins multicast 158 group as a receiver of multicast packets sent to the group. 160 Receiver-site: LISP site where multicast receivers are located. 162 Source-site: LISP site where multicast sources are located. 164 RP-site: LISP site where an ASM PIM Rendezvous Point is located. The 165 RP-site and the Source-site may be the same in some situations. 167 Receiver-ETR: LISP xTR at the Receiver-site. This is a multicast 168 ETR. 170 Source-ITR: LISP xTR at the Source-site. This is a multicast ITR. 172 RP-xTR: LISP xTR at the RP-site. This is typically a multicast ITR. 174 Replication-list: Mapping-entry containing the list of RLOCs that 175 have registered Receivers for a particular multicast-entry. 177 Multicast-entry: A tuple identifying a multicast tree. Multicast- 178 entries are in the form of (S-prefix, G-prefix). 180 Rep-encapsulation: The process of replicating and then encapsulating 181 traffic to multiple RLOCs. 183 3. Reference Model 185 The reference model that will be used for the discussion of the 186 Signal-Free multicast tree interconnection is illustrated in 187 Figure 1. 189 MS/MR 190 +---+ 191 | | 192 +---+ +---+ +---+ +---+ +---+ 193 Src-1-----| R1|-----|ITR| | |ETR|------| R2|-------Rcv-2 194 +---+ +---+ | +---+ +---+ 195 \ | / 196 Source-site-1 \ | / Receiver-site-2 197 \ | / 198 \ | / 199 \ | / 200 Core 201 / \ 202 / \ 203 / \ 204 / \ 205 / \ 206 +---+ +---+ 207 Src-3 --------------|ITR| |ETR|------------------Rcv-4 208 +---+ +---+ 210 Source-site-3 Receiver-site-4 212 Figure 1: LISP Multicast Generic Reference Model 214 Sites 1 and 3 are Source-sites. 216 Source-site-3 presents a Source (Src-3) that is directly connected to 217 the Source-ITR 219 Source-site-1 presents a Source (Src-1) that is one hop or more away 220 from the Source-ITR 222 Receiver-site-2 and 4 are receiver sites with not-directly connected 223 and directly connected Receiver end-points respectively 225 R1 is a router in Source-site-1. 227 R2 is a PIM router at the Receiver-site. 229 The Map-Servers and Resolvers are reachable in the RLOC space in the 230 Core, only one is shown for illustration purposes, but these can be 231 many or even part of a DDT tree. 233 The procedures for interconnecting multicast Trees over an overlay 234 can be broken down into three functional areas: 236 o Receiver-site procedures 238 o Source-site procedures 240 o LISP notification procedures 242 The receiver site procedures will be common for most tree types and 243 topologies. 245 The procedures at the source site can vary depending on the type of 246 trees being interconnected as well as based on the topological 247 relation between sources and source-site xTRs. For ASM trees, a 248 special case of the Source-site is the RP-site for which a variation 249 of the Source-site procedures may be necessary if ASM trees are to be 250 supported in future specifications of LISP Signal-Free multicast. 252 The LISP notification procedures between sites are normalized for the 253 different possible scenarios. Certain scenarios may benefit from a 254 simplified notification mechanism or no notification requirement at 255 all. 257 4. General Procedures 259 The interconnection of multicast trees across different LISP sites 260 involves the following procedures to build the necessary multicast 261 distribution trees across sites. 263 1. The presence of multicast Receiver end-points is detected by the 264 Receiver-ETRs at the Receiver-sites. 266 2. Receiver-ETRs register their RLOCs as part of the replication- 267 list for the multicast-entry the detected Receivers subscribe to. 269 3. The Mapping-system merges all receiver-ETR or delivery-group 270 RLOCs to build a comprehensive replication-list inclusive of all 271 Receiver-sites for each multicast-entry. 273 4. LISP Map-Notify messages should be sent to the Source-ITR 274 informing of any changes in the replication-list. 276 5. Multicast-tree building at the Source-site is initiated when the 277 Source-ITR receives the LISP Notification. 279 Once the multicast distribution trees are built, the following 280 forwarding procedures may take place: 282 1. The Source sends multicast packets to the multicast group 283 destination address. 285 2. Multicast traffic follows the multicast tree built at the Source- 286 site and makes its way to the Source-ITRs. 288 3. The Source-ITR will issue a map-request to resolve the 289 replication-list for the multicast-entry. 291 4. The Mapping System responds to the Source-ITR with a map-reply 292 containing the replication-list for the multicast group 293 requested. 295 5. The Source-ITR caches the replication-list received in the map- 296 reply for the multicast-entry. 298 6. Multicast traffic is rep-encapsulated. That is, the packet is 299 replicated for each RLOC in the replication-list and then 300 encapsulated to each one. 302 4.1. General Receiver-site Procedures 304 4.1.1. Multicast receiver detection 306 When the Receiver-ETRs are directly connected to the Receivers (e.g. 307 Receiver-site-4 in Figure 1), the Receiver-ETRs will receive IGMP 308 Reports from the Receivers indicating which group the Receivers wish 309 to subscribe to. Based on these IGMP Reports, the receiver-ETR is 310 made aware of the presence of Receivers as well as which group they 311 are interested in. 313 When the Receiver-ETRs are several hops away from the Receivers (e.g. 314 Receiver-site-2 in Figure 1), the Receiver-ETRs will receive PIM join 315 messages which will allow the Receiver-ETR to know that there are 316 multicast Receivers at the site and also learn which multicast group 317 the Receivers are for. 319 4.1.2. Receiver-site Registration 321 Once the Receiver-ETRs detect the presence of Receivers at the 322 Receiver-site, the Receiver-ETRs will issue Map-Register messages to 323 include the Receiver-ETR RLOCs in the replication-list for the 324 multicast-entry the Receivers joined. 326 The Map-Register message will use the multicast-entry (Source, Group) 327 tuple as its EID record type with the Receiver-ETR RLOCs conforming 328 the locator set. 330 The EID in the Map-Register message must be encoded using the 331 Multicast Information LCAF type defined in [I-D.ietf-lisp-lcaf]. The 332 R, L and J bits in the Multicast-info LCAF frame are not used and 333 should be set to zero. 335 The RLOC in the Map-Register message must be encoded using the 336 Replication List Entry (RLE) LCAF type defined in 337 [I-D.ietf-lisp-lcaf] with the Level Value fields for all entries set 338 to 128 (decimal). 340 The encoding described above must be used consistently for Map- 341 Register messages, entries in the Mapping Database, Map-reply 342 messages as well as the map-cache at the Source-ITRs. 344 The Map-Register messages [RFC6830] sent by the receiver-ETRs should 345 have the following bits set as here specified: 347 1. merge-request-bit set to 1. The Map-Register messages must be 348 sent with "Merge Semantics". The Map-Server will receive 349 registrations from a multitude of Receiver-ETRs. The Map-Server 350 will merge the registrations for common EIDs and maintain a 351 consolidated replication-list for each multicast-entry. 353 2. want-map-notify-bit (M) set to 0. This tells the Mapping System 354 that the receiver-ETR does not expect to receive Map-Notify 355 messages as it does not need to be notified of all changes to the 356 replication-list. 358 3. proxy-reply-bit (P) set to 1. The merged replication-list is 359 kept in the Map-Servers. By setting the proxy-reply bit, the 360 receiver-ETRs instruct the Mapping-system to proxy reply to map- 361 requests issued for the multicast entries. 363 Map-Register messages for a particular multicast-entry should be sent 364 for every receiver detected, even if previous receivers have been 365 detected for the particular multicast-entry. This allows the 366 replication-list to remain up to date. 368 4.1.3. Consolidation of the replication-list 370 The Map-Server will receive registrations from a multitude of 371 Receiver-ETRs. The Map-Server will merge the registrations for 372 common EIDs and consolidate a replication-list for each multicast- 373 entry. 375 4.2. General Source-site Procedures 377 Source-ITRs must register the unicast EIDs of any Sources or 378 Rendezvous Points that may be present on the Source-site. In other 379 words, it is assumed that the Sources and RPs are LISP EIDs. 381 The registration of the unicast EIDs for the Sources or Rendezvous 382 Points allows the map-server to know where to send Map-Notify 383 messages to. Therefore, the Source-ITR must register the unicast 384 S-prefix EID with the want-map-notify-bit set in order to receive 385 Map-Notify messages whenever there is a change in the replication- 386 list. 388 4.2.1. Multicast Tree Building at the Source-site 390 When the source site receives the Map-Notify messages from the 391 mapping system as described in Section 4.3, it will initiate the 392 process of building a multicast distribution tree that will allow the 393 multicast packets from the Source to reach the Source-ITR. 395 The Source-ITR will issue a PIM join for the multicast-entry for 396 which it received the Map-Notify message. The join will be issued in 397 the direction of the source or in the direction of the RP for the SSM 398 and ASM cases respectively. 400 4.2.2. Multicast Destination Resolution 402 On reception of multicast packets, the source-ITR must obtain the 403 replication-list for the (S,G) addresses in the packets. 405 In order to obtain the replication-list, the Source-ITR must issue a 406 Map-Request message in which the EID is the (S,G) multicast tuple 407 which is encoded using the Multicast Info LCAF type defined in 408 [I-D.ietf-lisp-lcaf]. 410 The Mapping System (most likely the Map-Server) will Map-reply with 411 the merged replication-list maintained in the Mapping System. The 412 Map-reply message must follow the format defined in [RFC6830], its 413 EID must be encoded using the Multicast Info LCAF type and the 414 corresponding RLOC-records must be encoded using the RLE LCAF type. 415 Both LCAF types defined in [I-D.ietf-lisp-lcaf]. 417 4.3. General LISP Notification Procedures 419 The Map-Server will issue LISP Map-Notify messages to inform the 420 Source-site of the presence of receivers for a particular multicast 421 group over the overlay. 423 Updated Map-Notify messages should be issued every time a new 424 registration is received from a Receiver-site. This guarantees that 425 the source-sites are aware of any potential changes in the multicast- 426 distribution-list membership. 428 The Map-Notify messages carry (S,G) multicast EIDs encoded using the 429 Multicast Info LCAF type defined in [I-D.ietf-lisp-lcaf]. 431 Map-Notify messages will be sent by the Map-Server to the RLOCs with 432 which the unicast S-prefix EID was registered. 434 When both the Receiver-sites and the Source-sites register to the 435 same Map-Server, the Map-Server has all the necessary information to 436 send the Map-Notify messages to the Source-site. 438 When the Map-Servers are distributed in a DDT, the Receiver-sites may 439 register to one Map-Server while the Source-site registers to a 440 different Map-Server. In this scenario, the Map-Server for the 441 receiver sites must resolve the unicast S-prefix EID in the DDT per 442 standard LISP lookup procedures and obtain the necessary information 443 to send the Map-Notify messages to the Source-site. The Map-Notify 444 messages must be sent with an authentication length of 0 as they 445 would not be authenticated. 447 When the Map-Servers are distributed in a DDT, different Receiver- 448 sites may register to different Map-Servers. This is an unsupported 449 scenario with the currently defined mechanisms. 451 5. Source Specific Multicast Trees 453 The interconnection of Source Specific Multicast (SSM) Trees across 454 sites will follow the General Receiver-site Procedures described in 455 Section 4.1 on the Receiver-sites. 457 The Source-site Procedures will vary depending on the topological 458 location of the Source within the Source-site as described in 459 Section 5.1 and Section 5.2 . 461 5.1. Source directly connected to Source-ITRs 463 When the Source is directly connected to the source-ITR, it is not 464 necessary to trigger signaling to build a local multicast tree at the 465 Source-site. Therefore Map-Notify messages may not be required to 466 initiate building of the multicast tree at the Source-site. 468 Map-Notify messages are still required to ensure that any changes to 469 the replication-list are communicated to the Source-site so that the 470 map-cache at the Source-ITRs is kept updated. 472 5.2. Source not directly connected to Source-ITRs 474 The General LISP Notification Procedures described in Section 4.3 475 must be followed when the Source is not directly connected to the 476 source-ITR. On reception of Map-Notify messages, local multicast 477 signaling must be initiated at the Source-site per the General Source 478 Site Procedures for Multicast Tree building described in 479 Section 4.2.1. 481 In the SSM case, the IP address of the Source is known and it is also 482 registered with the LISP mapping system. Thus, the mapping system 483 may resolve the mapping for the Source address in order to send Map- 484 Notify messages to the correct source-ITR. 486 6. PIM Any Source Multicast Trees 488 LISP signal-free multicast will not support ASM Trees at this time. 489 A future revision of this specification may include procedures for 490 PIM ASM support. 492 PIM ASM in shared-tree only mode could be supported in the scenario 493 where the root of the shared tree (the PIM RP) is placed at the 494 source site. 496 7. Signal-Free Multicast for Replication Engineering 498 The mechanisms in this draft can be applied to the LISP Replication- 499 Engineering [I-D.coras-lisp-re] design. Rather than having the 500 layered LISP-RE RTR hierarchy use signaling mechanisms, the RTRs can 501 register their availability for multicast tree replication via the 502 mapping database system. As stated in [I-D.coras-lisp-re], the RTR 503 layered hierarchy is used to avoid head-end replication in 504 replicating nodes closest to a multicast source. Rather than have 505 multicast ITRs replicate to each ETR in an RLE entry of a (S,G) 506 mapping database entry, it could replicate to one or more layer-0 507 RTRs in the LISP-RE hierarchy. 509 There are two formats an (S,G) mapping database entry could have. 510 One format is a 'complete-format' and the other is a 'filtered- 511 format'. A 'complete-format' entails an (S,G) entry having multiple 512 RLOC records which contain both ETRs that have registered as well as 513 the RTRs at the first level of the LISP-RE hierarchy for the ITR to 514 replicate to. When using 'complete-format', the ITR has the ability 515 to select if it replicates to RTRs or to the registered ETRs at the 516 receiver sites. A 'filtered-format' (S,G) entry is one where the 517 Map-Server returns the RLOC-records that it decides the ITR should 518 use. So replication policy is shifted from the ITRs to the mapping 519 system. The Map-Servers can also decide for a given ITR, if it uses 520 a different set of replication targets per (S,G) entry for which the 521 ITR is replicating for. 523 The procedure for the LISP-RE RTRs to make themselves available for 524 replication can occur before or after any receivers join an (S,G) 525 entry or any sources send for a particular (S,G) entry. Therefore, 526 newly configured RTR state will be used to create new (S,G) state and 527 inherited into existing (S,G) state. A set of RTRs can register 528 themselves to the mapping system or a third-party can do so on their 529 behalf. When RTR registration occurs, it is done with an (S-prefix, 530 G-prefix) entry so it can advertise its replication services for a 531 wide-range of source/group combinations. 533 When a Map-Server receives (S,G) registrations from ETRs and 534 (S-prefix, G-prefix) registrations from RTRs, it has the option of 535 merging the RTR RLOC-records for each (S,G) that is more-specific for 536 the (S-prefix, G-prefix) entry or keep them separate. When merging, 537 a Map-Server is ready to return a 'complete-format' Map-Reply. When 538 keeping the entries separate, the Map-Server can decide what to 539 include in a Map-Reply when a Map-Request is received. It can 540 include a combination of RLOC-records from each entry or decide to 541 use one or the other depending on policy configured. 543 Here is a specific example of (S,G) and (S-prefix, G-prefix) mapping 544 database entries when a source S is behind an ITR and there are 545 receiver sites joined to (S,G) via ETR1, ETR2, and ETR3. And there 546 exists a LISP-RE hierarchy of RTR1 and RTR2 at level-0 and RTR3 and 547 RTR4 at level-1: 549 EID-record: (S,G) 550 RLOC-record: RLE: (ETR1, ETR2, ETR3), p1 551 EID-record: (S-prefix, G-prefix) 552 RLOC-record: RLE: (RTR1(L0), RTR2(L0), RTR3(L1), RTR4(L1)), p1 554 The above entries are in the form of how they were registered and 555 stored in a Map-Server. When a Map-Server uses 'complete-format', a 556 Map-Reply it originates has the mapping record encoded as: 558 EID-record: (S,G) 559 RLOC-record: RLE: (RTR1(L0), RTR3(L1)), p1 560 RLOC-record: RLE: (ETR1, ETR2, ETR3), p1 562 The above Map-Reply allows the ITR to decide if it replicates to the 563 ETRs or if it should replicate only to level-0 RTR1. This decision 564 is left to the ITR since both RLOC-records have priority 1. If the 565 Map-Server wanted to force the ITR to replicate to RTR1, it would set 566 the ETRs RLOC-record to priority greater than 1. 568 When a Map_server uses "filtered-format', a Map-Reply it originates 569 has the mapping record encoded as: 571 EID-record: (S,G) 572 RLOC-record: RLE: (RTR1(L0), RTR3(L1)), p1 574 An (S,G) entry can contain alternate RTRs. So rather than 575 replicating to multiple RTRs, one of a RTR set may be used based on 576 the RTR reachability status. An ITR can test reachability status to 577 any layer-0 RTR using RLOC-probing so it can choose one RTR from a 578 set to replicate to. When this is done the RTRs are encoded in 579 different RLOC-records versus together in one RLE RLOC-record. This 580 moves the replication load off the ITRs at the source site to the 581 RTRs inside the network infrastructure. This mechanism can also be 582 used by level-n RTRs to level-n+1 RTRs. 584 The following mapping would be encoded in a Map-Reply sent by a Map- 585 Server and stored in the ITR. The ITR would use RTR1 until it went 586 unreachable and then switch to use RTR2: 588 EID-record: (S,G) 589 RLOC-record: RTR1, p1 590 RLOC-record: RTR2, p2 592 8. Security Considerations 594 [I-D.ietf-lisp-sec] defines a set of security mechanisms that provide 595 origin authentication, integrity and anti-replay protection to LISP's 596 EID-to-RLOC mapping data conveyed via mapping lookup process. LISP- 597 SEC also enables verification of authorization on EID-prefix claims 598 in Map-Reply messages. 600 Additional security mechanisms to protect the LISP Map-Register 601 messages are defined in [RFC6833]. 603 The security of the Mapping System Infrastructure depends on the 604 particular mapping database used. The [I-D.ietf-lisp-ddt] 605 specification, as an example, defines a public-key based mechanism 606 that provides origin authentication and integrity protection to the 607 LISP DDT protocol. 609 Map-Replies received by the source-ITR can be signed (by the Map- 610 Server) so the ITR knows the replication-list is from a legit source. 612 Data-plane encryption can be used when doing unicast rep- 613 encapsulation as described in [I-D.farinacci-lisp-crypto]. For 614 further study we will look how to do multicast rep-encapsulation. 616 9. IANA Considerations 618 This document has no IANA implications 620 10. Acknowledgements 622 The authors want to thank Greg Shepherd, Joel Halpern and Sharon 623 Barkai for their insightful contribution to shaping the ideas in this 624 document. Thanks also goes to Jimmy Kyriannis, Paul Vinciguerra, and 625 Florin Coras for testing an implementation of this draft. 627 11. References 629 11.1. Normative References 631 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 632 Requirement Levels", BCP 14, RFC 2119, March 1997. 634 [RFC3618] Fenner, B. and D. Meyer, "Multicast Source Discovery 635 Protocol (MSDP)", RFC 3618, October 2003. 637 [RFC4601] Fenner, B., Handley, M., Holbrook, H., and I. Kouvelas, 638 "Protocol Independent Multicast - Sparse Mode (PIM-SM): 639 Protocol Specification (Revised)", RFC 4601, August 2006. 641 [RFC4607] Holbrook, H. and B. Cain, "Source-Specific Multicast for 642 IP", RFC 4607, August 2006. 644 11.2. Informative References 646 [I-D.coras-lisp-re] 647 Coras, F., Cabellos-Aparicio, A., Domingo-Pascual, J., 648 Maino, F., and D. Farinacci, "LISP Replication 649 Engineering", draft-coras-lisp-re-06 (work in progress), 650 October 2014. 652 [I-D.farinacci-lisp-crypto] 653 Farinacci, D., "LISP Data-Plane Confidentiality", draft- 654 farinacci-lisp-crypto-01 (work in progress), July 2014. 656 [I-D.farinacci-lisp-mr-signaling] 657 Farinacci, D. and M. Napierala, "LISP Control-Plane 658 Multicast Signaling", draft-farinacci-lisp-mr-signaling-05 659 (work in progress), August 2014. 661 [I-D.ietf-lisp-ddt] 662 Fuller, V., Lewis, D., Ermagan, V., and A. Jain, "LISP 663 Delegated Database Tree", draft-ietf-lisp-ddt-02 (work in 664 progress), October 2014. 666 [I-D.ietf-lisp-lcaf] 667 Farinacci, D., Meyer, D., and J. Snijders, "LISP Canonical 668 Address Format (LCAF)", draft-ietf-lisp-lcaf-07 (work in 669 progress), December 2014. 671 [I-D.ietf-lisp-sec] 672 Maino, F., Ermagan, V., Cabellos-Aparicio, A., and D. 673 Saucez, "LISP-Security (LISP-SEC)", draft-ietf-lisp-sec-07 674 (work in progress), October 2014. 676 [RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The 677 Locator/ID Separation Protocol (LISP)", RFC 6830, January 678 2013. 680 [RFC6831] Farinacci, D., Meyer, D., Zwiebel, J., and S. Venaas, "The 681 Locator/ID Separation Protocol (LISP) for Multicast 682 Environments", RFC 6831, January 2013. 684 [RFC6833] Fuller, V. and D. Farinacci, "Locator/ID Separation 685 Protocol (LISP) Map-Server Interface", RFC 6833, January 686 2013. 688 Appendix A. Document Change Log 690 A.1. Changes to draft-farinacci-lisp-signal-free-multicast-02 692 o Posted December 2014. 694 o Added section about how LISP-RE can use the mechanisms from 695 signal-free-multicast so we can avoid head-end replication and 696 avoid signalling across a layered RE topology. 698 A.2. Changes to draft-farinacci-lisp-signal-free-multicast-01 700 o Posted June 2014. 702 o Changes based on implementation experience of this draft. 704 A.3. Changes to draft-farinacci-lisp-signal-free-multicast-00 706 o Posted initial draft February 2014. 708 Authors' Addresses 710 Victor Moreno 711 Cisco Systems 712 170 Tasman Drive 713 San Jose, California 95134 714 USA 716 Email: vimoreno@cisco.com 718 Dino Farinacci 719 lispers.net 720 San Jose, CA 95120 721 USA 723 Email: farinacci@gmail.com