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Checking references for intended status: Experimental ---------------------------------------------------------------------------- ** Obsolete normative reference: RFC 6830 (Obsoleted by RFC 9300, RFC 9301) == Outdated reference: A later version (-15) exists of draft-farinacci-lisp-geo-00 == Outdated reference: A later version (-10) exists of draft-ietf-lisp-crypto-03 == Outdated reference: A later version (-22) exists of draft-ietf-lisp-lcaf-13 == Outdated reference: A later version (-29) exists of draft-ietf-lisp-sec-10 == Outdated reference: A later version (-09) exists of draft-ietf-lisp-signal-free-multicast-01 == Outdated reference: A later version (-02) exists of draft-portoles-lisp-eid-mobility-00 Summary: 1 error (**), 0 flaws (~~), 7 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group D. Farinacci 3 Internet-Draft lispers.net 4 Intended status: Experimental P. Pillay-Esnault 5 Expires: November 7, 2016 Huawei Technologies 6 May 6, 2016 8 LISP Predictive RLOCs 9 draft-farinacci-lisp-predictive-rlocs-00 11 Abstract 13 This specification will describe a method to achieve near-zero packet 14 loss when an EID is roaming quickly across RLOCs. 16 Requirements Language 18 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 19 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 20 document are to be interpreted as described in [RFC2119]. 22 Status of This Memo 24 This Internet-Draft is submitted in full conformance with the 25 provisions of BCP 78 and BCP 79. 27 Internet-Drafts are working documents of the Internet Engineering 28 Task Force (IETF). Note that other groups may also distribute 29 working documents as Internet-Drafts. The list of current Internet- 30 Drafts is at http://datatracker.ietf.org/drafts/current/. 32 Internet-Drafts are draft documents valid for a maximum of six months 33 and may be updated, replaced, or obsoleted by other documents at any 34 time. It is inappropriate to use Internet-Drafts as reference 35 material or to cite them other than as "work in progress." 37 This Internet-Draft will expire on November 7, 2016. 39 Copyright Notice 41 Copyright (c) 2016 IETF Trust and the persons identified as the 42 document authors. All rights reserved. 44 This document is subject to BCP 78 and the IETF Trust's Legal 45 Provisions Relating to IETF Documents 46 (http://trustee.ietf.org/license-info) in effect on the date of 47 publication of this document. Please review these documents 48 carefully, as they describe your rights and restrictions with respect 49 to this document. Code Components extracted from this document must 50 include Simplified BSD License text as described in Section 4.e of 51 the Trust Legal Provisions and are provided without warranty as 52 described in the Simplified BSD License. 54 Table of Contents 56 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 57 2. Definition of Terms . . . . . . . . . . . . . . . . . . . . . 3 58 3. Overview . . . . . . . . . . . . . . . . . . . . . . . . . . 3 59 4. Design Details . . . . . . . . . . . . . . . . . . . . . . . 5 60 4.1. RLE Encoding . . . . . . . . . . . . . . . . . . . . . . 5 61 4.2. Packet Delivery Optimizations . . . . . . . . . . . . . . 6 62 4.3. Trading Off Replication Cost . . . . . . . . . . . . . . 7 63 5. Directional Paths with Intersections . . . . . . . . . . . . 8 64 6. Multicast Considerations . . . . . . . . . . . . . . . . . . 9 65 7. Multiple Address-Family Considerations . . . . . . . . . . . 10 66 8. Scaling Considerations . . . . . . . . . . . . . . . . . . . 10 67 9. Security Considerations . . . . . . . . . . . . . . . . . . . 11 68 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 69 11. References . . . . . . . . . . . . . . . . . . . . . . . . . 11 70 11.1. Normative References . . . . . . . . . . . . . . . . . . 11 71 11.2. Informative References . . . . . . . . . . . . . . . . . 12 72 Appendix A. Acknowledgments . . . . . . . . . . . . . . . . . . 12 73 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 13 75 1. Introduction 77 The LISP architecture [RFC6830] specifies two namespaces, End-Point 78 IDs (EIDs) and Routing Locators (RLOCs). An EID identifies a node in 79 the network and the RLOC indicates the EID's topological location. 80 When an node roams in the network, its EID remains fixed and 81 unchanged but the RLOCs associated with it change to reflect its new 82 topological attachment point. This specification will focus EIDs and 83 RLOCs residing in separate nodes. An EID is assigned to a host node 84 that roams while the RLOCs are assigned to network nodes that stay 85 stationary and are part of the network topology. For example, a set 86 of devices on an aircraft are assigned EIDs, and base stations on the 87 ground attached to the Internet infrastructure are configured as LISP 88 xTRs where their RLOCs are used for the bindings of the EIDs on the 89 aircraft up in the air. 91 The scope of this specification will not emphasize general physical 92 roaming as an aircraft would do in the sky but in a direction that is 93 more predictable such as a train traveling on a track or vehicle that 94 travels along a road. 96 2. Definition of Terms 98 Roaming-EID - is a network node that moves from one topological 99 location in the network to another. The network node uses the 100 same EID when it is roaming. That is, the EID address does not 101 change for reasons of mobility. A roaming-EID can also be a 102 roaming EID-prefix where a set of EIDs covered by the prefix are 103 all roaming and fate-sharing the same set of RLOCs at the same 104 time. 106 Predictive RLOCs - is a set of ordered RLOCs in a list each assigned 107 to LISP xTRs where the next RLOC in the list has high probability 108 it will be the next LISP xTR in a physical path going in a single 109 predictable direction. 111 Road-Side-Units (RSUs) - is a network node that acts as a router, 112 more specifically as a LISP xTR. The xTR automatically discovers 113 roaming-EIDs that come into network connectivity range and relays 114 packets to and from the roaming-EID. RSUs are typically deployed 115 along a directional path like a train track or road and are in 116 connectivity range of devices that travel along the directional 117 path. 119 3. Overview 121 The goal of this specification is to describe a make-before-break 122 EID-mobility mechanism that offers near-zero packet loss. Offering 123 minimal packet loss, not only allows transport layers to operate more 124 efficiently, but because an EID does not change while moving, 125 transport layer session continuity is maintained. To achieve these 126 requirements, a mechanism that reacts to the mobility event is 127 necessary but not sufficient. So the question is not that there 128 isn't a reaction but when it happens. By using some predictive 129 algorithms, we can guess with high probability where the EID will 130 roam to next. We can achieve this to a point where packet data will 131 be at the new location when the EID arrives. 133 First we should examine both the send and receive directions with 134 respect to the roaming-EID. Refer to Figure 1 for discussion. We 135 show a network node with a fixed EID address assigned to a roaming- 136 EID moving along a train track. And there are LISP xTRs deployed as 137 Road-Side-Units to support the connectivity between the roaming-EID 138 and the infrastructure or to another roaming-EID. 140 Roaming-EID ----> 142 ====//====//====//====//====//====//====//====//===//====//====//==== 143 // // // // // // // // // // // 144 ====//====//====//====//====//====//====//====//===//====//====//==== 146 xTR xTR xTR xTR xTR xTR 147 A B C D E F 149 Figure 1: Directional Mobility 151 For the send direction from roaming-EID to any destination can be 152 accomplish as a local decision. As long as the roaming-EID is in 153 signal range to any xTR along the path, it can use it to forward 154 packets. The LISP xTR, acting as an ITR, can forward packets to 155 destinations in non-LISP sites as well as to stationary and roaming 156 EIDs in LISP sites. This is accomplished by using the LISP overlay 157 via dynamic packet encapsulation. When the roaming-EID sends 158 packets, the LISP xTR must discover the EID and MAY register the EID 159 with a set of RLOCs to the mapping system 160 [I-D.portoles-lisp-eid-mobility]. The discovery process is important 161 because the LISP xTR, acting as an ETR for decapsulating packets that 162 arrive, needs to know what local ports or radios to send packets to 163 the roaming-EID. 165 Much of the focus of this design is on the packet direction to the 166 roaming-EID. And how remote LISP ITRs find the current location 167 (RLOCs) quickly when the roaming-EID is moving at high speed. This 168 specification solves the fast roaming with the introduction of the 169 Predictive-RLOCs algorithm. 171 Since a safe assumption is that the roaming-EID is going in one 172 direction and cannot deviate from it allows us to know a priori the 173 next set of RLOCs the roaming-EID will pass by. Referring to 174 Figure 1, if the roaming-EID is in range near xTR-A, then as it 175 moves, it will at some point pass by xTR-B and xTR-C, and so on. As 176 the roaming-EID moves, one could time when the EID is mapped to RLOC 177 A, and when it should change to RLOC B and so on. However, the speed 178 of movement of the roaming-EID won't be constant and the variables 179 involved in consistent timing cannot be relied on. Furthermore, 180 timing the move is not a make-before-break algorithm, meaning the 181 reaction of the binding happens at the time the roaming-EID is 182 discovered by an xTR. One cannot achieve fast hand-offs when message 183 signaling will be required to inform remote ITRs of the new binding. 185 The Predictive RLOCs algorithm allows a set of RLOCs, in an ordered 186 list, to be provided to remote ITRs so they have the information 187 available and local for when they need to use it. Therefore, no 188 control-plane message signaling occurs when the roaming-EID is 189 discovered by LISP xTRs. 191 4. Design Details 193 Predictive RLOCs accommodates for encapsulated packets to be 194 delivered to Road-Side-Unit LISP xTRs regardless where the roaming- 195 EID is currently positioned. 197 Referring to Figure 1, the following sequence is performed: 199 1. The Predictive RLOCs are registered to the mapping system as a 200 LCAF encoded Replication List Entry (RLE) Type 201 [I-D.ietf-lisp-lcaf]. The registration can happen by one or more 202 RSUs or by a third-party. When registered by an RSU, and when no 203 coordination is desired, they each register their own RLOC with 204 merge-semantics so the list can be created and maintained in the 205 LISP Map-Server. When registered by a third-party, the complete 206 list of RLOCs can be included in the RLE. 208 2. There can be multiple RLEs present each as different RLOC- 209 records so a remote ITR can select one RLOC-record versus the 210 other based in priority and weight policy [RFC6830]. 212 3. When a remote ITR receives a packet destined for a roaming-EID, 213 it encapsulates and replicates to each RLOC in the RLE thereby 214 delivering the packet to the locations the roaming-EID is about 215 to appear. There are some cases where packets will go to 216 locations where the roaming-EID has already been, but see 217 Section 4.2 for packet delivery optimizations. 219 4. When the ETR resident RSU receives an encapsulated packet, it 220 decapsulates the packet and then determines if the roaming-EID 221 had been previously discovered. If the EID has not been 222 discovered, the ETR drops the packet. Otherwise, the ETR 223 delivers the decapsulated packet on the port interface the 224 roaming-EID was discovered on. 226 4.1. RLE Encoding 228 The LCAF [I-D.ietf-lisp-lcaf] Replication List Entry (RLE) will be 229 used to encode the Predictive RLOCs in an RLOC-record for Map- 230 Registers, Map-Reply, and Map-Notify messages [RFC6830]. 232 0 1 2 3 233 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 1 234 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 235 | AFI = 16387 | Rsvd1 | Flags | 236 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 237 | Type = 13 | Rsvd2 | 4 + n | 238 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 239 | Rsvd3 | Rsvd4 | Level Value | 240 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 241 | AFI = x | RTR/ETR #1 ... | 242 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 243 | Rsvd3 | Rsvd4 | Level Value | 244 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 245 | AFI = x | RTR/ETR #n ... | 246 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 248 When the RLOC-record contains an RLE with RLOC entries all with the 249 same level value, it means the physical order listed is the 250 directional path of the RSUs. This will typically be the result of a 251 third-party doing the registration where it knows ahead of time the 252 RSU deployment. 254 When each RSU is registering with merge-semantics on their own, the 255 level number is used to place them in an ordered list. Since the 256 registrations come at different times and therefore arrive in 257 different order than the physical RSU path, the level number creates 258 the necessary sequencing. Each RSU needs to know its position in the 259 path relative to other RSUs. For example, in xTR-B, it would 260 register with level 1 since it is after xTR-A (and before xTR-C). So 261 if the registration order was xTR-B with level 1, xTR-C with level 2, 262 and xTR-A with level 0, the RLE list stored in the mapping system 263 would be (xTR-A, xTR-B, xTR-C). It is recommended that level numbers 264 be assigned in increments of 10 so latter insertion is possible. 266 The use of Geo-Prefixes and Geo-Points can be used to compare the 267 physical presence of each RSU with respect to each other, so they can 268 choose level numbers to sequence themselves. Also if the xTRs 269 register with a Geo-Point in an RLOC-record, then perhaps the Map- 270 Server could sequence the RLE list. 272 4.2. Packet Delivery Optimizations 274 Since the remote ITR will replicate to all RLOCs in the RLE, a 275 situation is created where packets go to RLOCs that don't need to. 276 For instance, if the roaming-EID is along side of xTR-B and the RLE 277 is (xTR-A, xTR-B, xTR-C), there is no reason to replicate to xTR-A 278 since the roaming-EID has passed it and the the signal range is weak 279 or lost. However, replicating to xTR-B and xTR-C is important to 280 deliver packets to where the roaming-EID resides and where it is 281 about to go to. 283 A simple data-plane option, which converges fairly quickly is to have 284 the remote xTR, acting as an ETR, when packets are sent from the 285 roaming-EID, examine the source RLOC in the outer header of the 286 encapsulated packet. If the source RLOC is xTR-B, the remote xTR can 287 determine that the roaming-EID has moved past xTR-A and no longer 288 needs to encapsulate packets to xTR-A's RLOC. 290 In addition, the remote ITR can use RLOC-probing to determine if each 291 RLOC in the RLE is reachable. And if not reachable, exclude from the 292 list of RLOCs to replicate to. 294 This solution also handles the case where xTR-A and xTR-B may overlap 295 in radio signal range, but the signal is weak from the roaming-EID to 296 xTR-A but stronger to xTR-B. In this case, the roaming-EID selects 297 xTR-B to send packets that inform the remote xTR that return packets 298 should not be encapsulated to xTR-A. 300 There are also situations where the RSUs are in signal range of each 301 other in which case they could report reachability status of each 302 other. The use of the Locator-Status-Bits of the LISP encapsulation 303 header could be used to convey this information to the remote xTR. 304 This would only occur when the roaming-EID was discovered by both 305 xTR-A and xTR-B so it was possible for either xTR to reach the 306 roaming-EID. Either an IGP like routing protocol would be required 307 to allow each xTR to know the other could reach the roaming-EID or a 308 path trace tool (i.e. traceroute) could be originated by one xTR 309 targeted for the roaming-EID but MAC-forwarded through the other xTR. 310 These and other roaming-EID reachability mechanisms are work in 311 progress and for further study. 313 4.3. Trading Off Replication Cost 315 If RLE lists are large, packet replication can occur to locations 316 well before the roaming-EID arrives. Making RLE lists small is 317 useful without sacrificing hand-off issues or incurring packet loss 318 to the application. By having overlapping RLEs in separate RLOC- 319 records we a simple mechanism to solve this problem. Here is an 320 example mapping entry to illustrate the point: 322 EID = , RLOC-records: 323 RLOC = (RLE: xTR-A, xTR-B) 324 RLOC = (RLE: xTR-B, xTR-C, xTR-D, xTR-E) 325 RLOC = (RLE: xTR-E, xTR-F) 327 When the remote ITR is encapsulating to xTR-B as a decision to use 328 the first RLOC-record, it can decide to move to use the second RLOC- 329 record because xTR-B is the last entry in the first RLOC-record and 330 the first entry in the second RLOC-record. When there are 331 overlapping RLEs, the remote ITR can decide when it is more efficient 332 to switch over. For example, when the roaming-EID is in range of 333 xTR-A, the remote ITR uses the first RLOC-record so the wasted 334 replication cost is to xTR-B only versus a worse cost when using the 335 second RLOC-record. But when the roaming-EID is in range of xTR-B, 336 then replicating to the other xTRs in the second RLOC-record may be 337 crucial if the roaming-EID has increased speed. And when the 338 roaming-EID may be at rest in a parked mode, then the remote ITR 339 encapsulates to only xTR-F using the third RLOC-record since the 340 roaming-EID has moved past xTR-E. 342 In addition, to eliminate unnecessary replication to xTRs further 343 down a directional path, GEO-prefixes [I-D.farinacci-lisp-geo] can be 344 used so only nearby xTRs that the roaming-EID is about to come in 345 contact with are the only ones to receive encapsulated packets. 347 Even when replication lists are not large, we can reduce the cost of 348 replication that the entire network bears by moving the replicator 349 away from the the source (i.e. the ITR) and closer to the RSUs (i.e. 350 the ETRs). See the use of RTRs for Replication Engineering 351 techniques in [I-D.ietf-lisp-signal-free-multicast]. 353 5. Directional Paths with Intersections 355 A roaming-EID could be registered to the mapping system with the 356 following nested RLE mapping: 358 EID = , RLOC-records: 359 RLOC = (RLE: xTR-A, xTR-B, xTR-C, (RLE: xTR-X, xTR-Y, xTR-Z), 360 (RLE: xTR-I, xTR-J, xTR-K), xTR-D, xTR-E) 362 The mapping entry above describes 3 directional paths where the 363 ordered list has encoded one-level of two nested RLEs to denote 364 intersections in a horizontal path. Which is drawn as: 366 | | xTR-K 367 | | 368 | | 369 | | xTR-J 370 | | 371 | | 372 Roaming | | xTR-I 373 EID ----> | | 374 --------------------------------------- ------------------------------ 375 --------------------------------------- ------------------------------ 376 xTR-A xTR-B xTR-C | | xTR-D xTR-E 377 | | 378 | | xTR-X 379 | | 380 | | 381 | | xTR-Y 382 | | 383 | | 384 | | xTR-Z 386 When the roaming-EID is on the horizontal path, the remote-ITRs 387 typically replicate to the rest the of the xTRs in the ordered list. 388 When a list has nested RLEs, the replication should occur to at least 389 the first RLOC in a nested RLE list. So if the remote-ITR is 390 replicating to xTR-C, xTR-D, and xTR-E, it should also replicate to 391 xTR-X and xTR-I anticipating a possible turn at the intersection. 392 But when the roaming-EID is known to be at xTR-D (a left or right 393 hand turn was not taken), replication should only occur to xTR-D and 394 xTR-E. Once either xTR-I or xTR-X is determined to be where the 395 roaming-EID resides, then the replication occurs on the respective 396 directional path only. 398 When nested RLEs are used it may be difficult to get merge-semantics 399 to work when each xTR registers itself. So it is suggested a third- 400 party registers nested RLEs. It is left to further study to 401 understand better how to automate this. 403 6. Multicast Considerations 405 In this design, the remote ITR is receiving a unicast packet from an 406 EID and replicating and encapsulating to each RLOC in an RLE list. 407 This form of replication is no different than a traditional multicast 408 replication function. So replicating multicast packets in the same 409 fashion is a fallout from this design. 411 If there are multiple roaming-EIDs joined to the same multicast group 412 but reside at different RSUs, a merge has to be done of any pruned 413 RLEs used for forwarding. So if roaming-EID-1 resides at xTR-A and 414 roaming-EID-2 resides at xTR-B and the RLE list is (xTR-A, xTR-B, 415 xTR-C), and they are joined to the same multicast group, then 416 replication occurs to all of xTR-A, xTR-B, and xTR-C. Even since 417 roaming-EID-2 is past xTR-A, packets need to be delivered to xTR-A 418 for roaming-EID-1. In addition, packets need to be delivered to 419 xTR-C because roaming-EID-1 and roaming-EID-2 will get to xTR-C (and 420 roaming-EID-1 may get there sooner if it is traveling faster than 421 roaming-EID-2). 423 When a roaming-EID is a multicast source, procedures from 424 [I-D.ietf-lisp-signal-free-multicast] are used to deliver packets to 425 multicast group members anywhere in the network. The solution 426 requires no signaling to the RSUs. When RSUs receive multicast 427 packets from a roaming-EID, they do a (roaming-EID,G) mapping 428 database lookup to find the replication list of ETRs to encapsulate 429 to. 431 7. Multiple Address-Family Considerations 433 Note that roaming-EIDs can be assigned IPv6 EID addresses while the 434 RSU xTRs could be using IPv4 RLOC addresses. Any combination of 435 address-families can be supported as well as for multicast packet 436 forwarding, where (S,G) are IPv6 addresses entries and replication is 437 done with IPv4 RLOCs in the outer header. 439 8. Scaling Considerations 441 One can imagine there will be a large number of roaming-EIDs. So 442 there is a strong desire to efficiently store state in the mapping 443 database and the in remote ITRs map-caches. It is likely, that 444 roaming-EIDs may share the same path and move at the same speed (EID 445 devices on a train) and therefore share the same Predictive RLOCs. 446 And since EIDs are not reassigned for mobility purposes or may be 447 temporal , they will not be topologically aggregatable, so they 448 cannot compress into a single EID-prefix mapping entry that share the 449 same RLOC-set. 451 By using a level of indirection with the mapping system this problem 452 can be solved. The following mapping entries could exist in the 453 mapping database: 455 EID = , RLOC-records: 456 RLOC = (afi=: "am-train-to-paris") 457 EID = , RLOC-records: 458 RLOC = (afi=: "am-train-to-paris") 459 EID = , RLOC-records: 460 RLOC = (afi=: "am-train-to-paris") 462 EID = "am-train-to-paris", RLOC-records: 463 RLOC = (afi=lcaf/RLE-type: xTR-A, xTR-B, xTR-C) 465 EID = "am-train-to-paris-passengers", RLOC-records: 466 RLOC = (afi=lcaf/afi-list-type: , , ) 468 Each passenger that boards a train has their EID registered to point 469 to the name of the train "am-train-to-paris". And then the train 470 with EID "am-train-to-paris" stores the Predictive RLOC-set. When a 471 remote-ITR wants to encapsulate packets for an EID, it looks up the 472 EID in the mapping database gets the name "am-train-to-paris" 473 returned. Then the remote-ITR does another lookup for the name "am- 474 train-to-paris" to get the RLE list returned. 476 When new EIDs board the train, the RLE mapping entry does not need to 477 be modified. Only an EID-to-name mapping is registered for the 478 specific new EID. Optionally, another name "am-train-to-paris- 479 passengers" can be registered as an EID to allow mapping to all 480 specific EIDs which are on the train. This can be used for 481 inventory, billing, or security purposes. 483 This optimization comes at a cost of a 2-stage lookup. However, if 484 both sets of mapping entries are registered to the same Map-Server, a 485 combined RLOC-set could be returned. This idea is for further study. 487 9. Security Considerations 489 LISP has procedures for supporting both control-plane security 490 [I-D.ietf-lisp-sec] and data-plane security [I-D.ietf-lisp-crypto]. 492 10. IANA Considerations 494 At this time there are no requests for IANA. 496 11. References 498 11.1. Normative References 500 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 501 Requirement Levels", BCP 14, RFC 2119, 502 DOI 10.17487/RFC2119, March 1997, 503 . 505 [RFC6830] Farinacci, D., Fuller, V., Meyer, D., and D. Lewis, "The 506 Locator/ID Separation Protocol (LISP)", RFC 6830, 507 DOI 10.17487/RFC6830, January 2013, 508 . 510 11.2. Informative References 512 [I-D.farinacci-lisp-geo] 513 Farinacci, D., "LISP Geo-Coordinate Use-Cases", draft- 514 farinacci-lisp-geo-00 (work in progress), April 2016. 516 [I-D.ietf-lisp-crypto] 517 Farinacci, D. and B. Weis, "LISP Data-Plane 518 Confidentiality", draft-ietf-lisp-crypto-03 (work in 519 progress), December 2015. 521 [I-D.ietf-lisp-lcaf] 522 Farinacci, D., Meyer, D., and J. Snijders, "LISP Canonical 523 Address Format (LCAF)", draft-ietf-lisp-lcaf-13 (work in 524 progress), May 2016. 526 [I-D.ietf-lisp-sec] 527 Maino, F., Ermagan, V., Cabellos-Aparicio, A., and D. 528 Saucez, "LISP-Security (LISP-SEC)", draft-ietf-lisp-sec-10 529 (work in progress), April 2016. 531 [I-D.ietf-lisp-signal-free-multicast] 532 Moreno, V. and D. Farinacci, "Signal-Free LISP Multicast", 533 draft-ietf-lisp-signal-free-multicast-01 (work in 534 progress), April 2016. 536 [I-D.portoles-lisp-eid-mobility] 537 Portoles-Comeras, M., Ashtaputre, V., Moreno, V., Maino, 538 F., and D. Farinacci, "LISP L2/L3 EID Mobility Using a 539 Unified Control Plane", draft-portoles-lisp-eid- 540 mobility-00 (work in progress), April 2016. 542 Appendix A. Acknowledgments 544 The author would like to thank the LISP WG for their review and 545 acceptance of this draft. 547 Authors' Addresses 549 Dino Farinacci 550 lispers.net 551 San Jose, CA 552 USA 554 Email: farinacci@gmail.com 556 Padma Pillay-Esnault 557 Huawei Technologies 558 San Clara, CA 559 USA 561 Email: padma@huawei.com