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Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (26 November 2021) is 854 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) No issues found here. Summary: 2 errors (**), 0 flaws (~~), 1 warning (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group E. Chen 3 Internet-Draft Palo Alto Networks 4 Intended status: Standards Track N. Shen 5 Expires: 30 May 2022 Zededa 6 R. Raszuk 7 NTT Network Innovations 8 R. Rahman 9 26 November 2021 11 Unsolicited BFD for Sessionless Applications 12 draft-ietf-bfd-unsolicited-08 14 Abstract 16 For operational simplification of "sessionless" applications using 17 BFD, in this document we present procedures for "unsolicited BFD" 18 that allow a BFD session to be initiated by only one side, and be 19 established without explicit per-session configuration or 20 registration by the other side (subject to certain per-interface or 21 per-router policies). 23 We also introduce a new YANG module to configure and manage 24 "unsolicited BFD". The YANG module in this document conforms to the 25 Network Management Datastore Architecture (NMDA) [RFC8342]. 27 Requirements Language 29 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 30 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 31 "OPTIONAL" in this document are to be interpreted as described in BCP 32 14 [RFC2119] [RFC8174] when, and only when, they appear in all 33 capitals, as shown here. 35 Status of This Memo 37 This Internet-Draft is submitted in full conformance with the 38 provisions of BCP 78 and BCP 79. 40 Internet-Drafts are working documents of the Internet Engineering 41 Task Force (IETF). Note that other groups may also distribute 42 working documents as Internet-Drafts. The list of current Internet- 43 Drafts is at https://datatracker.ietf.org/drafts/current/. 45 Internet-Drafts are draft documents valid for a maximum of six months 46 and may be updated, replaced, or obsoleted by other documents at any 47 time. It is inappropriate to use Internet-Drafts as reference 48 material or to cite them other than as "work in progress." 49 This Internet-Draft will expire on 30 May 2022. 51 Copyright Notice 53 Copyright (c) 2021 IETF Trust and the persons identified as the 54 document authors. All rights reserved. 56 This document is subject to BCP 78 and the IETF Trust's Legal 57 Provisions Relating to IETF Documents (https://trustee.ietf.org/ 58 license-info) in effect on the date of publication of this document. 59 Please review these documents carefully, as they describe your rights 60 and restrictions with respect to this document. Code Components 61 extracted from this document must include Revised BSD License text as 62 described in Section 4.e of the Trust Legal Provisions and are 63 provided without warranty as described in the Revised BSD License. 65 Table of Contents 67 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 68 2. Procedures for Unsolicited BFD . . . . . . . . . . . . . . . 3 69 3. State Variables . . . . . . . . . . . . . . . . . . . . . . . 4 70 4. YANG Data Model . . . . . . . . . . . . . . . . . . . . . . . 5 71 4.1. Unsolicited BFD Hierarchy . . . . . . . . . . . . . . . . 5 72 4.2. Unsolicited BFD Module . . . . . . . . . . . . . . . . . 6 73 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 74 6. Acknowledgments . . . . . . . . . . . . . . . . . . . . . . . 10 75 7. Security Considerations . . . . . . . . . . . . . . . . . . . 10 76 7.1. BFD Protocol Security Considerations . . . . . . . . . . 10 77 7.2. YANG Module Security Considerations . . . . . . . . . . . 11 78 8. References . . . . . . . . . . . . . . . . . . . . . . . . . 12 79 8.1. Normative References . . . . . . . . . . . . . . . . . . 12 80 8.2. Informative References . . . . . . . . . . . . . . . . . 13 81 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 83 1. Introduction 85 The current implementation and deployment practice for BFD ([RFC5880] 86 and [RFC5881]) usually requires BFD sessions be explicitly configured 87 or registered on both sides. This requirement is not an issue when 88 an application like BGP [RFC4271] has the concept of a "session" that 89 involves both sides for its establishment. However, this requirement 90 can be operationally challenging when the prerequisite "session" does 91 not naturally exist between two endpoints in an application. 92 Simultaneous configuration and coordination may be required on both 93 sides for BFD to take effect. For example: 95 * When BFD is used to keep track of the "liveness" of the nexthop of 96 static routes. Although only one side may need the BFD 97 functionality, currently both sides need to be involved in 98 specific configuration and coordination and in some cases static 99 routes are created unnecessarily just for BFD. 100 * When BFD is used to keep track of the "liveness" of the third-pary 101 nexthop of BGP routes received from the Route Server [RFC7947] at 102 an Internet Exchange Point (IXP). As the third-party nexthop is 103 different from the peering address of the Route Server, for BFD to 104 work, currently two routers peering with the Route Server need to 105 have routes and nexthops from each other (although indirectly via 106 the Router Server), and the nexthop of each router must be present 107 at the same time. These issues are also discussed in 108 [I-D.ietf-idr-rs-bfd]. 110 Clearly it is beneficial and desirable to reduce or eliminate 111 unnecessary configurations and coordination in these "sessionless" 112 applications using BFD. 114 In this document we present procedures for "unsolicited BFD" that 115 allow a BFD session to be initiated by only one side, and be 116 established without explicit per-session configuration or 117 registration by the other side (subject to certain per-interface or 118 per-router policies). 120 With "unsolicited BFD" there is potential risk for excessive resource 121 usage by BFD from "unexpected" remote systems. To mitigate such 122 risks, several mechanisms are recommended in the Security 123 Considerations section. 125 Compared to the "Seamless BFD" [RFC7880], this proposal involves only 126 minor procedural enhancements to the widely deployed BFD itself. 127 Thus we believe that this proposal is inherently simpler in the 128 protocol itself and deployment. As an example, it does not require 129 the exchange of BFD discriminators over an out-of-band channel before 130 the BFD session bring-up. 132 When BGP Add-Path [RFC7911] is deployed at an IXP using the Route 133 Server, multiple BGP paths (when exist) can be made available to the 134 clients of the Router Server as described in [RFC7947]. The 135 "unsolicited BFD" can be used in BGP route selection by these clients 136 to eliminate paths with "inaccessible nexthops". 138 2. Procedures for Unsolicited BFD 140 With "unsolicited BFD", one side takes the "Active role" and the 141 other side takes only the "Passive role" as described in [RFC5880]. 143 On the passive side, the "unsolicited BFD" SHOULD be explicitly 144 configured on an interface or globally (apply to all interfaces). 145 The BFD parameters can be either per-interface or per-router based. 146 It MAY also choose to use the parameters that the active side uses in 147 its BFD Control packets. The "My Discriminator", however, MUST be 148 chosen to allow multiple unsolicited BFD sessions. 150 The active side starts sending the BFD Control packets as specified 151 in [RFC5880]. The passive side does not send BFD Control packets. 153 When the passive side receives a BFD Control packet from the active 154 side with 0 as "Your Discriminator" and does not find an existing BFD 155 session, the passive side MAY create a matching BFD session toward 156 the active side, if permitted by local configuration. 158 It would then start sending the BFD Control packets and perform 159 necessary procedure for bringing up, maintaining and tearing down the 160 BFD session. If the BFD session fails to get established within 161 certain specified time, or if an established BFD session goes down, 162 the passive side would stop sending BFD Control packets and MAY 163 delete the BFD session created until the BFD Control packets is 164 initiated by the active side again. 166 When an Unsolicited BFD session goes down, an implementation MAY 167 retain the session state for a period of time, which may be 168 configurable. Retaining this state can be useful for operational 169 purposes. 171 The "Passive role" may change to the "Active role" when a local 172 client registers for the same BFD session, and from the "Active role" 173 to the "Passive role" when there is no longer any locally registered 174 client for the BFD session. 176 3. State Variables 178 This document defines a new state variable called Unsolicited Role. 180 bfd.UnsolicitedRole 182 The operational mode of BFD interface when configured for unsolicited 183 behaviour. Options can be either PASSIVE, ACTIVE or NULL (NULL - not 184 initialized) for unsolicited BFD sessions. Default (not configured 185 for unsolicited behaviour) MUST be set to NULL if present on the 186 interface. 188 4. YANG Data Model 190 This section extends the YANG data model for BFD [RFC9127] to cover 191 unsolicited BFD. We import [RFC8349] since the "bfd" container in 192 [RFC9127] is under "control-plane-protocol". 194 4.1. Unsolicited BFD Hierarchy 196 Configuration for unsolicited BFD parameters for IP single-hop 197 sessions can be done at 2 levels: 199 * Globally, i.e. for all interfaces. This requires support for the 200 "unsolicited-params-global" feature. 201 * For specific interfaces. This requires support for the 202 "unsolicited-params-per-interface" feature. 204 For operational data, a new "unsolicited" container has been added 205 for BFD IP single-hop sessions. 207 The tree diagram below uses the graphical representation of data 208 models, as defined in [RFC8340]. 210 module: ietf-bfd-unsolicited 211 augment /rt:routing/rt:control-plane-protocols 212 /rt:control-plane-protocol/bfd:bfd/bfd-ip-sh:ip-sh: 213 +--rw unsolicited {bfd-unsol:unsolicited-params-global}? 214 +--rw enabled? boolean 215 +--rw local-multiplier? multiplier 216 +--rw (interval-config-type)? 217 +--:(tx-rx-intervals) 218 | +--rw desired-min-tx-interval? uint32 219 | +--rw required-min-rx-interval? uint32 220 +--:(single-interval) {single-minimum-interval}? 221 +--rw min-interval? uint32 222 augment /rt:routing/rt:control-plane-protocols 223 /rt:control-plane-protocol/bfd:bfd/bfd-ip-sh:ip-sh 224 /bfd-ip-sh:interfaces: 225 +--rw unsolicited {bfd-unsol:unsolicited-params-per-interface}? 226 +--rw enabled boolean 227 +--rw local-multiplier? multiplier 228 +--rw (interval-config-type)? 229 +--:(tx-rx-intervals) 230 | +--rw desired-min-tx-interval? uint32 231 | +--rw required-min-rx-interval? uint32 232 +--:(single-interval) {single-minimum-interval}? 233 +--rw min-interval? uint32 234 augment /rt:routing/rt:control-plane-protocols 235 /rt:control-plane-protocol/bfd:bfd/bfd-ip-sh:ip-sh 236 /bfd-ip-sh:sessions/bfd-ip-sh:session: 237 +--ro unsolicited 238 +--ro role? bfd-unsol:unsolicited-role 240 4.2. Unsolicited BFD Module 242 file "ietf-bfd-unsolicited@2021-11-23.yang" 243 module ietf-bfd-unsolicited { 245 yang-version 1.1; 247 namespace "urn:ietf:params:xml:ns:yang:ietf-bfd-unsolicited"; 249 prefix "bfd-unsol"; 251 // RFC Ed.: replace occurences of YYYY with actual RFC numbers 252 // and remove this note 254 import ietf-bfd-types { 255 prefix "bfd-types"; 256 reference 257 "RFC 9127: YANG Data Model for Bidirectional Forwarding Detection 258 (BFD)"; 259 } 261 import ietf-bfd { 262 prefix "bfd"; 263 reference 264 "RFC 9127: YANG Data Model for Bidirectional Forwarding Detection 265 (BFD)"; 266 } 268 import ietf-bfd-ip-sh { 269 prefix "bfd-ip-sh"; 270 reference 271 "RFC 9127: YANG Data Model for Bidirectional Forwarding Detection 272 (BFD)"; 273 } 275 import ietf-routing { 276 prefix "rt"; 277 reference 278 "RFC 8349: A YANG Data Model for Routing Management 279 (NMDA version)"; 280 } 282 organization "IETF BFD Working Group"; 284 contact 285 "WG Web: 286 WG List: 288 Editors: Enke Chen (enchen@paloaltonetworks.com), 289 Naiming Shen (naiming@zededa.com), 290 Robert Raszuk (robert@raszuk.net), 291 Reshad Rahman (reshad@yahoo.com)"; 293 description 294 "This module contains the YANG definition for BFD unsolicited 295 as per RFC YYYY. 297 Copyright (c) 2021 IETF Trust and the persons 298 identified as authors of the code. All rights reserved. 300 Redistribution and use in source and binary forms, with or 301 without modification, is permitted pursuant to, and subject 302 to the license terms contained in, the Simplified BSD License 303 set forth in Section 4.c of the IETF Trust's Legal Provisions 304 Relating to IETF Documents 305 (http://trustee.ietf.org/license-info). 307 This version of this YANG module is part of RFC YYYY; see 308 the RFC itself for full legal notices."; 310 reference "RFC YYYY"; 312 revision 2021-11-23 { 313 description 314 "Initial revision."; 315 reference 316 "RFC YYYY: Unsolicited BFD for Sessionless Applications."; 317 } 319 /* 320 * Feature definitions 321 */ 322 feature unsolicited-params-global { 323 description 324 "This feature indicates that the server supports global 325 parameters for unsolicited sessions."; 326 reference 327 "RFC YYYY: Unsolicited BFD for Sessionless Applications."; 328 } 330 feature unsolicited-params-per-interface { 331 description 332 "This feature indicates that the server supports per-interface 333 parameters for unsolicited sessions."; 334 reference 335 "RFC YYYY: Unsolicited BFD for Sessionless Applications."; 336 } 338 /* 339 * Type Definitions 340 */ 341 typedef unsolicited-role { 342 type enumeration { 343 enum unsolicited-active { 344 description "Active role"; 345 } 346 enum unsolicited-passive { 347 description "Passive role"; 348 } 349 } 350 description "Unsolicited role"; 351 } 352 /* 353 * Augments 354 */ 355 augment "/rt:routing/rt:control-plane-protocols/" 356 + "rt:control-plane-protocol/bfd:bfd/bfd-ip-sh:ip-sh" { 357 if-feature bfd-unsol:unsolicited-params-global; 358 description 359 "Augmentation for BFD unsolicited parameters"; 360 container unsolicited { 361 description 362 "BFD unsolicited top level container"; 363 leaf enabled { 364 type boolean; 365 default false; 366 description 367 "BFD unsolicited enabled globally for IP single-hop."; 368 } 369 uses bfd-types:base-cfg-parms; 370 } 371 } 373 augment "/rt:routing/rt:control-plane-protocols/" 374 + "rt:control-plane-protocol/bfd:bfd/bfd-ip-sh:ip-sh/" 375 + "bfd-ip-sh:interfaces" { 376 if-feature bfd-unsol:unsolicited-params-per-interface; 377 description 378 "Augmentation for BFD unsolicited on IP single-hop interface"; 379 container unsolicited { 380 description 381 "BFD IP single-hop interface unsolicited top level 382 container"; 383 leaf enabled { 384 type boolean; 385 default false; 386 description 387 "BFD unsolicited enabled on this interface."; 388 } 389 uses bfd-types:base-cfg-parms; 390 } 391 } 393 augment "/rt:routing/rt:control-plane-protocols/" 394 + "rt:control-plane-protocol/bfd:bfd/bfd-ip-sh:ip-sh/" 395 + "bfd-ip-sh:sessions/bfd-ip-sh:session" { 396 description 397 "Augmentation for BFD unsolicited on IP single-hop session"; 398 container unsolicited { 399 config false; 400 description 401 "BFD IP single-hop session unsolicited top level container"; 402 leaf role { 403 type bfd-unsol:unsolicited-role; 404 description "Role."; 405 } 406 } 407 } 408 } 409 411 5. IANA Considerations 413 This document registers the following namespace URI in the "IETF XML 414 Registry" [RFC3688]: 416 URI: urn:ietf:params:xml:ns:yang:ietf-bfd-unsolicited 418 Registrant Contact: The IESG. 420 XML: N/A; the requested URI is an XML namespace. 422 This document registers the following YANG module in the "YANG Module 423 Names" registry [RFC6020]: 425 Name: ietf-bfd-unsolicited 427 Namespace: urn:ietf:params:xml:ns:yang:ietf-bfd-unsolicited 429 Prefix: bfd-unsol 431 Reference: RFC YYYY 433 6. Acknowledgments 435 Authors would like to thank Acee Lindem, Greg Mirsky, Jeffrey Haas, 436 Raj Chetan and Tom Petch for their review and valuable input. 438 7. Security Considerations 440 7.1. BFD Protocol Security Considerations 442 The same security considerations and protection measures as those 443 described in [RFC5880] and [RFC5881] normatively apply to this 444 document. With "unsolicited BFD" there is potential risk for 445 excessive resource usage by BFD from "unexpected" remote systems. To 446 mitigate such risks, the following measures are mandatory: 448 * Limit the feature to specific interfaces, and to a single-hop BFD 449 with "TTL=255" [RFC5082]. For numbered interfaces, the source 450 address of an incoming BFD packet should belong to the subnet of 451 the interface on which the BFD packet is received. For unnumbered 452 interfaces the above check should be aligned with routing protocol 453 addresses running on such pair of interfaces. 454 * Apply "policy" to allow BFD packets only from certain subnets or 455 hosts. 456 * Deploy the feature only in certain "trustworthy" environment, 457 e.g., at an IXP, or between a provider and its customers. 458 * Adjust BFD parameters as needed for the particular deployment and 459 scale. 460 * Use BFD authentication. 462 7.2. YANG Module Security Considerations 464 The YANG module specified in this document defines a schema for data 465 that is designed to be accessed via network management protocols such 466 as NETCONF [RFC6241] or RESTCONF [RFC8040]. The lowest NETCONF layer 467 is the secure transport layer, and the mandatory-to-implement secure 468 transport is Secure Shell (SSH) [RFC6242]. The lowest RESTCONF layer 469 is HTTPS, and the mandatory-to-implement secure transport is TLS 470 [RFC8446]. 472 The NETCONF access control model [RFC8341] provides the means to 473 restrict access for particular NETCONF or RESTCONF users to a 474 preconfigured subset of all available NETCONF or RESTCONF protocol 475 operations and content. 477 There are a number of data nodes defined in this YANG module that are 478 writable/creatable/deletable (i.e., config true, which is the 479 default). These data nodes may be considered sensitive or vulnerable 480 in some network environments. Write operations (e.g., edit-config) 481 to these data nodes without proper protection can have a negative 482 effect on network operations. These are the subtrees and data nodes 483 and their sensitivity/vulnerability: 485 /routing/control-plane-protocols/control-plane-protocol/bfd/ip-sh 486 /unsolicited: 488 * data node "enabled" enables creation of unsolicited BFD IP single- 489 hop sessions globally, i.e. on all interfaces. See Section 7.1. 490 * data nodes local-multiplier, desired-min-tx-interval, required- 491 min-rx-interval and min-interval all impact the parameters of the 492 unsolicited BFD IP single-hop sessions. 494 /routing/control-plane-protocols/control-plane-protocol/bfd/ip-sh 495 /interfaces/interface/unsolicited: 497 * data node "enabled" enables creation of unsolicited BFD IP single- 498 hop sessions on a specific interface. See Section 7.1. 499 * data nodes local-multiplier, desired-min-tx-interval, required- 500 min-rx-interval and min-interval all impact the parameters of the 501 unsolicited BFD IP single-hop sessions on the interface. 503 Some of the readable data nodes in this YANG module may be considered 504 sensitive or vulnerable in some network environments. It is thus 505 important to control read access (e.g., via get, get-config, or 506 notification) to these data nodes. These are the subtrees and data 507 nodes and their sensitivity/vulnerability: 509 /routing/control-plane-protocols/control-plane-protocol/bfd/ip-sh 510 /sessions/session/unsolicited: access to this information discloses 511 the role of the local system in the creation of the unsolicited BFD 512 session. 514 8. References 516 8.1. Normative References 518 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 519 Requirement Levels", BCP 14, RFC 2119, 520 DOI 10.17487/RFC2119, March 1997, 521 . 523 [RFC3688] Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688, 524 DOI 10.17487/RFC3688, January 2004, 525 . 527 [RFC5082] Gill, V., Heasley, J., Meyer, D., Savola, P., Ed., and C. 528 Pignataro, "The Generalized TTL Security Mechanism 529 (GTSM)", RFC 5082, DOI 10.17487/RFC5082, October 2007, 530 . 532 [RFC5880] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 533 (BFD)", RFC 5880, DOI 10.17487/RFC5880, June 2010, 534 . 536 [RFC5881] Katz, D. and D. Ward, "Bidirectional Forwarding Detection 537 (BFD) for IPv4 and IPv6 (Single Hop)", RFC 5881, 538 DOI 10.17487/RFC5881, June 2010, 539 . 541 [RFC6020] Bjorklund, M., Ed., "YANG - A Data Modeling Language for 542 the Network Configuration Protocol (NETCONF)", RFC 6020, 543 DOI 10.17487/RFC6020, October 2010, 544 . 546 [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., 547 and A. Bierman, Ed., "Network Configuration Protocol 548 (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, 549 . 551 [RFC6242] Wasserman, M., "Using the NETCONF Protocol over Secure 552 Shell (SSH)", RFC 6242, DOI 10.17487/RFC6242, June 2011, 553 . 555 [RFC8040] Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF 556 Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017, 557 . 559 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 560 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 561 May 2017, . 563 [RFC8340] Bjorklund, M. and L. Berger, Ed., "YANG Tree Diagrams", 564 BCP 215, RFC 8340, DOI 10.17487/RFC8340, March 2018, 565 . 567 [RFC8341] Bierman, A. and M. Bjorklund, "Network Configuration 568 Access Control Model", STD 91, RFC 8341, 569 DOI 10.17487/RFC8341, March 2018, 570 . 572 [RFC8349] Lhotka, L., Lindem, A., and Y. Qu, "A YANG Data Model for 573 Routing Management (NMDA Version)", RFC 8349, 574 DOI 10.17487/RFC8349, March 2018, 575 . 577 [RFC8446] Rescorla, E., "The Transport Layer Security (TLS) Protocol 578 Version 1.3", RFC 8446, DOI 10.17487/RFC8446, August 2018, 579 . 581 [RFC9127] Rahman, R., Ed., Zheng, L., Ed., Jethanandani, M., Ed., 582 Pallagatti, S., and G. Mirsky, "YANG Data Model for 583 Bidirectional Forwarding Detection (BFD)", RFC 9127, 584 DOI 10.17487/RFC9127, October 2021, 585 . 587 8.2. Informative References 589 [I-D.ietf-idr-rs-bfd] 590 Bush, R., Haas, J., Scudder, J. G., Nipper, A., and C. 591 Dietzel, "Making Route Servers Aware of Data Link Failures 592 at IXPs", Work in Progress, Internet-Draft, draft-ietf- 593 idr-rs-bfd-09, 21 September 2020, 594 . 597 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 598 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 599 DOI 10.17487/RFC4271, January 2006, 600 . 602 [RFC7880] Pignataro, C., Ward, D., Akiya, N., Bhatia, M., and S. 603 Pallagatti, "Seamless Bidirectional Forwarding Detection 604 (S-BFD)", RFC 7880, DOI 10.17487/RFC7880, July 2016, 605 . 607 [RFC7911] Walton, D., Retana, A., Chen, E., and J. Scudder, 608 "Advertisement of Multiple Paths in BGP", RFC 7911, 609 DOI 10.17487/RFC7911, July 2016, 610 . 612 [RFC7947] Jasinska, E., Hilliard, N., Raszuk, R., and N. Bakker, 613 "Internet Exchange BGP Route Server", RFC 7947, 614 DOI 10.17487/RFC7947, September 2016, 615 . 617 [RFC8342] Bjorklund, M., Schoenwaelder, J., Shafer, P., Watsen, K., 618 and R. Wilton, "Network Management Datastore Architecture 619 (NMDA)", RFC 8342, DOI 10.17487/RFC8342, March 2018, 620 . 622 Authors' Addresses 624 Enke Chen 625 Palo Alto Networks 627 Email: enchen@paloaltonetworks.com 629 Naiming Shen 630 Zededa 632 Email: naiming@zededa.com 633 Robert Raszuk 634 NTT Network Innovations 635 940 Stewart Dr 636 Sunnyvale, CA 94085 637 United States of America 639 Email: robert@raszuk.net 641 Reshad Rahman 642 Canada 644 Email: reshad@yahoo.com