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Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) == Unused Reference: 'RFC5226' is defined on line 593, but no explicit reference was found in the text ** Obsolete normative reference: RFC 5226 (Obsoleted by RFC 8126) Summary: 1 error (**), 0 flaws (~~), 3 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Global Routing Operations T. Evens 3 Internet-Draft S. Bayraktar 4 Updates: 7854 (if approved) M. Bhardwaj 5 Intended status: Standards Track Cisco Systems 6 Expires: 16 December 2021 P. Lucente 7 NTT Communications 8 14 June 2021 10 Support for Local RIB in BGP Monitoring Protocol (BMP) 11 draft-ietf-grow-bmp-local-rib-12 13 Abstract 15 The BGP Monitoring Protocol (BMP) defines access to local Routing 16 Information Bases (RIBs). This document updates BMP (RFC 7854) by 17 adding access to the Local Routing Information Base (Loc-RIB), as 18 defined in RFC 4271. The Loc-RIB contains the routes that have been 19 selected by the local BGP speaker's Decision Process. 21 Status of This Memo 23 This Internet-Draft is submitted in full conformance with the 24 provisions of BCP 78 and BCP 79. 26 Internet-Drafts are working documents of the Internet Engineering 27 Task Force (IETF). Note that other groups may also distribute 28 working documents as Internet-Drafts. The list of current Internet- 29 Drafts is at https://datatracker.ietf.org/drafts/current/. 31 Internet-Drafts are draft documents valid for a maximum of six months 32 and may be updated, replaced, or obsoleted by other documents at any 33 time. It is inappropriate to use Internet-Drafts as reference 34 material or to cite them other than as "work in progress." 36 This Internet-Draft will expire on 16 December 2021. 38 Copyright Notice 40 Copyright (c) 2021 IETF Trust and the persons identified as the 41 document authors. All rights reserved. 43 This document is subject to BCP 78 and the IETF Trust's Legal 44 Provisions Relating to IETF Documents (https://trustee.ietf.org/ 45 license-info) in effect on the date of publication of this document. 46 Please review these documents carefully, as they describe your rights 47 and restrictions with respect to this document. Code Components 48 extracted from this document must include Simplified BSD License text 49 as described in Section 4.e of the Trust Legal Provisions and are 50 provided without warranty as described in the Simplified BSD License. 52 Table of Contents 54 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 55 1.1. Alternative Method to Monitor Loc-RIB . . . . . . . . . . 4 56 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 6 57 3. Definitions . . . . . . . . . . . . . . . . . . . . . . . . . 6 58 4. Per-Peer Header . . . . . . . . . . . . . . . . . . . . . . . 7 59 4.1. Peer Type . . . . . . . . . . . . . . . . . . . . . . . . 7 60 4.2. Peer Flags . . . . . . . . . . . . . . . . . . . . . . . 7 61 5. Loc-RIB Monitoring . . . . . . . . . . . . . . . . . . . . . 8 62 5.1. Per-Peer Header . . . . . . . . . . . . . . . . . . . . . 8 63 5.2. Peer Up Notification . . . . . . . . . . . . . . . . . . 9 64 5.2.1. Peer Up Information . . . . . . . . . . . . . . . . . 9 65 5.3. Peer Down Notification . . . . . . . . . . . . . . . . . 10 66 5.4. Route Monitoring . . . . . . . . . . . . . . . . . . . . 10 67 5.4.1. ASN Encoding . . . . . . . . . . . . . . . . . . . . 10 68 5.4.2. Granularity . . . . . . . . . . . . . . . . . . . . . 10 69 5.5. Route Mirroring . . . . . . . . . . . . . . . . . . . . . 11 70 5.6. Statistics Report . . . . . . . . . . . . . . . . . . . . 11 71 6. Other Considerations . . . . . . . . . . . . . . . . . . . . 11 72 6.1. Loc-RIB Implementation . . . . . . . . . . . . . . . . . 11 73 6.1.1. Multiple Loc-RIB Peers . . . . . . . . . . . . . . . 11 74 6.1.2. Filtering Loc-RIB to BMP Receivers . . . . . . . . . 12 75 6.1.3. Changes to existing BMP sessions . . . . . . . . . . 12 76 7. Security Considerations . . . . . . . . . . . . . . . . . . . 12 77 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 12 78 8.1. BMP Peer Type . . . . . . . . . . . . . . . . . . . . . . 12 79 8.2. BMP Loc-RIB Instance Peer Flags . . . . . . . . . . . . . 12 80 8.3. Peer Up Information TLV . . . . . . . . . . . . . . . . . 13 81 8.4. Peer Down Reason code . . . . . . . . . . . . . . . . . . 13 82 9. Normative References . . . . . . . . . . . . . . . . . . . . 13 83 10. Informative References . . . . . . . . . . . . . . . . . . . 14 84 Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 14 85 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 14 87 1. Introduction 89 This document defines a mechanism to monitor the BGP Loc-RIB state of 90 remote BGP instances without the need to establish BGP peering 91 sessions. BMP [RFC7854] does not define a method to send the BGP 92 instance Loc-RIB. It does define in section 8.2 of [RFC7854] locally 93 originated routes, but these routes are defined as the routes 94 originated into BGP. For example, as defined by Section 9.4 of 95 [RFC4271]. Loc-RIB includes all selected received routes from BGP 96 peers in addition to locally originated routes. 98 Figure 1 shows the flow of received routes from one or more BGP peers 99 into the Loc-RIB. 101 +------------------+ +------------------+ 102 | Peer-A | | Peer-B | 103 /-- | | ---- | | --\ 104 | | Adj-RIB-In (Pre) | | Adj-RIB-In (Pre) | | 105 | +------------------+ +------------------+ | 106 | | | | 107 | Filters/Policy -| Filters/Policy -| | 108 | V V | 109 | +------------------+ +------------------+ | 110 | | Adj-RIB-In (Post)| | Adj-RIB-In (Post)| | 111 | +------------------+ +------------------+ | 112 | | | | 113 | Selected -| Selected -| | 114 | V V | 115 | +-----------------------------------------+ | 116 | | Loc-RIB | | 117 | +-----------------------------------------+ | 118 | | 119 | ROUTER/BGP Instance | 120 \----------------------------------------------------/ 122 Figure 1: BGP peering Adj-RIBs-In into Loc-RIB 124 The following are some use-cases for Loc-RIB access: 126 * The Adj-RIB-In for a given peer Post-Policy may contain hundreds 127 of thousands of routes, with only a handful of routes selected and 128 installed in the Loc-RIB after best-path selection. Some 129 monitoring applications, such as ones that need only to correlate 130 flow records to Loc-RIB entries, only need to collect and monitor 131 the routes that are actually selected and used. 133 Requiring the applications to collect all Adj-RIB-In Post-Policy 134 data forces the applications to receive a potentially large 135 unwanted data set and to perform the BGP decision process 136 selection, which includes having access to the interior gateway 137 protocol (IGP) next-hop metrics. While it is possible to obtain 138 the IGP topology information using BGP Link-State (BGP-LS), it 139 requires the application to implement shortest path first (SPF) 140 and possibly constrained shortest path first (CSPF) based on 141 additional policies. This is overly complex for such a simple 142 application that only needs to have access to the Loc-RIB. 144 * It is common to see frequent changes over many BGP peers, but 145 those changes do not always result in the router's Loc-RIB 146 changing. The change in the Loc-RIB can have a direct impact on 147 the forwarding state. It can greatly reduce time to troubleshoot 148 and resolve issues if operators have the history of Loc-RIB 149 changes. For example, a performance issue might have been seen 150 for only a duration of 5 minutes. Post-facto troubleshooting this 151 issue without Loc-RIB history hides any decision based routing 152 changes that might have happened during those five minutes. 154 * Operators may wish to validate the impact of policies applied to 155 Adj-RIB-In by analyzing the final decision made by the router when 156 installing into the Loc-RIB. For example, in order to validate if 157 multi-path prefixes are installed as expected for all advertising 158 peers, the Adj-RIB-In Post-Policy and Loc-RIB needs to be 159 compared. This is only possible if the Loc-RIB is available. 160 Monitoring the Adj-RIB-In for this router from another router to 161 derive the Loc-RIB is likely to not show same installed prefixes. 162 For example, the received Adj-RIB-In will be different if ADD-PATH 163 [RFC7911] is not enabled or if maximum supported number of equal 164 paths is different between Loc-RIB and advertised routes. 166 This document adds Loc-RIB to the BGP Monitoring Protocol and 167 replaces Section 8.2 of [RFC7854] Locally Originated Routes. 169 1.1. Alternative Method to Monitor Loc-RIB 171 Loc-RIB is used to build Adj-RIB-Out when advertising routes to a 172 peer. It is therefore possible to derive the Loc-RIB of a router by 173 monitoring the Adj-RIB-In Pre-Policy from another router. This 174 becomes overly complex and error prone when considering the number of 175 peers being monitored per router. 177 /------------------------------------------------------\ 178 | ROUTER1 BGP Instance | 179 | | 180 | +--------------------------------------------+ | 181 | | Loc-RIB | | 182 | +--------------------------------------------+ | 183 | | | | 184 | +------------------+ +------------------+ | 185 | | Peer-ROUTER2 | | Peer-ROUTER3 | | 186 | | Adj-RIB-Out (Pre)| | Adj-RIB-Out (Pre)| | 187 | +------------------+ +------------------+ | 188 | Filters/Policy -| Filters/Policy -| | 189 | V V | 190 | +-------------------+ +-------------------+ | 191 | | Adj-RIB-Out (Post)| | Adj-RIB-Out (Post)| | 192 | +-------------------+ +-------------------+ | 193 | | | | 194 \------------- | ------------------------ | -----------/ 195 BGP | BGP | 196 Peer | Peer | 197 +------------------+ +------------------+ 198 | Peer-ROUTER1 | | Peer-ROUTER1 | 199 /--| |--\ /--| | --\ 200 | | Adj-RIB-In (Pre) | | | | Adj-RIB-In (Pre) | | 201 | +------------------+ | | +------------------+ | 202 | | | | 203 | ROUTER2/BGP Instance | | ROUTER3/BGP Instance | 204 \------------------------/ \-------------------------/ 205 | | 206 v v 207 ROUTER2 BMP Feed ROUTER3 BMP Feed 209 Figure 2: Alternative method to monitor Loc-RIB 211 The setup needed to monitor the Loc-RIB of a router requires another 212 router with a peering session to the target router that is to be 213 monitored. As shown in Figure 2, the target router Loc-RIB is 214 advertised via Adj-RIB-Out to the BMP router over a standard BGP 215 peering session. The BMP router then forwards Adj-RIB-In Pre-Policy 216 to the BMP receiver. 218 BMP lacking access to Loc-RIB introduces the need for additional 219 resources: 221 * Requires at least two routers when only one router was to be 222 monitored. 224 * Requires additional BGP peering to collect the received updates 225 when peering may have not even been required in the first place. 226 For example, virtual routing and forwarding (VRF) tables with no 227 peers, redistributed BGP-LS with no peers, and segment routing 228 egress peer engineering where no peers have link-state address 229 family enabled are all situations with no preexisting BGP peers. 231 Many complexities are introduced when using a received Adj-RIB-In to 232 infer a router Loc-RIB: 234 * Adj-RIB-Out received as Adj-RIB-In from another router may have a 235 policy applied that filters, generates aggregates, suppresses more 236 specific prefixes, manipulates attributes, or filters routes. Not 237 only does this invalidate the Loc-RIB view, it adds complexity 238 when multiple BMP routers may have peering sessions to the same 239 router. The BMP receiver user is left with the error-prone task 240 of identifying which peering session is the best representative of 241 the Loc-RIB. 243 * BGP peering is designed to work between administrative domains and 244 therefore does not need to include internal system level 245 information of each peering router (e.g., the system name or 246 version information). In order to derive the Loc-RIB of a router, 247 the router name or other system information is needed. The BMP 248 receiver and user are forced to do some type of correlation using 249 what information is available in the peering session (e.g., 250 peering addresses, autonomous system numbers, and BGP 251 identifiers). This leads to error-prone correlations. 253 * Correlating BGP identifiers (BGP-ID) and session addresses to a 254 router requires additional data, such as router inventory. This 255 additional data provides the BMP receiver the ability to map and 256 correlate the BGP-IDs and/or session addresses, but requires the 257 BMP receiver to somehow obtain this data outside of BMP. How this 258 data is obtained and the accuracy of the data directly affects the 259 integrity of the correlation. 261 2. Terminology 263 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 264 "SHOULD", "SHOULD NOT", "RECOMMENDED", "NOT RECOMMENDED", "MAY", and 265 "OPTIONAL" in this document are to be interpreted as described in BCP 266 14 RFC 2119 [RFC2119] RFC 8174 [RFC8174] when, and only when, they 267 appear in all capitals, as shown here. 269 3. Definitions 270 * BGP Instance: refers to an instance of BGP-4 [RFC4271] and 271 considerations in section 8.1 of [RFC7854] do apply to it. 273 * Adj-RIB-In: As defined in [RFC4271], "The Adj-RIBs-In contains 274 unprocessed routing information that has been advertised to the 275 local BGP speaker by its peers." This is also referred to as the 276 pre-policy Adj-RIB-In in this document. 278 * Adj-RIB-Out: As defined in [RFC4271], "The Adj-RIBs-Out contains 279 the routes for advertisement to specific peers by means of the 280 local speaker's UPDATE messages." 282 * Loc-RIB: As defined in section 9.4 of [RFC4271], "The Loc-RIB 283 contains the routes that have been selected by the local BGP 284 speaker's Decision Process." Note that the Loc-RIB state as 285 monitored through BMP might also contain routes imported from 286 other routing protocols such as an IGP, or local static routes. 288 * Pre-Policy Adj-RIB-Out: The result before applying the outbound 289 policy to an Adj-RIB-Out. This normally represents a similar view 290 of the Loc-RIB but may contain additional routes based on BGP 291 peering configuration. 293 * Post-Policy Adj-RIB-Out: The result of applying outbound policy to 294 an Adj-RIB-Out. This MUST be what is actually sent to the peer. 296 4. Per-Peer Header 298 4.1. Peer Type 300 A new peer type is defined for Loc-RIB to distinguish that it 301 represents the router Loc-RIB, which may have a route distinguisher 302 (RD). Section 4.2 of [RFC7854] defines a Local Instance Peer type, 303 which is for the case of non-RD peers that have an instance 304 identifier. 306 This document defines the following new peer type: 308 * Peer Type = 3: Loc-RIB Instance Peer 310 4.2. Peer Flags 312 If locally sourced routes are communicated using BMP, they MUST be 313 conveyed using the Loc-RIB instance peer type. 315 The per-peer header flags for Loc-RIB Instance Peer type are defined 316 as follows: 318 0 1 2 3 4 5 6 7 319 +-+-+-+-+-+-+-+-+ 320 |F| | | | | | | | 321 +-+-+-+-+-+-+-+-+ 323 * The F flag indicates that the Loc-RIB is filtered. This MUST be 324 set when a filter is applied to Loc-RIB routes sent to the BMP 325 collector. 327 The unused bits are reserved for future use. They MUST be 328 transmitted as 0 and their values MUST be ignored on receipt. 330 5. Loc-RIB Monitoring 332 The Loc-RIB contains all routes selected by the BGP Decision Process 333 as described in section 9.1 of [RFC4271]. These routes include those 334 learned from BGP peers via its Adj-RIBs-In Post-Policy, as well as 335 routes learned by other means as per section 9.4 of [RFC4271]. 336 Examples of these include redistribution of routes from other 337 protocols into BGP or otherwise locally originated (i.e., aggregate 338 routes). 340 As described in Section 6.1.2, a subset of Loc-RIB routes MAY be sent 341 to a BMP collector by setting the F flag. 343 5.1. Per-Peer Header 345 All peer messages that include a per-peer header as defined in 346 section 4.2 of [RFC7854] MUST use the following values: 348 * Peer Type: Set to 3 to indicate Loc-RIB Instance Peer. 350 * Peer Distinguisher: Zero filled if the Loc-RIB represents the 351 global instance. Otherwise set to the route distinguisher or 352 unique locally defined value of the particular instance the Loc- 353 RIB belongs to. 355 * Peer Address: Zero-filled. Remote peer address is not applicable. 356 The V flag is not applicable with Loc-RIB Instance peer type 357 considering addresses are zero-filed. 359 * Peer AS: Set to the primary router BGP autonomous system number 360 (ASN). 362 * Peer BGP ID: Set to the BGP instance global or RD (e.g., VRF) 363 specific router-id section 1.1 of [RFC7854]. 365 * Timestamp: The time when the encapsulated routes were installed in 366 the Loc-RIB, expressed in seconds and microseconds since midnight 367 (zero hour), January 1, 1970 (UTC). If zero, the time is 368 unavailable. Precision of the timestamp is implementation- 369 dependent. 371 5.2. Peer Up Notification 373 Peer Up notifications follow section 4.10 of [RFC7854] with the 374 following clarifications: 376 * Local Address: Zero-filled, local address is not applicable. 378 * Local Port: Set to 0, local port is not applicable. 380 * Remote Port: Set to 0, remote port is not applicable. 382 * Sent OPEN Message: This is a fabricated BGP OPEN message. 383 Capabilities MUST include the 4-octet ASN and all necessary 384 capabilities to represent the Loc-RIB route monitoring messages. 385 Only include capabilities if they will be used for Loc-RIB 386 monitoring messages. For example, if ADD-PATH is enabled for IPv6 387 and Loc-RIB contains additional paths, the ADD-PATH capability 388 should be included for IPv6. In the case of ADD-PATH, the 389 capability intent of advertise, receive or both can be ignored 390 since the presence of the capability indicates enough that add- 391 paths will be used for IPv6. 393 * Received OPEN Message: Repeat of the same Sent Open Message. The 394 duplication allows the BMP receiver to parse the expected received 395 OPEN message as defined in section 4.10 of [RFC7854]. 397 5.2.1. Peer Up Information 399 The following Peer Up information TLV type is added: 401 * Type = 3: VRF/Table Name. The Information field contains a UTF-8 402 string whose value MUST be equal to the value of the VRF or table 403 name (e.g., RD instance name) being conveyed. The string size 404 MUST be within the range of 1 to 255 bytes. 406 The VRF/Table Name TLV is optionally included to support 407 implementations that may not have defined a name. If a name is 408 configured, it MUST be included. The default value of "global" 409 MUST be used for the default Loc-RIB instance with a zero-filled 410 distinguisher. If the TLV is included, then it MUST also be 411 included in the Peer Down notification. 413 Multiple TLVs of the same type can be repeated as part of the same 414 message, for example to convey a filtered view of a VRF. A BMP 415 receiver should append multiple TLVs of the same type to a set in 416 order to support alternate or additional names for the same peer. If 417 multiple strings are included, their ordering MUST be preserved when 418 they are reported. 420 5.3. Peer Down Notification 422 Peer Down notification MUST use reason code 6. Following the reason 423 is data in TLV format. The following Peer Down information TLV type 424 is defined: 426 * Type = 3: VRF/Table Name. The Information field contains a UTF-8 427 string whose value MUST be equal to the value of the VRF or table 428 name (e.g., RD instance name) being conveyed. The string size 429 MUST be within the range of 1 to 255 bytes. The VRF/Table Name 430 informational TLV MUST be included if it was in the Peer Up. 432 5.4. Route Monitoring 434 Route Monitoring messages are used for initial synchronization of the 435 Loc-RIB. They are also used to convey incremental Loc-RIB changes. 437 As defined in section 4.6 of [RFC7854], "Following the common BMP 438 header and per-peer header is a BGP Update PDU." 440 5.4.1. ASN Encoding 442 Loc-RIB route monitor messages MUST use 4-byte ASN encoding as 443 indicated in Peer Up sent OPEN message (Section 5.2) capability. 445 5.4.2. Granularity 447 State compression and throttling SHOULD be used by a BMP sender to 448 reduce the amount of route monitoring messages that are transmitted 449 to BMP receivers. With state compression, only the final resultant 450 updates are sent. 452 For example, prefix 192.0.2.0/24 is updated in the Loc-RIB 5 times 453 within 1 second. State compression of BMP route monitor messages 454 results in only the final change being transmitted. The other 4 455 changes are suppressed because they fall within the compression 456 interval. If no compression was being used, all 5 updates would have 457 been transmitted. 459 A BMP receiver should expect that Loc-RIB route monitoring 460 granularity can be different by BMP sender implementation. 462 5.5. Route Mirroring 464 Section 4.7 of [RFC7854], defines Route Mirroring for verbatim 465 duplication of messages received. This is not applicable to Loc-RIB 466 as PDUs are originated by the router. Any received Route Mirroring 467 messages SHOULD be ignored. 469 5.6. Statistics Report 471 Not all Stat Types are relevant to Loc-RIB. The Stat Types that are 472 relevant are listed below: 474 * Stat Type = 8: (64-bit Gauge) Number of routes in Loc-RIB. 476 * Stat Type = 10: Number of routes in per-AFI/SAFI Loc-RIB. The 477 value is structured as: 2-byte AFI, 1-byte SAFI, followed by a 64- 478 bit Gauge. 480 6. Other Considerations 482 6.1. Loc-RIB Implementation 484 There are several methods for a BGP speaker to implement Loc-RIB 485 efficiently. In all methods, the implementation emulates a peer with 486 Peer Up and Down messages to convey capabilities as well as Route 487 Monitor messages to convey Loc-RIB. In this sense, the peer that 488 conveys the Loc-RIB is a locally emulated peer. 490 6.1.1. Multiple Loc-RIB Peers 492 There MUST be at least one emulated peer for each Loc-RIB instance, 493 such as with VRFs. The BMP receiver identifies the Loc-RIB by the 494 peer header distinguisher and BGP ID. The BMP receiver uses the VRF/ 495 Table Name from the Peer Up information to associate a name to the 496 Loc-RIB. 498 In some implementations, it might be required to have more than one 499 emulated peer for Loc-RIB to convey different address families for 500 the same Loc-RIB. In this case, the peer distinguisher and BGP ID 501 should be the same since they represent the same Loc-RIB instance. 502 Each emulated peer instance MUST send a Peer Up with the OPEN message 503 indicating the address family capabilities. A BMP receiver MUST 504 process these capabilities to know which peer belongs to which 505 address family. 507 6.1.2. Filtering Loc-RIB to BMP Receivers 509 There maybe be use-cases where BMP receivers should only receive 510 specific routes from Loc-RIB. For example, IPv4 unicast routes may 511 include internal BGP (IBGP), external BGP (EBGP), and IGP but only 512 routes from EBGP should be sent to the BMP receiver. Alternatively, 513 it may be that only IBGP and EBGP that should be sent and IGP 514 redistributed routes should be excluded. In these cases where the 515 Loc-RIB is filtered, the F flag is set to 1 to indicate to the BMP 516 receiver that the Loc-RIB is filtered. If multiple filters are 517 associated to the same Loc-RIB, a Table Name MUST be used in order to 518 allow a BMP receiver to make the right associations. 520 6.1.3. Changes to existing BMP sessions 522 In case of any change that results in the alteration of behavior of 523 an existing BMP session, ie. changes to filtering and table names, 524 the session MUST be bounced with a Peer Down/Peer Up sequence. 526 7. Security Considerations 528 The same considerations as in section 11 of [RFC7854] apply to this 529 document. Implementations of this protocol SHOULD require that 530 sessions are only established with authorized and trusted monitoring 531 devices. It is also believed that this document does not add any 532 additional security considerations. 534 8. IANA Considerations 536 This document requests that IANA assign the following new parameters 537 to the BMP parameters name space (https://www.iana.org/assignments/ 538 bmp-parameters/bmp-parameters.xhtml). 540 8.1. BMP Peer Type 542 This document defines a new peer type (Section 4.1): 544 * Peer Type = 3: Loc-RIB Instance Peer 546 8.2. BMP Loc-RIB Instance Peer Flags 548 This document requests IANA to rename "BMP Peer Flags" to "BMP Peer 549 Flags for Peer Types 0 through 2" and create a new registry named 550 "BMP Peer Flags for Loc-RIB Instance Peer Type 3" This document 551 defines that peer flags are specific to the Loc-RIB instance peer 552 type. As defined in (Section 4.2): 554 * Flag 0: The F flag indicates that the Loc-RIB is filtered. This 555 indicates that the Loc-RIB does not represent the complete routing 556 table. 558 Flags 0 through 3 and 5 through 7 are unassigned. The registration 559 procedure for the registry is "Standards Action". 561 8.3. Peer Up Information TLV 563 This document requests that IANA rename "BMP Initiation Message TLVs" 564 registry to "BMP Initiation and Peer Up Information TLVs." section 565 4.4 of [RFC7854] defines that both Initiation and Peer Up share the 566 same information TLVs. This document defines the following new BMP 567 Peer Up information TLV type (Section 5.2.1): 569 * Type = 3: VRF/Table Name. The Information field contains a UTF-8 570 string whose value MUST be equal to the value of the VRF or table 571 name (e.g., RD instance name) being conveyed. The string size 572 MUST be within the range of 1 to 255 bytes. 574 8.4. Peer Down Reason code 576 This document defines the following new BMP Peer Down reason code 577 (Section 5.3): 579 * Type = 6: Local system closed, TLV data follows. 581 9. Normative References 583 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 584 Requirement Levels", BCP 14, RFC 2119, 585 DOI 10.17487/RFC2119, March 1997, 586 . 588 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 589 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 590 DOI 10.17487/RFC4271, January 2006, 591 . 593 [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an 594 IANA Considerations Section in RFCs", RFC 5226, 595 DOI 10.17487/RFC5226, May 2008, 596 . 598 [RFC7854] Scudder, J., Ed., Fernando, R., and S. Stuart, "BGP 599 Monitoring Protocol (BMP)", RFC 7854, 600 DOI 10.17487/RFC7854, June 2016, 601 . 603 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 604 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 605 May 2017, . 607 10. Informative References 609 [RFC7911] Walton, D., Retana, A., Chen, E., and J. Scudder, 610 "Advertisement of Multiple Paths in BGP", RFC 7911, 611 DOI 10.17487/RFC7911, July 2016, 612 . 614 Acknowledgements 616 The authors would like to thank John Scudder, Jeff Haas and Mukul 617 Srivastava for their valuable input. 619 Authors' Addresses 621 Tim Evens 622 Cisco Systems 623 2901 Third Avenue, Suite 600 624 Seattle, WA 98121 625 United States of America 627 Email: tievens@cisco.com 629 Serpil Bayraktar 630 Cisco Systems 631 3700 Cisco Way 632 San Jose, CA 95134 633 United States of America 635 Email: serpil@cisco.com 637 Manish Bhardwaj 638 Cisco Systems 639 3700 Cisco Way 640 San Jose, CA 95134 641 United States of America 643 Email: manbhard@cisco.com 645 Paolo Lucente 646 NTT Communications 647 Siriusdreef 70-72 648 2132 Hoofddorp 649 Netherlands 651 Email: paolo@ntt.net