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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 IDR Working Group S. Hares 3 Internet-Draft Huawei 4 Obsoletes: 5575 (if approved) July 8, 2016 5 Updates: 7674 (if approved) 6 Intended status: Standards Track 7 Expires: January 9, 2017 9 Dissemination of Flow Specification Rules 10 draft-hares-idr-rfc5575bis-01.txt 12 Abstract 14 This document updates RFC5575 which defines a Border Gateway Protocol 15 Network Layer Reachability Information (BGP NLRI) encoding format 16 that can be used to distribute traffic flow specifications. This 17 allows the routing system to propagate information regarding more 18 specific components of the traffic aggregate defined by an IP 19 destination prefix (IPv4, IPv6), MPLS addresses, L2VPN addresses, and 20 NV03 encapsulation of IP addresses. The information is carried via 21 the BGP, thereby reusing protocol algorithms, operational experience, 22 and administrative processes such as inter-provider peering 23 agreements. 25 There are three applications of that encoding format: 1) automation 26 of inter-domain coordination of traffic filtering, such as what is 27 required in order to mitigate (distributed) denial-of-service 28 attacks; 2) enable traffic filtering in the context of a BGP/MPLS VPN 29 service, and 3) aid centralized control of traffic in a SDN or NFV 30 context. Some of deployments of these three applications can be 31 handled by the strict ordering of the BGP NLRI traffic flow filters, 32 and the strict actions encoded in the Extended Community Flow 33 Specification actions. Other deployments (especially SDN/NFV) need 34 to be able to allow the user to order the flow specification. 35 Another BGP Flow Specification (version 2) is being defined for user- 36 ordered filters, and user-ordered actions encoded in Wide 37 Communities. 39 This document provides the definition of a BGP NLRI which carries 40 traffic flow specification filters, and Extended Community values 41 which encode the actions a routing system can take if a packet 42 matches the traffic flow filters. The specification requires that 43 the BGP Flow Specification traffic filters follows a string ordering, 44 and that the BGP Flow Specification Extended Communities actions are 45 processed in a defined order. This BGP Flow Specification is denoted 46 as BGP Flow Specification version 1. 48 There are three applications of that encoding format: 1) automation 49 of inter-domain coordination of traffic filtering, such as what is 50 required in order to mitigate (distributed) denial-of-service 51 attacks; 2) enable traffic filtering in the context of a BGP/MPLS VPN 52 service, and 3) aid centralized control of traffic in a SDN or NFV 53 context. Some of deployments of these three applications can be 54 handled by the strict ordering of the BGP NLRI traffic flow filters, 55 and the strict actions encoded in the Extended Community Flow 56 Specification actions. Other deployments (especially SDN/NFV) need 57 to be able to allow the user to order the flow specification. 58 Another BGP Flow Specification (version 2) is being defined for user- 59 ordered filters, and user-ordered actions encoded in Wide 60 Communities. 62 Status of This Memo 64 This Internet-Draft is submitted in full conformance with the 65 provisions of BCP 78 and BCP 79. 67 Internet-Drafts are working documents of the Internet Engineering 68 Task Force (IETF). Note that other groups may also distribute 69 working documents as Internet-Drafts. The list of current Internet- 70 Drafts is at http://datatracker.ietf.org/drafts/current/. 72 Internet-Drafts are draft documents valid for a maximum of six months 73 and may be updated, replaced, or obsoleted by other documents at any 74 time. It is inappropriate to use Internet-Drafts as reference 75 material or to cite them other than as "work in progress." 77 This Internet-Draft will expire on January 9, 2017. 79 Copyright Notice 81 Copyright (c) 2016 IETF Trust and the persons identified as the 82 document authors. All rights reserved. 84 This document is subject to BCP 78 and the IETF Trust's Legal 85 Provisions Relating to IETF Documents 86 (http://trustee.ietf.org/license-info) in effect on the date of 87 publication of this document. Please review these documents 88 carefully, as they describe your rights and restrictions with respect 89 to this document. Code Components extracted from this document must 90 include Simplified BSD License text as described in Section 4.e of 91 the Trust Legal Provisions and are provided without warranty as 92 described in the Simplified BSD License. 94 Table of Contents 96 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 4 97 2. Definitions of Terms Used in This Memo . . . . . . . . . . . 6 98 3. Flow Specifications . . . . . . . . . . . . . . . . . . . . . 6 99 4. Traffic Filtering . . . . . . . . . . . . . . . . . . . . . . 7 100 4.1. Support for other AFIs . . . . . . . . . . . . . . . . . 8 101 5. Dissemination of IPv4 FLow Specification Information . . . . 8 102 5.1. Length Encoding . . . . . . . . . . . . . . . . . . . . . 9 103 5.2. NLRI Value Encoding . . . . . . . . . . . . . . . . . . . 9 104 5.2.1. Type 1 - Destination Prefix . . . . . . . . . . . . . 13 105 5.2.2. Type 2 - Source Prefix . . . . . . . . . . . . . . . 13 106 5.2.3. Type 3 - Source Prefix . . . . . . . . . . . . . . . 13 107 5.2.4. Type 4 - Port . . . . . . . . . . . . . . . . . . . . 14 108 5.2.5. Type 5 - Destination Port . . . . . . . . . . . . . . 14 109 5.2.6. Type 6 - Destination Port . . . . . . . . . . . . . . 14 110 5.2.7. Type 7 - ICMP type . . . . . . . . . . . . . . . . . 14 111 5.2.8. Type 8 - ICMP code . . . . . . . . . . . . . . . . . 15 112 5.2.9. Type 9 - ICMP code . . . . . . . . . . . . . . . . . 15 113 5.2.10. Type 10 - Packet length . . . . . . . . . . . . . . . 15 114 5.2.11. Type 11 - DSCP (Diffserv Code Point) . . . . . . . . 16 115 5.2.12. Type 12 - Fragment . . . . . . . . . . . . . . . . . 16 116 5.2.13. Examples of Encodings . . . . . . . . . . . . . . . . 16 117 5.3. Ordering of Traffic Filtering Rules . . . . . . . . . . . 17 118 5.4. Validation Procedure . . . . . . . . . . . . . . . . . . 19 119 6. Traffic Filtering Actions . . . . . . . . . . . . . . . . . . 20 120 6.1. Traffic Rate in bytes (sub-type 0x06) . . . . . . . . . . 21 121 6.2. Traffic-action (sub-type 0x07) . . . . . . . . . . . . . 22 122 6.3. IP Redirect (sub-type 0x08) . . . . . . . . . . . . . . . 22 123 6.4. Traffic Marking (sub-type 0x09) . . . . . . . . . . . . . 23 124 6.5. Rules on Traffic Action interference . . . . . . . . . . 23 125 7. Dissemination of Traffic Filtering in BGP/MPLS VPN Networks . 23 126 7.1. Validation Procedures for BGP/MPLS VPNs . . . . . . . . . 24 127 7.2. Traffic Actions Rules . . . . . . . . . . . . . . . . . . 24 128 8. Limitations of Previous Traffic Filtering Efforts . . . . . . 24 129 8.1. Limitations in Previous DDOS Traffic Filtering Efforts . 24 130 8.2. Limitations in Previous BGP/MPLS Traffic Monitoring . . . 25 131 8.3. Limitations in BGP Flow Specification for SDN/NFV 132 Applications . . . . . . . . . . . . . . . . . . . . . . 26 133 9. Traffic Monitoring . . . . . . . . . . . . . . . . . . . . . 26 134 10. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 26 135 10.1. AFI/SAFI Definitions . . . . . . . . . . . . . . . . . . 26 136 10.2. Flow Component definitions . . . . . . . . . . . . . . . 26 137 10.3. Extended Community Flow Specification Actions . . . . . 28 138 11. Security Considerations . . . . . . . . . . . . . . . . . . . 28 139 12. Original RFC5575 authors . . . . . . . . . . . . . . . . . . 29 140 13. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 29 141 14. References . . . . . . . . . . . . . . . . . . . . . . . . . 29 142 14.1. Normative References . . . . . . . . . . . . . . . . . . 29 143 14.2. Informative References . . . . . . . . . . . . . . . . . 31 144 Author's Address . . . . . . . . . . . . . . . . . . . . . . . . 33 146 1. Introduction 148 Modern IP routers contain both the capability to forward traffic 149 according to IP prefixes as well as to classify, shape, rate limit, 150 filter, or redirect packets based on administratively defined 151 policies. 153 These traffic policy mechanisms allow the router to define match 154 rules that operate on multiple fields of the packet header. Actions 155 such as the ones described above can be associated with each rule. 157 The n-tuple consisting of the matching criteria defines an aggregate 158 traffic flow specification. The matching criteria can include 159 elements such as source and destination address prefixes, IP 160 protocol, and transport protocol port numbers. 162 This document defines a general procedure to encode flow 163 specification rules for aggregated traffic flows so that they can be 164 distributed as a BGP [RFC5575] NLRI. Additionally, we define the 165 required mechanisms to utilize this definition to the problem of 166 immediate concern to the authors: intra- and inter-provider 167 distribution of traffic filtering rules to filter (distributed) 168 denial-of-service (DoS) attacks. 170 By expanding routing information with flow specifications, the 171 routing system can take advantage of the ACL (Access Control List) or 172 firewall capabilities in the router's forwarding path. Flow 173 specifications can be seen as more specific routing entries to a 174 unicast prefix and are expected to depend upon the existing unicast 175 data information. 177 A flow specification received from an external autonomous system will 178 need to be validated against unicast routing before being accepted. 179 If the aggregate traffic flow defined by the unicast destination 180 prefix is forwarded to a given BGP peer, then the local system can 181 safely install more specific flow rules that may result in different 182 forwarding behavior, as requested by this system. 184 The key technology components required to address the class of 185 problems targeted by this document are: 187 1. Efficient point-to-multipoint distribution of control plane 188 information. 190 2. Inter-domain capabilities and routing policy support. 192 3. Tight integration with unicast routing, for verification 193 purposes. 195 Items 1 and 2 have already been addressed using BGP for other types 196 of control plane information. Close integration with BGP also makes 197 it feasible to specify a mechanism to automatically verify flow 198 information against unicast routing. These factors are behind the 199 choice of BGP as the carrier of flow specification information. 201 As with previous extensions to BGP, this specification makes it 202 possible to add additional information to Internet routers. These 203 are limited in terms of the maximum number of data elements they can 204 hold as well as the number of events they are able to process in a 205 given unit of time. The authors believe that, as with previous 206 extensions, service providers will be careful to keep information 207 levels below the maximum capacity of their devices. 209 In many deployments of BGP Flow Specification, the flow specification 210 information has replace existing host length route advertisements. 212 Experience with previous BGP extensions has also shown that the 213 maximum capacity of BGP speakers has been gradually increased 214 according to expected loads. Taking into account Internet unicast 215 routing as well as additional applications as they gain popularity. 217 From an operational perspective, the utilization of BGP as the 218 carrier for this information allows a network service provider to 219 reuse both internal route distribution infrastructure (e.g., route 220 reflector or confederation design) and existing external 221 relationships (e.g., inter-domain BGP sessions to a customer 222 network). 224 While it is certainly possible to address this problem using other 225 mechanisms, this solution has been utilized in deployments because of 226 the substantial advantage of being an incremental addition to already 227 deployed mechanisms. 229 In current deployments, the information distributed by the flow-spec 230 extension is originated both manually as well as automatically. The 231 latter by systems that are able to detect malicious flows. When 232 automated systems are used, care should be taken to ensure their 233 correctness as well as to limit the number and advertisement rate of 234 flow routes. 236 This specification defines required protocol extensions to address 237 most common applications of IPv4 unicast and VPNv4 unicast filtering. 239 The same mechanism can be reused and new match criteria added to 240 address similar filtering needs for other BGP address families such 241 as: 243 o IPv6 [I-D.ietf-idr-flow-spec-v6], 245 o MAC address for L2VPN [I-D.ietf-idr-flowspec-l2vpn], 247 o NV03 encapsulation [I-D.ietf-idr-flowspec-nvo3] and, 249 o MPLS ([I-D.ietf-idr-flowspec-mpls-match], 250 [I-D.ietf-idr-bgp-flowspec-label]). 252 These additions to BGP Flow Specification IPv4 are included in a 253 separate documents to allow implementers the choice of implementing 254 portions of the BGP Flow specification. 256 2. Definitions of Terms Used in This Memo 258 NLRI - Network Layer Reachability Information. 260 RIB - Routing Information Base. 262 Loc-RIB - Local RIB. 264 AS - Autonomous System number. 266 VRF - Virtual Routing and Forwarding instance. 268 PE - Provider Edge router 270 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 271 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 272 document are to be interpreted as described in [RFC2119] 274 3. Flow Specifications 276 A flow specification is an n-tuple consisting of several matching 277 criteria that can be applied to IP traffic. A given IP packet is 278 said to match the defined flow if it matches all the specified 279 criteria. 281 A given flow may be associated with a set of attributes, depending on 282 the particular application; such attributes may or may not include 283 reachability information (i.e., NEXT_HOP). Well-known or AS-specific 284 community attributes can be used to encode a set of predetermined 285 actions. 287 A particular application is identified by a specific (Address Family 288 Identifier, Subsequent Address Family Identifier (AFI, SAFI)) pair 289 [RFC4760] and corresponds to a distinct set of RIBs. Those RIBs 290 should be treated independently from each other in order to assure 291 non-interference between distinct applications. 293 BGP itself treats the NLRI as an opaque key to an entry in its 294 databases. Entries that are placed in the Loc-RIB are then 295 associated with a given set of semantics, which is application 296 dependent. This is consistent with existing BGP applications. For 297 instance, IP unicast routing (AFI=1, SAFI=1) and IP multicast 298 reverse-path information (AFI=1, SAFI=2) are handled by BGP without 299 any particular semantics being associated with them until installed 300 in the Loc-RIB. 302 Standard BGP policy mechanisms, such as UPDATE filtering by NLRI 303 prefix and community matching, SHOULD apply to the Flow specification 304 defined NLRI-type. Network operators can also control propagation of 305 such routing updates by enabling or disabling the exchange of a 306 particular (AFI, SAFI) pair on a given BGP peering session. 308 4. Traffic Filtering 310 Traffic filtering policies have been traditionally considered to be 311 relatively static. Limitations of the static mechanisms caused this 312 mechanism to be designed for the three new applications of traffic 313 filtering (prevention of traffic-based, denial-of-service (DOS) 314 attacks, traffic filtering in the context of BGP/MPLS VPN service, 315 and centralized traffic control for SDN/NFV networks) requires 316 coordination among service providers and/or coordination among the AS 317 within a service provider. Section 8 has details on the limitation 318 of previous mechanisms and why BGP Flow Specification version 1 319 provides a solution for to prevent DOS and aid BGP/MPLS VPN filtering 320 rules. 322 This flow specification NLRI defined above to convey information 323 about traffic filtering rules for traffic that should be discarded or 324 handled in manner specified by a set of pre-defined actions (which 325 are defined in BGP Extended Communities). This mechanism is 326 primarily designed to allow an upstream autonomous system to perform 327 inbound filtering in their ingress routers of traffic that a given 328 downstream AS wishes to drop. 330 In order to achieve this goal, this draft specifies two application 331 specific NLRI identifiers that provide traffic filters, and a set of 332 actions encoding in BGP Extended Communities. The two application 333 specific NLRI identifiers are: 335 o IPv4 flow specification identifier (AFI=1, SAFI=133) along with 336 specific semantic rules for IPv4 routes, and 338 o BGP NLRI type (AFI=1, SAFI=134) value, which can be used to 339 propagate traffic filtering information in a BGP/MPLS VPN 340 environment. 342 Distribution of the IPv4 Flow specification is described in section 343 6, and distibution of BGP/MPLS traffic flow specification is 344 described in section 8. The traffic filtering actions are described 345 in section 7. 347 4.1. Support for other AFIs 349 Other documents shown in table 5 provide the application identifiers 350 for IPv6, L2VPN, NVO3 and MPLS. However, to provide backward 351 compatiblity with [RFC5575] documents adhering to this specification 352 do not need to support IPv6, L2VPN, NV03, and MPLS AFI/SAFIs. 354 Table 5 - AFI/SAFI values vs. application 355 +---+----+-----------+-----------------------------------+---+ 356 |AFI|SAFI|Application| Document |Req| 357 +---+----+-----------+-----------------------------------+---+ 358 | 1| 133| DDOS | this document |Yes| 359 | 1| 134| BGP/MPLS | this document | No| 360 +---+----------------+-----------------------------------+---+ 361 | 2| 133| DDOS |draft-ietf-idr-flow-spec-v6 | No| 362 | 2| 134| BGP/MPLS |draft-ietf-idr-flow-spec-v6 | No| 363 +---+----+-----------+-----------------------------------+---+ 364 | 25| 133| DDOS |draft-ietf-idr-flowspec-l2vpn | No| 365 | 25| 134| BGP/MPLS |draft-ietf-idr-flowspec-l2vpn | No| 366 +---+----+-----------+-----------------------------------+---+ 367 |TBD| 133| DDOS |draft-ietf-idr-flowspec-mpls-label | No| 368 |TBD| 134| BGP/MPLS |draft-ietf-idr-flowspec-mpls-label | No| 369 +---+----+-----------+-----------------------------------+---+ 370 |TBD| 133| DDOS |draft-ietf-idr-flowspec-nv03 | No| 371 |TBD| 134| BGP/MPLS |draft-ietf-idr-flowspec-nv03 | No| 372 +---+----+-----------+-----------------------------------+---+ 374 5. Dissemination of IPv4 FLow Specification Information 376 We define a "Flow Specification" NLRI type that may include several 377 components such as destination prefix, source prefix, protocol, 378 ports, and others (see Tables 1-4 below). This NLRI is treated as an 379 opaque bit string prefix by BGP. Each bit string identifies a key to 380 a database entry with which a set of attributes can be associated. 382 This NLRI information is encoded using MP_REACH_NLRI and 383 MP_UNREACH_NLRI attributes as defined in [RFC4760]. Whenever the 384 corresponding application does not require Next-Hop information, this 385 shall be encoded as a 0-octet length Next Hop in the MP_REACH_NLRI 386 attribute and ignored on receipt. 388 The NLRI field of the MP_REACH_NLRI and MP_UNREACH_NLRI is encoded as 389 a 1- or 2-octet NLRI length field followed by a variable-length NLRI 390 value. The NLRI length is expressed in octets. 392 +------------------------------+ 393 | length (0xnn or 0xfn nn) | 394 +------------------------------+ 395 | NLRI value (variable) | 396 +------------------------------+ 398 Figure 1: Flow-spec NLRI for IPv4 400 Implementations wishing to exchange flow specification rules MUST use 401 BGP's Capability Advertisement facility to exchange the Multiprotocol 402 Extension Capability Code (Code 1) as defined in [RFC4760]. The 403 (AFI, SAFI) pair carried in the Multiprotocol Extension Capability 404 MUST be the same as the one used to identify a particular application 405 that uses this NLRI-type. 407 5.1. Length Encoding 409 o If the NLRI length value is smaller than 240 (0xf0 hex), the 410 length field can be encoded as a single octet. 412 o Otherwise, it is encoded as an extended-length 2-octet value in 413 which the most significant nibble of the first byte is all ones. 415 In figure 1 above, values less-than 240 are encoded using two hex 416 digits (0xnn). Values above 240 are encoded using 3 hex digits 417 (0xfnnn). The highest value that can be represented with this 418 encoding is 4095. The value 241 is encoded as 0xf0f1. 420 5.2. NLRI Value Encoding 422 The Flow specification NLRI-type consists of several optional 423 subcomponents. A specific packet is considered to match the flow 424 specification when it matches the intersection (AND) of all the 425 components present in the specification. The encoding of each of the 426 NLRI components begins with a type field as listed in Table 1-4. 427 Sections 4.2.1 to 4.2.12 contain the specific encodings for the IPv4 428 IP layer and transport layer headings. Additional filters encodiings 429 for IPv6, L2VPN MAC Addresses, MPLS labels, and encapsulations for 430 Data Centers (e.g. NVO3) related are described in other documents 431 referenced above. 433 Flow specification components must follow strict type ordering by 434 increasing numerical order. A given component type may or may not be 435 present in the specification, but if present, it MUST precede any 436 component of higher numeric type value. 438 If a given component type within a prefix in unknown, the prefix in 439 question cannot be used for traffic filtering purposes by the 440 receiver. Since a flow specification has the semantics of a logical 441 AND of all components, if a component is FALSE, by definition it 442 cannot be applied. However, for the purposes of BGP route 443 propagation, this prefix should still be transmitted since BGP route 444 distribution is independent on NLRI semantics. 446 The 545 Defines: the destination prefix to match. Prefixes are encoded as 546 in BGP UPDATE messages, a length in bits is followed by enough 547 octets to contain the prefix information. 549 5.2.2. Type 2 - Source Prefix 551 Encoding: 553 Defines the source prefix to match. 555 5.2.3. Type 3 - Source Prefix 557 Encoding: 559 Contains a set of {operator, value} pairs that are used to match 560 the IP protocol value byte in IP packets. 562 The operator byte is encoded as: 564 0 1 2 3 4 5 6 7 565 +---+---+---+---+---+---+---+---+ 566 | e | a | len | 0 |lt |gt |eq | 567 +---+---+---+---+---+---+---+---+ 569 Numerical operator 571 e - end-of-list bit. Set in the last {op, value} pair in the 572 list. 574 a - AND bit. If unset, the previous term is logically ORed with 575 the current one. If set, the operation is a logical AND. It 576 should be unset in the first operator byte of a sequence. The AND 577 operator has higher priority than OR for the purposes of 578 evaluating logical expressions. 580 len - length of the value field for this operand is given as (1 << 581 len). 583 lt - less than comparison between data and value. 585 gt - greater than comparison between data and value. 587 eq -equality between data and value 589 The bits lt, gt, and eq can be combined to produce "less or equal", 590 "greater or equal", and inequality values 592 5.2.4. Type 4 - Port 594 Encoding: 596 Defines a list of {operation, value} pairs that matches source OR 597 destination TCP/UDP ports. This list is encoded using the numeric 598 operand format defined above. Values are encoded as 1- or 2-byte 599 quantities. 601 Port, source port, and destination port components evaluate to 602 FALSE if the IP protocol field of the packet has a value other 603 than TCP or UDP, if the packet is fragmented and this is not the 604 first fragment, or if the system in unable to locate the transport 605 header. Different implementations may or may not be able to 606 decode the transport header in the presence of IP options or 607 Encapsulating Security Payload (ESP) NULL [RFC4303] encryption. 609 5.2.5. Type 5 - Destination Port 611 Encoding: 613 Defines a list of {operation, value} pairs used to match the 614 destination port of a TCP or UDP packet. Values are encoded as 1- 615 or 2-byte quantities 617 5.2.6. Type 6 - Destination Port 619 Encoding: 621 Defines a list of {operation, value} pairs used to match the 622 source port of a TCP or UDP packet. Values are encoded as 1- or 623 2-byte quantities 625 5.2.7. Type 7 - ICMP type 627 Encoding: 629 Defines a list of {operation, value} pairs used to match the type 630 field of an ICMP packet. Values are encoded using a single byte. 632 The ICMP type and code specifiers evaluate to FALSE whenever the 633 protocol value is not ICMP. 635 5.2.8. Type 8 - ICMP code 637 Encoding: 639 Defines a list of {operation, value} pairs used to match the code 640 field of an ICMP packet. Values are encoded using a single byte. 642 5.2.9. Type 9 - ICMP code 644 Encoding: 646 Bitmask values can be encoded as a 1- or 2-byte bitmask. When a 647 single byte is specified, it matches byte 13 of the TCP header 648 [RFC0793], which contains bits 8 though 15 of the 4th 32-bit word. 649 When a 2-byte encoding is used, it matches bytes 12 and 13 of the 650 TCP header with the data offset field having a "don't care" value. 652 As with port specifiers, this component evaluates to FALSE for 653 packets that are not TCP packets. 655 This type uses the bitmask operand format, which differs from the 656 numeric operator format in the lower nibble. 658 0 1 2 3 4 5 6 7 659 +---+---+---+---+---+---+---+---+ 660 | e | a | len | 0 | 0 |not| m | 661 +---+---+---+---+---+---+---+---+ 663 Bitmask format 665 e, a, len - Most significant nibble: (end-of-list bit, AND bit, and 666 length field), as defined for in the numeric operator format. 668 not - NOT bit. If set, logical negation of operation. 670 m - Match bit. If set, this is a bitwise match operation defined 671 as "(data AND value) == value"; if unset, (data AND value) 672 evaluates to TRUE if any of the bits in the value mask are set in 673 the data 675 5.2.10. Type 10 - Packet length 677 Encoding: 679 Defines match on the total IP packet length (excluding Layer 2 but 680 including IP header). Values are encoded using 1- or 2-byte 681 quantities. 683 5.2.11. Type 11 - DSCP (Diffserv Code Point) 685 Encoding: 687 Defines a list of {operation, value} pairs used to match the 6-bit 688 DSCP field [RFC2474]. Values are encoded using a single byte, 689 where the two most significant bits are zero and the six least 690 significant bits contain the DSCP value. 692 5.2.12. Type 12 - Fragment 694 Encoding: 696 Uses bitmask operand format defined above in section 5.2.9. 698 0 1 2 3 4 5 6 7 699 +---+---+---+---+---+---+---+---+ 700 | Reserved |LF |FF |IsF|DF | 701 +---+---+---+---+---+---+---+---+ 703 Bitmask values: 705 Bit 7 - Don't fragment (DF) 707 Bit 6 - Is a fragment (IsF) 709 Bit 5 - First fragment (FF) 711 Bit 4 - Last fragment (LF) 713 5.2.13. Examples of Encodings 715 An example of a flow specification encoding for: "all packets to 716 10.0.1/24 and TCP port 25". 718 +------------------+----------+----------+ 719 | destination | proto | port | 720 +------------------+----------+----------+ 721 | 0x01 18 0a 00 01 | 03 81 06 | 04 81 19 | 722 +------------------+----------+----------+ 724 Decode for protocol: 726 +-------+----------+------------------------------+ 727 | Value | | | 728 +-------+----------+------------------------------+ 729 | 0x03 | type | | 730 | 0x81 | operator | end-of-list, value size=1, = | 731 | 0x06 | value | | 732 +-------+----------+------------------------------+ 734 An example of a flow specification encoding for: "all packets to 735 10.0.1/24 from 192/8 and port {range [137, 139] or 8080}". 737 +------------------+----------+-------------------------+ 738 | destination | source | port | 739 +------------------+----------+-------------------------+ 740 | 0x01 18 0a 01 01 | 02 08 c0 | 04 03 89 45 8b 91 1f 90 | 741 +------------------+----------+-------------------------+ 743 Decode for port: 745 +--------+----------+------------------------------+ 746 | Value | | | 747 +--------+----------+------------------------------+ 748 | 0x04 | type | | 749 | 0x03 | operator | size=1, >= | 750 | 0x89 | value | 137 | 751 | 0x45 | operator | "AND", value size=1, <= | 752 | 0x8b | value | 139 | 753 | 0x91 | operator | end-of-list, value-size=2, = | 754 | 0x1f90 | value | 8080 | 755 +--------+----------+------------------------------+ 757 This constitutes an NLRI with an NLRI length of 16 octets. 759 5.3. Ordering of Traffic Filtering Rules 761 With traffic filtering rules, more than one rule may match a 762 particular traffic flow. Thus, it is necessary to define the order 763 at which rules get matched and applied to a particular traffic flow. 764 This ordering function must be such that it must not depend on the 765 arrival order of the flow specification's rules and must be constant 766 in the network. 768 The relative order of two flow specification rules is determined by 769 comparing their respective components. The algorithm starts by 770 comparing the left-most components of the rules. If the types 771 differ, the rule with lowest numeric type value has higher precedence 772 (and thus will match before) than the rule that doesn't contain that 773 component type. If the component types are the same, then a type- 774 specific comparison is performed. 776 For IP prefix values (IP destination and source prefix) precedence is 777 given to the lowest IP value of the common prefix length; if the 778 common prefix is equal, then the most specific prefix has precedence. 780 For all other component types, unless otherwise specified, the 781 comparison is performed by comparing the component data as a binary 782 string using the memcmp() function as defined by the ISO C standard. 783 For strings of different lengths, the common prefix is compared. If 784 equal, the longest string is considered to have higher precedence 785 than the shorter one. 787 Pseudocode: 789 flow_rule_cmp (a, b) 790 { 791 comp1 = next_component(a); 792 comp2 = next_component(b); 793 while (comp1 || comp2) { 794 // component_type returns infinity on end-of-list 795 if (component_type(comp1) < component_type(comp2)) { 796 return A_HAS_PRECEDENCE; 797 } 798 if (component_type(comp1) > component_type(comp2)) { 799 return B_HAS_PRECEDENCE; 800 } 802 if (component_type(comp1) == IP_DESTINATION || IP_SOURCE) { 803 common = MIN(prefix_length(comp1), prefix_length(comp2)); 804 cmp = prefix_compare(comp1, comp2, common); 805 // not equal, lowest value has precedence 806 // equal, longest match has precedence 807 } else { 808 common = 809 MIN(component_length(comp1), component_length(comp2)); 810 cmp = memcmp(data(comp1), data(comp2), common); 811 // not equal, lowest value has precedence 812 // equal, longest string has precedence 813 } 814 } 816 return EQUAL; 817 } 818 When other AFI families are specified for BGP Flow specifications, 819 this logic MUST be expanded. Other AFI families include IPv6, MPLS, 820 L2VPN, and NV03 encapsulation. 822 5.4. Validation Procedure 824 Flow specifications received from a BGP peer and that are accepted in 825 the respective Adj-RIB-In are used as input to the route selection 826 process. Although the forwarding attributes of two routes for the 827 same flow specification prefix may be the same, BGP is still required 828 to perform its path selection algorithm in order to select the 829 correct set of attributes to advertise. 831 The first step of the BGP Route Selection procedure (Section 9.1.2 of 832 [RFC4271] is to exclude from the selection procedure routes that are 833 considered non-feasible. In the context of IP routing information, 834 this step is used to validate that the NEXT_HOP attribute of a given 835 route is resolvable. 837 The concept can be extended, in the case of flow specification NLRI, 838 to allow other validation procedures. 840 A flow specification NLRI must be validated such that it is 841 considered feasible if and only if: 843 a) The originator of the flow specification matches the originator 844 of the best-match unicast route for the destination prefix 845 embedded in the flow specification. 847 b) There are no more specific unicast routes, when compared with 848 the flow destination prefix, that have been received from a 849 different neighboring AS than the best-match unicast route, which 850 has been determined in step a). 852 By originator of a BGP route, we mean either the BGP originator path 853 attribute, as used by route reflection, or the transport address of 854 the BGP peer, if this path attribute is not present. 856 The underlying concept is that the neighboring AS that advertises the 857 best unicast route for a destination is allowed to advertise flow- 858 spec information that conveys a more or equally specific destination 859 prefix. Thus, as long as there are no more specific unicast routes, 860 received from a different neighboring AS, which would be affected by 861 that filtering rule. 863 The neighboring AS is the immediate destination of the traffic 864 described by the flow specification. If it requests these flows to 865 be dropped, that request can be honored without concern that it 866 represents a denial of service in itself. Supposedly, the traffic is 867 being dropped by the downstream autonomous system, and there is no 868 added value in carrying the traffic to it. 870 BGP implementations MUST also enforce that the AS_PATH attribute of a 871 route received via the External Border Gateway Protocol (eBGP) 872 contains the neighboring AS in the left-most position of the AS_PATH 873 attribute. While this rule is optional in the BGP specification, it 874 becomes necessary to enforce it for security reasons. 876 6. Traffic Filtering Actions 878 This specification defines a minimum set of filtering actions that it 879 standardizes as BGP extended community values [RFC4360]. This is not 880 meant to be an inclusive list of all the possible actions, but only a 881 subset that can be interpreted consistently across the network. 882 Additional actions can be defined as either requiring standards or as 883 vendor specific. 885 Implementations SHOULD provide mechanisms that map an arbitrary BGP 886 community value (normal or extended) to filtering actions that 887 require different mappings in different systems in the network. For 888 instance, providing packets with a worse-than-best-effort, per-hop 889 behavior is a functionality that is likely to be implemented 890 differently in different systems and for which no standard behavior 891 is currently known. Rather than attempting to define it here, this 892 can be accomplished by mapping a user-defined community value to 893 platform-/network-specific behavior via user configuration. 895 The default action for a traffic filtering flow specification is to 896 accept IP traffic that matches that particular rule. 898 This document defines the following extended communities values shown 899 in table X in the form 0x8xnn where nn indicates the sub-type. 901 Table 5 - Traffic Action Extended Communities 902 Defined in this document 904 +--------+-----------------------+-------------------------------------+ 905 | type | extended community | encoding | 906 +--------+-----------------------+-------------------------------------+ 907 | 0x8006 | traffic-rate in bytes | 2-byte ASN, 4-byte float | 908 | 0x8007 | traffic-action | bitmask | 909 | 0x8008 | redirect AS-2byte | 2-octet AS, 4-octet Value | 910 | 0x8108 | redirect IPv4 | 4-octet IPv4 Address, 2-octet Value | 911 | 0x8208 | redirect AS-4byte | 4-octet AS, 2-octet Value | 912 | 0x8009 | traffic-marking | DSCP value | 913 +--------+--------------------+----------------------------------------+ 915 Encodings for these extended communities are described below. 917 Some traffic action communities may interfere with each other. 918 Section x.x of this specification provides rules for handling 919 interference between specific types of traffic actions, and error 920 handling based on [RFC7606] in section. Each definition of a traffic 921 action MUST specify any interface with any other traffic actions, any 922 impact on flow specification process, and error handling per 923 [RFC7606]. 925 The traffic actions are processed in ascending order of the sub-type 926 found in the BGP Extended Communities. 928 6.1. Traffic Rate in bytes (sub-type 0x06) 930 The traffic-rate extended community is a non- transitive extended 931 community across the autonomous-system boundary and uses following 932 extended community encoding: 934 The first two octets carry the 2-octet id, which can be assigned from 935 a 2-byte AS number. When a 4-byte AS number is locally present, the 936 2 least significant bytes of such an AS number can be used. This 937 value is purely informational and should not be interpreted by the 938 implementation. 940 The remaining 4 octets carry the maximum rate information in IEEE 941 floating point [IEEE.754.1985] format, units being bytes per second. 942 A traffic-rate of 0 should result on all traffic for the particular 943 flow to be discarded. 945 Interfers with: Traffic Rate in packets. Process traffic rate in 946 bytes (sub-type 0x06) action before traffic rate action (sub-type 947 TBD). 949 6.2. Traffic-action (sub-type 0x07) 951 The traffic-action extended community consists of 6 bytes of which 952 only the 2 least significant bits of the 6th byte (from left to 953 right) are currently defined. 955 40 41 42 43 44 45 46 47 956 +---+---+---+---+---+---+---+---+ 957 | reserved | S | T | 958 +---+---+---+---+---+---+---+---+ 960 where S and T are defined as: 962 o T: Terminal Action (bit 47): When this bit is set, the traffic 963 filtering engine will apply any subsequent filtering rules (as 964 defined by the ordering procedure). If not set, the evaluation of 965 the traffic filter stops when this rule is applied. 967 o S:Sample (bit 46): Enables traffic sampling and logging for this 968 flow specification. 970 Interfers with: No other BGP Flow Specification traffic action in 971 this document. 973 6.3. IP Redirect (sub-type 0x08) 975 The redirect extended community allows the traffic to be redirected 976 to a VRF routing instance that lists the specified route-target in 977 its import policy. If several local instances match this criteria, 978 the choice between them is a local matter (for example, the instance 979 with the lowest Route Distinguisher value can be elected). This 980 extended community uses the same encoding as the Route Target 981 extended community [RFC4360]. 983 It should be noted that the low-order nibble of the Redirect's Type 984 field corresponds to the Route Target Extended Community format field 985 (Type). (See Sections 3.1, 3.2, and 4 of [RFC4360] plus Section 2 of 986 [RFC5668].) The low-order octet (Sub-Type) of the Redirect Extended 987 Community remains 0x08 for all three encodings of the BGP Extended 988 Communities (AS 2-byte, AS 4-byte, and IPv4 address). 990 Interfers with: All other redirect functions. All redirect functions 991 are mutually exclusive. If this redirect function exists, then no 992 other redirect functions can be processed. 994 6.4. Traffic Marking (sub-type 0x09) 996 The traffic marking extended community instructs a system to modify 997 the DSCP bits of a transiting IP packet to the corresponding value. 998 This extended community is encoded as a sequence of 5 zero bytes 999 followed by the DSCP value encoded in the 6 least significant bits of 1000 6th byte. 1002 Interfers with: No other action in this document. 1004 6.5. Rules on Traffic Action interference 1006 The following traffic Actions may interfere with each other: 1008 o redirect actions, 1010 o traffic rate actions, and 1012 o encapsulation actions. 1014 This specification has the following rules regaarding multiple 1015 traffic actions to prevent the interference: 1017 1. All redirect actions are mutually exclusive. Presence of more 1018 than one results in no redirect. 1020 2. If multiple rate actions are present, these are applied in 1021 ascending order of the sub-type. 1023 3. Some actions are unique, and may operate independently. For 1024 example, an MPLS push/pop action is unique. 1026 4. Each additional flow specification Action must specify: 1028 * whether it is a redirect or rate action, 1030 * whether the action is unique or if it interfers with other 1031 actions, 1033 * If the action interfers with other actions, the handling must 1034 be specified if both the action and other interfering actions 1035 exist are associated with a Flow specification NLRI. 1037 7. Dissemination of Traffic Filtering in BGP/MPLS VPN Networks 1039 Provider-based Layer 3 VPN networks, such as the ones using a BGP/ 1040 MPLS IP VPN [RFC4364] control plane, have different traffic filtering 1041 requirements than Internet service providers. This document proposes 1042 an additional BGP NLRI type (AFI=1, SAFI=134) value, which can be 1043 used to propagate traffic filtering information in a BGP/MPLS VPN 1044 environment. 1046 The NLRI format for this address family consists of a fixed-length 1047 Route Distinguisher field (8 bytes) followed by a flow specification, 1048 following the encoding defined above in section x of this document. 1049 The NLRI length field shall include both the 8 bytes of the Route 1050 Distinguisher as well as the subsequent flow specification. 1052 +------------------------------+ 1053 | length (0xnn or 0xfn nn) | 1054 +------------------------------+ 1055 | Route Distinguisher (8 bytes)| 1056 +------------------------------+ 1057 | NLRI value (variable) | 1058 +------------------------------+ 1060 Figure 2: Flow-spec NLRI for MPLS 1062 Propagation of this NLRI is controlled by matching Route Target 1063 extended communities associated with the BGP path advertisement with 1064 the VRF import policy, using the same mechanism as described in "BGP/ 1065 MPLS IP VPNs" [RFC4364]. 1067 Flow specification rules received via this NLRI apply only to traffic 1068 that belongs to the VRF(s) in which it is imported. By default, 1069 traffic received from a remote PE is switched via an MPLS forwarding 1070 decision and is not subject to filtering. 1072 Contrary to the behavior specified for the non-VPN NLRI, flow rules 1073 are accepted by default, when received from remote PE routers. 1075 7.1. Validation Procedures for BGP/MPLS VPNs 1077 The validation procedures are the same as for IPv4. 1079 7.2. Traffic Actions Rules 1081 The traffic action rules are the same as for IPv4. 1083 8. Limitations of Previous Traffic Filtering Efforts 1085 8.1. Limitations in Previous DDOS Traffic Filtering Efforts 1087 The popularity of traffic-based, denial-of-service (DoS) attacks, 1088 which often requires the network operator to be able to use traffic 1089 filters for detection and mitigation, brings with it requirements 1090 that are not fully satisfied by existing tools. 1092 Increasingly, DoS mitigation requires coordination among several 1093 service providers in order to be able to identify traffic source(s) 1094 and because the volumes of traffic may be such that they will 1095 otherwise significantly affect the performance of the network. 1097 Several techniques are currently used to control traffic filtering of 1098 DoS attacks. Among those, one of the most common is to inject 1099 unicast route advertisements corresponding to a destination prefix 1100 being attacked. One variant of this technique marks such route 1101 advertisements with a community that gets translated into a discard 1102 Next-Hop by the receiving router. Other variants attract traffic to 1103 a particular node that serves as a deterministic drop point. 1105 Using unicast routing advertisements to distribute traffic filtering 1106 information has the advantage of using the existing infrastructure 1107 and inter-AS communication channels. This can allow, for instance, a 1108 service provider to accept filtering requests from customers for 1109 address space they own. 1111 There are several drawbacks, however. An issue that is immediately 1112 apparent is the granularity of filtering control: only destination 1113 prefixes may be specified. Another area of concern is the fact that 1114 filtering information is intermingled with routing information. 1116 The mechanism defined in this document is designed to address these 1117 limitations. We use the flow specification NLRI defined above to 1118 convey information about traffic filtering rules for traffic that 1119 should be discarded. 1121 8.2. Limitations in Previous BGP/MPLS Traffic Monitoring 1123 Provider-based Layer 3 VPN networks, such as the ones using a BGP/ 1124 MPLS IP VPN [RFC4364] control plane, have different traffic filtering 1125 requirements than Internet service providers. 1127 In these environments, the VPN customer network often has traffic 1128 filtering capabilities towards their external network connections 1129 (e.g., firewall facing public network connection). Less common is 1130 the presence of traffic filtering capabilities between different VPN 1131 attachment sites. In an any-to-any connectivity model, which is the 1132 default, this means that site-to-site traffic is unfiltered. 1134 In circumstances where a security threat does get propagated inside 1135 the VPN customer network, there may not be readily available 1136 mechanisms to provide mitigation via traffic filter. 1138 The BGP Flow Specification version 1 addresses these limitations. 1140 8.3. Limitations in BGP Flow Specification for SDN/NFV Applications 1142 The SDN/NFV applications which use centralized control of network 1143 traffic via dynamic distribution of traffic filters can utilize the 1144 BGP Flow Specification version 1 described in this draft with a fixed 1145 order to traffic filter matches. However, for control of large 1146 amounts of data a user-defined order to traffic matches and actions 1147 may be required. 1149 9. Traffic Monitoring 1151 Traffic filtering applications require monitoring and traffic 1152 statistics facilities. While this is an implementation-specific 1153 choice, implementations SHOULD provide: 1155 o A mechanism to log the packet header of filtered traffic. 1157 o A mechanism to count the number of matches for a given flow 1158 specification rule. 1160 10. IANA Considerations 1162 This section complies with [RFC7153] 1164 10.1. AFI/SAFI Definitions 1166 For the purpose of this work, IANA has allocated values for two 1167 SAFIs: SAFI 133 for IPv4 dissemination of flow specification rules 1168 and SAFI 134 for VPNv4 dissemination of flow specification rules. 1170 10.2. Flow Component definitions 1172 A flow specification consists of a sequence of flow components, which 1173 are identified by a an 8-bit component type. Types must be assigned 1174 and interpreted uniquely. The current specification defines types 1 1175 though 12, with the value 0 being reserved. 1177 IANA created and maintains a new registry entitled: "Flow Spec 1178 Component Types". The following component types have been 1179 registered: 1181 Type 1 - Destination Prefix 1183 Type 2 - Source Prefix 1185 Type 3 - IP Protocol 1186 Type 4 - Port 1188 Type 5 - Destination port 1190 Type 6 - Source port 1192 Type 7 - ICMP type 1194 Type 8 - ICMP code 1196 Type 9 - TCP flags 1198 Type 10 - Packet length 1200 Type 11 - DSCP 1202 Type 12 - Fragment 1204 In order to manage the limited number space and accommodate several 1205 usages, the following policies defined by RFC 5226 [RFC5226] are 1206 used: 1208 +--------------+-------------------------------+ 1209 | Range | Policy | 1210 +--------------+-------------------------------+ 1211 | 0 | Invalid value | 1212 | [1 .. 12] | Defined by this specification | 1213 | [13 .. 127] | Specification Required | 1214 | [128 .. 255] | First Come First Served | 1215 +--------------+-------------------------------+ 1217 The specification of a particular "flow component type" must clearly 1218 identify what the criteria used to match packets forwarded by the 1219 router is. This criteria should be meaningful across router hops and 1220 not depend on values that change hop-by-hop such as TTL or Layer 2 1221 encapsulation. 1223 The "traffic-action" extended community defined in this document has 1224 46 unused bits, which can be used to convey additional meaning. IANA 1225 created and maintains a new registry entitled: "Traffic Action 1226 Fields". These values should be assigned via IETF Review rules only. 1227 The following traffic-action fields have been allocated: 1229 47 Terminal Action 1231 46 Sample 1233 0-45 Unassigned 1235 10.3. Extended Community Flow Specification Actions 1237 The Extended Community FLow Specification Action types consists of 1238 two parts: BGP Transitive Extended Community types and a set of sub- 1239 types. 1241 IANA has updated the following "BGP Transitive Extended Community 1242 Types" registries to contain the values listed below: 1244 0x80 - Generic Transitive Experimental Use Extended Community Part 1245 1 (Sub-Types are defined in the "Generic Transitive Experimental 1246 Extended Community Part 1 Sub-Types" Registry) 1248 0x81 - Generic Transitive Experimental Use Extended Community Part 1249 2 (Sub-Types are defined in the "Generic Transitive Experimental 1250 Extended Community Part 2 Sub-Types" Registry) 1252 0x82 - Generic Transitive Experimental Use Extended Community Part 1253 3 (Sub-Types are defined in the "Generic Transitive Experimental 1254 Use Extended Community Part 3 Sub-Types" Registry) 1256 RANGE REGISTRATION PROCEDURE 1257 0x00-0xbf First Come First Served 1258 0xc0-0xff IETF Review 1260 SUB-TYPE VALUE NAME REFERENCE 1261 0x00-0x05 unassigned 1262 0x06 traffic-rate [this document] 1263 0x07 traffic-action [this document] 1264 0x08 Flow spec redirect IPv4 [RFC5575] [RFC7674] 1265 [this document] 1266 0x09 traffic-marking [this document] 1267 0x10-0xff Unassigned [this document] 1269 11. Security Considerations 1271 Inter-provider routing is based on a web of trust. Neighboring 1272 autonomous systems are trusted to advertise valid reachability 1273 information. If this trust model is violated, a neighboring 1274 autonomous system may cause a denial-of-service attack by advertising 1275 reachability information for a given prefix for which it does not 1276 provide service. 1278 As long as traffic filtering rules are restricted to match the 1279 corresponding unicast routing paths for the relevant prefixes, the 1280 security characteristics of this proposal are equivalent to the 1281 existing security properties of BGP unicast routing. 1283 Where it is not the case, this would open the door to further denial- 1284 of-service attacks. 1286 Enabling firewall-like capabilities in routers without centralized 1287 management could make certain failures harder to diagnose. For 1288 example, it is possible to allow TCP packets to pass between a pair 1289 of addresses but not ICMP packets. It is also possible to permit 1290 packets smaller than 900 or greater than 1000 bytes to pass between a 1291 pair of addresses, but not packets whose length is in the range 900- 1292 1000. Such behavior may be confusing and these capabilities should 1293 be used with care whether manually configured or coordinated through 1294 the protocol extensions described in this document. 1296 12. Original RFC5575 authors 1298 Barry Greene, MuPedro Marques, Jared Mauch, Danny McPherson, Robert 1299 Rasuzk, and Nischal Sheth were authors on [RFC5575], and therefore 1300 are contributing authors on this document. 1302 Note: Any original authors that want to work on this text will be 1303 added in as authors. 1305 13. Acknowledgements 1307 The authors would like to thank Yakov Rekhter, Dennis Ferguson, Chris 1308 Morrow, Charlie Kaufman, and David Smith for their comments for the 1309 comments on the original [RFC5575]. Chaitanya Kodeboyina helped 1310 design the flow validation procedure; and Steven Lin and Jim Washburn 1311 ironed out all the details necessary to produce a working 1312 implementation in the original [RFC5575]. 1314 Additional acknowledgements for this document will be included here. 1316 14. References 1318 14.1. Normative References 1320 [RFC0793] Postel, J., "Transmission Control Protocol", STD 7, 1321 RFC 793, DOI 10.17487/RFC0793, September 1981, 1322 . 1324 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1325 Requirement Levels", BCP 14, RFC 2119, 1326 DOI 10.17487/RFC2119, March 1997, 1327 . 1329 [RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black, 1330 "Definition of the Differentiated Services Field (DS 1331 Field) in the IPv4 and IPv6 Headers", RFC 2474, 1332 DOI 10.17487/RFC2474, December 1998, 1333 . 1335 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 1336 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 1337 DOI 10.17487/RFC4271, January 2006, 1338 . 1340 [RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended 1341 Communities Attribute", RFC 4360, DOI 10.17487/RFC4360, 1342 February 2006, . 1344 [RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private 1345 Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February 1346 2006, . 1348 [RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, 1349 "Multiprotocol Extensions for BGP-4", RFC 4760, 1350 DOI 10.17487/RFC4760, January 2007, 1351 . 1353 [RFC4761] Kompella, K., Ed. and Y. Rekhter, Ed., "Virtual Private 1354 LAN Service (VPLS) Using BGP for Auto-Discovery and 1355 Signaling", RFC 4761, DOI 10.17487/RFC4761, January 2007, 1356 . 1358 [RFC4762] Lasserre, M., Ed. and V. Kompella, Ed., "Virtual Private 1359 LAN Service (VPLS) Using Label Distribution Protocol (LDP) 1360 Signaling", RFC 4762, DOI 10.17487/RFC4762, January 2007, 1361 . 1363 [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an 1364 IANA Considerations Section in RFCs", BCP 26, RFC 5226, 1365 DOI 10.17487/RFC5226, May 2008, 1366 . 1368 [RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J., 1369 and D. McPherson, "Dissemination of Flow Specification 1370 Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009, 1371 . 1373 [RFC5668] Rekhter, Y., Sangli, S., and D. Tappan, "4-Octet AS 1374 Specific BGP Extended Community", RFC 5668, 1375 DOI 10.17487/RFC5668, October 2009, 1376 . 1378 [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., 1379 and A. Bierman, Ed., "Network Configuration Protocol 1380 (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, 1381 . 1383 [RFC6482] Lepinski, M., Kent, S., and D. Kong, "A Profile for Route 1384 Origin Authorizations (ROAs)", RFC 6482, 1385 DOI 10.17487/RFC6482, February 2012, 1386 . 1388 [RFC7153] Rosen, E. and Y. Rekhter, "IANA Registries for BGP 1389 Extended Communities", RFC 7153, DOI 10.17487/RFC7153, 1390 March 2014, . 1392 [RFC7223] Bjorklund, M., "A YANG Data Model for Interface 1393 Management", RFC 7223, DOI 10.17487/RFC7223, May 2014, 1394 . 1396 [RFC7606] Chen, E., Ed., Scudder, J., Ed., Mohapatra, P., and K. 1397 Patel, "Revised Error Handling for BGP UPDATE Messages", 1398 RFC 7606, DOI 10.17487/RFC7606, August 2015, 1399 . 1401 [RFC7674] Haas, J., Ed., "Clarification of the Flowspec Redirect 1402 Extended Community", RFC 7674, DOI 10.17487/RFC7674, 1403 October 2015, . 1405 14.2. Informative References 1407 [I-D.ietf-idr-bgp-flowspec-label] 1408 liangqiandeng, l., Hares, S., You, J., Raszuk, R., and d. 1409 danma@cisco.com, "Carrying Label Information for BGP 1410 FlowSpec", draft-ietf-idr-bgp-flowspec-label-00 (work in 1411 progress), June 2016. 1413 [I-D.ietf-idr-bgp-flowspec-oid] 1414 Uttaro, J., Filsfils, C., Smith, D., Alcaide, J., and P. 1415 Mohapatra, "Revised Validation Procedure for BGP Flow 1416 Specifications", draft-ietf-idr-bgp-flowspec-oid-03 (work 1417 in progress), March 2016. 1419 [I-D.ietf-idr-flow-spec-v6] 1420 McPherson, D., Raszuk, R., Pithawala, B., 1421 akarch@cisco.com, a., and S. Hares, "Dissemination of Flow 1422 Specification Rules for IPv6", draft-ietf-idr-flow-spec- 1423 v6-07 (work in progress), March 2016. 1425 [I-D.ietf-idr-flowspec-interfaceset] 1426 Litkowski, S., Simpson, A., Patel, K., and J. Haas, 1427 "Applying BGP flowspec rules on a specific interface set", 1428 draft-ietf-idr-flowspec-interfaceset-01 (work in 1429 progress), June 2016. 1431 [I-D.ietf-idr-flowspec-l2vpn] 1432 Weiguo, H., liangqiandeng, l., Litkowski, S., and S. 1433 Zhuang, "Dissemination of Flow Specification Rules for L2 1434 VPN", draft-ietf-idr-flowspec-l2vpn-04 (work in progress), 1435 May 2016. 1437 [I-D.ietf-idr-flowspec-mpls-match] 1438 Yong, L., Hares, S., liangqiandeng, l., and J. You, "BGP 1439 Flow Specification Filter for MPLS Label", draft-ietf-idr- 1440 flowspec-mpls-match-00 (work in progress), May 2016. 1442 [I-D.ietf-idr-flowspec-nvo3] 1443 Weiguo, H., Zhuang, S., Li, Z., and R. Gu, "Dissemination 1444 of Flow Specification Rules for NVO3", draft-ietf-idr- 1445 flowspec-nvo3-00 (work in progress), May 2016. 1447 [I-D.ietf-idr-flowspec-packet-rate] 1448 Eddy, W., Dailey, J., and G. Clark, "BGP Flow 1449 Specification Packet-Rate Action", draft-ietf-idr- 1450 flowspec-packet-rate-00 (work in progress), June 2016. 1452 [I-D.ietf-idr-wide-bgp-communities] 1453 Raszuk, R., Haas, J., Lange, A., Amante, S., Decraene, B., 1454 Jakma, P., and R. Steenbergen, "Wide BGP Communities 1455 Attribute", draft-ietf-idr-wide-bgp-communities-02 (work 1456 in progress), May 2016. 1458 [RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)", 1459 RFC 4303, DOI 10.17487/RFC4303, December 2005, 1460 . 1462 [RFC6074] Rosen, E., Davie, B., Radoaca, V., and W. Luo, 1463 "Provisioning, Auto-Discovery, and Signaling in Layer 2 1464 Virtual Private Networks (L2VPNs)", RFC 6074, 1465 DOI 10.17487/RFC6074, January 2011, 1466 . 1468 [RFC6483] Huston, G. and G. Michaelson, "Validation of Route 1469 Origination Using the Resource Certificate Public Key 1470 Infrastructure (PKI) and Route Origin Authorizations 1471 (ROAs)", RFC 6483, DOI 10.17487/RFC6483, February 2012, 1472 . 1474 Author's Address 1476 Susan Hares 1477 Huawei 1478 7453 Hickory Hill 1479 Saline, MI 48176 1480 USA 1482 Email: shares@ndzh.com