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Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 IDR Working Group R. Raszuk 3 Internet-Draft Bloomberg LP 4 Intended status: Standards Track S. Hares 5 Expires: January 9, 2017 Huawei 6 July 8, 2016 8 Dissemination of Flow Specification Rules 9 draft-hr-idr-rfc5575bis-00.txt 11 Abstract 13 This document updates RFC5575 which defines a Border Gateway Protocol 14 Network Layer Reachability Information (BGP NLRI) encoding format 15 that can be used to distribute traffic flow specifications. This 16 allows the routing system to propagate information regarding more 17 specific components of the traffic aggregate defined by an IP 18 destination prefix. This draft specifices IPv4 traffic flow 19 specificaitnos. Other drafst specify , IPv6), MPLS addresses, L2VPN 20 addresses, and NV03 encapsulation of IP addresses. The information 21 is carried via the BGP, thereby reusing protocol algorithms, 22 operational experience, and administrative processes such as inter- 23 provider peering agreements. 25 There are applications of that encoding format: 1) automation of 26 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. This defines the first two applications. 35 This document provides the definition of a BGP NLRI which carries 36 traffic flow specification filters, and Extended Community values 37 which encode the actions a routing system can take if a packet 38 matches the traffic flow filters. The specification requires that 39 the BGP Flow Specification traffic filters follows a string ordering, 40 and that the BGP Flow Specification Extended Communities actions are 41 processed in a defined order. 43 Status of This Memo 45 This Internet-Draft is submitted in full conformance with the 46 provisions of BCP 78 and BCP 79. 48 Internet-Drafts are working documents of the Internet Engineering 49 Task Force (IETF). Note that other groups may also distribute 50 working documents as Internet-Drafts. The list of current Internet- 51 Drafts is at http://datatracker.ietf.org/drafts/current/. 53 Internet-Drafts are draft documents valid for a maximum of six months 54 and may be updated, replaced, or obsoleted by other documents at any 55 time. It is inappropriate to use Internet-Drafts as reference 56 material or to cite them other than as "work in progress." 58 This Internet-Draft will expire on January 9, 2017. 60 Copyright Notice 62 Copyright (c) 2016 IETF Trust and the persons identified as the 63 document authors. All rights reserved. 65 This document is subject to BCP 78 and the IETF Trust's Legal 66 Provisions Relating to IETF Documents 67 (http://trustee.ietf.org/license-info) in effect on the date of 68 publication of this document. Please review these documents 69 carefully, as they describe your rights and restrictions with respect 70 to this document. Code Components extracted from this document must 71 include Simplified BSD License text as described in Section 4.e of 72 the Trust Legal Provisions and are provided without warranty as 73 described in the Simplified BSD License. 75 Table of Contents 77 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 78 2. Definitions of Terms Used in This Memo . . . . . . . . . . . 5 79 3. Flow Specifications . . . . . . . . . . . . . . . . . . . . . 6 80 4. Dissemination of IPv4 FLow Specification Information . . . . 6 81 4.1. Length Encoding . . . . . . . . . . . . . . . . . . . . . 7 82 4.2. NLRI Value Encoding . . . . . . . . . . . . . . . . . . . 7 83 4.2.1. Type 1 - Destination Prefix . . . . . . . . . . . . . 8 84 4.2.2. Type 2 - Source Prefix . . . . . . . . . . . . . . . 8 85 4.2.3. Type 3 - Source Prefix . . . . . . . . . . . . . . . 8 86 4.2.4. Type 4 - Port . . . . . . . . . . . . . . . . . . . . 9 87 4.2.5. Type 5 - Destination Port . . . . . . . . . . . . . . 9 88 4.2.6. Type 6 - Destination Port . . . . . . . . . . . . . . 9 89 4.2.7. Type 7 - ICMP type . . . . . . . . . . . . . . . . . 10 90 4.2.8. Type 8 - ICMP code . . . . . . . . . . . . . . . . . 10 91 4.2.9. Type 9 - ICMP code . . . . . . . . . . . . . . . . . 10 92 4.2.10. Type 10 - Packet length . . . . . . . . . . . . . . . 11 93 4.2.11. Type 11 - DSCP (Diffserv Code Point) . . . . . . . . 11 94 4.2.12. Type 12 - Fragment . . . . . . . . . . . . . . . . . 11 95 4.2.13. Type 13 - Bit-Mask Filter . . . . . . . . . . . . . . 11 97 4.3. Examples of Encodings . . . . . . . . . . . . . . . . . . 12 98 5. Traffic Filtering . . . . . . . . . . . . . . . . . . . . . . 13 99 5.1. Ordering of Traffic Filtering Rules . . . . . . . . . . . 14 100 6. Validation Procedure . . . . . . . . . . . . . . . . . . . . 15 101 7. Traffic Filtering Actions . . . . . . . . . . . . . . . . . . 16 102 7.1. Traffic Rate in bytes (sub-type 0x06) . . . . . . . . . . 18 103 7.2. Traffic-action (sub-type 0x07) . . . . . . . . . . . . . 18 104 7.3. IP Redirect (sub-type 0x08) . . . . . . . . . . . . . . . 19 105 7.4. Traffic Marking (sub-type 0x09) . . . . . . . . . . . . . 19 106 7.5. Rules on Traffic Action interference . . . . . . . . . . 19 107 8. Dissemination of Traffic Filtering in BGP/MPLS VPN Networks . 20 108 8.1. Validation Procedures for BGP/MPLS VPNs . . . . . . . . . 21 109 8.2. Traffic Actions Rules . . . . . . . . . . . . . . . . . . 21 110 9. Limitations of Previous Traffic Filtering Efforts . . . . . . 21 111 9.1. Limitations in Previous DDOS Traffic Filtering Efforts . 21 112 9.2. Limitations in Previous BGP/MPLS Traffic Monitoring . . . 22 113 10. Traffic Monitoring . . . . . . . . . . . . . . . . . . . . . 22 114 11. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 22 115 11.1. AFI/SAFI Definitions . . . . . . . . . . . . . . . . . . 23 116 11.2. Flow Component definitions . . . . . . . . . . . . . . . 23 117 11.3. Extended Community Flow Specification Actions . . . . . 24 118 12. Security Considerations . . . . . . . . . . . . . . . . . . . 25 119 13. Original authors . . . . . . . . . . . . . . . . . . . . . . 25 120 14. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 26 121 15. References . . . . . . . . . . . . . . . . . . . . . . . . . 26 122 15.1. Normative References . . . . . . . . . . . . . . . . . . 26 123 15.2. Informative References . . . . . . . . . . . . . . . . . 28 124 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 29 126 1. Introduction 128 Modern IP routers contain both the capability to forward traffic 129 according to IP prefixes as well as to classify, shape, rate limit, 130 filter, or redirect packets based on administratively defined 131 policies. 133 These traffic policy mechanisms allow the router to define match 134 rules that operate on multiple fields of the packet header. Actions 135 such as the ones described above can be associated with each rule. 137 The n-tuple consisting of the matching criteria defines an aggregate 138 traffic flow specification. The matching criteria can include 139 elements such as source and destination address prefixes, IP 140 protocol, and transport protocol port numbers. 142 This document defines a general procedure to encode flow 143 specification rules for aggregated traffic flows so that they can be 144 distributed as a BGP [RFC5575] NLRI. Additionally, we define the 145 required mechanisms to utilize this definition to the problem of 146 immediate concern to the authors: intra- and inter-provider 147 distribution of traffic filtering rules to filter (distributed) 148 denial-of-service (DoS) attacks. 150 By expanding routing information with flow specifications, the 151 routing system can take advantage of the ACL (Access Control List) or 152 firewall capabilities in the router's forwarding path. Flow 153 specifications can be seen as more specific routing entries to a 154 unicast prefix and are expected to depend upon the existing unicast 155 data information. 157 A flow specification received from an external autonomous system will 158 need to be validated against unicast routing before being accepted. 159 If the aggregate traffic flow defined by the unicast destination 160 prefix is forwarded to a given BGP peer, then the local system can 161 safely install more specific flow rules that may result in different 162 forwarding behavior, as requested by this system. 164 The key technology components required to address the class of 165 problems targeted by this document are: 167 1. Efficient point-to-multipoint distribution of control plane 168 information. 170 2. Inter-domain capabilities and routing policy support. 172 3. Tight integration with unicast routing, for verification 173 purposes. 175 Items 1 and 2 have already been addressed using BGP for other types 176 of control plane information. Close integration with BGP also makes 177 it feasible to specify a mechanism to automatically verify flow 178 information against unicast routing. These factors are behind the 179 choice of BGP as the carrier of flow specification information. 181 As with previous extensions to BGP, this specification makes it 182 possible to add additional information to Internet routers. These 183 are limited in terms of the maximum number of data elements they can 184 hold as well as the number of events they are able to process in a 185 given unit of time. The authors believe that, as with previous 186 extensions, service providers will be careful to keep information 187 levels below the maximum capacity of their devices. 189 In many deployments of BGP Flow Specification, the flow specification 190 information has replace existing host length route advertisements. 192 Experience with previous BGP extensions has also shown that the 193 maximum capacity of BGP speakers has been gradually increased 194 according to expected loads. Taking into account Internet unicast 195 routing as well as additional applications as they gain popularity. 197 From an operational perspective, the utilization of BGP as the 198 carrier for this information allows a network service provider to 199 reuse both internal route distribution infrastructure (e.g., route 200 reflector or confederation design) and existing external 201 relationships (e.g., inter-domain BGP sessions to a customer 202 network). 204 While it is certainly possible to address this problem using other 205 mechanisms, this solution has been utilized in deployments because of 206 the substantial advantage of being an incremental addition to already 207 deployed mechanisms. 209 In current deployments, the information distributed by the flow-spec 210 extension is originated both manually as well as automatically. The 211 latter by systems that are able to detect malicious flows. When 212 automated systems are used, care should be taken to ensure their 213 correctness as well as to limit the number and advertisement rate of 214 flow routes. 216 This specification defines required protocol extensions to address 217 most common applications of IPv4 unicast and VPNv4 unicast filtering. 218 The same mechanism can be reused and new match criteria added to 219 address similar filtering needs for other BGP address families such 220 as IPv6 families [I-D.ietf-idr-flow-spec-v6], 222 2. Definitions of Terms Used in This Memo 224 NLRI - Network Layer Reachability Information. 226 RIB - Routing Information Base. 228 Loc-RIB - Local RIB. 230 AS - Autonomous System number. 232 VRF - Virtual Routing and Forwarding instance. 234 PE - Provider Edge router 236 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 237 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 238 document are to be interpreted as described in [RFC2119] 240 3. Flow Specifications 242 A flow specification is an n-tuple consisting of several matching 243 criteria that can be applied to IP traffic. A given IP packet is 244 said to match the defined flow if it matches all the specified 245 criteria. 247 A given flow may be associated with a set of attributes, depending on 248 the particular application; such attributes may or may not include 249 reachability information (i.e., NEXT_HOP). Well-known or AS-specific 250 community attributes can be used to encode a set of predetermined 251 actions. 253 A particular application is identified by a specific (Address Family 254 Identifier, Subsequent Address Family Identifier (AFI, SAFI)) pair 255 [RFC4760] and corresponds to a distinct set of RIBs. Those RIBs 256 should be treated independently from each other in order to assure 257 non-interference between distinct applications. 259 BGP itself treats the NLRI as an opaque key to an entry in its 260 databases. Entries that are placed in the Loc-RIB are then 261 associated with a given set of semantics, which is application 262 dependent. This is consistent with existing BGP applications. For 263 instance, IP unicast routing (AFI=1, SAFI=1) and IP multicast 264 reverse-path information (AFI=1, SAFI=2) are handled by BGP without 265 any particular semantics being associated with them until installed 266 in the Loc-RIB. 268 Standard BGP policy mechanisms, such as UPDATE filtering by NLRI 269 prefix and community matching, SHOULD apply to the Flow specification 270 defined NLRI-type. Network operators can also control propagation of 271 such routing updates by enabling or disabling the exchange of a 272 particular (AFI, SAFI) pair on a given BGP peering session. 274 4. Dissemination of IPv4 FLow Specification Information 276 We define a "Flow Specification" NLRI type that may include several 277 components such as destination prefix, source prefix, protocol, 278 ports, and others (see Tables 1-4 below). This NLRI is treated as an 279 opaque bit string prefix by BGP. Each bit string identifies a key to 280 a database entry with which a set of attributes can be associated. 282 This NLRI information is encoded using MP_REACH_NLRI and 283 MP_UNREACH_NLRI attributes as defined in [RFC4760]. Whenever the 284 corresponding application does not require Next-Hop information, this 285 shall be encoded as a 0-octet length Next Hop in the MP_REACH_NLRI 286 attribute and ignored on receipt. 288 The NLRI field of the MP_REACH_NLRI and MP_UNREACH_NLRI is encoded as 289 a 1- or 2-octet NLRI length field followed by a variable-length NLRI 290 value. The NLRI length is expressed in octets. 292 +------------------------------+ 293 | length (0xnn or 0xfn nn) | 294 +------------------------------+ 295 | NLRI value (variable) | 296 +------------------------------+ 298 Figure 1: Flow-spec NLRI for IPv4 300 Implementations wishing to exchange flow specification rules MUST use 301 BGP's Capability Advertisement facility to exchange the Multiprotocol 302 Extension Capability Code (Code 1) as defined in [RFC4760]. The 303 (AFI, SAFI) pair carried in the Multiprotocol Extension Capability 304 MUST be the same as the one used to identify a particular application 305 that uses this NLRI-type. 307 4.1. Length Encoding 309 o If the NLRI length value is smaller than 240 (0xf0 hex), the 310 length field can be encoded as a single octet. 312 o Otherwise, it is encoded as an extended-length 2-octet value in 313 which the most significant nibble of the first byte is all ones. 315 In figure 1 above, values less-than 240 are encoded using two hex 316 digits (0xnn). Values above 240 are encoded using 3 hex digits 317 (0xfnnn). The highest value that can be represented with this 318 encoding is 4095. The value 241 is encoded as 0xf0f1. 320 4.2. NLRI Value Encoding 322 The Flow specification NLRI-type consists of several optional 323 subcomponents. A specific packet is considered to match the flow 324 specification when it matches the intersection (AND) of all the 325 components present in the specification. The encoding of each of the 326 NLRI components begins with a type field as listed in Table 1-4. 327 Sections 4.2.1 to 4.2.12 contain the specific encodings for the IPv4 328 IP layer and transport layer headings. IPv6 filters are described 329 in: [I-D.ietf-idr-flow-spec-v6]. 331 Flow specification components must follow strict type ordering by 332 increasing numerical order. A given component type may or may not be 333 present in the specification, but if present, it MUST precede any 334 component of higher numeric type value. 336 If a given component type within a prefix in unknown, the prefix in 337 question cannot be used for traffic filtering purposes by the 338 receiver. Since a flow specification has the semantics of a logical 339 AND of all components, if a component is FALSE, by definition it 340 cannot be applied. However, for the purposes of BGP route 341 propagation, this prefix should still be transmitted since BGP route 342 distribution is independent on NLRI semantics. 344 The 351 Defines: the destination prefix to match. Prefixes are encoded as 352 in BGP UPDATE messages, a length in bits is followed by enough 353 octets to contain the prefix information. 355 4.2.2. Type 2 - Source Prefix 357 Encoding: 359 Defines the source prefix to match. 361 4.2.3. Type 3 - Source Prefix 363 Encoding: 365 Contains a set of {operator, value} pairs that are used to match 366 the IP protocol value byte in IP packets. 368 The operator byte is encoded as: 370 0 1 2 3 4 5 6 7 371 +---+---+---+---+---+---+---+---+ 372 | e | a | len | 0 |lt |gt |eq | 373 +---+---+---+---+---+---+---+---+ 375 Numerical operator 377 e - end-of-list bit. Set in the last {op, value} pair in the 378 list. 380 a - AND bit. If unset, the previous term is logically ORed with 381 the current one. If set, the operation is a logical AND. It 382 should be unset in the first operator byte of a sequence. The AND 383 operator has higher priority than OR for the purposes of 384 evaluating logical expressions. 386 len - length of the value field for this operand is given as (1 << 387 len). 389 lt - less than comparison between data and value. 391 gt - greater than comparison between data and value. 393 eq -equality between data and value 395 The bits lt, gt, and eq can be combined to produce "less or equal", 396 "greater or equal", and inequality values 398 4.2.4. Type 4 - Port 400 Encoding: 402 Defines a list of {operation, value} pairs that matches source OR 403 destination TCP/UDP ports. This list is encoded using the numeric 404 operand format defined above. Values are encoded as 1- or 2-byte 405 quantities. 407 Port, source port, and destination port components evaluate to 408 FALSE if the IP protocol field of the packet has a value other 409 than TCP or UDP, if the packet is fragmented and this is not the 410 first fragment, or if the system in unable to locate the transport 411 header. Different implementations may or may not be able to 412 decode the transport header in the presence of IP options or 413 Encapsulating Security Payload (ESP) NULL [RFC4303] encryption. 415 4.2.5. Type 5 - Destination Port 417 Encoding: 419 Defines a list of {operation, value} pairs used to match the 420 destination port of a TCP or UDP packet. Values are encoded as 1- 421 or 2-byte quantities 423 4.2.6. Type 6 - Destination Port 425 Encoding: 427 Defines a list of {operation, value} pairs used to match the 428 source port of a TCP or UDP packet. Values are encoded as 1- or 429 2-byte quantities 431 4.2.7. Type 7 - ICMP type 433 Encoding: 435 Defines a list of {operation, value} pairs used to match the type 436 field of an ICMP packet. Values are encoded using a single byte. 438 The ICMP type and code specifiers evaluate to FALSE whenever the 439 protocol value is not ICMP. 441 4.2.8. Type 8 - ICMP code 443 Encoding: 445 Defines a list of {operation, value} pairs used to match the code 446 field of an ICMP packet. Values are encoded using a single byte. 448 4.2.9. Type 9 - ICMP code 450 Encoding: 452 Bitmask values can be encoded as a 1- or 2-byte bitmask. When a 453 single byte is specified, it matches byte 13 of the TCP header 454 [RFC0793], which contains bits 8 though 15 of the 4th 32-bit word. 455 When a 2-byte encoding is used, it matches bytes 12 and 13 of the 456 TCP header with the data offset field having a "don't care" value. 458 As with port specifiers, this component evaluates to FALSE for 459 packets that are not TCP packets. 461 This type uses the bitmask operand format, which differs from the 462 numeric operator format in the lower nibble. 464 0 1 2 3 4 5 6 7 465 +---+---+---+---+---+---+---+---+ 466 | e | a | len | 0 | 0 |not| m | 467 +---+---+---+---+---+---+---+---+ 469 Bitmask format 471 e, a, len - Most significant nibble: (end-of-list bit, AND bit, and 472 length field), as defined for in the numeric operator format. 474 not - NOT bit. If set, logical negation of operation. 476 m - Match bit. If set, this is a bitwise match operation defined 477 as "(data AND value) == value"; if unset, (data AND value) 478 evaluates to TRUE if any of the bits in the value mask are set in 479 the data 481 4.2.10. Type 10 - Packet length 483 Encoding: 485 Defines match on the total IP packet length (excluding Layer 2 but 486 including IP header). Values are encoded using 1- or 2-byte 487 quantities. 489 4.2.11. Type 11 - DSCP (Diffserv Code Point) 491 Encoding: 493 Defines a list of {operation, value} pairs used to match the 6-bit 494 DSCP field [RFC2474]. Values are encoded using a single byte, 495 where the two most significant bits are zero and the six least 496 significant bits contain the DSCP value. 498 4.2.12. Type 12 - Fragment 500 Encoding: 502 Uses bitmask operand format defined above in section 5.2.9. 504 0 1 2 3 4 5 6 7 505 +---+---+---+---+---+---+---+---+ 506 | Reserved |LF |FF |IsF|DF | 507 +---+---+---+---+---+---+---+---+ 509 Bitmask values: 511 Bit 7 - Don't fragment (DF) 513 Bit 6 - Is a fragment (IsF) 515 Bit 5 - First fragment (FF) 517 Bit 4 - Last fragment (LF) 519 4.2.13. Type 13 - Bit-Mask Filter 521 Encoding: 523 where "value" is one or more tuples: 525 [length - in bits of each tuple (2 octets), 527 packet offset location in bits (2 octets), 529 bit field exact pattern match (1-1024 bits)] 531 4.3. Examples of Encodings 533 An example of a flow specification encoding for: "all packets to 534 10.0.1/24 and TCP port 25". 536 +------------------+----------+----------+ 537 | destination | proto | port | 538 +------------------+----------+----------+ 539 | 0x01 18 0a 00 01 | 03 81 06 | 04 81 19 | 540 +------------------+----------+----------+ 542 Decode for protocol: 544 +-------+----------+------------------------------+ 545 | Value | | | 546 +-------+----------+------------------------------+ 547 | 0x03 | type | | 548 | 0x81 | operator | end-of-list, value size=1, = | 549 | 0x06 | value | | 550 +-------+----------+------------------------------+ 552 An example of a flow specification encoding for: "all packets to 553 10.0.1/24 from 192/8 and port {range [137, 139] or 8080}". 555 +------------------+----------+-------------------------+ 556 | destination | source | port | 557 +------------------+----------+-------------------------+ 558 | 0x01 18 0a 01 01 | 02 08 c0 | 04 03 89 45 8b 91 1f 90 | 559 +------------------+----------+-------------------------+ 561 Decode for port: 563 +--------+----------+------------------------------+ 564 | Value | | | 565 +--------+----------+------------------------------+ 566 | 0x04 | type | | 567 | 0x03 | operator | size=1, >= | 568 | 0x89 | value | 137 | 569 | 0x45 | operator | "AND", value size=1, <= | 570 | 0x8b | value | 139 | 571 | 0x91 | operator | end-of-list, value-size=2, = | 572 | 0x1f90 | value | 8080 | 573 +--------+----------+------------------------------+ 575 This constitutes an NLRI with an NLRI length of 16 octets. 577 5. Traffic Filtering 579 Traffic filtering policies have been traditionally considered to be 580 relatively static. Limitations of the static mechanisms caused this 581 mechanism to be designed for the three new applications of traffic 582 filtering (prevention of traffic-based, denial-of-service (DOS) 583 attacks, traffic filtering in the context of BGP/MPLS VPN service, 584 and centralized traffic control for SDN/NFV networks) requires 585 coordination among service providers and/or coordination among the AS 586 within a service provider. Section 8 has details on the limitation 587 of previous mechanisms and why BGP Flow Specification version 1 588 provides a solution for to prevent DOS and aid BGP/MPLS VPN filtering 589 rules. 591 This flow specification NLRI defined above to convey information 592 about traffic filtering rules for traffic that should be discarded or 593 handled in manner specified by a set of pre-defined actions (which 594 are defined in BGP Extended Communities). This mechanism is 595 primarily designed to allow an upstream autonomous system to perform 596 inbound filtering in their ingress routers of traffic that a given 597 downstream AS wishes to drop. 599 In order to achieve this goal, this draft specifies two application 600 specific NLRI identifiers that provide traffic filters, and a set of 601 actions encoding in BGP Extended Communities. The two application 602 specific NLRI identifiers are: 604 o IPv4 flow specification identifier (AFI=1, SAFI=133) along with 605 specific semantic rules for IPv4 routes, and 607 o BGP NLRI type (AFI=1, SAFI=134) value, which can be used to 608 propagate traffic filtering information in a BGP/MPLS VPN 609 environment. 611 Distribution of the IPv4 Flow specification is described in section 612 6, and distibution of BGP/MPLS traffic flow specification is 613 described in section 8. The traffic filtering actions are described 614 in section 7. 616 5.1. Ordering of Traffic Filtering Rules 618 With traffic filtering rules, more than one rule may match a 619 particular traffic flow. Thus, it is necessary to define the order 620 at which rules get matched and applied to a particular traffic flow. 621 This ordering function must be such that it must not depend on the 622 arrival order of the flow specification's rules and must be constant 623 in the network. 625 The relative order of two flow specification rules is determined by 626 comparing their respective components. The algorithm starts by 627 comparing the left-most components of the rules. If the types 628 differ, the rule with lowest numeric type value has higher precedence 629 (and thus will match before) than the rule that doesn't contain that 630 component type. If the component types are the same, then a type- 631 specific comparison is performed. 633 For IP prefix values (IP destination and source prefix) precedence is 634 given to the lowest IP value of the common prefix length; if the 635 common prefix is equal, then the most specific prefix has precedence. 637 For all other component types, unless otherwise specified, the 638 comparison is performed by comparing the component data as a binary 639 string using the memcmp() function as defined by the ISO C standard. 640 For strings of different lengths, the common prefix is compared. If 641 equal, the longest string is considered to have higher precedence 642 than the shorter one. 644 Pseudocode: 646 flow_rule_cmp (a, b) 647 { 648 comp1 = next_component(a); 649 comp2 = next_component(b); 650 while (comp1 || comp2) { 651 // component_type returns infinity on end-of-list 652 if (component_type(comp1) < component_type(comp2)) { 653 return A_HAS_PRECEDENCE; 654 } 655 if (component_type(comp1) > component_type(comp2)) { 656 return B_HAS_PRECEDENCE; 657 } 659 if (component_type(comp1) == IP_DESTINATION || IP_SOURCE) { 660 common = MIN(prefix_length(comp1), prefix_length(comp2)); 661 cmp = prefix_compare(comp1, comp2, common); 662 // not equal, lowest value has precedence 663 // equal, longest match has precedence 664 } else { 665 common = 666 MIN(component_length(comp1), component_length(comp2)); 667 cmp = memcmp(data(comp1), data(comp2), common); 668 // not equal, lowest value has precedence 669 // equal, longest string has precedence 670 } 671 } 673 return EQUAL; 674 } 676 6. Validation Procedure 678 Flow specifications received from a BGP peer and that are accepted in 679 the respective Adj-RIB-In are used as input to the route selection 680 process. Although the forwarding attributes of two routes for the 681 same flow specification prefix may be the same, BGP is still required 682 to perform its path selection algorithm in order to select the 683 correct set of attributes to advertise. 685 The first step of the BGP Route Selection procedure (Section 9.1.2 of 686 [RFC4271] is to exclude from the selection procedure routes that are 687 considered non-feasible. In the context of IP routing information, 688 this step is used to validate that the NEXT_HOP attribute of a given 689 route is resolvable. 691 The concept can be extended, in the case of flow specification NLRI, 692 to allow other validation procedures. 694 A flow specification NLRI must be validated such that it is 695 considered feasible if and only if: 697 a) The originator of the flow specification matches the originator 698 of the best-match unicast route for the destination prefix 699 embedded in the flow specification. 701 b) There are no more specific unicast routes, when compared with 702 the flow destination prefix, that have been received from a 703 different neighboring AS than the best-match unicast route, which 704 has been determined in step a). 706 By originator of a BGP route, we mean either the BGP originator path 707 attribute, as used by route reflection, or the transport address of 708 the BGP peer, if this path attribute is not present. 710 The underlying concept is that the neighboring AS that advertises the 711 best unicast route for a destination is allowed to advertise flow- 712 spec information that conveys a more or equally specific destination 713 prefix. Thus, as long as there are no more specific unicast routes, 714 received from a different neighboring AS, which would be affected by 715 that filtering rule. 717 The neighboring AS is the immediate destination of the traffic 718 described by the flow specification. If it requests these flows to 719 be dropped, that request can be honored without concern that it 720 represents a denial of service in itself. Supposedly, the traffic is 721 being dropped by the downstream autonomous system, and there is no 722 added value in carrying the traffic to it. 724 BGP implementations MUST also enforce that the AS_PATH attribute of a 725 route received via the External Border Gateway Protocol (eBGP) 726 contains the neighboring AS in the left-most position of the AS_PATH 727 attribute. While this rule is optional in the BGP specification, it 728 becomes necessary to enforce it for security reasons. 730 7. Traffic Filtering Actions 732 This specification defines a minimum set of filtering actions that it 733 standardizes as BGP extended community values [RFC4360]. This is not 734 meant to be an inclusive list of all the possible actions, but only a 735 subset that can be interpreted consistently across the network. 736 Additional actions can be defined as either requiring standards or as 737 vendor specific. 739 Implementations SHOULD provide mechanisms that map an arbitrary BGP 740 community value (normal or extended) to filtering actions that 741 require different mappings in different systems in the network. For 742 instance, providing packets with a worse-than-best-effort, per-hop 743 behavior is a functionality that is likely to be implemented 744 differently in different systems and for which no standard behavior 745 is currently known. Rather than attempting to define it here, this 746 can be accomplished by mapping a user-defined community value to 747 platform-/network-specific behavior via user configuration. 749 The default action for a traffic filtering flow specification is to 750 accept IP traffic that matches that particular rule. 752 This document defines the following extended communities values shown 753 in table X in the form 0x8xnn where nn indicates the sub-type. 755 Table 5 - Traffic Action Extended Communities 756 Defined in this document 758 +--------+-----------------------+-------------------------------------+ 759 | type | extended community | encoding | 760 +--------+-----------------------+-------------------------------------+ 761 | 0x8006 | traffic-rate in bytes | 2-byte ASN, 4-byte float | 762 | 0x8007 | traffic-action | bitmask | 763 | 0x8008 | redirect AS-2byte | 2-octet AS, 4-octet Value | 764 | 0x8108 | redirect IPv4 | 4-octet IPv4 Address, 2-octet Value | 765 | 0x8208 | redirect AS-4byte | 4-octet AS, 2-octet Value | 766 | 0x8009 | traffic-marking | DSCP value | 767 +--------+--------------------+----------------------------------------+ 769 Encodings for these extended communities are described below. 771 Some traffic action communities may interfere with each other. 772 Section x.x of this specification provides rules for handling 773 interference between specific types of traffic actions, and error 774 handling based on [RFC7606] in section. Each definition of a traffic 775 action MUST specify any interface with any other traffic actions, any 776 impact on flow specification process, and error handling per 777 [RFC7606]. 779 The traffic actions are processed in ascending order of the sub-type 780 found in the BGP Extended Communities. 782 7.1. Traffic Rate in bytes (sub-type 0x06) 784 The traffic-rate extended community is a non- transitive extended 785 community across the autonomous-system boundary and uses following 786 extended community encoding: 788 The first two octets carry the 2-octet id, which can be assigned from 789 a 2-byte AS number. When a 4-byte AS number is locally present, the 790 2 least significant bytes of such an AS number can be used. This 791 value is purely informational and should not be interpreted by the 792 implementation. 794 The remaining 4 octets carry the maximum rate information in IEEE 795 floating point [IEEE.754.1985] format, units being bytes per second. 796 A traffic-rate of 0 should result on all traffic for the particular 797 flow to be discarded. 799 Interfers with: Traffic Rate in packets. Process traffic rate in 800 bytes (sub-type 0x06) action before traffic rate action (sub-type 801 TBD). 803 7.2. Traffic-action (sub-type 0x07) 805 The traffic-action extended community consists of 6 bytes of which 806 only the 2 least significant bits of the 6th byte (from left to 807 right) are currently defined. 809 40 41 42 43 44 45 46 47 810 +---+---+---+---+---+---+---+---+ 811 | reserved | S | T | 812 +---+---+---+---+---+---+---+---+ 814 where S and T are defined as: 816 o T: Terminal Action (bit 47): When this bit is set, the traffic 817 filtering engine will apply any subsequent filtering rules (as 818 defined by the ordering procedure). If not set, the evaluation of 819 the traffic filter stops when this rule is applied. 821 o S:Sample (bit 46): Enables traffic sampling and logging for this 822 flow specification. 824 Interfers with: No other BGP Flow Specification traffic action in 825 this document. 827 7.3. IP Redirect (sub-type 0x08) 829 The redirect extended community allows the traffic to be redirected 830 to a VRF routing instance that lists the specified route-target in 831 its import policy. If several local instances match this criteria, 832 the choice between them is a local matter (for example, the instance 833 with the lowest Route Distinguisher value can be elected). This 834 extended community uses the same encoding as the Route Target 835 extended community [RFC4360]. 837 It should be noted that the low-order nibble of the Redirect's Type 838 field corresponds to the Route Target Extended Community format field 839 (Type). (See Sections 3.1, 3.2, and 4 of [RFC4360] plus Section 2 of 840 [RFC5668].) The low-order octet (Sub-Type) of the Redirect Extended 841 Community remains 0x08 for all three encodings of the BGP Extended 842 Communities (AS 2-byte, AS 4-byte, and IPv4 address). 844 Interfers with: All other redirect functions. All redirect functions 845 are mutually exclusive. If this redirect function exists, then no 846 other redirect functions can be processed. 848 7.4. Traffic Marking (sub-type 0x09) 850 The traffic marking extended community instructs a system to modify 851 the DSCP bits of a transiting IP packet to the corresponding value. 852 This extended community is encoded as a sequence of 5 zero bytes 853 followed by the DSCP value encoded in the 6 least significant bits of 854 6th byte. 856 Interfers with: No other action in this document. 858 7.5. Rules on Traffic Action interference 860 The following traffic Actions may interfere with each other: 862 o redirect actions, 864 o traffic rate actions, and 866 o encapsulation actions. 868 This specification has the following rules regaarding multiple 869 traffic actions to prevent the interference: 871 1. All redirect actions are mutually exclusive. Presence of more 872 than one results in no redirect. 874 2. If multiple rate actions are present, these are applied in 875 ascending order of the sub-type. 877 3. Some actions are unique, and may operate independently. 879 4. Each additional flow specification action must specify: 881 * whether it is a redirect or rate action, 883 * whether the action is unique or if it interfers with other 884 actions, 886 * If the action interfers with other actions, the handling must 887 be specified if both the action and other interfering actions 888 exist are associated with a Flow specification NLRI. 890 * If the interference between two actions causes an BGP error 891 conditions, the method of handling the error conditions based 892 on [RFC7606]. 894 8. Dissemination of Traffic Filtering in BGP/MPLS VPN Networks 896 Provider-based Layer 3 VPN networks, such as the ones using a BGP/ 897 MPLS IP VPN [RFC4364] control plane, have different traffic filtering 898 requirements than Internet service providers. This document proposes 899 an additional BGP NLRI type (AFI=1, SAFI=134) value, which can be 900 used to propagate traffic filtering information in a BGP/MPLS VPN 901 environment. 903 The NLRI format for this address family consists of a fixed-length 904 Route Distinguisher field (8 bytes) followed by a flow specification, 905 following the encoding defined above in section x of this document. 906 The NLRI length field shall include both the 8 bytes of the Route 907 Distinguisher as well as the subsequent flow specification. 909 +------------------------------+ 910 | length (0xnn or 0xfn nn) | 911 +------------------------------+ 912 | Route Distinguisher (8 bytes)| 913 +------------------------------+ 914 | NLRI value (variable) | 915 +------------------------------+ 917 Figure 2: Flow-spec NLRI for MPLS 919 Propagation of this NLRI is controlled by matching Route Target 920 extended communities associated with the BGP path advertisement with 921 the VRF import policy, using the same mechanism as described in "BGP/ 922 MPLS IP VPNs" [RFC4364]. 924 Flow specification rules received via this NLRI apply only to traffic 925 that belongs to the VRF(s) in which it is imported. By default, 926 traffic received from a remote PE is switched via an MPLS forwarding 927 decision and is not subject to filtering. 929 Contrary to the behavior specified for the non-VPN NLRI, flow rules 930 are accepted by default, when received from remote PE routers. 932 8.1. Validation Procedures for BGP/MPLS VPNs 934 The validation procedures are the same as for IPv4. 936 8.2. Traffic Actions Rules 938 The traffic action rules are the same as for IPv4. 940 9. Limitations of Previous Traffic Filtering Efforts 942 9.1. Limitations in Previous DDOS Traffic Filtering Efforts 944 The popularity of traffic-based, denial-of-service (DoS) attacks, 945 which often requires the network operator to be able to use traffic 946 filters for detection and mitigation, brings with it requirements 947 that are not fully satisfied by existing tools. 949 Increasingly, DoS mitigation requires coordination among several 950 service providers in order to be able to identify traffic source(s) 951 and because the volumes of traffic may be such that they will 952 otherwise significantly affect the performance of the network. 954 Several techniques are currently used to control traffic filtering of 955 DoS attacks. Among those, one of the most common is to inject 956 unicast route advertisements corresponding to a destination prefix 957 being attacked. One variant of this technique marks such route 958 advertisements with a community that gets translated into a discard 959 Next-Hop by the receiving router. Other variants attract traffic to 960 a particular node that serves as a deterministic drop point. 962 Using unicast routing advertisements to distribute traffic filtering 963 information has the advantage of using the existing infrastructure 964 and inter-AS communication channels. This can allow, for instance, a 965 service provider to accept filtering requests from customers for 966 address space they own. 968 There are several drawbacks, however. An issue that is immediately 969 apparent is the granularity of filtering control: only destination 970 prefixes may be specified. Another area of concern is the fact that 971 filtering information is intermingled with routing information. 973 The mechanism defined in this document is designed to address these 974 limitations. We use the flow specification NLRI defined above to 975 convey information about traffic filtering rules for traffic that 976 should be discarded. 978 9.2. Limitations in Previous BGP/MPLS Traffic Monitoring 980 Provider-based Layer 3 VPN networks, such as the ones using a BGP/ 981 MPLS IP VPN [RFC4364] control plane, have different traffic filtering 982 requirements than Internet service providers. 984 In these environments, the VPN customer network often has traffic 985 filtering capabilities towards their external network connections 986 (e.g., firewall facing public network connection). Less common is 987 the presence of traffic filtering capabilities between different VPN 988 attachment sites. In an any-to-any connectivity model, which is the 989 default, this means that site-to-site traffic is unfiltered. 991 In circumstances where a security threat does get propagated inside 992 the VPN customer network, there may not be readily available 993 mechanisms to provide mitigation via traffic filter. 995 The BGP Flow Specification version 1 addresses these limitations. 997 10. Traffic Monitoring 999 Traffic filtering applications require monitoring and traffic 1000 statistics facilities. While this is an implementation-specific 1001 choice, implementations SHOULD provide: 1003 o A mechanism to log the packet header of filtered traffic. 1005 o A mechanism to count the number of matches for a given flow 1006 specification rule. 1008 11. IANA Considerations 1010 This section complies with [RFC7153] 1012 11.1. AFI/SAFI Definitions 1014 For the purpose of this work, IANA has allocated values for two 1015 SAFIs: SAFI 133 for IPv4 dissemination of flow specification rules 1016 and SAFI 134 for VPNv4 dissemination of flow specification rules. 1018 11.2. Flow Component definitions 1020 A flow specification consists of a sequence of flow components, which 1021 are identified by a an 8-bit component type. Types must be assigned 1022 and interpreted uniquely. The current specification defines types 1 1023 though 12, with the value 0 being reserved. 1025 IANA created and maintains a new registry entitled: "Flow Spec 1026 Component Types". The following component types have been 1027 registered: 1029 Type 1 - Destination Prefix 1031 Type 2 - Source Prefix 1033 Type 3 - IP Protocol 1035 Type 4 - Port 1037 Type 5 - Destination port 1039 Type 6 - Source port 1041 Type 7 - ICMP type 1043 Type 8 - ICMP code 1045 Type 9 - TCP flags 1047 Type 10 - Packet length 1049 Type 11 - DSCP 1051 Type 12 - Fragment 1053 Type 13 - Bit Mask filter 1055 In order to manage the limited number space and accommodate several 1056 usages, the following policies defined by RFC 5226 [RFC5226] are 1057 used: 1059 +--------------+-------------------------------+ 1060 | Range | Policy | 1061 +--------------+-------------------------------+ 1062 | 0 | Invalid value | 1063 | [1 .. 12] | Defined by this specification | 1064 | [13 .. 127] | Specification Required | 1065 | [128 .. 255] | First Come First Served | 1066 +--------------+-------------------------------+ 1068 The specification of a particular "flow component type" must clearly 1069 identify what the criteria used to match packets forwarded by the 1070 router is. This criteria should be meaningful across router hops and 1071 not depend on values that change hop-by-hop such as TTL or Layer 2 1072 encapsulation. 1074 The "traffic-action" extended community defined in this document has 1075 46 unused bits, which can be used to convey additional meaning. IANA 1076 created and maintains a new registry entitled: "Traffic Action 1077 Fields". These values should be assigned via IETF Review rules only. 1078 The following traffic-action fields have been allocated: 1080 47 Terminal Action 1082 46 Sample 1084 0-45 Unassigned 1086 11.3. Extended Community Flow Specification Actions 1088 The Extended Community FLow Specification Action types consists of 1089 two parts: BGP Transitive Extended Community types and a set of sub- 1090 types. 1092 IANA has updated the following "BGP Transitive Extended Community 1093 Types" registries to contain the values listed below: 1095 0x80 - Generic Transitive Experimental Use Extended Community Part 1096 1 (Sub-Types are defined in the "Generic Transitive Experimental 1097 Extended Community Part 1 Sub-Types" Registry) 1099 0x81 - Generic Transitive Experimental Use Extended Community Part 1100 2 (Sub-Types are defined in the "Generic Transitive Experimental 1101 Extended Community Part 2 Sub-Types" Registry) 1103 0x82 - Generic Transitive Experimental Use Extended Community Part 1104 3 (Sub-Types are defined in the "Generic Transitive Experimental 1105 Use Extended Community Part 3 Sub-Types" Registry) 1106 RANGE REGISTRATION PROCEDURE 1107 0x00-0xbf First Come First Served 1108 0xc0-0xff IETF Review 1110 SUB-TYPE VALUE NAME REFERENCE 1111 0x00-0x05 unassigned 1112 0x06 traffic-rate [this document] 1113 0x07 traffic-action [this document] 1114 0x08 Flow spec redirect IPv4 [RFC5575] [RFC7674] 1115 [this document] 1116 0x09 traffic-marking [this document] 1117 0x10-0xff Unassigned [this document] 1119 12. Security Considerations 1121 Inter-provider routing is based on a web of trust. Neighboring 1122 autonomous systems are trusted to advertise valid reachability 1123 information. If this trust model is violated, a neighboring 1124 autonomous system may cause a denial-of-service attack by advertising 1125 reachability information for a given prefix for which it does not 1126 provide service. 1128 As long as traffic filtering rules are restricted to match the 1129 corresponding unicast routing paths for the relevant prefixes, the 1130 security characteristics of this proposal are equivalent to the 1131 existing security properties of BGP unicast routing. 1133 Where it is not the case, this would open the door to further denial- 1134 of-service attacks. 1136 Enabling firewall-like capabilities in routers without centralized 1137 management could make certain failures harder to diagnose. For 1138 example, it is possible to allow TCP packets to pass between a pair 1139 of addresses but not ICMP packets. It is also possible to permit 1140 packets smaller than 900 or greater than 1000 bytes to pass between a 1141 pair of addresses, but not packets whose length is in the range 900- 1142 1000. Such behavior may be confusing and these capabilities should 1143 be used with care whether manually configured or coordinated through 1144 the protocol extensions described in this document. 1146 13. Original authors 1148 Barry Greene, MuPedro Marques, Jared Mauch, Danny McPherson, and 1149 Nischal Sheth were authors on [RFC5575], and therefore are 1150 contributing authors on this document. 1152 Note: Any original author of [RFC5575] who wants to work on this 1153 draft can be added as a co-author. 1155 14. Acknowledgements 1157 The authors would like to thank Yakov Rekhter, Dennis Ferguson, Chris 1158 Morrow, Charlie Kaufman, and David Smith for their comments for the 1159 comments on the original [RFC5575]. Chaitanya Kodeboyina helped 1160 design the flow validation procedure; and Steven Lin and Jim Washburn 1161 ironed out all the details necessary to produce a working 1162 implementation in the original [RFC5575]. 1164 Additional acknowledgements for this document will be included here. 1166 15. References 1168 15.1. Normative References 1170 [RFC0793] Postel, J., "Transmission Control Protocol", STD 7, 1171 RFC 793, DOI 10.17487/RFC0793, September 1981, 1172 . 1174 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 1175 Requirement Levels", BCP 14, RFC 2119, 1176 DOI 10.17487/RFC2119, March 1997, 1177 . 1179 [RFC2474] Nichols, K., Blake, S., Baker, F., and D. Black, 1180 "Definition of the Differentiated Services Field (DS 1181 Field) in the IPv4 and IPv6 Headers", RFC 2474, 1182 DOI 10.17487/RFC2474, December 1998, 1183 . 1185 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 1186 Border Gateway Protocol 4 (BGP-4)", RFC 4271, 1187 DOI 10.17487/RFC4271, January 2006, 1188 . 1190 [RFC4360] Sangli, S., Tappan, D., and Y. Rekhter, "BGP Extended 1191 Communities Attribute", RFC 4360, DOI 10.17487/RFC4360, 1192 February 2006, . 1194 [RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private 1195 Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February 1196 2006, . 1198 [RFC4760] Bates, T., Chandra, R., Katz, D., and Y. Rekhter, 1199 "Multiprotocol Extensions for BGP-4", RFC 4760, 1200 DOI 10.17487/RFC4760, January 2007, 1201 . 1203 [RFC4761] Kompella, K., Ed. and Y. Rekhter, Ed., "Virtual Private 1204 LAN Service (VPLS) Using BGP for Auto-Discovery and 1205 Signaling", RFC 4761, DOI 10.17487/RFC4761, January 2007, 1206 . 1208 [RFC4762] Lasserre, M., Ed. and V. Kompella, Ed., "Virtual Private 1209 LAN Service (VPLS) Using Label Distribution Protocol (LDP) 1210 Signaling", RFC 4762, DOI 10.17487/RFC4762, January 2007, 1211 . 1213 [RFC5226] Narten, T. and H. Alvestrand, "Guidelines for Writing an 1214 IANA Considerations Section in RFCs", BCP 26, RFC 5226, 1215 DOI 10.17487/RFC5226, May 2008, 1216 . 1218 [RFC5575] Marques, P., Sheth, N., Raszuk, R., Greene, B., Mauch, J., 1219 and D. McPherson, "Dissemination of Flow Specification 1220 Rules", RFC 5575, DOI 10.17487/RFC5575, August 2009, 1221 . 1223 [RFC5668] Rekhter, Y., Sangli, S., and D. Tappan, "4-Octet AS 1224 Specific BGP Extended Community", RFC 5668, 1225 DOI 10.17487/RFC5668, October 2009, 1226 . 1228 [RFC6241] Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed., 1229 and A. Bierman, Ed., "Network Configuration Protocol 1230 (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011, 1231 . 1233 [RFC6482] Lepinski, M., Kent, S., and D. Kong, "A Profile for Route 1234 Origin Authorizations (ROAs)", RFC 6482, 1235 DOI 10.17487/RFC6482, February 2012, 1236 . 1238 [RFC7153] Rosen, E. and Y. Rekhter, "IANA Registries for BGP 1239 Extended Communities", RFC 7153, DOI 10.17487/RFC7153, 1240 March 2014, . 1242 [RFC7223] Bjorklund, M., "A YANG Data Model for Interface 1243 Management", RFC 7223, DOI 10.17487/RFC7223, May 2014, 1244 . 1246 [RFC7606] Chen, E., Ed., Scudder, J., Ed., Mohapatra, P., and K. 1247 Patel, "Revised Error Handling for BGP UPDATE Messages", 1248 RFC 7606, DOI 10.17487/RFC7606, August 2015, 1249 . 1251 [RFC7674] Haas, J., Ed., "Clarification of the Flowspec Redirect 1252 Extended Community", RFC 7674, DOI 10.17487/RFC7674, 1253 October 2015, . 1255 15.2. Informative References 1257 [I-D.ietf-idr-bgp-flowspec-label] 1258 liangqiandeng, l., Hares, S., You, J., Raszuk, R., and d. 1259 danma@cisco.com, "Carrying Label Information for BGP 1260 FlowSpec", draft-ietf-idr-bgp-flowspec-label-00 (work in 1261 progress), June 2016. 1263 [I-D.ietf-idr-bgp-flowspec-oid] 1264 Uttaro, J., Filsfils, C., Smith, D., Alcaide, J., and P. 1265 Mohapatra, "Revised Validation Procedure for BGP Flow 1266 Specifications", draft-ietf-idr-bgp-flowspec-oid-03 (work 1267 in progress), March 2016. 1269 [I-D.ietf-idr-flow-spec-v6] 1270 McPherson, D., Raszuk, R., Pithawala, B., 1271 akarch@cisco.com, a., and S. Hares, "Dissemination of Flow 1272 Specification Rules for IPv6", draft-ietf-idr-flow-spec- 1273 v6-07 (work in progress), March 2016. 1275 [I-D.ietf-idr-flowspec-interfaceset] 1276 Litkowski, S., Simpson, A., Patel, K., and J. Haas, 1277 "Applying BGP flowspec rules on a specific interface set", 1278 draft-ietf-idr-flowspec-interfaceset-01 (work in 1279 progress), June 2016. 1281 [I-D.ietf-idr-flowspec-l2vpn] 1282 Weiguo, H., liangqiandeng, l., Litkowski, S., and S. 1283 Zhuang, "Dissemination of Flow Specification Rules for L2 1284 VPN", draft-ietf-idr-flowspec-l2vpn-04 (work in progress), 1285 May 2016. 1287 [I-D.ietf-idr-flowspec-mpls-match] 1288 Yong, L., Hares, S., liangqiandeng, l., and J. You, "BGP 1289 Flow Specification Filter for MPLS Label", draft-ietf-idr- 1290 flowspec-mpls-match-00 (work in progress), May 2016. 1292 [I-D.ietf-idr-flowspec-nvo3] 1293 Weiguo, H., Zhuang, S., Li, Z., and R. Gu, "Dissemination 1294 of Flow Specification Rules for NVO3", draft-ietf-idr- 1295 flowspec-nvo3-00 (work in progress), May 2016. 1297 [I-D.ietf-idr-flowspec-packet-rate] 1298 Eddy, W., Dailey, J., and G. Clark, "BGP Flow 1299 Specification Packet-Rate Action", draft-ietf-idr- 1300 flowspec-packet-rate-00 (work in progress), June 2016. 1302 [I-D.ietf-idr-wide-bgp-communities] 1303 Raszuk, R., Haas, J., Lange, A., Amante, S., Decraene, B., 1304 Jakma, P., and R. Steenbergen, "Wide BGP Communities 1305 Attribute", draft-ietf-idr-wide-bgp-communities-02 (work 1306 in progress), May 2016. 1308 [RFC4303] Kent, S., "IP Encapsulating Security Payload (ESP)", 1309 RFC 4303, DOI 10.17487/RFC4303, December 2005, 1310 . 1312 [RFC6074] Rosen, E., Davie, B., Radoaca, V., and W. Luo, 1313 "Provisioning, Auto-Discovery, and Signaling in Layer 2 1314 Virtual Private Networks (L2VPNs)", RFC 6074, 1315 DOI 10.17487/RFC6074, January 2011, 1316 . 1318 [RFC6483] Huston, G. and G. Michaelson, "Validation of Route 1319 Origination Using the Resource Certificate Public Key 1320 Infrastructure (PKI) and Route Origin Authorizations 1321 (ROAs)", RFC 6483, DOI 10.17487/RFC6483, February 2012, 1322 . 1324 Authors' Addresses 1326 Robert Raszuk 1327 Bloomberg LP 1328 731 Lexington Ave 1329 New York City, NY 10022 1330 USA 1332 Email: robert@raszuk.net 1334 Susan Hares 1335 Huawei 1336 7453 Hickory Hill 1337 Saline, MI 48176 1338 USA 1340 Email: shares@ndzh.com