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If these are example addresses, they should be changed. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (March 7, 2017) is 2607 days in the past. Is this intentional? Checking references for intended status: Proposed Standard ---------------------------------------------------------------------------- (See RFCs 3967 and 4897 for information about using normative references to lower-maturity documents in RFCs) No issues found here. Summary: 2 errors (**), 0 flaws (~~), 2 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 opsawg Z. Li, Ed. 3 Internet-Draft R. Gu, Ed. 4 Intended status: Standards Track China Mobile 5 Expires: September 8, 2017 J. Dong 6 Huawei Technologies 7 March 7, 2017 9 Export BGP community information in IP Flow Information Export (IPFIX) 10 draft-ietf-opsawg-ipfix-bgp-community-01 12 Abstract 14 This draft specifies an extension to the IPFIX information model 15 defined in [RFC7012] to export the BGP community [RFC1997] 16 information. Three information elements, bgpCommunity, 17 bgpSourceCommunityList and bgpDestinationCommunityList, are 18 introduced in this document to carry the BGP community information. 19 bgpCommunity, containing exactly one BGP community value, is used to 20 consist the list in bgpSourceCommunityList and 21 bgpDestinationCommunityList, which are corresponding to a specific 22 flow's source IP and destination IP respectively. 24 Status of This Memo 26 This Internet-Draft is submitted in full conformance with the 27 provisions of BCP 78 and BCP 79. 29 Internet-Drafts are working documents of the Internet Engineering 30 Task Force (IETF). Note that other groups may also distribute 31 working documents as Internet-Drafts. The list of current Internet- 32 Drafts is at http://datatracker.ietf.org/drafts/current/. 34 Internet-Drafts are draft documents valid for a maximum of six months 35 and may be updated, replaced, or obsoleted by other documents at any 36 time. It is inappropriate to use Internet-Drafts as reference 37 material or to cite them other than as "work in progress." 39 This Internet-Draft will expire on September 8, 2017. 41 Copyright Notice 43 Copyright (c) 2017 IETF Trust and the persons identified as the 44 document authors. All rights reserved. 46 This document is subject to BCP 78 and the IETF Trust's Legal 47 Provisions Relating to IETF Documents 48 (http://trustee.ietf.org/license-info) in effect on the date of 49 publication of this document. Please review these documents 50 carefully, as they describe your rights and restrictions with respect 51 to this document. Code Components extracted from this document must 52 include Simplified BSD License text as described in Section 4.e of 53 the Trust Legal Provisions and are provided without warranty as 54 described in the Simplified BSD License. 56 Table of Contents 58 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 59 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 60 3. BGP Community Information Elements . . . . . . . . . . . . . 4 61 3.1. bgpCommunity . . . . . . . . . . . . . . . . . . . . . . 4 62 3.2. bgpSourceCommunityList . . . . . . . . . . . . . . . . . 4 63 3.3. bgpDestinationCommunityList . . . . . . . . . . . . . . . 5 64 4. Security Considerations . . . . . . . . . . . . . . . . . . . 5 65 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 6 66 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 7 67 7. References . . . . . . . . . . . . . . . . . . . . . . . . . 7 68 7.1. Normative References . . . . . . . . . . . . . . . . . . 7 69 7.2. Informative References . . . . . . . . . . . . . . . . . 7 70 Appendix A. Application Example . . . . . . . . . . . . . . . . 8 71 A.1. Template Record . . . . . . . . . . . . . . . . . . . . . 8 72 A.2. Data Set . . . . . . . . . . . . . . . . . . . . . . . . 9 73 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 10 75 1. Introduction 77 IP Flow Information Export (IPFIX) [RFC7011] provides network 78 administrators with traffic flow information using the information 79 elements (IEs) defined in [IANA-IPFIX] registries. Based on the 80 traffic flow information, network administrators know the amount and 81 direction of the traffic in their network, then they can optimize 82 their network when needed. For example, they can steer some flows 83 from the congested links to the low utilized links. 85 [IANA-IPFIX] has already defined the following IEs for traffic flow 86 information exporting in different grain: sourceIPv4Address, 87 sourceIPv4Prefix, destinationIPv4Address, destinationIPv4Prefix, 88 bgpSourceAsNumber, bgpDestinationAsNumber, bgpNextHopIPv4Address, 89 etc. In some circumstances, however, especially when traffic 90 engineering and optimization are used in the Tier 1 or Tier 2 91 operators' backbone networks, traffic flow information based on these 92 IEs is not suitable. Flow information based on IP address or IP 93 prefix is much more mediculous. On the contrary, flow information 94 based on AS number is too coarse. BGP community [RFC1997], which 95 describes a group of routes sharing some common properties, is 96 preferablely used for fine granularity traffic engineering 98 [Community-TE] [RFC4384]. Unfortunately, [IANA-IPFIX] has no IE 99 defined for BGP community information, yet. 101 Flow information based on BGP community can be collected by a 102 mediator defined in [RFC6183]. Mediator is responsible for the 103 correlation between flow information and BGP community. However no 104 IEs are defined in [RFC6183] for exporting BGP community information 105 in IPFIX. Furthermore, to correlate the BGP community with the flow 106 information, mediator needs to learn BGP routes and lookup in the BGP 107 routing table to get the matching entry for the specific flow. 108 Neither BGP route learning nor routing table lookup is trivial for a 109 mediator. Mediator is mainly introduced to release the performance 110 requirement for the exporter [RFC5982]. In fact, to obtain the 111 information for BGP related IEs that have already been defined, such 112 as bgpSourceAsNumber, bgpDestinationAsNumber, and 113 bgpNextHopIPv4Address, etc, exporter has to hold the up-to-date BGP 114 routing table and look up in the BGP routing table. The exporter can 115 get the community information in the same procedure. So, getting BGP 116 community information adds no more requirement for exporter. Some 117 vendors have already implemented this feature in their exporters 118 using private IEs. So, exporter is RECOMMENDED to export the BGP 119 community information in IPFIX directly, other than the mediator. 121 This draft specifies an extension to the IPFIX information model 122 defined in [RFC7012] to export the BGP community information. Three 123 IEs, bgpCommunity, bgpSourceCommunityList and 124 bgpDestinationCommunityList, are introduced to complete this task. 125 bgpCommunity contains one BGP community value. 126 BgpSourceCommunityList consists of a list of bgpCommunity 127 corresponding with the source IP address of a specific flow, and 128 bgpDestinationCommunityList consists of a list of bgpCommunity 129 corresponding with the destination IP address of a specific flow. 131 BgpCommunity, bgpSourceCommunityList and bgpDestinationCommunityList 132 IEs are applicable for both IPv4 and IPv6 traffic. Both exporter and 133 mediator can use these three IEs to export BGP community information 134 in IPFIX. 136 2. Terminology 138 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 139 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 140 document are to be interpreted as described in [RFC2119]. 142 3. BGP Community Information Elements 144 In order to export BGP community information along with other flow 145 information defined by IPFIX, we need to introduce three new IEs. 146 One is bgpCommunity, which is used to identify that the value in this 147 IE is BGP community [RFC1997]. The other two are 148 bgpSourceCommunityList and bgpDestinationCommunityList. They both 149 are basicList [RFC6313] of bgpCommunity. bgpSourceCommunityList and 150 bgpDestinationCommunityList are used to export BGP community 151 information corresponding to a specific flow's source IP and 152 destination IP respectively. Flow information based on BGP community 153 can then be accumulated and analysed by the collector or other 154 applications. 156 The details of these three new introduced IEs are illustrated below, 157 including name, ID, type, semantics, description and units. 159 3.1. bgpCommunity 161 ---------------------------------------------------------------------- 162 | ElementID | to be assigned by IANA, 458 is suggested | 163 ---------------------------------------------------------------------- 164 | Name | bgpCommunity | 165 |--------------------------------------------------------------------- 166 | Data Type | unsigned32 | 167 |--------------------------------------------------------------------- 168 | Data Type Semantics | identifier | 169 ---------------------------------------------------------------------- 170 | Description | BGP community as defined in [RFC1997] | 171 ---------------------------------------------------------------------- 172 | Units | none | 173 |--------------------------------------------------------------------- 175 Figure 1: bgpCommunity 177 3.2. bgpSourceCommunityList 178 ---------------------------------------------------------------------- 179 | ElementID | to be assigned by IANA, 459 is suggested | 180 ---------------------------------------------------------------------- 181 | Name | bgpSourceCommunityList | 182 |--------------------------------------------------------------------- 183 | Data Type | basicList, as specified in [RFC6313] | 184 |--------------------------------------------------------------------- 185 | Data Type Semantics | list | 186 ---------------------------------------------------------------------- 187 | Description | zero or more BGP communities corresponding | 188 | | with source IP address of a specific flow | 189 ---------------------------------------------------------------------- 190 | Units | none | 191 |--------------------------------------------------------------------- 193 Figure 2: bgpSourceCommunityList 195 3.3. bgpDestinationCommunityList 197 ---------------------------------------------------------------------- 198 | ElementID | to be assigned by IANA, 460 is suggested | 199 ---------------------------------------------------------------------- 200 | Name | bgpDestinationCommunityList | 201 |--------------------------------------------------------------------- 202 | Data Type | basicList, as specified in [RFC6313] | 203 |--------------------------------------------------------------------- 204 | Data Type Semantics | list | 205 ---------------------------------------------------------------------- 206 | Description | zero or more BGP communities corresponding | 207 | |with destination IP address of a specific flow| 208 ---------------------------------------------------------------------- 209 | Units | none | 210 |--------------------------------------------------------------------- 212 Figure 3: bgpDestinationCommunityList 214 4. Security Considerations 216 This document only defines three new IEs for IPFIX. So, this 217 document itself does not directly introduce security issues. The 218 same security considerations as for the IPFIX Protocol Specification 219 [RFC7011] and Information Model [RFC7012] apply. 221 As the BGP community information is deducible by other means, there 222 are no increased privacy concerns. 224 5. IANA Considerations 226 This draft specifies three new IPFIX IEs, bgpCommunity, 227 bgpSourceCommunityList and bgpDestinationCommunityList, to export BGP 228 community information along with other flow information. 230 The Element IDs for these three IEs are solicited to be assigned by 231 IANA. The following table is for IANA's reference to put in each 232 field in the registry. 234 ---------------------------------------------------------------------- 235 |ElementID| Name | Data Type|Data Type Semantics| 236 ---------------------------------------------------------------------- 237 | TBA1 | bgpCommunity |unsigned32| identifier | 238 |--------------------------------------------------------------------- 239 | TBA2 | bgpSourceCommunityList | basicList| list | 240 |--------------------------------------------------------------------- 241 | TBA3 |bgpDestinationCommunityList| basicList| list | 242 ---------------------------------------------------------------------- 244 ---------------------------------------------------------------------- 245 |ElementID| Description | Units | 246 ---------------------------------------------------------------------- 247 | TBA1 | BGP community | | 248 |--------------------------------------------------------------------- 249 | TBA2 | zero or more BGP communities corresponding | | 250 | | with source IP address of a specific flow | | 251 |--------------------------------------------------------------------- 252 | TBA3 | zero or more BGP communities corresponding | | 253 | |with destination IP address of a specific flow| | 254 ---------------------------------------------------------------------- 256 ---------------------------------------------------------------------- 257 |ElementID| Range | References | Requester | Revision | date | 258 ---------------------------------------------------------------------- 259 | TBA1 | | RFC1997 |this draft | 0 | | 260 |--------------------------------------------------------------------- 261 | TBA2 | |RFC6313,RFC1997|this draft | 0 | | 262 |--------------------------------------------------------------------- 263 | TBA3 | |RFC6313,RFC1997|this draft | 0 | | 264 ---------------------------------------------------------------------- 266 Figure 4 268 6. Acknowledgements 270 The authors would like to thank Benoit Claise and Paul Aitken for 271 their comments and suggestions to promote this document. 272 Appreciations are given to Tianran Zhou, Jeffrey Haas, Ignas 273 Bagdonas, Stewart Bryant, Paolo Lucente, Job Snijders, Jared Mauch, 274 etc, for their discussion in the mail list. 276 7. References 278 7.1. Normative References 280 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 281 Requirement Levels", BCP 14, RFC 2119, 282 DOI 10.17487/RFC2119, March 1997, 283 . 285 [RFC6313] Claise, B., Dhandapani, G., Aitken, P., and S. Yates, 286 "Export of Structured Data in IP Flow Information Export 287 (IPFIX)", RFC 6313, DOI 10.17487/RFC6313, July 2011, 288 . 290 [RFC7011] Claise, B., Ed., Trammell, B., Ed., and P. Aitken, 291 "Specification of the IP Flow Information Export (IPFIX) 292 Protocol for the Exchange of Flow Information", STD 77, 293 RFC 7011, DOI 10.17487/RFC7011, September 2013, 294 . 296 [RFC7012] Claise, B., Ed. and B. Trammell, Ed., "Information Model 297 for IP Flow Information Export (IPFIX)", RFC 7012, 298 DOI 10.17487/RFC7012, September 2013, 299 . 301 7.2. Informative References 303 [Community-TE] 304 Shao, W., Devienne, F., Iannone, L., and JL. Rougier, "On 305 the use of BGP communities for fine-grained inbound 306 traffic engineering", Computer Science 27392(1):476-487, 307 November 2015. 309 [IANA-IPFIX] 310 "IP Flow Information Export (IPFIX) Entities", 311 . 313 [RFC1997] Chandra, R., Traina, P., and T. Li, "BGP Communities 314 Attribute", RFC 1997, DOI 10.17487/RFC1997, August 1996, 315 . 317 [RFC4384] Meyer, D., "BGP Communities for Data Collection", BCP 114, 318 RFC 4384, DOI 10.17487/RFC4384, February 2006, 319 . 321 [RFC5982] Kobayashi, A., Ed. and B. Claise, Ed., "IP Flow 322 Information Export (IPFIX) Mediation: Problem Statement", 323 RFC 5982, DOI 10.17487/RFC5982, August 2010, 324 . 326 [RFC6183] Kobayashi, A., Claise, B., Muenz, G., and K. Ishibashi, 327 "IP Flow Information Export (IPFIX) Mediation: Framework", 328 RFC 6183, DOI 10.17487/RFC6183, April 2011, 329 . 331 Appendix A. Application Example 333 In this section, we give an example to show the encoding format for 334 the three new introduced IEs. 336 Flow information including BGP communities is shown in the below 337 table. Suppose we want all the fields to be reported by IPFIX. 339 -------------------------------------------------------------------------- 340 |Source ip|Destination ip |Source BGP community|Destination BGP community| 341 -------------------------------------------------------------------------- 342 | 1.1.1.1 | 2.2.2.2 |1:1001,1:1002,8:1001| 2:1002,8:1001 | 343 -------------------------------------------------------------------------- 344 | 3.3.3.3 | 4.4.4.4 |3:1001,3:1002,8:1001| 4:1001,8:1001 | 345 -------------------------------------------------------------------------- 347 Figure 5: Flow information including BGP communities 349 A.1. Template Record 350 0 1 2 3 351 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 352 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 353 | SET ID = 2 | Length = 24 | 354 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 355 | Template ID = 256 | Field Count = 4 | 356 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 357 |0| SourceIPv4Address = 8 | Field length = 4 | 358 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 359 |0| DestinationIPv4Address = 12 | Field length = 4 | 360 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 361 |0| bgpSourceCommunityList = 459| Field length = 0xFFFF | 362 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 363 |0| bgpDestinationCommunityList | Field length = 0xFFFF | 364 | | = 460 | | 365 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 367 Figure 6: Template Record Encoding Format 369 In this example, the Template ID is 256, which will be used in the 370 data record. The field length for bgpSourceCommunityList and 371 bgpDestinationCommunityList is 0xFFFF, which means the length of this 372 IE is variable, the actual length of this IE is indicated by the list 373 length field in the basic list format as per [RFC6313]. 375 A.2. Data Set 377 The data set is represented as follows: 379 0 1 2 3 380 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 381 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 382 | SET ID = 256 | Length = 92 | 383 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 384 | SourceIPv4Address = 1.1.1.1 | 385 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 386 | DestinationIPv4Address = 2.2.2.2 | 387 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 388 | 255 | List length = 17 |semantic=allof | 389 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 390 | bgpCommunity = 458 | Field Len = 4 | 391 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 392 | BGP Source Community Value 1 = 1:1001 | 393 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 394 | BGP Source Community Value 2 = 1:1002 | 395 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 396 | BGP Source Community Value 3 = 8:1001 | 397 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 398 | 255 | List length = 13 |semantic =allof| 399 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 400 | bgpCommunity = 458 | Field Len = 4 | 401 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 402 | BGP Destination Community Value 1 = 2:1002 | 403 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 404 | BGP Destination Community Value 2 = 8:1001 | 405 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 406 | SourceIPv4Address = 3.3.3.3 | 407 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 408 | DestinationIPv4Address = 4.4.4.4 | 409 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 410 | 255 | List length = 17 |semantic =allof| 411 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 412 | bgpCommunity = 458 | Field Len = 4 | 413 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 414 | BGP Source Community Value 1 = 3:1001 | 415 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 416 | BGP Source Community Value 2 = 3:1002 | 417 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 418 | BGP Source Community Value 3 = 8:1001 | 419 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 420 | 255 | List length = 13 |semantic =allof| 421 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 422 | bgpCommunity = 458 | Field Len = 4 | 423 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 424 | BGP Destination Community Value 1 = 4:1001 | 425 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 426 | BGP Destination Community Value 2 = 8:1001 | 427 +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 429 Figure 7: Data Set Encoding Format 431 Authors' Addresses 433 Zhenqiang Li (editor) 434 China Mobile 435 32 Xuanwumen West Ave, Xicheng District 436 Beijing 100053 437 China 439 Email: lizhenqiang@chinamobile.com 440 Rong Gu (editor) 441 China Mobile 442 32 Xuanwumen West Ave, Xicheng District 443 Beijing 100053 444 China 446 Email: gurong_cmcc@outlook.com 448 Jie Dong 449 Huawei Technologies 450 Huawei Campus, No. 156 Beiqing Rd. 451 Beijing 100095 452 China 454 Email: jie.dong@huawei.com