idnits 2.17.1 draft-ietf-idr-bgp-enhanced-route-refresh-02.txt: Checking boilerplate required by RFC 5378 and the IETF Trust (see https://trustee.ietf.org/license-info): ---------------------------------------------------------------------------- No issues found here. Checking nits according to https://www.ietf.org/id-info/1id-guidelines.txt: ---------------------------------------------------------------------------- == The page length should not exceed 58 lines per page, but there was 5 longer pages, the longest (page 2) being 60 lines == It seems as if not all pages are separated by form feeds - found 0 form feeds but 6 pages Checking nits according to https://www.ietf.org/id-info/checklist : ---------------------------------------------------------------------------- No issues found here. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year -- The document date (June 17, 2012) is 4329 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: 0 errors (**), 0 flaws (~~), 3 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group K. Patel 3 Internet Draft E. Chen 4 Intended Status: Standards Track B. Venkatachalapathy 5 Expiration Date: December 18, 2012 Cisco Systems 6 June 17, 2012 8 Enhanced Route Refresh Capability for BGP-4 9 draft-ietf-idr-bgp-enhanced-route-refresh-02.txt 11 Status of this Memo 13 This Internet-Draft is submitted to IETF in full conformance with the 14 provisions of BCP 78 and BCP 79. 16 Internet-Drafts are working documents of the Internet Engineering 17 Task Force (IETF), its areas, and its working groups. Note that 18 other groups may also distribute working documents as Internet- 19 Drafts. 21 Internet-Drafts are draft documents valid for a maximum of six months 22 and may be updated, replaced, or obsoleted by other documents at any 23 time. It is inappropriate to use Internet-Drafts as reference 24 material or to cite them other than as "work in progress." 26 The list of current Internet-Drafts can be accessed at 27 http://www.ietf.org/1id-abstracts.html 29 The list of Internet-Draft Shadow Directories can be accessed at 30 http://www.ietf.org/shadow.html 32 This Internet-Draft will expire on December 18, 2012. 34 Copyright Notice 36 Copyright (c) 2012 IETF Trust and the persons identified as the 37 document authors. All rights reserved. 39 This document is subject to BCP 78 and the IETF Trust's Legal 40 Provisions Relating to IETF Documents 41 (http://trustee.ietf.org/license-info) in effect on the date of 42 publication of this document. Please review these documents 43 carefully, as they describe your rights and restrictions with respect 44 to this document. Code Components extracted from this document must 45 include Simplified BSD License text as described in Section 4.e of 46 the Trust Legal Provisions and are provided without warranty as 47 described in the Simplified BSD License. 49 draft-ietf-idr-bgp-enhanced-route-refresh-02.txt 51 Abstract 53 In this document we enhance the existing BGP route refresh mechanisms 54 to provide for the demarcation of the beginning and the ending of a 55 route refresh. The enhancement can be used to facilitate on-line, 56 non-disruptive consistency validations of BGP routing updates. 58 1. Introduction 60 It is sometimes necessary to perform routing consistency validations 61 such as checking for possible missing withdraws between BGP speakers 62 [RFC4271]. Currently such validations typically involve off-line, 63 manual operations which can be tedious and time consuming. 65 In this document we enhance the existing BGP route refresh mechanisms 66 [RFC2918] to provide for the demarcation of the beginning and the 67 ending of a route refresh (which refers to the complete re- 68 advertisement of the Adj-RIB-Out to a peer, subject to routing 69 policies). The enhancement can be used to facilitate on-line, non- 70 disruptive consistency validation of BGP routing updates. 72 1.1. Specification of Requirements 74 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 75 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 76 document are to be interpreted as described in [RFC2119]. 78 2. Protocol Extensions 80 The BGP protocol extensions introduced in this document include the 81 definition of a new BGP capability, named "Enhanced Route Refresh 82 Capability", and the specification of the message subtypes for the 83 ROUTE-REFRESH message. 85 2.1. Enhanced Route Refresh Capability 87 The "Enhanced Route Refresh Capability" is a new BGP capability 88 [RFC5492]. The Capability Code for this capability is specified in 89 the IANA Considerations section of this document. The Capability 90 Length field of this capability is zero. 92 By advertising this capability to a peer, a BGP speaker conveys to 93 the peer that the speaker supports the message subtypes for the 94 ROUTE-REFRESH message and the related procedures described in this 96 draft-ietf-idr-bgp-enhanced-route-refresh-02.txt 98 document. 100 2.2. Subtypes for ROUTE-REFRESH Message 102 The "Reserved" field of the ROUTE-REFRESH message specified in 103 [RFC2918] is re-defined as the "Message Subtype" with the following 104 values: 106 0 - Normal route refresh request [RFC2918] 107 with/without ORF [RFC5291] 108 1 - Demarcation of the beginning of a route refresh 109 2 - Demarcation of the ending of a route refresh 111 The use of the message subtypes is described in the Operations 112 section. 114 3. Operations 116 A BGP speaker that support the message subtypes for the ROUTE-REFRESH 117 message and the related procedures SHOULD advertise the "Enhanced 118 Route Refresh Capability". 120 The following procedures are applicable only if a BGP speaker has 121 received the "Enhanced Route Refresh Capability" from a peer. 123 Before the speaker starts a route refresh that is either initiated 124 locally, or in response to a "normal route refresh request" from the 125 peer, the speaker MUST send a ROUTE-REFRESH message with the 126 specified message subtype to mark the beginning of the route refresh. 127 After the speaker completes the re-advertisement of the entire Adj- 128 RIB-Out to the peer, it MUST send a ROUTE-REFRESH message with the 129 specified message subtype to mark the ending of the route refresh. 131 Conceptually the "entire ADJ-RIB-Out" for a peer in this section 132 refers to all the route entries in the "ADJ-RIB-Out" for the peer at 133 the start of the route refresh. When a route entry in the "ADJ-RIB- 134 Out" changes, the advertisement of the modified route entry (instead 135 of the snapshot entry) would suffice. 137 In processing a ROUTE-REFRESH message from a peer, the BGP speaker 138 MUST examine the "message subtype" field of the message and take the 139 appropriate actions. The BGP speaker SHALL use the demarcations of 140 the beginning and the ending of a route refresh to perform 141 consistency validations of the updates received from the peer. All 143 draft-ietf-idr-bgp-enhanced-route-refresh-02.txt 145 the routes that were not re-advertised in the route refresh MUST be 146 purged, and SHOULD be logged for further analysis. 148 4. Error Handling 150 This document defines a new NOTIFICATION error code: 152 Error Code Symbolic Name 154 ROUTE-REFRESH Message Error 156 The following error subcodes are defined as well: 158 Subcode Symbolic Name 160 1 Invalid Message Length 162 The error handling specified in this section is applicable only when 163 a BGP speaker has received the "Enhanced Route Refresh Capability" 164 from a peer. 166 When the BGP speaker detects an error while processing a ROUTE- 167 REFRESH message with a non-zero "Message Subtype" field, it MUST send 168 a NOTIFICATION message with Error Code "ROUTE-REFRESH Message Error". 169 The Data field of the NOTIFICATION message MUST contain the complete 170 ROUTE-REFRESH message. 172 If the length, excluding the fixed-size message header, of the ROUTE- 173 REFRESH message with Message Subtype 1 and 2 is not 4, then the error 174 subcode is set to "Invalid Message Length". 176 5. IANA Considerations 178 This document defines the Enhanced Route Refresh Capability for BGP. 179 The Capability Code 70 has been assigned by the IANA. 181 In addition, this document defines an NOTIFICATION error code and 182 several error subcodes for the ROUTE-REFRESH message. They need to 183 be registered with the IANA. 185 draft-ietf-idr-bgp-enhanced-route-refresh-02.txt 187 6. Security Considerations 189 This extension to BGP does not change the underlying security issues. 191 7. Acknowledgments 193 The authors would like to thank Pedro Marques, Pradosh Mohapatra, 194 Robert Raszuk, Pranav Mehta, and Shyam Sethuram for discussions and 195 review. The authors would like to thank Martin Djernaes, Jeff haas, 196 Ilya Varlashkin, Rob Shakir, Paul Jakma, Jie Dong, Qing Zeng, Albert 197 Tian, and Jakob Heitz for their review and comments. 199 8. Normative References 201 [RFC4271] Rekhter, Y., Ed., Li, T., Ed., and S. Hares, Ed., "A 202 Border Gateway Protocol 4 (BGP-4)", RFC 4271, January 203 2006. 205 [RFC2918] Chen, E., "Route Refresh Capability for BGP-4", 206 RFC 2918, September 2000. 208 [RFC5492] Scudder, J. and R. Chandra, "Capabilities Advertisement 209 with BGP-4", RFC 5492, February 2009. 211 [RFC5291] Chen, E., and Rekhter, Y., "Outbound Route Filtering 212 Capability for BGP-4", RFC 5291, August 2008. 214 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 215 Requirement Levels", BCP 14, RFC 2119, March 1997. 217 9. Authors' Addresses 219 Keyur Patel 220 Cisco Systems 222 Email: keyupate@cisco.com 224 Enke Chen 225 Cisco Systems 227 Email: enkechen@cisco.com 229 Balaji Venkatachalapathy 230 Cisco Systems 232 draft-ietf-idr-bgp-enhanced-route-refresh-02.txt 234 Email: bvenkata@cisco.com