idnits 2.17.1 draft-ietf-ccamp-asymm-bw-bidir-lsps-bis-03.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: ---------------------------------------------------------------------------- No issues found here. 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 (August 10, 2011) is 4643 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) -- Obsolete informational reference (is this intentional?): RFC 5467 (Obsoleted by RFC 6387) Summary: 0 errors (**), 0 flaws (~~), 1 warning (==), 2 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group A. Takacs 3 Internet-Draft Ericsson 4 Obsoletes: 5467 (if approved) L. Berger 5 Intended status: Standards Track LabN Consulting, L.L.C. 6 Expires: February 11, 2012 D. Caviglia 7 Ericsson 8 D. Fedyk 9 Alcatel-Lucent 10 J. Meuric 11 France Telecom Orange 12 August 10, 2011 14 GMPLS Asymmetric Bandwidth Bidirectional Label Switched Paths (LSPs) 15 draft-ietf-ccamp-asymm-bw-bidir-lsps-bis-03.txt 17 Abstract 19 This document defines a method for the support of GMPLS asymmetric 20 bandwidth bidirectional Label Switched Paths (LSPs). The presented 21 approach is applicable to any switching technology and builds on the 22 original Resource Reservation Protocol (RSVP) model for the transport 23 of traffic-related parameters. This document moves the experiment 24 documented in RFC 5467 to the standards track and obsoletes RFC 5467. 26 Status of this Memo 28 This Internet-Draft is submitted in full conformance with the 29 provisions of BCP 78 and BCP 79. 31 Internet-Drafts are working documents of the Internet Engineering 32 Task Force (IETF). Note that other groups may also distribute 33 working documents as Internet-Drafts. The list of current Internet- 34 Drafts is at http://datatracker.ietf.org/drafts/current/. 36 Internet-Drafts are draft documents valid for a maximum of six months 37 and may be updated, replaced, or obsoleted by other documents at any 38 time. It is inappropriate to use Internet-Drafts as reference 39 material or to cite them other than as "work in progress." 41 This Internet-Draft will expire on February 11, 2012. 43 Copyright Notice 45 Copyright (c) 2011 IETF Trust and the persons identified as the 46 document authors. All rights reserved. 48 This document is subject to BCP 78 and the IETF Trust's Legal 49 Provisions Relating to IETF Documents 50 (http://trustee.ietf.org/license-info) in effect on the date of 51 publication of this document. Please review these documents 52 carefully, as they describe your rights and restrictions with respect 53 to this document. Code Components extracted from this document must 54 include Simplified BSD License text as described in Section 4.e of 55 the Trust Legal Provisions and are provided without warranty as 56 described in the Simplified BSD License. 58 Table of Contents 60 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 61 1.1. Background . . . . . . . . . . . . . . . . . . . . . . . . 3 62 1.2. Approach Overview . . . . . . . . . . . . . . . . . . . . 4 63 1.3. Conventions Used in This Document . . . . . . . . . . . . 5 64 2. Generalized Asymmetric Bandwidth Bidirectional LSPs . . . . . 6 65 2.1. UPSTREAM_FLOWSPEC Object . . . . . . . . . . . . . . . . . 6 66 2.1.1. Procedures . . . . . . . . . . . . . . . . . . . . . . 6 67 2.2. UPSTREAM_TSPEC Object . . . . . . . . . . . . . . . . . . 6 68 2.2.1. Procedures . . . . . . . . . . . . . . . . . . . . . . 7 69 2.3. UPSTREAM_ADSPEC Object . . . . . . . . . . . . . . . . . . 7 70 2.3.1. Procedures . . . . . . . . . . . . . . . . . . . . . . 7 71 3. Packet Formats . . . . . . . . . . . . . . . . . . . . . . . . 8 72 4. Compatibility . . . . . . . . . . . . . . . . . . . . . . . . 10 73 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 11 74 5.1. UPSTREAM_FLOWSPEC Object . . . . . . . . . . . . . . . . . 11 75 5.2. UPSTREAM_TSPEC Object . . . . . . . . . . . . . . . . . . 11 76 5.3. UPSTREAM_ADSPEC Object . . . . . . . . . . . . . . . . . . 11 77 6. Security Considerations . . . . . . . . . . . . . . . . . . . 12 78 7. References . . . . . . . . . . . . . . . . . . . . . . . . . . 13 79 7.1. Normative References . . . . . . . . . . . . . . . . . . . 13 80 7.2. Informative References . . . . . . . . . . . . . . . . . . 13 81 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15 83 1. Introduction 85 GMPLS [RFC3473] introduced explicit support for bidirectional Label 86 Switched Paths (LSPs). The defined support matched the switching 87 technologies covered by GMPLS, notably Time Division Multiplexing 88 (TDM) and lambdas; specifically, it only supported bidirectional LSPs 89 with symmetric bandwidth allocation. Symmetric bandwidth 90 requirements are conveyed using the semantics objects defined in 91 [RFC2205] and [RFC2210]. 93 GMPLS asymmetric bandwidth bidirectional LSPs are bidirectional LSPs 94 that have different bandwidth reservations in each direction. 95 Support for bidirectional LSPs with asymmetric bandwidth, was 96 previously discussed in the context of Ethernet, notably [RFC6060] 97 and [RFC6003]. In that context, asymmetric bandwidth support was 98 considered to be a capability that was unlikely to be deployed, and 99 hence [RFC5467] was published as Experimental. The MPLS Transport 100 Profile, MPLS-TP, requires that asymmetric bandwidth bidirectional 101 LSPs be supported, see [RFC5654], and therefore this document is 102 being published on the Standards Track. This document has no 103 technical changes from the approach defined in [RFC5467]. This 104 document moves the experiment documented in [RFC5467] to the 105 standards track and obsoletes [RFC5467]. This document also removes 106 the Ethernet technology specific alternative approach discussed in 107 the appendix of [RFC5467] and maintains only one approach that is 108 suitable for use with any technology. 110 1.1. Background 112 Bandwidth parameters are transported within RSVP ([RFC2210], 113 [RFC3209], and [RFC3473]) via several objects that are opaque to 114 RSVP. While opaque to RSVP, these objects support a particular model 115 for the communication of bandwidth information between an RSVP 116 session sender (ingress) and receiver (egress). The original model 117 of communication, defined in [RFC2205] and maintained in [RFC3209], 118 used the SENDER_TSPEC and ADSPEC objects in Path messages and the 119 FLOWSPEC object in Resv messages. The SENDER_TSPEC object was used 120 to indicate a sender's data generation capabilities. The FLOWSPEC 121 object was issued by the receiver and indicated the resources that 122 should be allocated to the associated data traffic. The ADSPEC 123 object was used to inform the receiver and intermediate hops of the 124 actual resources available for the associated data traffic. 126 With the introduction of bidirectional LSPs in [RFC3473], the model 127 of communication of bandwidth parameters was implicitly changed. In 128 the context of [RFC3473] bidirectional LSPs, the SENDER_TSPEC object 129 indicates the desired resources for both upstream and downstream 130 directions. The FLOWSPEC object is simply confirmation of the 131 allocated resources. The definition of the ADSPEC object is either 132 unmodified and only has meaning for downstream traffic, or is 133 implicitly or explicitly ([RFC4606] and [RFC6003]) irrelevant. 135 1.2. Approach Overview 137 The approach for supporting asymmetric bandwidth bidirectional LSPs 138 defined in this document builds on the original RSVP model for the 139 transport of traffic-related parameters and GMPLS's support for 140 bidirectional LSPs. 142 The defined approach is generic and can be applied to any switching 143 technology supported by GMPLS. With this approach, the existing 144 SENDER_TSPEC, ADSPEC, and FLOWSPEC objects are complemented with the 145 addition of new UPSTREAM_TSPEC, UPSTREAM_ADSPEC, and 146 UPSTREAM_FLOWSPEC objects. The existing objects are used in the 147 original fashion defined in [RFC2205] and [RFC2210], and refer only 148 to traffic associated with the LSP flowing in the downstream 149 direction. The new objects are used in exactly the same fashion as 150 the old objects, but refer to the upstream traffic flow. Figure 1 151 shows the bandwidth-related objects used for asymmetric bandwidth 152 bidirectional LSPs. 154 |---| Path |---| 155 | I |------------------->| E | 156 | n | -SENDER_TSPEC | g | 157 | g | -ADSPEC | r | 158 | r | -UPSTREAM_FLOWSPEC | e | 159 | e | | s | 160 | s | Resv | s | 161 | s |<-------------------| | 162 | | -FLOWSPEC | | 163 | | -UPSTREAM_TSPEC | | 164 | | -UPSTREAM_ADSPEC | | 165 |---| |---| 167 Figure 1: Generic Asymmetric Bandwidth Bidirectional LSPs 169 The extensions defined in this document are limited to Point-to-Point 170 (P2P) LSPs. Support for Point-to-Multipoint (P2MP) bidirectional 171 LSPs is not currently defined and, as such, not covered in this 172 document. 174 1.3. Conventions Used in This Document 176 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 177 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 178 document are to be interpreted as described in [RFC2119]. 180 2. Generalized Asymmetric Bandwidth Bidirectional LSPs 182 The setup of an asymmetric bandwidth bidirectional LSP is signaled 183 using the bidirectional procedures defined in [RFC3473] together with 184 the inclusion of the new UPSTREAM_FLOWSPEC, UPSTREAM_TSPEC, and 185 UPSTREAM_ADSPEC objects. 187 The new upstream objects carry the same information and are used in 188 the same fashion as the existing downstream objects; they differ in 189 that they relate to traffic flowing in the upstream direction while 190 the existing objects relate to traffic flowing in the downstream 191 direction. The new objects also differ in that they are carried in 192 messages traveling in the opposite direction. 194 2.1. UPSTREAM_FLOWSPEC Object 196 The format of an UPSTREAM_FLOWSPEC object is the same as a FLOWSPEC 197 object [RFC2210]. This includes the definition of class types and 198 their formats. The class number of the UPSTREAM_FLOWSPEC object is 199 120 (of the form 0bbbbbbb). 201 2.1.1. Procedures 203 The Path message of an asymmetric bandwidth bidirectional LSP MUST 204 contain an UPSTREAM_FLOWSPEC object and MUST use the bidirectional 205 LSP formats and procedures defined in [RFC3473]. The C-Type of the 206 UPSTREAM_FLOWSPEC object MUST match the C-Type of the SENDER_TSPEC 207 object used in the Path message. The contents of the 208 UPSTREAM_FLOWSPEC object MUST be constructed using a format and 209 procedures consistent with those used to construct the FLOWSPEC 210 object that will be used for the LSP, e.g., [RFC2210] or [RFC4328]. 212 Nodes processing a Path message containing an UPSTREAM_FLOWSPEC 213 object MUST use the contents of the UPSTREAM_FLOWSPEC object in the 214 upstream label and the resource allocation procedure defined in 215 Section 3.1 of [RFC3473]. Consistent with [RFC3473], a node that is 216 unable to allocate a label or internal resources based on the 217 contents of the UPSTREAM_FLOWSPEC object MUST issue a PathErr message 218 with a "Routing problem/MPLS label allocation failure" indication. 220 2.2. UPSTREAM_TSPEC Object 222 The format of an UPSTREAM_TSPEC object is the same as a SENDER_TSPEC 223 object. This includes the definition of class types and their 224 formats. The class number of the UPSTREAM_TSPEC object is 121 (of 225 the form 0bbbbbbb). 227 2.2.1. Procedures 229 The UPSTREAM_TSPEC object describes the traffic flow that originates 230 at the egress. The UPSTREAM_TSPEC object MUST be included in any 231 Resv message that corresponds to a Path message containing an 232 UPSTREAM_FLOWSPEC object. The C-Type of the UPSTREAM_TSPEC object 233 MUST match the C-Type of the corresponding UPSTREAM_FLOWSPEC object. 234 The contents of the UPSTREAM_TSPEC object MUST be constructed using a 235 format and procedures consistent with those used to construct the 236 FLOWSPEC object that will be used for the LSP, e.g., [RFC2210] or 237 [RFC4328]. The contents of the UPSTREAM_TSPEC object MAY differ from 238 contents of the UPSTREAM_FLOWSPEC object based on application data 239 transmission requirements. 241 When an UPSTREAM_TSPEC object is received by an ingress, the ingress 242 MAY determine that the original reservation is insufficient to 243 satisfy the traffic flow. In this case, the ingress MAY tear down 244 the LSP and send a PathTear message. Alternatively, the ingress MAY 245 issue a Path message with an updated UPSTREAM_FLOWSPEC object to 246 modify the resources requested for the upstream traffic flow. This 247 modification might require the LSP to be re-routed, and in extreme 248 cases might result in the LSP being torn down when sufficient 249 resources are not available along the path of the LSP. 251 2.3. UPSTREAM_ADSPEC Object 253 The format of an UPSTREAM_ADSPEC object is the same as an ADSPEC 254 object. This includes the definition of class types and their 255 formats. The class number of the UPSTREAM_ADSPEC object is 122 (of 256 the form 0bbbbbbb). 258 2.3.1. Procedures 260 The UPSTREAM_ADSPEC object MAY be included in any Resv message that 261 corresponds to a Path message containing an UPSTREAM_FLOWSPEC object. 262 The C-Type of the UPSTREAM_TSPEC object MUST be consistent with the 263 C-Type of the corresponding UPSTREAM_FLOWSPEC object. The contents 264 of the UPSTREAM_ADSPEC object MUST be constructed using a format and 265 procedures consistent with those used to construct the ADSPEC object 266 that will be used for the LSP, e.g., [RFC2210] or [RFC6003]. The 267 UPSTREAM_ADSPEC object is processed using the same procedures as the 268 ADSPEC object and, as such, MAY be updated or added at transit nodes. 270 3. Packet Formats 272 This section presents the RSVP message-related formats as modified by 273 this section. This document modifies formats defined in [RFC2205], 274 [RFC3209], and [RFC3473]. See [RFC5511] for the syntax used by RSVP. 275 Unmodified formats are not listed. Three new objects are defined in 276 this section: 278 Object name Applicable RSVP messages 279 --------------- ------------------------ 280 UPSTREAM_FLOWSPEC Path, PathTear, PathErr, and Notify 281 (via sender descriptor) 282 UPSTREAM_TSPEC Resv, ResvConf, ResvTear, ResvErr, and 283 Notify (via flow descriptor list) 284 UPSTREAM_ADSPEC Resv, ResvConf, ResvTear, ResvErr, and 285 Notify (via flow descriptor list) 287 The format of the sender description for bidirectional asymmetric 288 LSPs is: 290 ::= 291 [ ] 292 [ ] 293 [ ] 294 [ ] 295 296 298 The format of the flow descriptor list for bidirectional asymmetric 299 LSPs is: 301 ::= 302 | 304 ::= 305 [ ] 306 307