idnits 2.17.1 draft-zzhang-l3vpn-mvpn-bidir-ingress-replication-01.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 : ---------------------------------------------------------------------------- -- The draft header indicates that this document updates RFC6514, but the abstract doesn't seem to mention this, which it should. Miscellaneous warnings: ---------------------------------------------------------------------------- == The copyright year in the IETF Trust and authors Copyright Line does not match the current year (Using the creation date from RFC6514, updated by this document, for RFC5378 checks: 2006-08-01) -- The document seems to lack a disclaimer for pre-RFC5378 work, but may have content which was first submitted before 10 November 2008. If you have contacted all the original authors and they are all willing to grant the BCP78 rights to the IETF Trust, then this is fine, and you can ignore this comment. If not, you may need to add the pre-RFC5378 disclaimer. (See the Legal Provisions document at https://trustee.ietf.org/license-info for more information.) -- The document date (October 21, 2013) is 3840 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) == Unused Reference: 'RFC5015' is defined on line 300, but no explicit reference was found in the text == Unused Reference: 'I-D.ietf-l3vpn-mvpn-bidir' is defined on line 304, but no explicit reference was found in the text == Outdated reference: A later version (-08) exists of draft-ietf-l3vpn-mvpn-bidir-06 Summary: 0 errors (**), 0 flaws (~~), 4 warnings (==), 3 comments (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group Zhang 3 Internet-Draft Rekhter 4 Updates: 6514 (if approved) Juniper Networks 5 Intended status: Standards Track Dolganow 6 Expires: April 24, 2014 Alcatel-Lucent 7 October 21, 2013 9 Simulating "Partial Mesh of MP2MP P-Tunnels" with Ingress Replication 10 draft-zzhang-l3vpn-mvpn-bidir-ingress-replication-01.txt 12 Abstract 14 RFC 6513 described a method to support bidirectional C-flow using 15 "Partial Mesh of MP2MP P-Tunnels". This document describes how 16 partial mesh of MP2MP P-Tunnels can be simulated with Ingress 17 Replication, instead of a real MP2MP tunnel. This enables a Service 18 Provider to use Ingress Replication to offer transparent BIDIR-PIM 19 service to its VPN customers. 21 Status of this Memo 23 This Internet-Draft is submitted in full conformance with the 24 provisions of BCP 78 and BCP 79. 26 Internet-Drafts are working documents of the Internet Engineering 27 Task Force (IETF). Note that other groups may also distribute 28 working documents as Internet-Drafts. The list of current Internet- 29 Drafts is at http://datatracker.ietf.org/drafts/current/. 31 Internet-Drafts are draft documents valid for a maximum of six months 32 and may be updated, replaced, or obsoleted by other documents at any 33 time. It is inappropriate to use Internet-Drafts as reference 34 material or to cite them other than as "work in progress." 36 This Internet-Draft will expire on April 24, 2014. 38 Copyright Notice 40 Copyright (c) 2013 IETF Trust and the persons identified as the 41 document authors. All rights reserved. 43 This document is subject to BCP 78 and the IETF Trust's Legal 44 Provisions Relating to IETF Documents 45 (http://trustee.ietf.org/license-info) in effect on the date of 46 publication of this document. Please review these documents 47 carefully, as they describe your rights and restrictions with respect 48 to this document. Code Components extracted from this document must 49 include Simplified BSD License text as described in Section 4.e of 50 the Trust Legal Provisions and are provided without warranty as 51 described in the Simplified BSD License. 53 Table of Contents 55 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . . 3 56 1.1. Terminology . . . . . . . . . . . . . . . . . . . . . . . 3 57 2. Requirements Language . . . . . . . . . . . . . . . . . . . . 4 58 3. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . 5 59 3.1. Control State . . . . . . . . . . . . . . . . . . . . . . 5 60 3.2. Forwarding State . . . . . . . . . . . . . . . . . . . . . 7 61 4. Security Considerations . . . . . . . . . . . . . . . . . . . 9 62 5. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 10 63 6. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 11 64 7. Normative References . . . . . . . . . . . . . . . . . . . . . 12 65 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 13 67 1. Introduction 69 Section 11.2 of RFC 6513, "Partitioned Sets of PEs", describes two 70 methods of carrying bidirectional C-flow traffic over a provider core 71 without using the core as RPL or requiring Designated Forwarder 72 election. 74 With these two methods, all PEs of a particular VPN are separated 75 into partitions, with each partition being all the PEs that elect the 76 same PE as the Upstream PE wrt the C-RPA. A PE must discard 77 bidirectional C-flow traffic from PEs that are not in the same 78 partition as the PE itself. 80 In particular, Section 11.2.3 of RFC 6513, "Partial Mesh of MP2MP 81 P-Tunnels", guarantees the above discard behavior without using an 82 extra PE Distinguisher label by having all PEs in the same partition 83 join a single MP2MP tunnel dedicated to that partition and use it to 84 transmit traffic. All traffic arriving on the tunnel will be from 85 PEs in the same partition, so it will be always accepted. 87 RFC 6514 specifies BGP encodings and procedures used to implement 88 MVPN as specified in RFC 6513, while the details related to MP2MP 89 tunnels are specified in [draft-ietf-l3vpn-mvpn-bidir-05]. 91 [draft-ietf-l3vpn-mvpn-bidir-05] assumes that an MP2MP P-tunnel is 92 realized either via PIM-Bidir, or via MP2MP mLDP. Each of them would 93 require signaling and state not just on PEs, but on the P routers as 94 well. This document describes how the MP2MP tunnel can be simulated 95 with a mesh of P2MP tunnels, each of which is instantiated by Ingress 96 Replication. This does not require each PE on the MP2MP tunnel to 97 send an S-PMSI A-D route for the P2MP tunnel that the PE is the root 98 for, nor does it require each PE to send a Leaf A-D route to the root 99 of each P2MP tunnel in the mesh. 101 With the use of Ingress Replication,this scheme has both the 102 advantages and the disadvantages of Ingress Replication in general. 104 1.1. Terminology 106 This document uses terminology from [RFC6513], [RFC6514], and 107 [draft-ietf-l3vpn-mvpn-bidir-05]. In particular, the following new 108 term is defined: 110 o C-G-BIDIR: A C-G where G is a Bidir-PIM group. 112 2. Requirements Language 114 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 115 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 116 document are to be interpreted as described in [RFC2119]. 118 3. Operation 120 In following sections, the originator of an S-PMSI A-D route or Leaf 121 A-D route is determined from the "originating router's IP address" 122 field of the corresponding route. 124 3.1. Control State 126 If a PE, say PEx, is connected to a site of a given VPN, and PEx's 127 next hop interface to some C-RPA is a VRF interface, then PEx MUST 128 advertises a (C-*,C-BIDIR) S-PMSI A-D route, regardless of whether it 129 has any local Bidir-PIM join states corresponding to the C-RPA 130 learned from its CEs. It MAY also advertise one or more (C-*,C-G- 131 BIDIR) S-PMSI A-D route, just like how any other S-PMSI A-D routes 132 are triggered. Here the C-G-BIDIR refers to a C-G where G is a 133 Bidir-PIM group, and the corresponding C-RPA is in the site that the 134 PEx connects to. For example, the (C-*,C-G-BIDIR) S-PMSI A-D routes 135 could be triggered when the (C-*, C-G-BIDIR) traffic rate goes above 136 a threshold, and fan-out could also be taken into account. Note that 137 this requires measuring the traffic in both directions, due to the 138 nature of Bidir-PIM. 140 The S-PMSI A-D routes include a PMSI Tunnel Attribute (PTA) with 141 tunnel type set to Ingress Replication, with Leaf Information 142 Required flag set, with a downstream allocated MPLS label that other 143 PEs in the same partition MUST use when sending relevant C-bidir 144 flows to this PE, and with the Tunnel Identifier field in the PTA set 145 to a routable address of the originator. The label may be shared 146 with other P-tunnels, subject to the anti-ambiguity rules for 147 extranet. For example, the (C-*,C-BIDIR) and (C-*,C-G-BIDIR) S-PMSI 148 A-D routes originated by a given PE can optionally share a label. 150 If some other PE, PEy, receives and imports into one of its VRFs any 151 (C-*, C-BIDIR) S-PMSI A-D route whose PTA specifies an IR P-tunnel, 152 and the VRF has any local Bidir-PIM join state that PEy has received 153 from its CEs, and if PEy chooses PEx as its Upstream PE wrt the C-RPA 154 for those states, PEy MUST advertise a Leaf A-D route in response. 155 Or, if PEy has received and imported into one of its VRFs a (C-*,C- 156 BIDIR) S-PMSI A-D route from PEx before, then upon receiving in the 157 VRF any local Bidir-PIM join state from its CEs with PEx being the 158 Upstream PE for those states' C-RPA, PEy MUST advertise a Leaf A-D 159 route. 161 The encoding of the Leaf A-D route is as specified in RFC 6514, 162 except that the Route Targets are set to the same value as in the 163 corresponding S-PMSI A-D route so that the Leaf A-D route will be 164 imported by all VRFs that import the corresponding S-PMSI A-D route. 165 This is irrespective of whether from a receiving PE, PEz's 166 perspective PEx (originator of the S-PMSI A-D route) is the Upstream 167 PE or not. The label in the PTA of the Leaf A-D route originated by 168 PEy MUST be allocated specifically for PEx, so that when traffic 169 arrives with that label, the traffic can associated with the 170 partition (represented by the PEx). The label may be shared with 171 other P-tunnels, subject to the anti-ambiguity rules for extranet. 172 For example, the (C-*,C-BIDIR) and (C-*,C-G-BIDIR) S-PMSI A-D routes 173 originated by a given PE can optionally share a label. 175 Note that RFC 6514 requires a PE/ASBR take no action with regard to a 176 Leaf A-D route unless that Leaf A-D route carries an IP Address 177 Specific RT identifying the PE/ASBR. This document removes that 178 requirement when the route key of a Leaf A-D route identifies a 179 (C-*,C-BIDIR) or a (C-*,C-G-BIDIR) S-PMSI. 181 To speed up convergence (so that PEy starts receiving traffic from 182 its new Upstream PE immediately instead of waiting until the new Leaf 183 A-D route corresponding to the new Upstream PE is received by sending 184 PEs), PEy MAY advertise a Leaf A-D route even if does not choose PEx 185 as its Upstream PE wrt the C-RPA. With that, it will receive traffic 186 from all PEs, but some will arrive with the label corresponding to 187 its choice of Upstream PE while some will arrive with a different 188 label, and the traffic in the latter case will be discarded. 190 Similar to the (C-*,C-BIDIR) case, if PEy receives and imports into 191 one of its VRFs any (C-*,C-G-BIDIR) S-PMSI A-D route whose PTA 192 specifies an IR P-tunnel, and PEy chooses PEx as its Upstream PE wrt 193 the C-RPA, and it has corresponding local (C-*,C-G-BIDIR) join state 194 that it has received from its CEs in the VRF, PEy MUST advertise a 195 Leaf A-D route in response. Or, if PEy has received and imported 196 into one of its VRFs a (C-*,C-G-BIDIR) S-PMSI A-D route before, then 197 upon receiving its local (C-*,C-G-BIDIR) join state from its CEs in 198 the VRF, it MUST advertise a Leaf A-D route. 200 The encoding of the Leaf A-D route is as specified in RFC 6514, 201 except that the Route Targets are set to the same as in the 202 corresponding S-PMSI A-D route so that the Leaf A-D route will be 203 imported by all VRFs that import the corresponding S-PMSI A-D route. 204 This is irrespective of whether from the receiving PE, PEz's 205 perspective PEx (originator of the S-PMSI A-D route) is the Upstream 206 PE or not. The label in the PTA of the Leaf A-D route originated by 207 PEy MUST be allocated specifically for PEx, so that when traffic 208 arrives with that label, the traffic can associated with the 209 partition (represented by the PEx). The label may be shared with 210 other P-tunnels, subject to the anti-ambiguity rules for extranet. 211 For example, the (C-*,C-BIDIR) and (C-*,C-G-BIDIR) S-PMSI A-D routes 212 originated by a given PE can optionally share a label. 214 Whenever the (C-*,C-BIDIR) or (C-*,C-G-BIDIR) S-PMSI A-D route is 215 withdrawn, or if PEy no longer chooses the originator PEx as its 216 Upstream PE wrt C-RPA and PEy only advertises Leaf A-D routes in 217 response to its Upstream PE's S-PMSI A-D route, or if relevant local 218 join state is pruned, PEy MUST withdraw the corresponding Leaf A-D 219 route. 221 3.2. Forwarding State 223 The following specification regarding forwarding state matches the 224 "When an S-PMSI is a 'Match for Transmission'" and "When an S-PMSI is 225 a 'Match for Reception'" rules for "Flat Partitioning" method in 226 [draft-ietf-l3vpn-mvpn-bidir-05], except that the rules about 227 (C-*,C-*) are not applicable, because this document requires that 228 (C-*,C-BIDIR) S-PMSI A-D routes are always originated for a VPN that 229 supports C-Bidir flows. 231 For the (C-*,C-G-BIDIR) S-PMSI A-D route that a PEy receives and 232 imports into one of its VRFs from its Upstream PE wrt the C-RPA, or 233 if PEy itself advertises the S-PMSI A-D route in the VRF, PEy 234 maintains a (C-*,C-G-BIDR) forwarding state in the VRF, with the 235 Ingress Replication provider tunnel leaves being the originators of 236 the S-PMSI A-D route and all relevant Leaf-A-D routes. The relevant 237 Leaf A-D routes are the routes whose Route Key field contains the 238 same information as the MCAST-VPN NLRI of the (C-*, C-G-BIDIR) S-PMSI 239 A-D route advertised by the Upstream PE. 241 For the (C-*,C-BIDIR) S-PMSI A-D route that a PEy receives and 242 imports into one of its VRFs from its Upstream PE wrt a C-RPA, or if 243 PEy itself advertises the S-PMSI A-D route in the VRF, it maintains 244 appropriate forwarding states in the VRF for the ranges of 245 bidirectional groups for which the C-RPA is responsible. The 246 provider tunnel leaves are the originators of the S-PMSI A-D route 247 and all relevant Leaf-A-D routes. The relevant Leaf A-D routes are 248 the routes whose Route Key field contains the same information as the 249 MCAST-VPN NLRI of the (C-*, C-BIDIR) S-PMSI A-D route advertised by 250 the Upstream PE. This is for the so-called "Sender Only Branches" 251 where a router only has data to send upstream towards C-RPA but no 252 explicit join state for a particular bidirectional group. Note that 253 the traffic must be sent to all PEs (not just the Upstream PE) in the 254 partition, because they may have specific (C-*,C-G-BIDIR) join states 255 that this PEy is not aware of, while there is no corresponding 256 (C-*,C-G-BIDIR) S-PMSI A-D and Leaf A-D routes. 258 For a (C-*,C-G-BIDIR) join state that a PEy has received from its CEs 259 in a VRF, if there is no corresponding (C-*,C-G-BIDIR) S-PMSI A-D 260 route from its Upstream PE in the VRF, PEy maintains a corresponding 261 forwarding state in the VRF, with the provider tunnel leaves being 262 the originators of the (C-*,C-BIDIR) S-PMSI A-D route and all 263 relevant Leaf-A-D routes (same as the above Sender Only Branch case). 264 The relevant Leaf A-D routes are the routes whose Route Key field 265 contains the same information as the MCAST-VPN NLRI of the (C-*, 266 C-BIDIR) S-PMSI A-D route originated by the Upstream PE. If there is 267 no (C-*,C-BIDIR) S-PMSI A-D route from its Upstream PE either, then 268 the provider tunnel has an empty set of leaves and PEy does not 269 forward relevant traffic across the provider network. 271 4. Security Considerations 273 This document raises no new security issues. Security considerations 274 for the base protocol are covered in [RFC6514]. 276 5. IANA Considerations 278 This document has no IANA considerations. 280 This section should be removed by the RFC Editor prior to final 281 publication. 283 6. Acknowledgements 285 We would like to thank Eric Rosen for his comments, and suggestions 286 of some texts used in the document. 288 7. Normative References 290 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 291 Requirement Levels", BCP 14, RFC 2119, March 1997. 293 [RFC6513] Rosen, E. and R. Aggarwal, "Multicast in MPLS/BGP IP 294 VPNs", RFC 6513, February 2012. 296 [RFC6514] Aggarwal, R., Rosen, E., Morin, T., and Y. Rekhter, "BGP 297 Encodings and Procedures for Multicast in MPLS/BGP IP 298 VPNs", RFC 6514, February 2012. 300 [RFC5015] Handley, M., Kouvelas, I., Speakman, T., and L. Vicisano, 301 "Bidirectional Protocol Independent Multicast (BIDIR- 302 PIM)", RFC 5015, October 2007. 304 [I-D.ietf-l3vpn-mvpn-bidir] 305 Rosen, E., Wijnands, I., Cai, Y., and A. Boers, "MVPN: 306 Using Bidirectional P-Tunnels", 307 draft-ietf-l3vpn-mvpn-bidir-06 (work in progress), 308 October 2013. 310 Authors' Addresses 312 Jeffrey Zhang 313 Juniper Networks 314 10 Technology Park Dr. 315 Westford, MA 01886 316 US 318 Email: zzhang@juniper.net 320 Yakov Rekhter 321 Juniper Networks 322 1194 North Mathilda Ave. 323 Sunnyvale, CA 94089 324 US 326 Email: yakov@juniper.net 328 Andrew Dolganow 329 Alcatel-Lucent 330 600 March Rd. 331 Ottawa, ON K2K 2E6 332 CANADA 334 Email: andrew.dolganow@alcatel-lucent.com