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Please use uppercase 'NOT' together with RFC 2119 keywords (if that is what you mean). Found 'MUST not' in this paragraph: o The MPLS Label field in the BIER PTA of the BGP-MVPN x-PMSI A-D route MUST be ignored and MUST not be used for the identification of the VRF. -- The document date (March 11, 2019) is 1873 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) == Missing Reference: 'RFC4364' is mentioned on line 103, but not defined == Missing Reference: 'RFC8114' is mentioned on line 325, but not defined == Outdated reference: A later version (-10) exists of draft-xie-bier-ipv6-encapsulation-00 ** Obsolete normative reference: RFC 5549 (Obsoleted by RFC 8950) Summary: 1 error (**), 0 flaws (~~), 5 warnings (==), 1 comment (--). Run idnits with the --verbose option for more detailed information about the items above. -------------------------------------------------------------------------------- 2 Network Working Group J. Xie 3 Internet-Draft M. McBride 4 Intended status: Standards Track S. Dhanaraj 5 Expires: September 12, 2019 Huawei Technologies 6 L. Geng 7 China Mobile 8 March 11, 2019 10 Use of BIER IPv6 Encapsulation (BIERv6) for Multicast VPN in Non-MPLS 11 IPv6 networks 12 draft-xie-bier-ipv6-mvpn-00 14 Abstract 16 This draft defines the procedures and messages for using Bit Index 17 Explicit Replication (BIER) for Multicast VPN Services in Non-MPLS 18 IPv6 networks using the BIER IPv6 encapsulation. It provides a 19 migration path for Multicast VPN service using BIER MPLS 20 encapsulation in MPLS networks to multicast VPN service using BIER 21 IPv6 encapsulation (BIERv6) in Non-MPLS IPv6 networks. 23 Requirements Language 25 The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", 26 "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this 27 document are to be interpreted as described in [RFC2119] and 28 [RFC8174]. 30 Status of This Memo 32 This Internet-Draft is submitted in full conformance with the 33 provisions of BCP 78 and BCP 79. 35 Internet-Drafts are working documents of the Internet Engineering 36 Task Force (IETF). Note that other groups may also distribute 37 working documents as Internet-Drafts. The list of current Internet- 38 Drafts is at https://datatracker.ietf.org/drafts/current/. 40 Internet-Drafts are draft documents valid for a maximum of six months 41 and may be updated, replaced, or obsoleted by other documents at any 42 time. It is inappropriate to use Internet-Drafts as reference 43 material or to cite them other than as "work in progress." 45 This Internet-Draft will expire on September 12, 2019. 47 Copyright Notice 49 Copyright (c) 2019 IETF Trust and the persons identified as the 50 document authors. All rights reserved. 52 This document is subject to BCP 78 and the IETF Trust's Legal 53 Provisions Relating to IETF Documents 54 (https://trustee.ietf.org/license-info) in effect on the date of 55 publication of this document. Please review these documents 56 carefully, as they describe your rights and restrictions with respect 57 to this document. Code Components extracted from this document must 58 include Simplified BSD License text as described in Section 4.e of 59 the Trust Legal Provisions and are provided without warranty as 60 described in the Simplified BSD License. 62 Table of Contents 64 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 2 65 2. Terminology . . . . . . . . . . . . . . . . . . . . . . . . . 3 66 3. Use of PTA and Prefix-SID Attribute in x-PMSI A-D Routes . . 4 67 4. MVPN over BIERv6 Core . . . . . . . . . . . . . . . . . . . . 5 68 5. GTM over BIERv6 Core . . . . . . . . . . . . . . . . . . . . 7 69 6. Data Plane . . . . . . . . . . . . . . . . . . . . . . . . . 8 70 6.1. Encapsulation of Multicast Traffic . . . . . . . . . . . 8 71 6.2. MTU . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 72 6.3. TTL . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 73 7. Security Considerations . . . . . . . . . . . . . . . . . . . 9 74 8. IANA Considerations . . . . . . . . . . . . . . . . . . . . . 9 75 9. Acknowledgements . . . . . . . . . . . . . . . . . . . . . . 9 76 10. References . . . . . . . . . . . . . . . . . . . . . . . . . 9 77 10.1. Normative References . . . . . . . . . . . . . . . . . . 9 78 10.2. Informative References . . . . . . . . . . . . . . . . . 10 79 Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 11 81 1. Introduction 83 Bit Index Explicit Replication (BIER) [RFC8279] is an architecture 84 that provides optimal multicast forwarding without requiring 85 intermediate routers to maintain any per-flow state by using a 86 multicast-specific BIER header. BIERv6 refers to the deployment of 87 BIER in Non-MPLS IPv6 networks using the BIER IPv6 encapsulation 88 format defined in [I-D.xie-bier-ipv6-encapsulation]. 90 SRv6 explained in [I-D.ietf-spring-segment-routing] refers to the 91 deployment of segment routing in Non-MPLS IPv6 networks. 92 [I-D.filsfils-spring-srv6-network-programming] introduces the Network 93 programming concepts in SRv6 networks and explains how the 128-bit 94 IPv6 address can be used as SRv6 SID in the format LOC:FUNCT, where 95 LOC part of the SID is routable, while FUNCT part of the SID is an 96 opaque identification of a local function bound to the SID. It has 97 also defined some well known standard functions like End.DT4 - 98 Endpoint with decaps and IPv4 table lookup for L3VPN (equivalent to 99 per-VRF VPN label). [I-D.dawra-idr-srv6-vpn] defines the TLVs to 100 associate a function like End.DT4 with the L3VPN Unicast routes 101 advertised via BGP. It also details how the functions of End.DT4, 102 End.DT6, End.DT46 (End.DTx) can be used to identify a L3VPN/EVPN 103 instead of using a VPN Label in MPLS-VPN [RFC4364] of the received 104 data packet and thereby realize the L3VPN Services in the SRv6 105 Networks. However, it covers unicast services exclusively. 107 This document describes a method to realize MVPN services using BIER 108 as a P-tunnel in the BIERv6 Networks. It defines a method to use an 109 SRv6 Service SID like End.DTx as source address to identify the MVPN 110 instance at the Egress PE. While the End.DTx is used as IPv6 111 destination address in unicast L3VPN scenarios as defined in 112 [I-D.dawra-idr-srv6-vpn], this document extends the use of End.DTx as 113 IPv6 source address. The LOC part and FUNCT part of this SRv6 114 Service SID represent the context and the upstream-assigned VPN Label 115 respectively in MVPN scenario's as defined in [I-D.ietf-bier-mvpn]. 117 In particular, MVPN deployment in Non-MPLS IPv6 networks relies on 118 L3VPN deployment on Non-MPLS IPv6 networks firstly, thus the 119 c-multicast routing procedure like UMH Selection can be done. The 120 L3VPN deployment in Non-MPLS IPv6 networks can be referred to 121 [I-D.dawra-idr-srv6-vpn]. 123 GTM defined in [RFC7716] is also covered in this document, as GTM 124 shares the same BGP-MVPN signaling, while providing an approach of 125 Non-VPN multicast over a service provider core with various P-tunnel 126 type. For the same reason of UMH selection, and the requirement of 127 basic operation like ping (e.g, to the multicast source address), the 128 Global IPv4/IPv6 over SRv6 Core as described in 129 [I-D.dawra-idr-srv6-vpn] is also required, and the [RFC5549] may be 130 required further. 132 2. Terminology 134 Readers of this document are assumed to be familiar with the 135 terminology and concepts of the documents listed as Normative 136 References. Additionally the following terms are used through out 137 the document. 139 o BIERv6 - BIER in Non-MPLS IPv6 networks using the BIER IPv6 140 encapsulation format defined in [I-D.xie-bier-ipv6-encapsulation]. 142 o SRv6 - Segment Routing instantiated on the IPv6 dataplane as 143 defined in [I-D.filsfils-spring-srv6-network-programming]. 145 o SRv6 SID - SRv6 Segment Identifier as defined in 146 [I-D.filsfils-spring-srv6-network-programming]. 148 o End.DTx - Refers to the functions End.DT6, End.DT4, End.DT46 149 defined in [I-D.filsfils-spring-srv6-network-programming]. 151 o SRv6 L3 Service - L3VPN/Global-L3 service in Non-MPLS SRv6 network 152 defined in [I-D.dawra-idr-srv6-vpn], or MVPN/GTM service in Non- 153 MPLS BIERv6 network defined in this document. 155 3. Use of PTA and Prefix-SID Attribute in x-PMSI A-D Routes 157 The BGP-MVPN I-PMSI A-D (Type 1) or S-PMSI A-D (Type 3) route (called 158 x-PMSI A-D route in this document), advertised by Ingress PE carries 159 the BIER (Type 11) PTA as specified in [I-D.ietf-bier-mvpn]. The 160 BIER PTA carried in the x-PMSI A-D route is used for explicitly 161 tracking the receiver-site PEs which are interested in a specific 162 multicast flow. It includes three BIER-specific fields, Sub-domain- 163 id, BFR-id, and BFR-prefix. For BIER P-tunnel using the BIERv6 164 encapsulation in IPv6 networks, the BFR-prefix field in the PTA MUST 165 be set to the BFIR IPv6 prefix and the MPLS Label field in the PTA 166 MUST set to 0. For MVPN over BIERv6, the End.DTx IPv6 address of the 167 BFIR is used to identify the VRF instead of a MPLS Label. The 168 End.DTx IPv6 Address (End.DT6 or End.DT4 or End.DT46) MUST be carried 169 within an SRv6 L3 Service TLV [I-D.dawra-idr-srv6-vpn] of BGP Prefix- 170 SID attribute in the x-PMSI A-D route. 172 The Ingress PE encapsulates the c-multicast IP packet with BIERv6 173 header and the source address in the outer IPv6 header will be set to 174 the End.DTx IPv6 address advertised in the BGP-MVPN x-PMSI A-D 175 routes. See section 3 of [I-D.xie-bier-ipv6-encapsulation] for the 176 detailed packet format. 178 Egress PE (BFER) receiving the x-PMSI A-D routes with BIER PTA and 179 SRv6 L3 Service TLV learns the End.DTx IPv6 address and uses it to 180 identify the VRF of the c-multicast packet. 182 When Egress PE receives a BIERv6 packet and the self bfr-id is set in 183 the bit-string field of the Non-MPLS BIER header, it retrieves the 184 End.DTx IPv6 address from the source address of the IPv6 header to 185 determine the VRF and the Address Family (AF) of the c-multicast data 186 packet, and performs the MFIB lookup in the corresponding table. 188 4. MVPN over BIERv6 Core 190 [I-D.ietf-bier-mvpn] specifies the protocol and procedures to be 191 followed by the Ingress and Egress PEs to use BIER as a P-tunnel for 192 MVPN in MPLS networks. This section specifies the required changes 193 and procedures in addition to support BIER as a P-tunnel in Non-MPLS 194 IPv6 networks. 196 In a Non-MPLS IPv6 service provider network, many of the IP address 197 fields used in the BGP-MVPN routes are IPv6 address as specified in 198 [RFC6515]. These are listed below. 200 o "Originating Router's IP Address" in the NLRI of Type 1 or Type 3 201 BGP-MVPN route is an IPv6 address. 203 o "Network Address of Next Hop" field in the MP_REACH_NLRI attribute 204 is an IPv6 address. 206 o Route Targets Extended Community (EC) used in C-multicast join 207 (Type 6 or 7) route or Leaf A-D (Type 5) route is an IPv6 Address 208 Specific Extended Community, where the Global Administrator field 209 will be an IPv6 address identifies the Upstream PE or the UMH. 211 o "VRF Route Import Extended Community (EC)" carried by unicast VPN- 212 IPv4 or VPN-IPv6 routes as [RFC6515] specifies, or SAFI 1, 2, or 4 213 unicast routes, or MVPN (SAFI 5) Source-Active routes as [RFC7716] 214 specifies. 216 On the Ingress PE (BFIR), the BGP-MVPN x-PMSI A-D route is 217 constructed as per the procedures specified in [I-D.ietf-bier-mvpn] 218 and with the following specifications. 220 o MPLS Label field in the BIER PTA MUST be set to Zero. 222 o BFR-prefix field in the BIER PTA MUST be set to the Ingress PEs 223 (BFIR) IPv6 BFR-Prefix Address. It does not need to be the same 224 as the other IPv6 address of the x-PMSI AD route. 226 o Route MUST also carry an BGP Prefix SID attribute with an SRv6 L3 227 Service TLV carrying an End.DTx IPv6 address uniquely identifying 228 the MVPN instance. 230 If the VPN is IPv4 VPN, the End.DTx can be either End.DT4 or 231 End.DT46. If the VPN is IPv6 VPN, the End.DTx can be either End.DT6 232 or End.DT46. By default, the distribution of the x-PMSI A-D routes 233 uses the same End.DTx as the ones used for the distribution of VPN-IP 234 unicast routes. That is, by default, the x-PMSI A-D route MUST carry 235 the same SRv6-Service-SID used by the unicast routing for L3VPN. The 236 default could be modified via configuration by having a End.DTx used 237 for the BGP-MVPN x-PMSI A-D routes being distinct from the ones used 238 for the VPN-IP unicast routes. 240 BFIR MAY carry the BGP Prefix-SID attribute only in I-PMSI A-D route 241 when I-PMSI A-D route is used, while other S-PMSI A-D routes do not 242 carry the BGP Prefix-SID attribute. 244 BFIR MAY carry the BGP Prefix-SID attribute only in wildcard S-PMSI 245 A-D routes when the "S-PMSI Only" mode as described in [RFC6625] is 246 used, while other S-PMSI A-D routes do not carry the BGP Prefix-SID 247 attribute. 249 On the Egress PE (BFER), the BGP-MVPN x-PMSI A-D route is processed 250 as per the procedures specified in [I-D.ietf-bier-mvpn] and with the 251 following specifications: 253 o The MPLS Label field in the BIER PTA of the BGP-MVPN x-PMSI A-D 254 route MUST be ignored and MUST not be used for the identification 255 of the VRF. 257 o The BGP-MVPN x-PMSI A-D route MUST be dropped if the BFR-prefix 258 field in the BIER PTA is not an IPv6 address. 260 o The BGP-MVPN x-PMSI A-D route MUST be dropped if it does not carry 261 a End.DTx IPv6 address in the SRv6 L3 Service TLV in BGP Prefix 262 SID attribute. 264 o Leaf A-D route originated by the Egress PE (BFER) MUST carry the 265 BIER PTA with the BFR-prefix field set to the BFER IPv6 BFR- 266 prefix. 268 Valid BGP-MVPN x-PMSI A-D route received by an Egress PE (BFER) is 269 stored locally, and the End.DTx IPv6 Address carried in the SRv6 L3 270 service TLV is used to identify the VRF of a c-multicast data packet. 271 This may be populated into forwarding table only when there is 272 c-multicast flow state with UMH of the specific BFIR this End.DTx 273 located in. 275 If more than one x-PMSI A-D routes belonging to the same VRF has 276 different End.DTx value, the processing is determined by the local 277 policy of the BFER. 279 If more than one x-PMSI A-D routes belonging to different VRF has the 280 same End.DTx value, the BFER must log an error, and a BIERv6 packet 281 with this End.DTx as the IPv6 source address MUST be dropped. 283 The BGP Prefix-SID attribute (which may include the End.DTx in SRv6 284 L3 Service TLV) MUST NOT be carried in Leaf A-D route upon sending, 285 and MUST be ignored upon reception. 287 5. GTM over BIERv6 Core 289 As specified in [RFC7716], Global Table Multicast (GTM) uses the same 290 Subsequent Address Family Identifier (SAFI) value, the same Network 291 Layer Reachability Information (NLRI) format, and the same procedures 292 of MVPN with only a few adaptions. It support for both IPv4 and IPv6 293 multicast flows over either an IPv4 or IPv6 SP infrastructure. GTM 294 over BIERv6 core is obviously a case of IPv4/IPv6 multicast over an 295 IPv6 SP infrastructure with BIERv6 data-plane. 297 The BIER (Type 11) PTA attribute and the BGP Prefix-SID attribute are 298 carried in the x-PMSI A-D route in GTM cases. When the a BGP-MVPN 299 x-PMSI A-D route is received by Egress PE, it is stored locally, and 300 the End.DTx IPv6 Address of the Ingress PE in the route is used to 301 determine the VRF of a packet, which is the 'public' VRF in the case 302 of GTM. 304 There are some other attributes listed below for GTM over a BIERv6 305 core: 307 o Route Distinguishers - the RD field of a BGP-MVPN route's NLRI 308 MUST be set to zero (i.e., to 64 bits of zero) to represent a Non- 309 VPN GTM. See section 2.2 of [RFC7716]. 311 o Route Targets Extended Community (EC) - The RT EC carried by the 312 BGP-MVPN C-multicast (Type 6 or 7) route or Leaf A-D (Type 4) 313 route MUST be an IPv6-address-specific Extended Community (EC). 314 The Global Administrator field identifies the Upstream PE or the 315 UMH, and the Local Administrator field MUST always be set to zero 316 in GTM case. 318 o VRF Route Import Extended Community (EC) - The VRF Route Import EC 319 used in BIERv6 core MUST be an IPv6-address-specific EC if used, 320 either used in UMH-eligible unicast routes having a SAFI of 1, 2, 321 or 4, or used in the MVPN (SAFI of 5) Source Active A-D route. 323 GTM IPv4 multicast over an BIERv6 core may be considered an 324 alternative to support IPv4 IPTV content delivery during transition 325 to IPv6 period comparing to [RFC8114]. They both use IPv4-in-IPv6 326 encapsulation, while BIERv6 uses an additional BIER header within an 327 IPv6 Extension header to support stateless core. 329 6. Data Plane 331 6.1. Encapsulation of Multicast Traffic 333 BIER IPv6 encapsulation (BIERv6) [I-D.xie-bier-ipv6-encapsulation] is 334 used for forwarding the c-multicast traffic through an IPv6 core. 335 The following diagram shows the progression of an MVPN c-multicast 336 packet as it enters and leaves the intra-AS service-provider network. 338 +---------------+ +---------------+ 339 | P-IPv6 Header | | P-IPv6 Header | 340 | ( SA=End.DTx | | ( SA=End.DTx | 341 | DA=mcBIER ) | | DA=mcBIER ) | 342 +---------------+ +---------------+ 343 | P-IPv6 ExtHdr | | P-IPv6 ExtHdr | 344 | (BIER header) | | (BIER header) | 345 ++=========++ ++=============++ ++=============++ ++=========++ 346 ||C-IP Hdr || || C-IP Hdr || || C-IP Hdr || ||C-IP Hdr || 347 ++=========++ >> ++=============++ >> ++=============++ >> ++=========++ 348 ||C-Payload|| || C-Payload || || C-Payload || ||C-Payload|| 349 ++=========++ ++=============++ ++=============++ ++=========++ 350 CE1-----------PE1------------------P2------------------PE2-----------CE2 352 Figure 1: BIERv6 MVPN/GTM Intra-AS 354 In case of inter-AS scenario, BIERv6 packets may travel through 355 unicast to a Boarder Router (BR), and then replicate in a single 356 intra-AS BIERv6 domain. How such non-segmented BIERv6 scenario can 357 be supported is outside the scope of this document. 359 How segmented MVPN, for example, between BIERv6 and BIERv6, or 360 between BIERv6 and Ingress Replication(IR) in Non-MPLS IPv6 networks, 361 is outside the scope of this document. 363 6.2. MTU 365 Each BFIR is expected to know the Maximum Transmission Unit (MTU) of 366 the BIER domain. This may be known by provisioning, or by method 367 specified in [draft-ietf-bier-mtud]. The section 3 of [RFC8296] 368 applies. 370 6.3. TTL 372 The ingress PE (BFIR) should not copy the Time to Live (TTL) field 373 from the payload IP header received from a CE router to the delivery 374 IP header. Setting the TTL of the delivery IP header is determined 375 by the local policy of the ingress PE (BFIR) router per section 3 of 376 [RFC8296]. 378 7. Security Considerations 380 The procedures of this document do not, in themselves, provide 381 privacy, integrity, or authentication for the control plane or the 382 data plane. 384 8. IANA Considerations 386 No IANA allocation is required. 388 9. Acknowledgements 390 TBD. 392 10. References 394 10.1. Normative References 396 [I-D.dawra-idr-srv6-vpn] 397 Dawra, G., Filsfils, C., Dukes, D., Brissette, P., 398 Camarillo, P., Leddy, J., daniel.voyer@bell.ca, d., 399 daniel.bernier@bell.ca, d., Steinberg, D., Raszuk, R., 400 Decraene, B., Matsushima, S., and S. Zhuang, "BGP 401 Signaling for SRv6 based Services.", draft-dawra-idr- 402 srv6-vpn-05 (work in progress), October 2018. 404 [I-D.filsfils-spring-srv6-network-programming] 405 Filsfils, C., Camarillo, P., Leddy, J., 406 daniel.voyer@bell.ca, d., Matsushima, S., and Z. Li, "SRv6 407 Network Programming", draft-filsfils-spring-srv6-network- 408 programming-07 (work in progress), February 2019. 410 [I-D.ietf-bier-mvpn] 411 Rosen, E., Sivakumar, M., Aldrin, S., Dolganow, A., and T. 412 Przygienda, "Multicast VPN Using BIER", draft-ietf-bier- 413 mvpn-11 (work in progress), March 2018. 415 [I-D.ietf-spring-segment-routing] 416 Filsfils, C., Previdi, S., Ginsberg, L., Decraene, B., 417 Litkowski, S., and R. Shakir, "Segment Routing 418 Architecture", draft-ietf-spring-segment-routing-15 (work 419 in progress), January 2018. 421 [I-D.xie-bier-ipv6-encapsulation] 422 Xie, J., Geng, L., McBride, M., Dhanaraj, S., Yan, G., and 423 Y. Xia, "Encapsulation for BIER in Non-MPLS IPv6 424 Networks", draft-xie-bier-ipv6-encapsulation-00 (work in 425 progress), March 2019. 427 [RFC5549] Le Faucheur, F. and E. Rosen, "Advertising IPv4 Network 428 Layer Reachability Information with an IPv6 Next Hop", 429 RFC 5549, DOI 10.17487/RFC5549, May 2009, 430 . 432 [RFC6515] Aggarwal, R. and E. Rosen, "IPv4 and IPv6 Infrastructure 433 Addresses in BGP Updates for Multicast VPN", RFC 6515, 434 DOI 10.17487/RFC6515, February 2012, 435 . 437 [RFC6625] Rosen, E., Ed., Rekhter, Y., Ed., Hendrickx, W., and R. 438 Qiu, "Wildcards in Multicast VPN Auto-Discovery Routes", 439 RFC 6625, DOI 10.17487/RFC6625, May 2012, 440 . 442 [RFC7716] Zhang, J., Giuliano, L., Rosen, E., Ed., Subramanian, K., 443 and D. Pacella, "Global Table Multicast with BGP Multicast 444 VPN (BGP-MVPN) Procedures", RFC 7716, 445 DOI 10.17487/RFC7716, December 2015, 446 . 448 [RFC8279] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A., 449 Przygienda, T., and S. Aldrin, "Multicast Using Bit Index 450 Explicit Replication (BIER)", RFC 8279, 451 DOI 10.17487/RFC8279, November 2017, 452 . 454 [RFC8296] Wijnands, IJ., Ed., Rosen, E., Ed., Dolganow, A., 455 Tantsura, J., Aldrin, S., and I. Meilik, "Encapsulation 456 for Bit Index Explicit Replication (BIER) in MPLS and Non- 457 MPLS Networks", RFC 8296, DOI 10.17487/RFC8296, January 458 2018, . 460 10.2. Informative References 462 [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate 463 Requirement Levels", BCP 14, RFC 2119, 464 DOI 10.17487/RFC2119, March 1997, 465 . 467 [RFC8174] Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC 468 2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174, 469 May 2017, . 471 Authors' Addresses 473 Jingrong Xie 474 Huawei Technologies 476 Email: xiejingrong@huawei.com 478 Mike McBride 479 Huawei Technologies 481 Email: michael.mcbride@huawei.com 483 Senthil Dhanaraj 484 Huawei Technologies 486 Email: senthil.dhanaraj@huawei.com 488 Liang Geng 489 China Mobile 491 Email: gengliang@chinamobile.com