From 4bfd864f10b68b71482b35c818559068ef8d5797 Mon Sep 17 00:00:00 2001 From: Thomas Voss Date: Wed, 27 Nov 2024 20:54:24 +0100 Subject: doc: Add RFC documents --- doc/rfc/rfc7625.txt | 843 ++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 843 insertions(+) create mode 100644 doc/rfc/rfc7625.txt (limited to 'doc/rfc/rfc7625.txt') diff --git a/doc/rfc/rfc7625.txt b/doc/rfc/rfc7625.txt new file mode 100644 index 0000000..23a2562 --- /dev/null +++ b/doc/rfc/rfc7625.txt @@ -0,0 +1,843 @@ + + + + + + +Independent Submission J. T. Hao +Request for Comments: 7625 Huawei Technologies Co., Ltd +Category: Informational P. Maheshwari +ISSN: 2070-1721 Bharti Airtel, Ltd. + R. Huang + L. Andersson + M. Chen + Huawei Technologies Co., Ltd + August 2015 + + + Architecture of an IP/MPLS Network with Hardened Pipes + +Abstract + + This document describes an IP/MPLS network that has an infrastructure + that can be separated into two or more strata. For the + implementation described in this document, the infrastructure has + been separated into two strata: one for the "Hard Pipes", called the + "Hard Pipe Stratum", and one for the normal IP/MPLS traffic, called + the "Normal IP/MPLS Stratum". + + This document introduces the concept of a Hard Pipe -- an MPLS Label + Switched Path (LSP) or a pseudowire (PW) with a bandwidth that is + guaranteed and can neither be exceeded nor infringed upon. + + The Hard Pipe stratum does not use statistical multiplexing; for the + LSPs and PWs set up within this stratum, the bandwidth is guaranteed + end to end. + + The document does not specify any new protocol or procedures. It + does explain how the MPLS standards implementation has been deployed + and operated to meet the requirements from operators that offer + traditional Virtual Leased Line (VLL) services. + + + + + + + + + + + + + + + + + +Hao, et al. Informational [Page 1] + +RFC 7625 Hard IP Pipes August 2015 + + +Status of This Memo + + This document is not an Internet Standards Track specification; it is + published for informational purposes. + + This is a contribution to the RFC Series, independently of any other + RFC stream. The RFC Editor has chosen to publish this document at + its discretion and makes no statement about its value for + implementation or deployment. Documents approved for publication by + the RFC Editor are not a candidate for any level of Internet + Standard; see Section 2 of RFC 5741. + + Information about the current status of this document, any errata, + and how to provide feedback on it may be obtained at + http://www.rfc-editor.org/info/rfc7625. + +Copyright Notice + + Copyright (c) 2015 IETF Trust and the persons identified as the + document authors. All rights reserved. + + This document is subject to BCP 78 and the IETF Trust's Legal + Provisions Relating to IETF Documents + (http://trustee.ietf.org/license-info) in effect on the date of + publication of this document. Please review these documents + carefully, as they describe your rights and restrictions with respect + to this document. + + + + + + + + + + + + + + + + + + + + + + + + +Hao, et al. Informational [Page 2] + +RFC 7625 Hard IP Pipes August 2015 + + +Table of Contents + + 1. Introduction . . . . . . . . . . . . . . . . . . . . . . . . 3 + 1.1. Scope . . . . . . . . . . . . . . . . . . . . . . . . . . 4 + 1.2. Abbreviations . . . . . . . . . . . . . . . . . . . . . . 4 + 2. The Stratified Network . . . . . . . . . . . . . . . . . . . 5 + 2.1. The Physical Network . . . . . . . . . . . . . . . . . . 6 + 2.2. The Hard Pipe Stratum . . . . . . . . . . . . . . . . . . 6 + 2.3. The Normal IP/MPLS Stratum . . . . . . . . . . . . . . . 7 + 2.4. Stratum Networks . . . . . . . . . . . . . . . . . . . . 7 + 3. Configuring the Leased Lines in the Hard Pipe Stratum . . . . 8 + 4. Efficient State Management . . . . . . . . . . . . . . . . . 9 + 4.1. State in the Forwarding Plane . . . . . . . . . . . . . . 9 + 4.2. State in the NMS/Controller . . . . . . . . . . . . . . . 10 + 4.3. Annotations for Configuring Leased Lines . . . . . . . . 10 + 5. Setting Up Leased Lines . . . . . . . . . . . . . . . . . . . 12 + 6. Leased Line Protection . . . . . . . . . . . . . . . . . . . 13 + 7. Security Considerations . . . . . . . . . . . . . . . . . . . 13 + 8. Informative References . . . . . . . . . . . . . . . . . . . 13 + Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . . 14 + Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . 15 + +1. Introduction + + IP leased line services, Ethernet Private Line (EPL), and Time- + Division Multiplexed (TDM) leased line services are commonly offered + by operators worldwide. + + There are customers, e.g., many enterprises, that insist on TDM + leased line services. They do so regardless of the fact that the + same operators often offer IP leased line services and EPL services + at a lower price and with a guaranteed bandwidth. + + Today we see a trend that TDM (in particular, Synchronous Digital + Hierarchy / Synchronous Optical Network (SDH/SONET)) networks are + gradually carrying less and less traffic, and many operators want to + shut their TDM networks down to reduce costs. + + In light of these trends, vendors and operators have built and + deployed the Hard Pipe service described in this document. It is a + way to introduce leased line service with the same characteristics as + TDM leased line services in IP/MPLS networks. + + Even if leased line has been the initial motivation to define the + Hard Pipe technology, the Hard Pipe is by no means limited to support + leased line services. When guaranteed bandwidth is the priority, + + + + + +Hao, et al. Informational [Page 3] + +RFC 7625 Hard IP Pipes August 2015 + + + Virtual Private Wire Services (VPWS), Virtual Private LAN Services + (VPLS), L3 Virtual Private Networks (L3VPN), and IP-only Private LAN + Services can be mapped to a tunnel in the Hard Pipe stratum. + + EPL and Ethernet Private LAN (EPLAN) are out of scope for this + document. + + Virtual Leased Line service is used in examples throughout this + document. + + The solution soon to be deployed has an Ethernet infrastructure that + has been split into two parallel logical networks -- two parallel + strata. The first stratum -- the Hard Pipe Stratum -- does not use + statistical multiplexing, and bandwidth is guaranteed end to end. + The second stratum -- the Normal IP/MPLS Stratum -- works as a normal + IP/MPLS network. The two strata share the same physical network, + i.e., routers and links, but the resource reserved for the Hard Pipe + stratum will never be preempted by the Normal IP/MPLS stratum. + + The routers will handle the traffic belonging to one stratum + differently from how traffic from the other stratum is handled. This + separation in traffic handling is based on support in hardware. + + The reader of this document is assumed to be familiar with RFC 3031 + [RFC3031] and RFC 5921 [RFC5921]. + +1.1. Scope + + This document has the following purposes: + + o to introduce a two strata IP/MPLS network: the purpose of one of + the strata is to provide capabilities for services that are, from + a customer's point of view, functionally identical to TDM-like + leased lines; and + + o to indicate how a router differentiates the traffic of the two + strata. + +1.2. Abbreviations + + CC: Continuity Check + + CV: Connection Verification + + L-label: Leased Line label + + LSP: Label Switched Path + + + + +Hao, et al. Informational [Page 4] + +RFC 7625 Hard IP Pipes August 2015 + + + LSR: Label Switching Router + + MPLS-TP: MPLS Transport Profile + + NMS: Network Management System + + OAM: Operations, Administration, and Maintenance + + P: Provider Router + + PE: Provider Edge Router + + PW: Pseudowire + + T-label: Tunnel label + + TDM: Time-Division Multiplexing + + tLDP: Targeted LDP + + VLL: Virtual Leased Line + + VPLS: Virtual Private LAN Service + + VPWS: Virtual Private Wire Service + +2. The Stratified Network + + The concept of stratified or strata networks has been around for some + time. It appears to have different meaning in different contexts. + The way we use the concept is that we logically assign certain + characteristics to part of the network. The part of the network that + has the special characteristics form one stratum, and the "remainder" + forms a second stratum. The network described in this document uses + a single link-layer technology, Ethernet. + + In many cases, a whole physical interface is assigned to a single + hard stratum, especially in the scenario where there are many + physical links between two nodes. + + This document does not address the network configuration + possibilities for Hard Pipe and IP/MPLS strata in detail. There are + configuration options, the basic configuration is that one Hard Pipe + stratum and one IP/MPLS stratum are provisioned. + + + + + + + +Hao, et al. Informational [Page 5] + +RFC 7625 Hard IP Pipes August 2015 + + + However, it is also possible to provision more than one Hard Pipe + stratum, e.g., if customers want enhanced separation for their leased + line. Even though the main driver for the Hard Pipe technology is + the leased lines, any service for which an operator does not want to + use statistical multiplexing will benefit from using the Hard Pipes. + +2.1. The Physical Network + + Consider a network with 10 routers and all the links between are 10G + Ethernet, such as shown in Figure 1. This is the network topology + we've used for this model and also (with topology variations) in our + first deployment. + + +---+ 10G +---+ 10G +---+ 10G +---+ + +---| B |-----------| C |-----------| D |----------| E |---+ + 10G | +---+ +---+ +---+ +---+ | 10G + | | | | | | + +---+ | 10G 10G | 10G | 10G | +---+ + --| F | | | | | | G |-- + +---+ | | | | +---+ + | | | | | | + 10G | +---+ +---+ +---+ +---+ | 10G + +---| H |-----------| J |-----------| K |----------| L |---+ + +---+ 10G +---+ 10G +---+ 10G +---+ + + Figure 1 + + In this document, we use the terms "traffic matrix" or "estimated + traffic matrix" to indicate an estimate of how much traffic will flow + between the ingress and egress (PE) nodes. This may be translated + into how much bandwidth is needed per link in the Hard Pipe stratum. + +2.2. The Hard Pipe Stratum + + When the intention is to define a Hard Pipe stratum, it is, for + example, possible to start from an estimated traffic matrix to + estimate how much bandwidth to reserve on the links of the Ethernet + link-layer network for the Hard Pipes. + + Note that the implication is that the normal traffic gets the + remainder of the available bandwidth. Thus, the link-layer network + will be split into two logical networks, or two strata -- one stratum + for the hardened pipe network and the other for the "normal" IP and + MPLS traffic. This is shown in Figures 2 and 3. + + + + + + + +Hao, et al. Informational [Page 6] + +RFC 7625 Hard IP Pipes August 2015 + + + +---+ 2G +---+ +---+ + +---| B |-----------| C | | E |---+ + 1G | +---+ +---+ +---+ | 2G + | | | | + +---+ 2G | 1G | +---+ + --| F | | | | G |-- + +---+ | | +---+ + | | | | + 1G | +---+ +---+ +---+ +---+ | 2G + +---| H |-----------| J |-----------| K |----------| L |---+ + +---+ 2G +---+ 4G +---+ 4G +---+ + + Figure 2: The Hard Pipe Stratum + + It is worth noting that even if the figures in this document are + drawn to indicate "bandwidth on the link", the only bandwidth + information that the nodes have available is the bandwidth assigned + to the Hard Pipe stratum and the Normal IP/MPLS stratum. All other + information is kept on the NMS/Controller. The NMS/Controller keeps + a global bandwidth resource table for the Hard Pipe stratum. + +2.3. The Normal IP/MPLS Stratum + + Given that the starting point is the physical network in Figure 1 and + the Hard Pipe stratum as defined in Figure 2, the Normal IP/MPLS + stratum will look as is shown in Figure 3: + + +---+ 8G +---+ 10G +---+ 10G +---+ + +---| B |-----------| C |-----------| D |----------| E |---+ + 9G | +---+ +---+ +---+ +---+ | 8G + | | | | | | + +---+ | 10G 8G | 10G | 9G | +---+ + --| F | | | | | | G |-- + +---+ | | | | +---+ + | | | | | | + 9G | +---+ +---+ +---+ +---+ | 9G + +---| H |-----------| J |-----------| K |----------| L |---+ + +---+ 8G +---+ 6G +---+ 6G +---+ + + Figure 3: The Normal IP/MPLS Stratum + +2.4. Stratum Networks + + In this document, the concept of stratum network is used to indicate + basically parallel logical networks with strictly separated + resources. Traffic sent over one stratum network can not infringe on + traffic in the other stratum network. + + + + +Hao, et al. Informational [Page 7] + +RFC 7625 Hard IP Pipes August 2015 + + + In the case described here, all the traffic in the Hard Pipe stratum + is MPLS encapsulated. A number of the labels have been set aside so + other applications can't allocate them and so the routers recognize + them as belonging to the Hard Pipe application. + +3. Configuring the Leased Lines in the Hard Pipe Stratum + + When the strata are provisioned, the IP/MPLS stratum is set up + exactly as any other IP/MPLS network. The one small difference + between provisioning the Hard Pipe stratum and the IP/MPLS stratum is + that no overbooking is done for the Hard Pipe stratum. + + Overbooking and/or congestion in the IP/MPLS stratum can not affect + the Hard Pipe stratum. + + All labels used for the Hard Pipe stratum are "Configured Labels", + i.e., labels that are provisioned and reclaimed by management + actions. These management actions can be by manual actions or by an + NMS/Controller or a centralized controller. For the size of network + being deployed, manual configuration is not practical; we are both + provisioning and reclaiming a label from an NMS/Controller. + + o If an operator wants to set up a leased line, it is first checked + if there is a path available in the Hard Pipe stratum that matches + the criteria (e.g., bandwidth) for the requested leased line. + + * If such a path does exist, it is checked if there is a matching + MPLS tunnel available over that path. + + + If such a tunnel exists, it is used to establish the leased + line by adding L-labels forming an LSP that are carried by + the tunnel. L-labels are known only by the ingress and + egress LSRs. They are local to the endpoints the same way + that the label signaled by Targeted LDP (tLDP) is local to + the endpoints of a targeted session LSP. (Here, "Targeted + LDP" means LDP as defined in RFC 5036 [RFC5036], using + Targeted Hello messages.) + + At the same time, the available bandwidth in the Hard Pipe + stratum is decremented by the bandwidth that is needed for + the leased line for every hop across this stratum in the + global resource table (for the Hard Pipe stratum). + + + If such a tunnel does not exist, it can be established so + that the leased line can be set up as above. + + + + + + +Hao, et al. Informational [Page 8] + +RFC 7625 Hard IP Pipes August 2015 + + + * If the path does not exist (not enough bandwidth in the Hard + Pipe stratum for the leased line), available bandwidth on the + links is checked to see if the stratum can be expanded to + accommodate such a path. + + + If the Hard Pipe stratum can be expanded, this is done and + the tunnel for the leased line is established as described + above. + + It is likely that other modifications of the Hard Pipe + stratum, e.g., consolidating already set up Hard IP tunnels + on to existing links so that room for new leased lines are + created, may have implications that go well outside the + leased line service, and it is currently not viewed as a + fully automated operation. + + + If it is not possible to expand the Hard Pipe stratum to + accommodate the new path, set up of the leased line will + need to be declined. + + Thus, given the existence of a viable Hard Pipe stratum, leased lines + are configured in two very simple steps. First, establish a hop-by- + hop tunnel (T-labels), and second, configure the leased lines + (L-labels). The T-labels need to be configured on both the PE and P + routers while L-labels only need to be configured on the PE routers. + + Note that L-labels may be used for normal IP service [RFC3031], + BGP/MPLS VPNs [RFC4364], or PWs [RFC3985]. + +4. Efficient State Management + + The system as described here generates a very small amount of state, + and most of it is kept in the NMS/Controller. + +4.1. State in the Forwarding Plane + + The only configured information that is actually kept on the LSRs is + + o the information needed for the label swapping procedures, i.e., + incoming label to outgoing label and port, and whether the label + belongs to the set of labels that are set aside for the Hard Pipe + stratum tunnels; and + + o the bandwidth available for the Hard Pipe stratum and the Normal + IP/MPLS stratum. + + + + + + +Hao, et al. Informational [Page 9] + +RFC 7625 Hard IP Pipes August 2015 + + +4.2. State in the NMS/Controller + + The following state needs to be kept in the NMS/Controller: + + o the topology and bandwidth resources available in the Hard Pipe + network; see Figure 2. + + o the total and available bandwidth per link in the Hard Pipe + network; see Figure 4. + + o the T-label mappings; see Figure 5. + + o the L-label mappings; see Figure 6. + + o the reserved bandwidth, as well as other constraints and the path + per L-label. + +4.3. Annotations for Configuring Leased Lines + + The annotations given below are neither a programming guideline nor + an indication how this architecture could be implemented. It is + rather an indication of how much data needs to be saved for each + stratum and leased line, as well as where this data could be stored. + + Considering the Hard Pipe stratum as it has been outlined in + Figure 2, there is actually some additional information related to + the Hard Pipe stratum that not is shown in the figure. + + Looking explicitly on the link between LSR J and K we find: + + +---+ +---+ +---+ +---+ + ---| H |-----------| J |-----------| K |----------| L |--- + +---+ +---+ +---+ +---+ + [4,0]G + + Figure 4 + + The annotation [4,0]G means that 4G is allocated to the stratum on + the link between J and K, and of these, 0G has been allocated to a + service. + + + + + + + + + + + +Hao, et al. Informational [Page 10] + +RFC 7625 Hard IP Pipes August 2015 + + + If we were to allocate two tunnels labels from the labels that have + been configured to work within the Hard Pipe stratum, the resource + view would look like this: + + +---+ +---+ +---+ +---+ + ---| H |-----------| J |-----------| K |----------| L |--- + +---+ +---+ +---+ +---+ + [4,0]G T1 ,T2 + + Figure 5 + + Note that allocating the tunnel labels does not reserve bandwidth for + the tunnel from the Hard Pipe stratum. + + When the L-labels are assigned, this will consume bandwidth; so we + need to keep track of the bandwidth per leased line and the total of + bandwidth allocated from the Hard Pipe stratum. + + The annotation for the link between J and K could look like this: + + +---+ +---+ +---+ +---+ + ---| H |-----------| J |-----------| K |----------| L |--- + +---+ +---+ +---+ +---+ + [4,1.5]G, T1, L1 [.5], L2 [.5], T2, L1 [.5] + + Figure 6 + + The line [4,1.5]G, T1, L1 [.5], L2 [.5], T2, L1 [.5] would be + interpreted as follows: + + The Hard Pipe stratum link between nodes J and K has 4G bandwidth + allocated; of the total bandwidth, 1.5G is allocated for leased + lines. + + Tunnel label T1 carries two leased lines, each of 0.5G, and tunnel + label T2 carries a third leased line of 0.5G. + + Note that it is not necessary to keep this information in the nodes; + it is held within the NMS/Controller. Also, it is not necessary to + keep the bandwidth per leased line, but some operations are + simplified (e.g., removing a leased line) if this is done. + + + + + + + + + + +Hao, et al. Informational [Page 11] + +RFC 7625 Hard IP Pipes August 2015 + + +5. Setting Up Leased Lines + + Consider the case where an operator wants to set up a leased line of + 0.4G from F to G in the Hard Pipe stratum in Figure 2. + + Since there are no constraints other than bandwidth and ingress and + egress PEs, the shortest path will be chosen. A tunnel will be + configured from F to G over the nodes F, H, J, K, L, and G, and a + Leased Line label (a) will be configured on F and G, and the + available resources will be recalculated. + + A second leased line of 0.3G between the same PEs is easily + configured by adding a new Leased Line label (b) at the ingress and + egress PEs. + + After these operations, a view of the Hard Pipe stratum resources + (available bandwidth) would look like this: + + +---+ 2G +---+ +---+ + +---| B |-----------| C | | E |---+ + 1G | +---+ +---+ +---+ | 2G + | | | | + +---+ 2G | 1G | +---+ + --| F | | | | G |-- + +---+ | | +---+ + | | | | + .3G | +---+ +---+ +---+ +---+ | 1.3G + +---| H |-----------| J |-----------| K |----------| L |---+ + +---+ 1.3G +---+ 3.3G +---+ 3.3G +---+ + + Figure 7: The Hard Pipe Stratum after Operations + + If the operator now wishes to establish a new leased line with the + criteria being that it should originate from F and terminate at G, + have 0.4G bandwidth, and pass through node E, then analysis of the + Hard Pipe stratum (after establishing the first two listed lines) and + the criteria for the new leased line would give the following: + + o The existing tunnel cannot be used since it does not pass through + E; a new tunnel need to be established. + + o The hop from F to H cannot be used since the available bandwidth + is insufficient. + + o Since no existing tunnels meet the criteria requested, a new + tunnel will be set up from F, to B, C, J, K, L, E (the criteria to + pass through E), and to G. + + + + +Hao, et al. Informational [Page 12] + +RFC 7625 Hard IP Pipes August 2015 + + + A new L-label (c) to be carried over T2 will be configured on F and + G, and the available resources of the Hard Pipe stratum will be + recalculated. + +6. Leased Line Protection + + This leased line service uses the MPLS Transport Profile (MPLS-TP) + line protection as it is defined in RFC 6378 [RFC6378] and is updated + as specified in RFC 7271 [RFC7271] and RFC 7324 [RFC7324] + + The CV and CC are run over the tunnels between the Maintenance Entity + Group End Points (MEP) at each end, i.e., the entire tunnel is + protected end to end. + + In general, all of the MPLS-TP Operations, Administration, and + Maintenance (OAM) as defined in RFC 6371 [RFC6371] is v applicable. + +7. Security Considerations + + The security considerations as defined in "Security Framework for + MPLS and GMPLS Networks" (RFC 5920 [RFC5920]) and "MPLS Transport + Profile (MPLS-TP) Security Framework" (RFC 6941 [RFC6941]) apply to + this document. + +8. Informative References + + [RFC3031] Rosen, E., Viswanathan, A., and R. Callon, "Multiprotocol + Label Switching Architecture", RFC 3031, + DOI 10.17487/RFC3031, January 2001, + . + + [RFC3985] Bryant, S., Ed. and P. Pate, Ed., "Pseudo Wire Emulation + Edge-to-Edge (PWE3) Architecture", RFC 3985, + DOI 10.17487/RFC3985, March 2005, + . + + [RFC4364] Rosen, E. and Y. Rekhter, "BGP/MPLS IP Virtual Private + Networks (VPNs)", RFC 4364, DOI 10.17487/RFC4364, February + 2006, . + + [RFC5036] Andersson, L., Ed., Minei, I., Ed., and B. Thomas, Ed., + "LDP Specification", RFC 5036, DOI 10.17487/RFC5036, + October 2007, . + + [RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS + Networks", RFC 5920, DOI 10.17487/RFC5920, July 2010, + . + + + + +Hao, et al. Informational [Page 13] + +RFC 7625 Hard IP Pipes August 2015 + + + [RFC5921] Bocci, M., Ed., Bryant, S., Ed., Frost, D., Ed., Levrau, + L., and L. Berger, "A Framework for MPLS in Transport + Networks", RFC 5921, DOI 10.17487/RFC5921, July 2010, + . + + [RFC6371] Busi, I., Ed. and D. Allan, Ed., "Operations, + Administration, and Maintenance Framework for MPLS-Based + Transport Networks", RFC 6371, DOI 10.17487/RFC6371, + September 2011, . + + [RFC6378] Weingarten, Y., Ed., Bryant, S., Osborne, E., Sprecher, + N., and A. Fulignoli, Ed., "MPLS Transport Profile + (MPLS-TP) Linear Protection", RFC 6378, + DOI 10.17487/RFC6378, October 2011, + . + + [RFC6941] Fang, L., Ed., Niven-Jenkins, B., Ed., Mansfield, S., Ed., + and R. Graveman, Ed., "MPLS Transport Profile (MPLS-TP) + Security Framework", RFC 6941, DOI 10.17487/RFC6941, April + 2013, . + + [RFC7271] Ryoo, J., Ed., Gray, E., Ed., van Helvoort, H., + D'Alessandro, A., Cheung, T., and E. Osborne, "MPLS + Transport Profile (MPLS-TP) Linear Protection to Match the + Operational Expectations of Synchronous Digital Hierarchy, + Optical Transport Network, and Ethernet Transport Network + Operators", RFC 7271, DOI 10.17487/RFC7271, June 2014, + . + + [RFC7324] Osborne, E., "Updates to MPLS Transport Profile Linear + Protection", RFC 7324, DOI 10.17487/RFC7324, July 2014, + . + +Acknowledgements + + The authors want to thank Andy Malis for detailed technical and + language review and for valuable comments. + + + + + + + + + + + + + + +Hao, et al. Informational [Page 14] + +RFC 7625 Hard IP Pipes August 2015 + + +Authors' Addresses + + JiangTao Hao + Huawei Technologies Co., Ltd + Q13 Huawei Campus + No. 156 Beiqing Road + Hai-dian District + Beijing 100095 + China + Email: haojiangtao@huawei.com + + + Praveen Maheshwari + Bharti Airtel, Ltd. + Plot No. 16, Udyog Bihar, + Phase IV, Gurgaon - 122015 + Haryana + India + Email: Praveen.Maheshwari@in.airtel.com + + + River Huang + Huawei Technologies Co., Ltd + Q13 Huawei Campus + No. 156 Beiqing Road + Hai-dian District + Beijing 100095 + China + Email: river.huang@huawei.com + + + Loa Andersson + Huawei Technologies Co., Ltd + Stockholm + Sweden + Email: loa@mail01.huawei.com + + + Mach(Guoyi) Chen + Huawei Technologies Co., Ltd + Q14 Huawei Campus + No. 156 Beiqing Road + Hai-dian District + Beijing 100095 + China + Email: mach.chen@huawei.com + + + + + +Hao, et al. Informational [Page 15] + -- cgit v1.2.3