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RTGWG                                                 C. Villamizar, Ed.
Internet-Draft                                                OCCNC, LLC
Intended status: Informational                           D. McDysan, Ed.
Expires: January 12, 2014                                        Verizon
                                                                 S. Ning
                                                     Tata Communications
                                                                A. Malis
                                                                 Verizon
                                                                 L. Yong
                                                              Huawei USA
                                                           July 11, 2013


          Requirements for Advanced Multipath in MPLS Networks
                   draft-ietf-rtgwg-cl-requirement-11

Abstract

   This document provides a set of requirements for Advanced Multipath
   in MPLS Networks.

   Advanced Multipath is a formalization of multipath techniques
   currently in use in IP and MPLS networks and a set of extensions to
   existing multipath techniques.

Status of this Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at http://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on January 12, 2014.

Copyright Notice

   Copyright (c) 2013 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



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   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
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Table of Contents

   1.  Introduction . . . . . . . . . . . . . . . . . . . . . . . . .  3
     1.1.  Requirements Language  . . . . . . . . . . . . . . . . . .  3
   2.  Definitions  . . . . . . . . . . . . . . . . . . . . . . . . .  3
   3.  Functional Requirements  . . . . . . . . . . . . . . . . . . .  6
     3.1.  Availability, Stability and Transient Response . . . . . .  6
     3.2.  Component Links Provided by Lower Layer Networks . . . . .  7
     3.3.  Parallel Component Links with Different Characteristics  .  8
   4.  Derived Requirements . . . . . . . . . . . . . . . . . . . . . 11
   5.  Management Requirements  . . . . . . . . . . . . . . . . . . . 12
   6.  Acknowledgements . . . . . . . . . . . . . . . . . . . . . . . 13
   7.  IANA Considerations  . . . . . . . . . . . . . . . . . . . . . 13
   8.  Security Considerations  . . . . . . . . . . . . . . . . . . . 13
   9.  References . . . . . . . . . . . . . . . . . . . . . . . . . . 14
     9.1.  Normative References . . . . . . . . . . . . . . . . . . . 14
     9.2.  Informative References . . . . . . . . . . . . . . . . . . 14
   Authors' Addresses . . . . . . . . . . . . . . . . . . . . . . . . 15























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1.  Introduction

   There is often a need to provide large aggregates of bandwidth that
   are best provided using parallel links between routers or carrying
   traffic over multiple MPLS LSP.  In core networks there is often no
   alternative since the aggregate capacities of core networks today far
   exceed the capacity of a single physical link or single packet
   processing element.

   The presence of parallel links, with each link potentially comprised
   of multiple layers has resulted in additional requirements.  Certain
   services may benefit from being restricted to a subset of the
   component links or a specific component link, where component link
   characteristics, such as latency, differ.  Certain services require
   that an LSP be treated as atomic and avoid reordering.  Other
   services will continue to require only that reordering not occur
   within a microflow as is current practice.

   The purpose of this document is to clearly enumerate a set of
   requirements related to the protocols and mechanisms that provide
   MPLS based Advanced Multipath.  The intent is to first provide a set
   of functional requirements that are as independent as possible of
   protocol specifications (Section 3).  For certain functional
   requirements this document describes a set of derived protocol
   requirements (Section 4) and management requirements (Section 5).

1.1.  Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC 2119 [RFC2119].

   Any statement which requires the solution to support some new
   functionality through use of [RFC2119] keywords, SHOULD be
   interpretted as follows.  The implementation either MUST or SHOULD
   support the new functionality depending on the use of either MUST or
   SHOULD in the requirements statement.  The implementation SHOULD in
   most or all cases allow any new functionality to be individually
   enabled or disabled through configuration.  A service provider or
   other deployment MAY choose to enable or disable any feature in their
   network, subject to implementation limitations on sets of features
   which can be disabled.


2.  Definitions






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   Multipath
       The term multipath includes all techniques in which

       1.  Traffic can take more than one path from one node to a
           destination.

       2.  Individual packets take one path only.  Packets are not
           subdivided and reassembled at the receiving end.

       3.  Packets are not resequenced at the receiving end.

       4.  The paths may be:

           a.  parallel links between two nodes, or

           b.  may be specific paths across a network to a destination
               node, or

           c.  may be links or paths to an intermediate node used to
               reach a common destination.

       The paths need not have equal capacity.  The paths may or may not
       have equal cost in a routing protocol.

   Advanced Multipath
       Advanced Multipath meets the requirements defined in this
       document.  A key capability of advanced multipath is the support
       of non-homogeneous component links.

   Composite Link
       The term Composite Link had been a registered trademark of Avici
       Systems, but was abandoned in 2007.  The term composite link is
       now defined by the ITU in [ITU-T.G.800].  The ITU definition
       includes multipath as defined here, plus inverse multiplexing
       which is explicitly excluded from the definition of multipath.

   Inverse Multiplexing
       Inverse multiplexing either transmits whole packets and
       resequences the packets at the receiving end or subdivides
       packets and reassembles the packets at the receiving end.
       Inverse multiplexing requires that all packets be handled by a
       common egress packet processing element and is therefore not
       useful for very high bandwidth applications.

   Component Link
       The ITU definition of composite link in [ITU-T.G.800] and the
       IETF definition of link bundling in [RFC4201] both refer to an
       individual link in the composite link or link bundle as a



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       component link.  The term component link is applicable to all
       forms of multipath.  The IEEE uses the term member rather than
       component link in Ethernet Link Aggregation [IEEE-802.1AX].

   Client LSP
       A client LSP is an LSP which has been set up over a server layer.
       In the context of this discussion, a client LSP is a LSP which
       has been set up over a multipath as opposed to an LSP
       representing the multipath itself or any LSP supporting a
       component links of that multipath.

   Flow
       A sequence of packets that should be transferred in order on one
       component link of a multipath.

   Flow identification
       The label stack and other information that uniquely identifies a
       flow.  Other information in flow identification may include an IP
       header, pseudowire (PW) control word, Ethernet MAC address, etc.
       Note that a client LSP may contain one or more Flows or a client
       LSP may be equivalent to a Flow.  Flow identification is used to
       locally select a component link, or a path through the network
       toward the destination.

   Load Balance
       Load split, load balance, or load distribution refers to
       subdividing traffic over a set of component links such that load
       is fairly evenly distributed over the set of component links and
       certain packet ordering requirements are met.  Some existing
       techniques better acheive these objectives than others.

   Performance Objective
       Numerical values for performance measures, principally
       availability, latency, and delay variation.  Performance
       objectives may be related to Service Level Agreements (SLA) as
       defined in RFC2475 or may be strictly internal.  Performance
       objectives may span links, edge-to-edge, or end-to-end.
       Performance objectives may span one provider or may span multiple
       providers.

   A Component Link may be a point-to-point physical link (where a
   "physical link" includes one or more link layer plus a physical
   layer) or a logical link that preserves ordering in the steady state.
   A component link may have transient out of order events, but such
   events must not exceed the network's Performance Objectives.  For
   example, a compoent link may be comprised of any supportable
   combination of link layers over a physical layer or over logical sub-
   layers, including those providing physical layer emulation.



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   The ingress and egress of a multipath may be midpoint LSRs with
   respect to a given client LSP.  A midpoint LSR does not participate
   in the signaling of any clients of the client LSP.  Therefore, in
   general, multipath endpoints cannot determine requirements of clients
   of a client LSP through participation in the signaling of the clients
   of the client LSP.

   The term Advanced Multipath is intended to be used within the context
   of this document and the related documents,
   [I-D.ietf-rtgwg-cl-use-cases] and [I-D.ietf-rtgwg-cl-framework] and
   any other related document.  Other advanced multipath techniques may
   in the future arise.  If the capabilities defined in this document
   become commonplace, they would no longer be considered "advanced".
   Use of the term "advanced multipath" outside this document, if
   refering to the term as defined here, should indicate Advanced
   Multipath as defined by this document, citing the current document
   name.  If using another definition of "advanced multipath", documents
   may optionally clarify that they are not using the term "advanced
   multipath" as defined by this document if clarification is deemed
   helpful.


3.  Functional Requirements

   The Functional Requirements in this section are grouped in
   subsections starting with the highest priority.

3.1.  Availability, Stability and Transient Response

   Limiting the period of unavailability in response to failures or
   transient events is extremely important as well as maintaining
   stability.  The transient period between some service disrupting
   event and the convergence of the routing and/or signaling protocols
   MUST occur within a time frame specified by Performance Objective
   values.

   FR#1  An advanced multipath MAY be announced in conjunction with
         detailed parameters about its component links, such as
         bandwidth and latency.  The advanced multipath SHALL behave as
         a single IGP adjacency.

   FR#2  The solution SHALL provide a means to summarize some routing
         advertisements regarding the characteristics of an advanced
         multipath such that the updated protocol mechanisms maintain
         convergence times within the timeframe needed to meet or no
         significantly exceed existing Performance Objective for
         convergence on the same network or convergence on a network
         with a similar topology.



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   FR#3  The solution SHALL ensure that restoration operations happen
         within the timeframe needed to meet existing Performance
         Objective for restoration time on the same network or
         restoration time on a network with a similar topology.

   FR#4  The solution SHALL provide a mechanism to select a path for a
         flow across a network that contains a number of paths comprised
         of pairs of nodes connected by advanced multipath in such a way
         as to automatically distribute the load over the network nodes
         connected by advanced multipaths while meeting all of the other
         mandatory requirements stated above.  The solution SHOULD work
         in a manner similar to that of current networks without any
         advanced multipath protocol enhancements when the
         characteristics of the individual component links are
         advertised.

   FR#5  If extensions to existing protocols are specified and/or new
         protocols are defined, then the solution SHOULD provide a means
         for a network operator to migrate an existing deployment in a
         minimally disruptive manner.

   FR#6  Any load balancing solutions MUST NOT oscillate.  Some change
         in path MAY occur.  The solution MUST ensure that path
         stability and traffic reordering continue to meet Performance
         Objective on the same network or on a network with a similar
         topology.  Since oscillation may cause reordering, there MUST
         be means to control the frequency of changing the component
         link over which a flow is placed.

   FR#7  Management and diagnostic protocols MUST be able to operate
         over advanced multipaths.

   Existing scaling techniques used in MPLS networks apply to MPLS
   networks which support Advanced Multipaths.  Scalability and
   stability are covered in more detail in
   [I-D.ietf-rtgwg-cl-framework].

3.2.  Component Links Provided by Lower Layer Networks

   A component link may be supported by a lower layer network.  For
   example, the lower layer may be a circuit switched network or another
   MPLS network (e.g., MPLS-TP)).  The lower layer network may change
   the latency (and/or other performance parameters) seen by the client
   layer.  Currently, there is no protocol for the lower layer network
   to inform the higher layer network of a change in a performance
   parameter.  Communication of the latency performance parameter is a
   very important requirement.  Communication of other performance
   parameters (e.g., delay variation) is desirable.



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   FR#8   The solution SHALL specify a protocol means to allow a lower
          layer server network to communicate latency to the higher
          layer client network.

   FR#9   The precision of latency reporting SHOULD be configurable.  A
          reasonable default SHOULD be provided.  Implementations SHOULD
          support precision of at least 10% of the one way latencies for
          latency of 1 ms or more.

   FR#10  The solution SHALL provide a means to limit the latency to
          meet a Performance Objective target on a per flow basis or
          group of flow basis, where flows or groups of flows are
          identifiable in the forwarding plane and are signaled using in
          the control plane or set up using the management plane.

          The Performance Objectives differ across the services, and
          some services have different Performance Objectives for
          different QoS classes, for example, one QoS class may have a
          much larger latency bound than another.  Overload can occur
          which would violate a Performance Objective parameter (e.g.,
          loss) and some remedy to handle this case for an advanced
          multipath is required.

   FR#11  If the total demand offered by traffic flows exceeds the
          capacity of the advanced multipath, the solution SHOULD define
          a means to cause some traffic flows or groups of flows to move
          to some other point in the network that is not congested.
          These "preempted flows" may not be restored if there is no
          uncongested path in the network.

   The intent is to measure the predominant latency in uncongested
   service provider networks, where geographic delay dominates and is on
   the order of milliseconds or more.  The argument for including
   queuing delay is that it reflects the delay experienced by
   applications.  The argument against including queuing delay is that
   it if used in routing decisions it can result in routing instability.
   This tradeoff is discussed in detail in
   [I-D.ietf-rtgwg-cl-framework].

3.3.  Parallel Component Links with Different Characteristics

   As one means to provide high availability, network operators deploy a
   topology in the MPLS network using lower layer networks that have a
   certain degree of diversity at the lower layer(s).  Many techniques
   have been developed to balance the distribution of flows across
   component links that connect the same pair of nodes.  When the path
   for a flow can be chosen from a set of candidate nodes connected via
   advanced multipaths, other techniques have been developed.  Refer to



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   the Appendices in [I-D.ietf-rtgwg-cl-use-cases] for a description of
   existing techniques and a set of references.

   FR#12  The solution SHALL measure traffic flows or groups of traffic
          flows and dynamically select the component link on which to
          place this traffic in order to balance the load so that no
          component link in the advanced multipath between a pair of
          nodes is overloaded.

   FR#13  When a traffic flow is moved from one component link to
          another in the same advanced multipath between a set of nodes
          (or sites), it MUST be done so in a minimally disruptive
          manner.

   FR#14  Load balancing MAY be used during sustained low traffic
          periods to reduce the number of active component links for the
          purpose of power reduction.

   FR#15  The solution SHALL provide a means to identify flows whose
          rearrangement frequency needs to be bounded by a configured
          value and MUST provide a means to bound the rearrangement
          frequency for these flows.

   FR#16  The solution SHALL provide a means that communicates whether
          the flows within an client LSP can be split across multiple
          component links.  The solution SHOULD provide a means to
          indicate the flow identification field(s) which can be used
          along the flow path which can be used to perform this
          function.

   FR#17  The solution SHALL provide a means to indicate that a traffic
          flow will traverse a component link with the minimum latency
          value.

   FR#18  The solution SHALL provide a means to indicate that a traffic
          flow will traverse a component link with a maximum acceptable
          latency value as specified by protocol.

   FR#19  The solution SHALL provide a means to indicate that a traffic
          flow will traverse a component link with a maximum acceptable
          delay variation value as specified by protocol.

   FR#20  The solution SHALL provide a means local to a node that
          automatically distributes flows across the component links in
          the advanced multipath such that Performance Objectives are
          met as described in prior requirements.





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   FR#21  The solution SHALL provide a means to distribute flows from a
          single client LSP across multiple component links to handle at
          least the case where the traffic carried in an client LSP
          exceeds that of any component link in the advanced multipath.
          As defined in Section 2, a flow is a sequence of packets that
          should be transferred on one component link and should be
          transferred in order.

   FR#22  The solution SHOULD support the use case where an advanced
          multipath itself is a component link for a higher order
          advanced multipath.  For example, an advanced multipath
          comprised of MPLS-TP bi-directional tunnels viewed as logical
          links could then be used as a component link in yet another
          advanced multipath that connects MPLS routers.

   FR#23  The solution MUST support an optional means for client LSP
          signaling to bind a client LSP to a particular component link
          within an advanced multipath.  If this option is not
          exercised, then a client LSP that is bound to an advanced
          multipath may be bound to any component link matching all
          other signaled requirements, and different directions of a
          bidirectional client LSP can be bound to different component
          links.

   FR#24  The solution MUST support a means to indicate that both
          directions of co-routed bidirectional client LSP MUST be bound
          to the same component link.

   A minimally disruptive change implies that as little disruption as is
   practical occurs.  Such a change can be achieved with zero packet
   loss.  A delay discontinuity may occur, which is considered to be a
   minimally disruptive event for most services if this type of event is
   sufficiently rare.  A delay discontinuity is an example of a
   minimally disruptive behavior corresponding to current techniques.

   A delay discontinuity is an isolated event which may greatly exceed
   the normal delay variation (jitter).  A delay discontinuity has the
   following effect.  When a flow is moved from a current link to a
   target link with lower latency, reordering can occur.  When a flow is
   moved from a current link to a target link with a higher latency, a
   time gap can occur.  Some flows (e.g., timing distribution, PW
   circuit emulation) are quite sensitive to these effects.  A delay
   discontinuity can also cause a jitter buffer underrun or overrun
   affecting user experience in real time voice services (causing an
   audible click).  These sensitivities may be specified in a
   Performance Objective.

   As with any load balancing change, a change initiated for the purpose



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   of power reduction may be minimally disruptive.  Typically the
   disruption is limited to a change in delay characteristics and the
   potential for a very brief period with traffic reordering.  The
   network operator when configuring a network for power reduction
   should weigh the benefit of power reduction against the disadvantage
   of a minimal disruption.


4.  Derived Requirements

   This section takes the next step and derives high-level requirements
   on protocol specification from the functional requirements.

   DR#1  The solution SHOULD attempt to extend existing protocols
         wherever possible, developing a new protocol only if this adds
         a significant set of capabilities.

   DR#2  A solution SHOULD extend LDP capabilities to meet functional
         requirements (without using TE methods as decided in
         [RFC3468]).

   DR#3  Coexistence of LDP and RSVP-TE signaled LSPs MUST be supported
         on an advanced multipath.  Other functional requirements should
         be supported as independently of signaling protocol as
         possible.

   DR#4  When the nodes connected via an advanced multipath are in the
         same MPLS network topology, the solution MAY define extensions
         to the IGP.

   DR#5  When the nodes are connected via an advanced multipath are in
         different MPLS network topologies, the solution SHALL NOT rely
         on extensions to the IGP.

   DR#6  The solution SHOULD support advanced multipath IGP
         advertisement that results in convergence time better than that
         of advertising the individual component links.  The solution
         SHALL be designed so that it represents the range of
         capabilities of the individual component links such that
         functional requirements are met, and also minimizes the
         frequency of advertisement updates which may cause IGP
         convergence to occur.

         Examples of advertisement update triggering events to be
         considered include: client LSP establishment/release, changes
         in component link characteristics (e.g., latency, up/down
         state), and/or bandwidth utilization.




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   DR#7  When a worst case failure scenario occurs, the number of
         RSVP-TE client LSPs to be resignaled will cause a period of
         unavailability as perceived by users.  The resignaling time of
         the solution MUST support protocol mechanisms meeting existing
         provider Performance Objective for the duration of
         unavailability without significantly relaxing those existing
         Performance Objectives for the same network or for networks
         with similar topology.  For example, the processing load due to
         IGP readvertisement MUST NOT increase significantly and the
         resignaling time of the solution MUST NOT increase
         significantly as compared with current methods.


5.  Management Requirements

   MR#1  Management Plane MUST support polling of the status and
         configuration of an advanced multipath and its individual
         advanced multipath and support notification of status change.

   MR#2  Management Plane MUST be able to activate or de-activate any
         component link in an advanced multipath in order to facilitate
         operation maintenance tasks.  The routers at each end of an
         advanced multipath MUST redistribute traffic to move traffic
         from a de-activated link to other component links based on the
         traffic flow TE criteria.

   MR#3  Management Plane MUST be able to configure a client LSP over an
         advanced multipath and be able to select a component link for
         the client LSP.

   MR#4  Management Plane MUST be able to trace which component link a
         client LSP is assigned to and monitor individual component link
         and advanced multipath performance.

   MR#5  Management Plane MUST be able to verify connectivity over each
         individual component link within an advanced multipath.

   MR#6  Component link fault notification MUST be sent to the
         management plane.

   MR#7  Advanced multipath fault notification MUST be sent to the
         management plane and MUST be distributed via link state message
         in the IGP.

   MR#8  Management Plane SHOULD provide the means for an operator to
         initiate an optimization process.





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   MR#9  An operator initiated optimization MUST be performed in a
         minimally disruptive manner as described in Section 3.3.


6.  Acknowledgements

   Frederic Jounay of France Telecom and Yuji Kamite of NTT
   Communications Corporation co-authored a version of this document.

   A rewrite of this document occurred after the IETF77 meeting.
   Dimitri Papadimitriou, Lou Berger, Tony Li, the former WG chairs John
   Scuder and Alex Zinin, the current WG chair Alia Atlas, and others
   provided valuable guidance prior to and at the IETF77 RTGWG meeting.

   Tony Li and John Drake have made numerous valuable comments on the
   RTGWG mailing list that are reflected in versions following the
   IETF77 meeting.

   Iftekhar Hussain and Kireeti Kompella made comments on the RTGWG
   mailing list after IETF82 that identified a new requirement.
   Iftekhar Hussain made numerous valuable comments on the RTGWG mailing
   list that resulted in improvements to document clarity.

   In the interest of full disclosure of affiliation and in the interest
   of acknowledging sponsorship, past affiliations of authors are noted.
   Much of the work done by Ning So occurred while Ning was at Verizon.
   Much of the work done by Curtis Villamizar occurred while at
   Infinera.  Infinera continues to sponsor this work on a consulting
   basis.

   Tom Yu and Francis Dupont provided the SecDir and GenArt reviews
   respectively.  Both reviews provided useful comments.  Lou Berger
   provided the RtgDir review which resulted in substantial
   clarification of terminology and document wording, particularly in
   the Abstract, Introduction, and Definitions sections.


7.  IANA Considerations

   This memo includes no request to IANA.


8.  Security Considerations

   The security considerations for MPLS/GMPLS and for MPLS-TP are
   documented in [RFC5920] and [RFC6941].  This document does not impact
   the security of MPLS, GMPLS, or MPLS-TP.




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   The additional information that this document requires does not
   provide significant additional value to an attacker beyond the
   information already typically available from attacking a routing or
   signaling protocol.  If the requirements of this document are met by
   extending an existing routing or signaling protocol, the security
   considerations of the protocol being extended apply.  If the
   requirements of this document are met by specifying a new protocol,
   the security considerations of that new protocol should include an
   evaluation of what level of protection is required by the additional
   information specified in this document, such as data origin
   authentication.


9.  References

9.1.  Normative References

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119, March 1997.

9.2.  Informative References

   [I-D.ietf-rtgwg-cl-framework]
              Ning, S., McDysan, D., Osborne, E., Yong, L., and C.
              Villamizar, "Composite Link Framework in Multi Protocol
              Label Switching (MPLS)", draft-ietf-rtgwg-cl-framework-01
              (work in progress), August 2012.

   [I-D.ietf-rtgwg-cl-use-cases]
              Ning, S., Malis, A., McDysan, D., Yong, L., and C.
              Villamizar, "Composite Link Use Cases and Design
              Considerations", draft-ietf-rtgwg-cl-use-cases-01 (work in
              progress), August 2012.

   [IEEE-802.1AX]
              IEEE Standards Association, "IEEE Std 802.1AX-2008 IEEE
              Standard for Local and Metropolitan Area Networks - Link
              Aggregation", 2006, <http://standards.ieee.org/getieee802/
              download/802.1AX-2008.pdf>.

   [ITU-T.G.800]
              ITU-T, "Unified functional architecture of transport
              networks", 2007, <http://www.itu.int/rec/T-REC-G/
              recommendation.asp?parent=T-REC-G.800>.

   [RFC3468]  Andersson, L. and G. Swallow, "The Multiprotocol Label
              Switching (MPLS) Working Group decision on MPLS signaling
              protocols", RFC 3468, February 2003.



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   [RFC4201]  Kompella, K., Rekhter, Y., and L. Berger, "Link Bundling
              in MPLS Traffic Engineering (TE)", RFC 4201, October 2005.

   [RFC5920]  Fang, L., "Security Framework for MPLS and GMPLS
              Networks", RFC 5920, July 2010.

   [RFC6941]  Fang, L., Niven-Jenkins, B., Mansfield, S., and R.
              Graveman, "MPLS Transport Profile (MPLS-TP) Security
              Framework", RFC 6941, April 2013.


Authors' Addresses

   Curtis Villamizar (editor)
   OCCNC, LLC

   Email: curtis@occnc.com


   Dave McDysan (editor)
   Verizon
   22001 Loudoun County PKWY
   Ashburn, VA  20147
   USA

   Email: dave.mcdysan@verizon.com


   So Ning
   Tata Communications

   Email: ning.so@tatacommunications.com


   Andrew Malis
   Verizon
   60 Sylvan Road
   Waltham, MA  02451
   USA

   Phone: +1 781-466-2362
   Email: andrew.g.malis@verizon.com









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   Lucy Yong
   Huawei USA
   5340 Legacy Dr.
   Plano, TX  75025
   USA

   Phone: +1 469-277-5837
   Email: lucy.yong@huawei.com











































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