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Versions: (draft-helvoort-mpls-tp-rosetta-stone) 00 01 02 03 04 05 06 07 08 09 10 11 12 13 RFC 7087

MPLS Working Group                                H. van Helvoort (Ed)
Internet Draft                                     Huawei Technologies
Intended status: Informational
Expires: July 2013                                   L. Andersson (Ed)
                                                             Ericsson

                                                      N. Sprecher (Ed)
                                                Nokia Siemens Networks

                                                      January 15, 2013


        A Thesaurus for the Terminology used in Multiprotocol Label
       Switching Transport Profile (MPLS-TP) drafts/RFCs and ITU-T's
                    Transport Network Recommendations.
                    draft-ietf-mpls-tp-rosetta-stone-08


                          Status of this Memo

   This Internet-Draft is submitted to IETF in full conformance with
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   This Internet-Draft will expire in July 2013.

Copyright Notice

   Copyright (c) 2013 IETF Trust and the persons identified as the
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   This document is subject to BCP 78 and the IETF Trust's Legal
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   document must include Simplified BSD License text as described in
   Section 4.e of the Trust Legal Provisions and are provided without
   warranty as described in the Simplified BSD License.

Abstract

   MPLS-TP is based on a profile of the MPLS and PW procedures as
   specified in the MPLS-TE and (MS-)PW architectures developed by the
   IETF.  The ITU-T has specified a Transport Network architecture.

   This document provides a thesaurus for the interpretation of MPLS-TP
   terminology within the context of the ITU-T Transport Network
   recommendations.

   It is important to note that MPLS-TP is applicable in a wider set of
   contexts than just Transport Networks.  The definitions presented in
   this document do not provide exclusive nor complete interpretations
   of MPLS-TP concepts.  This document simply allows the MPLS-TP terms
   to be applied within the Transport Network context.



Table of Contents

   1. Introduction  4
      1.1. Contributing Authors 4
      1.2. Abbreviations 4
      SCC  Signaling Communication Channel 5
   2. Terminology 5
      2.1. MPLS-TP Terminology Sources  5
      2.2. ITU-T Transport Network Terminology Sources 5
      2.3. Common Terminology Sources 5
   3. Thesaurus  6
      3.1. Associated bidirectional path:  6
      3.2. Bidirectional path: 6
      3.3. Client layer network:  6
      3.4. Concatenated Segment:  6
      3.5. Control Plane: 6
      3.6. Co-routed bidirectional path: 7
      3.7. Domain: 7
      3.8. Layer network: 7
      3.9. Link: 7
      3.10. MPLS-TP Logical Ring:  8
      3.11. MPLS-TP Physical Ring: 8
      3.12. MPLS-TP Ring Topology: 8
      3.13. Path: 8
      3.14. Section Layer Network: 8


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      3.15. Segment: 9
      3.16. Server layer: 9
      3.17. Span: 9
      3.18. Sublayer:  9
      3.19. Tandem Connection:  9
      3.20. Transport Network:  9
      3.21. Transport path:  10
      3.22. Transport path layer:  10
      3.23. Transport service layer:  10
      3.24. Transmission media layer: 10
      3.25. Unidirectional path: 10
      3.26. Failure: 10
      3.27. Fault:  11
      3.28. Defect: 11
      3.29. MPLS Transport Profile (MPLS-TP):  11
      3.30. MPLS Section: 11
      3.31. MPLS-TP NE: 11
      3.32. MPLS-TP network: 11
      3.33. Equipment Management Function (EMF):  11
      3.34. Data Communication Network (DCN):  11
      3.35. Communication Channel (CC):  12
      3.36. Embedded Communication Channel (ECC): 12
      3.37. Management Communication Channel (MCC):  12
      3.38. Management Communication Network (MCN):  12
      3.39. Signaling Communication Channel (SCC): 12
      3.40. Signaling Communication Network (SCN): 12
      3.41. Operations System (OS): 12
      3.42. OAM flow:  12
      3.43. Maintenance Entity Group (MEG): 13
      3.44. Maintenance Entity (ME):  13
      3.45. Maintenance Entity Group End Point (MEP): 13
      3.46. Maintenance Entity Group Intermediate Point (MIP): 14
      3.47. Server MEPs:  14
      3.48. Link recovery: 15
      3.49. Segment recovery: 15
      3.50. End-to-end recovery: 15
      3.51. Transport Entity: 15
      3.52. Working Entity:  15
      3.53. Protection Entity:  15
      3.54. Recovery entity: 15
   4. Guidance on the Application of this Thesaurus  16
   5. Management Considerations 16
   6. Security Considerations 16
   7. IANA Considerations 16
   8. Acknowledgments  17
   9. References 17
      9.1. Normative References 17


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      9.2. Informative References 18


1.   Introduction

   Multiprotocol Label Switching - Transport Profile (MPLS-TP) has been
   developed by the IETF to facilitate the Operation, Administration
   and Management of Label Switched Paths (LSPs) in a Transport Network
   environment as defined by the ITU-T.

   The ITU-T has specified a Transport Network architecture for the
   transfer of signals from different technologies.  This architecture
   forms the basis of many Recommendations within the ITU-T.

   Because of the difference in historic background of MPLS, and
   inherently MPLS-TP (the Internet) and the Transport Network (ITU
   telecommunication Sector), the terminology used is different.

   This document provides a thesaurus for the interpretation of ITU-T
   Transport Network terminology within the context of the MPLS-TP.
   This allows MPLS-TP documents to be generally understood by those
   familiar with MPLS RFCs.  The definitions presented in this document
   do not provide exclusive or complete interpretations of the ITU-T
   Transport Network concepts.

1.1.  Contributing Authors

   Italo Busi, Ben Niven-Jenkins, Enrique Hernandez-Valencia, Lieven
   Levrau, Dinesh Mohan, Stuart Bryant, Dan Frost, Matthew Bocci,
   Vincenzo Sestito, Vigoureux, Yaacov Weingarten

1.2.  Abbreviations

   CC   Communications Channel

   DCN  Data Communication Network

   ECC  Embedded Communication Channel

   EMF  Equipment Management Function

   MCC  Management Communication Channel

   MCN  Management Communication Network

   ME   Maintenance Entity



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   MEG  ME Group

   MEP  MEG End Point

   MIP  MEG Intermediate Point

   MPLS Multiprotocol Label Switching

   MPLS-TP MPLS Transport Profile

   NE   Network Element

   OAM  Operations, Administration and Maintenance

   O&M  OAM and Management

   SCC  Signaling Communication Channel

   SCN  Signaling Communication Network



2.   Terminology

2.1.  MPLS-TP Terminology Sources

   MPLS-TP terminology is principally defined in [RFC3031].  Other
   documents provide further key definitions including [RFC4397], and
   [RFC....].

2.2.  ITU-T Transport Network Terminology Sources

   The ITU-T Transport Network is specified in a number of
   recommendations:  generic functional architectures and requirements
   are specified in Error! Reference source not found., Error!
   Reference source not found., and Error! Reference source not found..
   ITU-T Recommendation Error! Reference source not found. contains an
   overview of the Terms and Definitions for transport MPLS.

2.3.  Common Terminology Sources

   The work in this document builds on the shared view of MPLS
   requirements.

   The following sources are used:
   IETF framework and requirements RFCs: [RFC6371], [RFC6372],
   [RFC5654], [RFC5921], [RFC5860], [RFC5951], [RFC3031] and [RFC4397].


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   ITU-T architecture and requirements Recommendations: [ITU-T_G.8101],
   [ITU-T_G.805], [ITU-T_G.806], [ITU-T_G.872], [ITU-T G.7710] and
   [ITU-T Y.2611]



3.   Thesaurus

3.1.  Associated bidirectional path:

   A path that supports traffic flow in both directions but that is
   constructed from a pair of unidirectional paths (one for each
   direction) that are associated with one another at the path's
   ingress/egress points.  The forward and backward directions are
   setup, monitored, and protected independently.  As a consequence,
   they may or may not follow the same route (links and nodes) across
   the network.

3.2.  Bidirectional path:

   A path that supports traffic flow in two opposite directions, i.e.
   the forward and backward direction.

3.3.  Client layer network:

   In a client/server relationship (see Error! Reference source not
   found.), the client layer network receives a (transport) service
   from the lower server layer network (usually the layer network under
   consideration).

3.4.  Concatenated Segment:

   A serial-compound link connection as defined in Error! Reference
   source not found..  A concatenated segment is a contiguous part of
   an LSP or multi-segment PW that comprises a set of segments and
   their interconnecting nodes in sequence.  See also "Segment".

3.5.  Control Plane:

   Within the scope of [RFC5654], the control plane performs transport
   path control functions.  Through signalling, the control plane sets
   up, modifies and releases transport paths, and may recover a
   transport path in case of a failure.  The control plane also
   performs other functions in support of transport path control, such
   as routing information dissemination.




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3.6.  Co-routed bidirectional path:

   A path where the forward and backward directions follow the same
   route (links and nodes) across the network.  Both directions are
   setup, monitored and protected as a single entity.  A transport
   network path is typically co-routed.

3.7.  Domain:

   A domain represents a collection of entities (for example network
   elements) that are grouped for a particular purpose, examples of
   which are administrative and/or managerial responsibilities, trust
   relationships, addressing schemes, infrastructure capabilities,
   aggregation, survivability techniques, distributions of control
   functionality, etc.  Examples of such domains include IGP areas and
   Autonomous Systems.

3.8.  Layer network:

   Layer network is defined in Error! Reference source not found..  A
   layer network provides for the transfer of client information and
   independent operation of the client OAM.  A layer network may be
   described in a service context as follows: one layer network may
   provide a (transport) service to a higher client layer network and
   may, in turn, be a client to a lower-layer network.  A layer network
   is a logical construction somewhat independent of arrangement or
   composition of physical network elements.  A particular physical
   network element may topologically belong to more than one layer
   network, depending on the actions it takes on the encapsulation
   associated with the logical layers (e.g., the label stack), and thus
   could be modeled as multiple logical elements.  A layer network may
   consist of one or more sublayers. For additional explanation of how
   layer networks relate to the OSI concept of layering, see Appendix I
   of Error! Reference source not found..

3.9.  Link:

   A physical or logical connection between a pair of LSRs that are
   adjacent at the (sub)layer network under consideration.  A link may
   carry zero, one or more LSPs or PWs.  A packet entering a link will
   emerge with the same label stack entry values.

   A link as defined in Error! Reference source not found. is used to
   describe a fixed relationship between two ports.





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3.10.   MPLS-TP Logical Ring:

   An MPLS-TP logical ring is constructed from a set of LSRs and
   logical data links (such as MPLS-TP LSP tunnels or MSPL-TP
   pseudowires) and physical data links that form a ring topology.

3.11.   MPLS-TP Physical Ring:

   An MPLS-TP physical ring is constructed from a set of LSRs and
   physical data links that form a ring topology.

3.12.   MPLS-TP Ring Topology:

   In an MPLS-TP ring topology, each LSR is connected to exactly two
   other LSRs, each via a single point-to-point bidirectional MPLS-TP
   capable link.  A ring may also be constructed from only two LSRs
   where there are also exactly two links.  Rings may be connected to
   other LSRs to form a larger network.  Traffic originating or
   terminating outside the ring may be carried over the ring.  Client
   network nodes (such as CEs) may be connected directly to an LSR in
   the ring.

3.13.   Path:

   See Transport path.

3.14.   Section Layer Network:

   A section layer is a server layer (which may be MPLS-TP or a
   different technology) that provides for the transfer of the section-
   layer client information between adjacent nodes in the transport-
   path layer or transport-service layer.  A section layer may provide
   for aggregation of multiple MPLS-TP clients.  Note that Error!
   Reference source not found. defines the section layer as one of the
   two layer networks in a transmission-media layer network.  The other
   layer network is the physical-media layer network.

   Section layer networks are concerned with all the functions which
   provide for the transfer of information between locations in path
   layer networks.

   Physical media layer networks are concerned with the actual fibres,
   metallic wires or radio frequency channels which support a section
   layer network.





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3.15.   Segment:

   A link connection as defined in Error! Reference source not found..
   A segment is the part of an LSP that traverses a single link or the
   part of a PW that traverses a single link (i.e., that connects a
   pair of adjacent {Switching|Terminating} Provider Edges).  See also
   "Concatenated Segment".

3.16.   Server layer:

   A layer network in which transport paths are used to carry a
   customer's (individual or bundled) service (may be point-to-point,
   point-to-multipoint or multipoint-to-multipoint services).

   In a client/server relationship (see Error! Reference source not
   found.).  the server layer network provides a (transport) service to
   the higher client layer network (usually the layer network under
   consideration).

3.17.   Span:

   A span is synonymous with a link.

3.18.   Sublayer:

   Sublayer is defined in Error! Reference source not found..  The
   distinction between a layer network and a sublayer is that a
   sublayer is not directly accessible to clients outside of its
   encapsulating layer network and offers no direct transport service
   for a higher layer (client) network.

3.19.   Tandem Connection:

   A tandem connection is an arbitrary part of a transport path that
   can be monitored (via OAM) independently from the end-to-end
   monitoring (OAM).  It may be a monitored segment, a monitored
   concatenated segment or any other monitored ordered sequence of
   contiguous hops and/or segments (and their interconnecting nodes) of
   a transport path.

3.20.   Transport Network:

   A Transport Network provides transmission of traffic between
   attached client devices by establishing and maintaining point-to-
   point or point-to-multipoint connections between such devices.  A
   Transport Network is independent of any higher-layer network that
   may exist between clients, except to the extent required to supply


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   this transmission service. In addition to client traffic, a
   Transport Network may carry traffic to facilitate its own operation,
   such as that required to support connection control, network
   management, and Operations, Administration and Maintenance (OAM)
   functions.

3.21.   Transport path:

   A network connection as defined in Error! Reference source not
   found..  In an MPLS-TP environment a transport path corresponds to
   an LSP or a PW.

3.22.   Transport path layer:

   A (sub)layer network that provides point-to-point or point-to-
   multipoint transport paths.  It provides OAM that is independent of
   the clients that it is transporting.

3.23.   Transport service layer:

   A layer network in which transport paths are used to carry a
   customer's (individual or bundled) service (may be point-to-point,
   point-to-multipoint or multipoint-to-multipoint services).

3.24.   Transmission media layer:

   A layer network, consisting of a section layer network and a
   physical layer network as defined in Error! Reference source not
   found., that provides sections (two-port point-to-point connections)
   to carry the aggregate of network-transport path or network-service
   layers on various physical media.

3.25.   Unidirectional path:

   A Unidirectional Path is a path that supports traffic flow in only
   one direction.

3.26.   Failure:

   The fault cause persisted long enough to consider the ability of an
   item to perform a required function to be terminated. The item may
   be considered as failed; a fault has now been detected.  See also
   Error! Reference source not found..






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3.27.   Fault:

   A Fault is the inability of a function to perform a required action.
   This does not include an inability due to preventive maintenance,
   lack of external resources, or planned actions.  See also Error!
   Reference source not found..

3.28.   Defect:

   The situation for which the density of anomalies has reached a level
   where the ability to perform a required function has been
   interrupted. Defects are used as input for PM, the control of
   consequent actions, and the determination of fault cause. See also
   Error! Reference source not found..

3.29.   MPLS Transport Profile (MPLS-TP):

   The set of MPLS functions used to support packet transport services
   and network operations.

3.30.   MPLS Section:

   A network segment between two LSRs that are immediately adjacent at
   the MPLS layer.

3.31.   MPLS-TP NE:

   A network element (NE) that supports MPLS-TP functions.

3.32.   MPLS-TP network:

   A network in which MPLS-TP NEs are deployed

3.33.   Equipment Management Function (EMF):

   The management functions within an NE. See Error! Reference source
   not found..

3.34.   Data Communication Network (DCN):

   A network that supports Layer 1 (physical layer), Layer 2 (data-link
   layer), and Layer 3 (network layer) functionality for distributed
   management communications related to the management plane, for
   distributed signaling communications related to the control plane,
   and other operations communications (e.g., order-wire/voice
   communications, software downloads, etc.).



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3.35.   Communication Channel (CC):

   A logical channel between network elements (NEs) that can be used -
   e.g. - for management plane application or control plane
   applications. The physical channel supporting the CC is technology
   specific.  See [RFC5951] APPENDIX A

3.36.   Embedded Communication Channel (ECC):

   A logical operations channel between network elements (NEs) that can
   be utilized by multiple applications (e.g., management plane
   applications, control plane applications, etc.). The physical
   channel supporting the ECC is technology specific. An example of
   physical channels supporting the ECC is a DCC channel within SDH.

3.37.   Management Communication Channel (MCC):

   A CC dedicated for management plane communications.

3.38.   Management Communication Network (MCN):

   A DCN supporting management plane communication is referred to as a
   Management Communication Network (MCN).

3.39.   Signaling Communication Channel (SCC):

   A CC dedicated for control plane communications. The SCC may be used
   for GMPLS/ASON signaling and/or other control plane messages (e.g.,
   routing messages).

3.40.   Signaling Communication Network (SCN):

   A DCN supporting control plane communication is referred to as a
   Signaling Communication Network (SCN).

3.41.   Operations System (OS):

   A system that performs the functions that support processing of
   information related to operations, administration, maintenance, and
   provisioning (OAM&P) for the networks, including surveillance and
   testing functions to support customer access maintenance.

3.42.   OAM flow:

   An OAM flow is the set of all OAM packets originating with a
   specific source MEP that instrument one direction of a MEG (or
   possibly both in the special case of data plane loopback).


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3.43.   Maintenance Entity Group (MEG):

   A Maintenance Entity Group is defined, for the purpose of connection
   monitoring, between a set of connection points within a connection.
   This set of connection points may be located at the boundary of one
   administrative domain or a protection domain, or the boundaries of
   two adjacent administrative domains. The MEG may consist of one or
   more Maintenance Entities (ME).

   In an MPLS-TP layer network an MEG consists of only one ME.

3.44.   Maintenance Entity (ME):

   A Maintenance Entity can be viewed as the association of two (or
   more) MEG End Points (MEPs), that should be configured and managed
   in order to bound the OAM responsibilities of an OAM flow across a
   network or sub-network, i.e. a transport path or segment, in the
   specific layer network that is being monitored and managed.

   A Maintenance Entity may be defined to monitor and manage
   bidirectional or unidirectional point-to-point connectivity or
   point-to-multipoint connectivity in an MPLS-TP layer network.

   Therefore, in the context of MPLS-TP LSP or PW Maintenance Entity
   (defined below) LERs and T-PEs can be MEPs while LSRs and S-PEs can
   be MIPs. In the case of Tandem Connection Maintenance Entity
   (defined below), LSRs and S-PEs can be either MEPs or MIPs.

   The following properties apply to all MPLS-TP MEs:

   o OAM entities can be nested but not overlapped.

   o Each OAM flow is associated to a unique Maintenance Entity.

   o OAM packets are subject to the same forwarding treatment as the
      data traffic, but they are distinct from the data traffic.

3.45.   Maintenance Entity Group End Point (MEP):

   Maintenance Entity Group End Points (MEPs) are the end points of a
   pre-configured (through the management or control planes) ME.  MEPs
   are responsible for activating and controlling all of the OAM
   functionality for the ME. A MEP may initiate an OAM packet to be
   transferred to its corresponding MEP, or to an intermediate MIP that
   is part of the ME.




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   A MEP terminates all the OAM packets that it receives corresponding
   to its ME and does not forward them further along the path.

   All OAM packets coming to a MEP source are tunnelled via label
   stacking and are not processed within the ME as they belong either
   to the client network layers or to an higher TCM level.

   A MEP in a tandem connection is not coincident with the termination
   of the MPLS-TP transport path (LSP or PW), though it can monitor its
   connectivity (e.g. count packets). A MEP of an MPLS-TP network
   transport path is coincident with transport path termination and
   monitors its connectivity (e.g. count packets).

   MPLS-TP MEP notifies a fault indication to the MPLS-TP client layer
   network.

3.46.   Maintenance Entity Group Intermediate Point (MIP):

   A Maintenance Entity Group Intermediate Point (MIP) is a point
   between the two MEPs in an ME and is capable of responding to some
   OAM packets and forwarding all OAM packets while ensuring fate
   sharing with data plane packets.  A MIP responds only to OAM packets
   that are sent on the ME it belongs to and that are addressed to the
   MIP, it does not initiate OAM messages.

3.47.   Server MEPs:

   A server MEP is a MEP of an ME that is defined in a layer network
   below the MPLS-TP layer network being referenced. A server MEP
   coincides with either a MIP or a MEP in the client (MPLS-TP) layer
   network.

   For example, a server MEP can be either:

   . A termination point of a physical link (e.g. 802.3), an SDH VC or
     OTH ODU for the MPLS-TP Section layer network, defined in
     [RFC6371] section 3.1.;

   . An MPLS-TP Section MEP for MPLS-TP LSPs, defined in [RFC6371]
     section 3.2.;

   . An MPLS-TP LSP MEP for MPLS-TP PWs, defined in [RFC6371] section
     3.4.;

   . An MPLS-TP TCM MEP for higher-level TCMs, defined in [RFC6371]
     sections 3.3. and 3.5.



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   The server MEP can run appropriate OAM functions for fault
   detection, and notifies a fault indication to the MPLS-TP layer
   network.

3.48.   Link recovery:

   MPLS-TP link recovery refers to the recovery of an individual link
   (and hence all or a subset of the LSPs routed over the link) between
   two MPLS-TP nodes. For example, link recovery may be provided by
   server layer recovery.

3.49.   Segment recovery:

   Segment recovery refers to the recovery of an LSP segment (i.e.,
   segment and concatenated segment in the language of [RFC5654])
   between two nodes and is used to recover from the failure of one or
   more links or nodes.

3.50.   End-to-end recovery:

   End-to-end recovery refers to the recovery of an entire LSP, from
   its ingress to its egress node.

3.51.   Transport Entity:

   A "Transport Entity" is a node, link, transport path segment,
   concatenated transport path segment, or entire transport path.

3.52.   Working Entity:

   A "Working Entity" is a transport entity that carries traffic during
   normal network operation.

3.53.   Protection Entity:

   A "Protection Entity" is a transport entity that is pre-allocated
   and used to protect and transport traffic when the working entity
   fails.

3.54.   Recovery entity:

   A "Recovery Entity" is a transport entity that is used to recover
   and transport traffic when the working entity fails.






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4.   Guidance on the Application of this Thesaurus

   As discussed in the introduction to this document, this thesaurus is
   intended to bring the concepts and terms associated with MPLS-TP
   into the context of the ITU-T's Transport Network architecture.
   Thus, it should help those familiar with MPLS to see how they may
   use the features and functions of the Transport Network in order to
   meet the requirements of MPLS-TP.

   This lexicography should not be used in order to obtain or derive
   definitive definitions of GMPLS terms.  To obtain definitions of
   GMPLS terms that are applicable across all GMPLS architectural
   models, the reader should refer to the RFCs listed in the references
   sections of this document.  [RFC3945] provides an overview of the
   GMPLS architecture and should be read first.



5.   Management Considerations

   The MPLS-TP based network requires management. The MPLS-TP
   specifications include considerable efforts to provide operator
   control and monitoring, as well as Operations and Management (OAM)
   functionality.

   These concepts are, however, out of scope of this document.



6.   Security Considerations

   Security is also a significant requirement of MPLS-TP.

   However, this informational document is intended only to provide a
   lexicography, and the security concerns are, therefore, out of
   scope.



7.   IANA Considerations

   To be incorporated in a future revision of this document

   <<TBA>>





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8.   Acknowledgments

   The authors would like to thank all members of the teams (the Joint
   Working Team, the MPLS Interoperability Design Team in IETF and the
   MPLS-TP Ad Hoc Group in ITU-T) involved in the definition and
   specification of MPLS Transport Profile.



9.   References

9.1.  Normative References

   [RFC6371] Busi, I., Allan, D., "Operations, Administration, and
             Maintenance Framework for MPLS-Based Transport Networks",
             September 2011

   [RFC6372] Sprecher, N., Farrel, A., "MPLS Transport Profile (MPLS-
             TP) Survivability Framework", September 2011

   [RFC5654] B. Niven-Jenkins, et al., "Requirements of an MPLS
             Transport Profile", September 2009

   [RFC5921] Bocci, M., Bryant, S., Levrau, L., "A Framework for MPLS
             in Transport Networks", July 2010

   [RFC5860] Vigoureux, M., Betts, M., Ward, D., "Requirements for OAM
             in MPLS Transport Networks", May 2010

   [RFC5951] Gray, E., Mansfield, S., et al., "MPLS TP Network
             Management Requirements", September 2010

   [RFC3031] E. Rosen, et al., "Requirements of an MPLS Transport
             Profile", january 2001

   For information on the availability of the following documents,
   please see http://www.itu.int

   [ITU-T_G.8101] ITU-T Recommendation G.8101/Y.1355 (12/2006), Terms
                  and definitions for transport MPLS.

   [ITU-T_G.805] ITU-T Recommendation G.805 (03/2000), Generic
                  functional architecture of transport networks.

   [ITU-T_G.806] ITU-T Recommendation G.806 (03/2006), Characteristics
                  of transport equipment - Description methodology and
                  generic functionality.


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   [ITU-T_G.872] ITU-T Recommendation G.872 (11/2001), Architecture of
                  optical transport networks.

   [ITU-T G.7710] ITU-T Recommendation G.7710 (07/2007), Common
                  equipment management function requirements

   [ITU-T Y.2611] ITU-T Recommendation Y.2611 (12/2006), High-level
                  architecture of future packet-based networks

9.2.  Informative References

   [RFC4397] I. Bryskin, A. Farrel, "A Lexicography for the
              Interpretation of Generalized Multiprotocol Label
              Switching (GMPLS) Terminology within the Context of the
              ITU-T's Automatically Switched Optical Network (ASON)
              Architecture", february 2006

   [RFC3945] E. Mannie, "Generalized Multi-Protocol Label Switching
             (GMPLS) Architecture", October 2004



Authors' Addresses

   Huub van Helvoort (Editor)
   Huawei Technologies Co., Ltd.
   Email: Huub.van.Helvoort@huawei.com


   Loa Andersson (Editor)
   Ericsson
   Email: loa.andersson@ericsson.com

   Nurit Sprecher (Editor)
   Nokia Siemens Networks
   Email: nurit.sprecher@nsn.com




Contributing Authors' Addresses








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