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Versions: 00 01 02 03 04 05 06 07                                       
INTERNET-DRAFT                                   Tomohiro Otani (Editor)
Intended Status: Informational                    Kenichi Ogaki (Editor)
Expires: September 2007                                    KDDI R&D Labs
                                                    Daniel King (Editor)
                                                           Aria Networks

                                                              March 2007

      Considering Generalized Multiprotocol Label Switching Traffic
          Engineering Attributes During Path Computation

         Document: draft-otani-ccamp-gmpls-cspf-constraints-05.txt


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Copyright Notice

   Copyright (C) The IETF Trust (2007). All Rights Reserved.

Abstract

   This document provides guidelines for the consideration of
   Generalized Multiprotocol Label Switching (GMPLS) Traffic-
   Engineering (TE) attributes for computation of routes for Label
   Switched Paths (LSPs) in a GMPLS network.

   This document summarizes how GMPLS TE attributes on ingress links,
   transit links, and egress links may be treated as path computation
   constraints to determine the route of a GMPLS Label Switched Path.


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Table of Contents

   1. Introduction.................................................... 2
   2. Assumed Network Model........................................... 3
    2.1 GMPLS TE Attributes Consideration for Path Calculation ....... 3
    2.2 Considered Network Model...................................... 3
   3. Path Computation Considerations................................. 4
    3.1. TDM-Switch Capable........................................... 5
    3.2. Lambda Switch Capable (LSC).................................. 6
    3.3. Fiber Switch Capable (FSC)................................... 9
    3.4. Layer 2 Switch Capable (L2SC)............................... 12
    3.5. Packet Switch Capable (PSC)................................. 12
   4. Security Consideration......................................... 12
   5. IANA Considerations............................................ 13
   6. Acknowledgements............................................... 13
   7. Intellectual Property Considerations........................... 13
   8. References..................................................... 13
    8.1 Normative References......................................... 13
    8.2 Informative References....................................... 14

Terminology

   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 [RFC2119].

1. Introduction

   A network is, in general, controlled and managed taking into account
   various attributes of the underlying technologies of the physical and
   logical links and nodes. In a network operated using Generalized
   Multiprotocol Label Switching (GMPLS) protocols, many of these
   Traffic Engineering (TE) attributes are advertised using routing
   protocols [RFC3945], [RFC4202].

   To establish a GMPLS Label Switched Path (LSP) it is necessary to
   compute a route or path for that LSP either hop-by-hop or by the
   pre-calculation of part or all of the path. In order that the route
   selected is capable of satisfying the requirements of the user or
   application that will use the LSP the computation must be constrained
   by a set of LSP-specific requirements and the TE attributes
   advertised within the network. Further, considerations of technology
   and node or link capabilities may also provide restrictions to the
   feasibility of LSP establishment on certain routes, and this can be
   deduced from the TE attributes advertised within the network and used
   by the path computation algorithms to select only viable routes.

   In a mixed, integrated network (for example, one containing optical
   switches and packet routers) these constraints may vary and are
   understood differently for different equipment and different LSPs.

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   This document provides guidelines to facilitate path computation for
   GMPLS LSPs by summarizing how GMPLS TE attributes on ingress links,
   transit links, and egress links may be treated as path computation
   constraints to determine the route of a GMPLS Label Switched Path.

2. Assumed Network Model

2.1 GMPLS TE Attributes Consideration for Path Calculation

   For path computation to establish GMPLS LSPs correctly, various
   GMPLS attributes [RFC4202], [RFC4203] of links as well as
   nodes, as indicated below, must be taken into account in a GMPLS
   network environment in addition to TE attributes of packet based
   network [RFC3630].

   (1) Encoding-type: Synchronous Optical Network(SONET)/Synchronous
       Digital Hierarchy (SDH), Lambda, Ethernet, etc.
   (2) Switching capability: Time Division Multiplex (TDM), Lambda,
       Fiber, etc.
   (3) Bandwidth: OC-192, OC-48, GbE, 10GbE, etc.

   These logical attributes have a very tight relationship with
   underlying physical technologies such as SONET/SDH, Optical Transport
   Network (OTN) or Ethernet in terms of links, and all-optical
   switches, SONET/SDH-basis digital cross connect or electrical-basis
   optical switches in terms of nodes.  Therefore, the GMPLS LSPs must
   satisfy logical constrains as well as corresponding physical
   constraints.  These constraints are sometimes differently understood
   among different layers, and a logically computed GMPLS LSP may
   violate the physical constraints, therefore, a consistent guideline
   to solve this issue should be formulated.

2.2 Considered Network Model

   Figure 1 depicts a typical GMPLS network, consisting of an ingress
   link, a transit link as well as an egress link, to investigate a
   consistent guideline for GMPLS path computation. Each link
   at each interface has its own switching capability, encoding type
   and bandwidth.
   The consideration here is based on a single domain GMPLS network, but
   the analysis maybe applicable to an inter-domain GMPLS networks.

             Ingress             Transit             Egress
   +-----+   link1-2   +-----+   link2-3   +-----+   link3-4   +-----+
   |Node1|------------>|Node2|------------>|Node3|------------>|Node4|
   |     |<------------|     |<------------|     |<------------|     |
   +-----+   link2-1   +-----+   link3-2   +-----+   link4-3   +-----+

                       Figure 1: GMPLS Network Model


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   For the simplicity of the analysis in path consideration, the below
   basic assumptions are made when the LSP is created.

       (1) Switching capabilities (SC) of outgoing links from the
           ingress and egress nodes (link1-2 and link4-3 in Figure 1)
           must be consistent with each other.

       (2) SC of all transit links including incoming links to the
           ingress and egress nodes (link2-1 and link3-4) should be
           consistent with switching type of a LSP to be created.
       (3) Encoding-types of all transit links should be consistent
           with encoding type of a LSP to be created.

   A GMPLS network maybe a multi-layer network, which is composed of
   multiple nodes with different switching capabilities and interface
   encoding types. Therefore, a hierarchical structure may be considered
   in path computation. In such a case, the combination between the
   switching type and encoding type of a desired LSP, and those of all
   transit links described as the table in following section may be
   acceptable. One of advertised multiple interface switching capability
   descriptors for the same link [RFC4202] should be also appropriately
   chosen as the attribute for the link.

   Bandwidth of each TE link is maximum LSP bandwidth in interface
   switching capability descriptor at the priority for a desired LSP
   [RFC4203], and encoding-types of incoming and outgoing links on the
   same interface (for example, link1-2 and link2-1) should be
   consistent with each other.

   In case that the network is comprised of numbered links and
   unnumbered links [RFC3477], an ingress node, who is able to support
   numbered links and unnumbered links may choose both links being part
   of the same desired LSP.

3. Path Computation Considerations

   In this section, we consider GMPLS constraints to be satisfied in
   different cases of link attributes. When a LSP indicated in below
   tables is created, the path computation must choose the route so
   as to satisfy switching capability, encoding type and bandwidth at
   the ingress link, transiting links and the egress link indicated in
   columns next to the created LSP, considering underlying physical
   constraints. Here, almost cases of GMPLS path computation
   consideration are summarized in this document, however, some cases
   will be added in a future version.






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3.1. TDM-Switch Capable

          Table 1: Desired GMPLS Attributes in the Case of TDM-SC

   +-------------+---------+------------+---------+------------------+
   |LSP attribute|Ingress  |Transit     |Egress   |Remarks           |
   +---+---------+---------+------------+---------+------------------+
   |   |         |TDM      |            |TDM      |                  |
   |   |         +---------+            +---------+                  |
   |SC*|TDM      |L2SC     |TDM         |L2SC     |                  |
   |   |         +---------+            +---------+                  |
   |   |         |PSC      |            |PSC      |                  |
   +---+---------+---------+------------+---------+                  |
   |   |SONET/SDH|SONET/SDH|SONET/SDH   |SONET/SDH|Specified in G.691|
   |   +---------+---------+------------+---------+                  |
   |Enc|Ethernet |Ethernet |SONET/SDH   |Ethernet |Specified in IEEE |
   |   |         |         |or Ethernet |         |                  |
   |   +---------+---------+------------+---------+                  |
   |   |OTN*     |OTN      |OTN         |OTN      |                  |
   +---+---------+---------+------------+---------+                  |
   |BW*|X        |<=bw*    |<=bw*       |<=bw*    |                  |
   +---+---------+---------+------------+---------+------------------+

   * SC in LSP means a desired switching type of LSP.
   * OTN interfaces are equivalent to digital wrapper technology in this
     document.
   * BW is the desired bandwidth of the LSP
   * bw is the bandwidth available on the link

   In this case, since the interface with TDM SC supports sub-rate
   switching, BW X can be equal to or less than bw of ingress, transit
   and egress links, and must be larger than the minimum LSP bandwidth
   in the interface switching capability descriptor. Sub-rate
   switching is unsuited for a hierarchical LSP, because the lower-layer
   link usually has larger granular bandwidth than that layer except
   PSC-x, for example a TDM LSP with the desired bandwidth of OC-12
   should not use a lambda switching capable link with the bandwidth of
   OC-48 as a transit link. In such a case, a lambda LSP is created in
   the lower  (lambda) layer in advance, and may be advertised as a TDM
   TE link.











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3.2. Lambda Switch Capable (LSC)

        Table 2.1: The Case of End-Point(Ingress/Egress) Link Attributes
                          Without Lambda Encoding

   +-------------+---------+------------+---------+------------------+
   |LSP attribute|Ingress  |Transit     |Egress   |Remarks           |
   +---+---------+---------+------------+---------+------------------+
   |   |         |LSC      |            |LSC      |                  |
   |   |         +---------+            +---------+                  |
   |SC |LSC      |TDM      |LSC         |TDM      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |L2SC     |            |L2SC     |                  |
   |   |         +---------+            +---------+                  |
   |   |         |PSC      |            |PSC      |                  |
   +---+---------+---------+------------+---------+[RFC4202]         |
   |   |SONET/SDH|SONET/SDH|SONET/SDH   |SONET/SDH|section 3.6, 3.9  |
   |   |         |         |or lambda   |         |Specified in G.691|
   |   +---------+---------+------------+---------+                  |
   |Enc|Ethernet |Ethernet |Ethernet    |Ethernet |Specified in IEEE |
   |   |         |         |or lambda   |         |                  |
   |   +---------+---------+------------+---------+                  |
   |   |OTN      |OTN      |OTN         |OTN      |Specified in G.709|
   |   |         |         |or lambda   |         |                  |
   |---+---------+---------+------------+---------+                  |
   |BW |X        |=bw      |=bw         |=bw      |                  |
   |   |         |         |or *<=bw    |         |                  |
   +---+---------+---------+------------+---------+------------------+

   If an interface supports only a specific bit-rate and format such as
   SONET/SDH or Ethernet encoding, BW X must be equal to bw so as to
   match bit-rate and its framing.

   * In the case of an interface with a lambda encoding and a
     transparent to bit-rate and framing, BW X must be equal to or less
     than bw.















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        Table 2.2: The Case of End-Point(Ingress/Egress) Link Attributes
                           with Lambda Encoding

   +-------------+---------+------------+---------+------------------+
   |LSP attribute|Ingress  |Transit     |Egress   |Remarks           |
   +---+---------+---------+------------+---------+------------------+
   |   |         |LSC      |            |LSC      |                  |
   |   |         +---------+            +---------+                  |
   |SC |LSC      |TDM      |LSC         |TDM      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |L2SC     |            |L2SC     |                  |
   |   |         +---------+            +---------+                  |
   |   |         |PSC      |            |PSC      |                  |
   +---+---------+---------+------------+---------+                  |
   |   |lambda   |         |lambda      |         |[RFC4202]         |
   |   +---------+         +------------+         |section 3.7, 3.10 |
   |Enc|SONET/SDH|         |SONET/SDH   |         |Specified in G.691|
   |   |         |         |or lambda   |         |                  |
   |   +---------+lambda   +------------+lambda   |                  |
   |   |Ethernet |         |Ethernet    |         |Specified in IEEE |
   |   |         |         |or lambda   |         |                  |
   |   +---------+         +------------+         |                  |
   |   |OTN      |         |OTN         |         |Specified in G.709|
   |   |         |         |or lambda   |         |                  |
   +---+---------+---------+------------+---------+                  |
   |BW |X        |<=bw     |=bw         |<=bw     |                  |
   |   |         |         |or *<=bw    |         |                  |
   +---+---------+---------+------------+---------+------------------+

   If an interface supports only a specific bit-rate and format such as
   SONET/SDH or Ethernet encoding, BW X must be equal to bw so as to
   match bit-rate and its framing.

   * In the case of an interface with a lambda encoding and a
     transparent to bit-rate and framing, BW X must be equal to or less
     than bw.















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           Table 2.3: The Case of One End-Point (Ingress/Egress) Link
                      Attribute with Lambda Encoding

   +-------------+---------+------------+---------+------------------+
   |LSP attribute|Ingress  |Transit     |Egress   |Remarks           |
   +---+---------+---------+------------+---------+------------------+
   |   |         |LSC      |            |LSC      |                  |
   |   |         +---------+            +---------+                  |
   |SC |LSC      |TDM      |LSC         |TDM      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |L2SC     |            |L2SC     |                  |
   |   |         +---------+            +---------+                  |
   |   |         |PSC      |            |PSC      |                  |
   +---+---------+---------+------------+---------+[RFC4202]         |
   |   |SONET/SDH|         |SONET/SDH   |SONET/SDH|section 3.6, 3.9  |
   |   |         |         |or lambda   |         |Specified in G.691|
   |   +---------+         +------------+---------+                  |
   |Enc|Ethernet |lambda   |Ethernet    |Ethernet |Specified in IEEE |
   |   |         |         |or lambda   |         |                  |
   |   +---------+         +------------+---------+                  |
   |   |OTN      |         |OTN         |OTN      |Specified in G.709|
   |   |         |         |or lambda   |         |                  |
   +---+---------+---------+------------+---------+                  |
   |BW |X        |<=bw     |=bw         |=bw      |                  |
   |   |         |         |or *<=bw    |         |                  |
   +---+---------+---------+------------+---------+------------------+

   The case of ingress link with the specific encoding and egress link
   with lambda encoding also follows the same manner.

   If an interface supports only a specific bit-rate and format such as
   SONET/SDH or Ethernet encoding, BW X must be equal to bw so as to
   match bit-rate and its framing.

   * In the case of an interface with a lambda encoding and a
     transparent to bit-rate and framing, BW X must be equal to or less
     than bw.














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3.3. Fiber Switch Capable (FSC)

     Table 3.1: The Case of End-Point(Ingress/Egress) Link Attributes
                     Without Lambda or Fiber Encoding

   +---+---------+---------+------------+---------+------------------+
   |LSP attribute|Ingress  |Transit     |Egress   |Remarks           |
   +---+---------+---------+------------+---------+------------------+
   |   |         |FSC      |            |FSC      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |LSC      |            |LSC      |                  |
   |   |         +---------+            +---------+                  |
   |SC |FSC      |TDM      |FSC         |TDM      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |L2SC     |            |L2SC     |                  |
   |   |         +---------+            +---------+                  |
   |   |         |PSC      |            |PSC      |                  |
   +---+---------+---------+------------+---------+[RFC4202]         |
   |Enc|SONET/SDH|SONET/SDH|SONET/SDH   |SONET/SDH|section 3.6, 3.9  |
   |   |         |         |or lambda   |         |Specified in G.691|
   |   |         |         |or fiber    |         |                  |
   |   +---------+---------+------------+---------+                  |
   |   |Ethernet |Ethernet |Ethernet    |Ethernet |Specified in IEEE |
   |   |         |         |or lambda   |         |                  |
   |   |         |         |or fiber    |         |                  |
   |   +---------+---------+------------+---------+                  |
   |   |OTN      |OTN      |OTN         |OTN      |Specified in G.709|
   |   |         |         |or lambda   |         |                  |
   |   |         |         |or fiber    |         |                  |
   +---+---------+---------+------------+---------+                  |
   |BW |X        |=bw      |=bw         |=bw      |                  |
   |   |         |         |or *<=bw    |         |                  |
   +---+---------+---------+------------+---------+------------------+

   If an interface supports only a specific bit-rate and format such as
   SONET/SDH or Ethernet encoding, BW X must be equal to bw so as to
   match bit-rate and its framing.

   * In the case of an interface with a lambda or fiber encoding and a
     transparent to bit-rate and framing, BW X must be equal to or less
     than bw.










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   Table 3.2: The Case of End-Point(Ingress/Egress) Link Attributes with
                         Lambda or Fiber Encoding

   +---+---------+---------+------------+---------+------------------+
   |LSP attribute|Ingress  |Transit     |Egress   |Remarks           |
   +---+---------+---------+------------+---------+------------------+
   |   |         |FSC      |            |FSC      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |LSC      |            |LSC      |                  |
   |   |         +---------+            +---------+                  |
   |SC |FSC      |TDM      |FSC         |TDM      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |L2SC     |            |L2SC     |                  |
   |   |         +---------+            +---------+                  |
   |   |         |PSC      |            |PSC      |                  |
   +---+---------+---------+------------+---------+[RFC4202]         |
   |   |fiber    |fiber    |fiber       |fiber    |section 3.8       |
   |   +---------+---------+------------+---------+                  |
   |Enc|lambda   |         |lambda      |         |section 3.7, 3.10 |
   |   |         |         |or fiber    |         |                  |
   |   +---------+         +------------+         |section 3.6, 3.9  |
   |   |SONET/SDH|         |SONET/SDH   |         |Specified in G.691|
   |   |         |         |or lambda   |         |                  |
   |   |         |lambda   |or fiber    |lambda   |                  |
   |   +---------+or fiber +------------+or fiber |                  |
   |   |Ethernet |         |Ethernet    |         |Specified in IEEE |
   |   |         |         |or lambda   |         |                  |
   |   |         |         |or fiber    |         |                  |
   |   +---------+         +------------+         |                  |
   |   |OTN      |         |OTN         |         |Specified in G.709|
   |   |         |         |or lambda   |         |                  |
   |   |         |         |or fiber    |         |                  |
   +---+---------+---------+------------+---------+                  |
   |BW |X        |<=bw     |=bw         |<=bw     |                  |
   |   |         |         |or *<=bw    |         |                  |
   +---+---------+---------+------------+---------+------------------+

   If an interface supports only a specific bit-rate and format such as
   SONET/SDH or Ethernet encoding, BW X must be equal to bw so as to
   match bit-rate and its framing.

   * In the case of an interface with a lambda or fiber encoding and a
     transparent to bit-rate and framing, BW X must be equal to or less
     than bw.







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   Table 3.3: The Case of One End-Point (Ingress/Egress) Link Attribute
                       with Lambda or Fiber Encoding

   +---+---------+---------+------------+---------+------------------+
   |LSP attribute|Ingress  |Transit     |Egress   |Remarks           |
   +---+---------+---------+------------+---------+------------------+
   |   |         |FSC      |            |FSC      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |LSC      |            |LSC      |                  |
   |   |         +---------+            +---------+                  |
   |SC |FSC      |TDM      |FSC         |TDM      |                  |
   |   |         +---------+            +---------+                  |
   |   |         |L2SC     |            |L2SC     |                  |
   |   |         +---------+            +---------+                  |
   |   |         |PSC      |            |PSC      |                  |
   +---+---------+---------+------------+---------+[RFC4202]         |
   |Enc|SONET/SDH|         |SONET/SDH   |SONET/SDH|section 3.6, 3.9  |
   |   |         |         |or lambda   |         |Specified in G.691|
   |   |         |         |or fiber    |         |                  |
   |   +---------+         +------------+---------+                  |
   |   |Ethernet |lambda   |Ethernet    |Ethernet |Specified in IEEE |
   |   |         |or fiber |or lambda   |         |                  |
   |   |         |         |or fiber    |         |                  |
   |   +---------+         +------------+---------+                  |
   |   |OTN      |         |OTN         |OTN      |Specified in G.709|
   |   |         |         |or lambda   |         |                  |
   |   |         |         |or fiber    |         |                  |
   +---+---------+---------+------------+---------+                  |
   |BW |X        |<=bw     |=bw         |=bw      |                  |
   |   |         |         |or *<=bw    |         |                  |
   +---+---------+---------+------------+---------+------------------+

   The case of ingress link with the specific encoding and egress link
   with lambda encoding also follows as the same manner.

   If an interface supports only a specific bit-rate and format such as
   SONET/SDH or Ethernet encoding, BW X must be equal to bw so as to
   match bit-rate and its framing.

   * In the case of an interface with a lambda encoding and a
     transparent to bit-rate and framing, BW X must be equal to or less
     than bw.

   Although the interface with FSC can switch the entire contents to
   another interface, this interface should only be used for optical
   wavelength or waveband switching.





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3.4. Layer 2 Switch Capable (L2SC)

   The guideline for the calculation must be created after the
   definition and discussion about L2SW are settled down.

3.5. Packet Switch Capable (PSC)

           Table 4: Desired GMPLS Attributes in the case of PSC
   +-------------+---------+------------+---------+------------------+
   |LSP attribute|Ingress  |Transit     |Egress   |Remarks           |
   +---+---------+---------+------------+---------+------------------+
   |SC |PSC      |PSC      |PSC         |PSC      |                  |
   +---+---------+---------+------------+---------+                  |
   |Enc|Packet   |Packet   |Packet      |Packet   |                  |
   +---+---------+---------+------------+---------+                  |
   |BW |X        |<=bw     |<=bw        |<=bw     |                  |
   +---+---------+---------+------------+---------+------------------+


   Since the interface with PSC supports only packet-by-packet
   switching, BW X must be equal to or less than bw, and must be larger
   than the minimum LSP bandwidth.

   These GMPLS constraints must be considered for computing paths and
   creating GMPLS LSPs.

   This document does not discuss domain based multilayer path
   computation considerations where specific routing policies, which are
   sometimes independent from the underlying domains and sometimes take
   the underlying domains' policies into consideration, are required.

4. Security Consideration

   Anything that can be done to change the output of a path computation
   algorithm can significantly affect the operational stability of a
   network, could force traffic to traverse undesirable or costly links,
   and could place data into less secure parts of the network.
   Therefore, the integrity of the path computation mechanism is very
   significant in a GMPLS network.

   The path computation algorithm, itself, and the mechanisms for
   conveying computed paths to and between the LSRs in the network are
   out of scope for this document. But misuse or confusion with respect
   of the handling of the attributes described in this document could
   leave a network open to various security attacks. In particular, if
   there is a known mismatch between the interpretation or handling of
   TE attributes within a network this might be exploited by an attacker
   to cause disruption or to waste network resources in an integrated
   multi-technology network. Therefore, network operators are
   RECOMMENDED to use a consistent approach across the whole network.

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5. IANA Considerations

   This informational document makes no requests for IANA action.

6. Acknowledgements

   Thanks to Adrian Farrel for his review of this document.

7. Intellectual Property Considerations

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in BCP 78 and BCP 79.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   http://www.ietf.org/ipr.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at
   ietf-ipr@ietf.org.

8. References

8.1 Normative References

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

  [RFC4202] Kompella, K., and Rekhter, Y., "Routing Extensions in
            Support of Generalized Multi-Protocol Label Switching",
            RFC4202, October 2005.

  [RFC4203] Kompella, K., and Rekhter, Y., "OSPF Extensions in
            Support of Generalized Multi-Protocol Label Switching",
            RFC4203, October 2005.





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8.2 Informative References

  [RFC3477] Kompella, K., and Rekhter, Y., "Signalling Unnumbered
            Links in Resource ReSerVation Protocol - Traffic Engineering
            (RSVP-TE)", RFC3477, January 2003.

  [RFC3630] Katz, D., et al., "Traffic Engineering (TE) Extensions to
            OSPF Version 2", RFC3630, September 2003.

  [RFC3945] Mannie, E., et al., "Generalized Multi-Protocol Label
            Switching Architecture", RFC3945, October, 2004.

Authors' Addresses

   Tomohiro Otani
   KDDI R&D Laboratories, Inc.
   2-1-15 Ohara Fujimino-shi
   Saitama, 356-8502 Japan
   Phone: +81-49-278-7357
   Email: otani@kddilabs.jp

   Kenichi Ogaki
   KDDI R&D Laboratories, Inc.
   2-1-15 Ohara Fujimino-shi
   Saitama, 356-8502 Japan
   Phone: +81-49-278-7897
   Email: ogaki@kddilabs.jp

   Arthi Ayyangar
   Nuova Systems
   2600 San Tomas Expressway
   Santa Clara, CA  95051
   Email: arthi@nuovasystems.com

   Rajiv Papneja
   Isocore
   12359 Sunrise Valley Drive
   Suite 100, Reston, VA 20191 US
   Email: rpapneja@isocore.com

   Kireeti Kompella
   Juniper Networks
   1194 N. Mathilda Ave.
   Sunnyvale, CA 94089 US
   Email: kireeti@juniper.net

   Daniel King
   Aria Networks Ltd.
   Email: daniel.king@aria-networks.com


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Document Expiration

   This document will be expired in September 2007, unless it is
   updated.

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