One document matched: draft-shiomoto-ccamp-lsp-hierarchy-bis-00.txt







      
      
     Network Working Group                                  K. Shiomoto(NTT)  
     Internet Draft                                       R. Rabbat(Fujitsu) 
     Updates: MPLS-HIER, 3477                 A. Ayyangaer(Juniper Networks) 
     Proposed Category: Proposed Standard       A. Farrel(Old Dog Consulting) 
                                                   
     Expires: April 2006                                    October 17, 2005 
                                         
      
                                           
            Advertisement of hierarchical and stitchable LSPs as TE Links  
                    draft-shiomoto-ccamp-lsp-hierarchy-bis-00.txt 


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     Copyright Notice 

        Copyright (C) The Internet Society (2005).  All Rights Reserved. 





      
      
      
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     Abstract  

        This document addresses topics related to hierarchical and stitched 
        Label Switched Paths (LSPs).  It describes extensions to allow an 
        egress to identify that an LSP will be used as a dynamically signaled 
        Forwarding Adjacency LSP (FA-LSP) in the case of numbered FA's.  In 
        addition, the document addresses the issue of how to indicate that an 
        LSP should be advertised as a TE link into a different instance of 
        the control plane and how to identify the instance that should be 
        used.   

     Conventions used in this document 

        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]. 

     Table of Contents 

        1. Introduction and Problem Statement.............................3 
           1.1. LSP Hierarchy.............................................3 
           1.2. Problem Statement.........................................3 
           1.3. Current Approaches and Shortcomings.......................5 
           1.4. Contents of This Document.................................5 
        2. Proposed Solution..............................................6 
           2.1. Control Plane Instance Identification.....................6 
           2.2. LSP_TUNNEL_INTERFACE_ID Object............................7 
              2.2.1. Unnumbered link......................................7 
              2.2.2. IPv4 numbered link...................................8 
              2.2.3. IPv6 numbered link...................................9 
              2.2.4. Unnumbered link with target control plane instance 
              identifier..................................................9 
           2.3. TLVs.....................................................10 
           2.4. LSA advertisement........................................10 
        3. Applicability Statement.......................................11 
        4. Backward Compatibility Considerations.........................11 
        5. Security Considerations.......................................12 
        6. IANA Considerations...........................................12 
        7. References....................................................12 
           7.1. Normative References.....................................12 
           7.2. Informative References...................................13 
        Author's Addresses...............................................13 
        Intellectual Property Statement..................................14 
        Disclaimer of Validity...........................................14 
        Copyright Statement..............................................15 
        Acknowledgment...................................................15 

      
      
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     1. Introduction and Problem Statement 

     1.1. LSP Hierarchy 

        LSP hierarchy has been developed to improve the scalability of 
        Generalized Multi-Protocol Label Switching (GMPLS) by aggregating 
        LSPs into a hierarchy of such LSPs [HIERAR]. 

        The operation is as follows for a numbered Forwarding Adjacency:  

        1. The ingress signals the LSP using a /31 sender address that it 
           allocates. 

        2. The egress sets up the LSP. 

        3. The ingress then forms a Forwarding Adjacency (FA) out of that LSP 
           by advertising it as a Traffic Engineering (TE) link; toward that 
           end, it uses the routing protocol (OSPF/ISIS) to advertise the TE 
           link using the /31 address.  The head-end address of the FA-LSP is 
           specified in the IPv4 tunnel sender address in the Sender Template 
           Object of the FA LSP. 

        4. When the egress receives the advertised TE link information, it 
           checks the Link-ID address of the TE advertisement against its own 
           TE Router ID.  If it matches its own TE Router ID, the egress 
           checks the advertising router ID of the TE advertisement against 
           the ingress addresses of LSPs for which it is the egress and finds 
           the address match with the advertising router ID of the TE 
           advertisement. 

        5. The egress then advertises the TE information setting the 
           advertising TE Router ID in the Link-ID and the assigned /31 
           address in the local interface address.  

        Nesting of LSPs originated by other LSRs into that LSP can be 
        achieved by using the label stack construct. 

     1.2. Problem Statement 

        The extensions described in this document are intended for 
        dynamically signaled bi-directional Forwarding Adjacency LSP (FA-LSP). 

        In order that the egress of an LSP can advertise the LSP as a TE link 
        it needs to know that such an advertisement is desirable, and it also 
        needs to know the TE Router ID of the ingress LSR (Please recall that 

      
      
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        the Router ID of the other end of the link is set in the Link-ID sub-
        TLV of the Link TLV of TE Opaque-LSA [RFC3630]).  For the numbered FA, 
        there is no place in the RSVP signaling messages of FA LSP to carry 
        the TE Router ID of the ingress LSR.  Therefore the egress LSR has to 
        wait to receive the TE advertisement by the ingress LSR to learn the 
        TE Router ID of the ingress node until it advertises the FA as 
        described in Section 1.2. 

        Different methods for the exchange of both numbered and unnumbered 
        endpoints are defined in [HIERAR] and [RFC3477] respectively.  For 
        unnumbered TE links this information is available using the 
        mechanisms in [RFC3477].  If the LSP_TUNNEL_INTERFACE_ID object is 
        present, it indicates that the LSP is to be advertised as a TE link, 
        and it contains the TE Router ID of the ingress LSR.  However, for 
        numbered TE links, the mechanism in [HIERAR] does not provide this 
        information.  Since the LSP_TUNNEL_INTERFACE_ID object is not used 
        there is no trigger for TE link advertisement on the egress.  

        Related to the above problem, a few key observations are worth 
        noting: 

        1. The concept of an FA is applicable only when an LSP is both 
           created and used as a TE link by exactly the same instance of the 
           GMPLS control plane.  [HIERAR] did not consider scenarios where an 
           LSP is created (and maintained) by one instance of the GMPLS 
           control plane, and is used as a (TE) link by another instance of 
           the GMPLS control plane.  This leaves open the question of 
           advertising a TE link into a different instance of the control 
           plane as is needed in multi-region/multi-layer networks [MRN].  
           [HIERAR] also does not address how to identify which instance of 
           the control plane should be used. 

        2. [HIERAR] provides a way to exchange numbered identifiers for the 
           TE link, but this does not serve as a trigger for TE link 
           advertisement. 

        3. It is important to note that an LSP that is set up in a GMPLS 
           transport network then advertised as a TE link in the MPLS data 
           network is NOT an FA-LSP.   








      
      
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        4. When an egress checks the address of the advertised TE link to 
           find the LSP sender (Recall step (4) as described in section 1.1), 
           it must check the Link-ID address of all received TE 
           advertisements against its own TE Router ID.  If it matches its 
           own TE Router ID, the egress checks the advertising router ID of 
           the TE advertisement against the ingress addresses of all LSPs for 
           which it is the egress.  It is an assertion of the authors that 
           this method is not scalable due to the amount of processing needed 
           for all the TE Link State Advertisements (LSAs). 

     1.3. Current Approaches and Shortcomings 

        [RFC3477] provides a mechanism to exchange unnumbered identifiers for 
        the TE link during H-LSP establishment, and this can be used as a 
        notification to the egress that the LSP will be used as a TE link. 

        So for unnumbered TE links, there is a well-defined trigger available.  
        The use of unnumbered TE links may be arguably more sensible, 
        especially in the case of large networks.  Some operators though 
        prefer to consistently use numbered TE links for both static and 
        dynamic TE links in their networks. In case of numbered TE links, 
        however, there is no such available trigger for the egress to know 
        that an H-LSP should be advertised as a TE link. 

        In addition, using unnumbered TE links still does not address the 
        issue of advertising TE links into different layers, nor is it 
        sufficient for dynamic bundling. 

        The Link Management Protocol (LMP) [LMP] could possibly be run on 
        remote adjacencies between the endpoints of the LSP.  LMP peer 
        discovery is required for dynamic LMP peering.  In addition, remote 
        LMP adjacency remains unproven.  Last, it would require that all 
        layers/regions in an MRN network to run LMP.  This may not be the 
        case and would put undue burden on the network operator to deploy 
        fully a new protocol. 

     1.4. Contents of This Document 

        This document provides a consolidated way of exchanging TE link 
        identifiers when an LSP is established through signaling. It also 
        provides a mechanism to allow the ingress to control whether, and 
        into which control plane instances, an LSP is advertised as a TE link 
        by the egress. The proposed mechanism applies equally to Hierarchical 
        LSPs (H-LSPs) and Stitchable LSPs (S-LSPs).   



      
      
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        The method described below extends the method described in [RFC3477], 
        which is applied for an unnumbered TE link represented as an FA. 

     2. Proposed Solution 

        The following method allows the ingress and egress LSR to exchange 
        the link address or link identifier (including the node ID) of the 
        other end of a TE link for numbered and unnumbered TE link.  It is an 
        extension of the procedures defined in [RFC3477] for unnumbered TE 
        links. 

        If a head-end LSR that originates an LSP intends to advertise this 
        LSP as a TE link in IS-IS or OSPF [LSP-HIER], the head-end LSR MUST 
        allocate an address or identifier to the TE link (just like for any 
        other TE link).  Moreover, the Path message used for establishing the 
        LSP that will be used to form the TE link MUST contain the 
        LSP_TUNNEL_INTERFACE_ID object (as extended and described below), 
        with the interface address or identifier allocated by the head-end 
        LSR. 

        If the Path message for the H-LSP/S-LSP contains the 
        LSP_TUNNEL_INTERFACE_ID object, then the tail-end LSR MUST allocate 
        an address or identifier to that TE link (just like for any other 
        numbered or unnumbered TE link).  Furthermore, the Resv message for 
        the LSP MUST contain an LSP_TUNNEL_INTERFACE_ID object, with the 
        interface address or identifier allocated by the tail-end LSR 

        In all cases where an LSP is to be advertised as a TE link the Tunnel 
        Sender Address in the Sender Template Object MUST be set to the TE 
        Router ID of the head-end LSR. We should note that this is a change 
        from the method described in [HIER].  

        Once the addresses or identifiers for the LSP have been exchanged 
        using these signaling extensions, and once the LSP has been 
        successfully established the head-end and tail end SHOULD advertise 
        the LSP as a TE link using the addresses/identifiers exchanged.  Once 
        the TE link advertisement has been flooded it is available for use in 
        path computation and LSP signaling just like any other TE link. 

     2.1. Control Plane Instance Identification 

        The mechanism described so far allows a head-end LSR to indicate that 
        an LSP is to be used as a TE link and allows the head-end and tail-
        end LSRs to exchange addresses or identifiers for that TE link, 
        during LSP setup. 


      
      
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        However, it is also necessary to indicate into which instance of the 
        control plane the advertisement should be made.  This first requires 
        that a 32-bit identifier is assigned to each of the various control 
        plane instances within a network, and that head-end and tail-end LSRs 
        have the same understanding of these numbers.  This is a management 
        configuration exercise outside the scope of this document. 

        Once these numbers have been assigned, they MAY be signaled as 
        additional information in the LSP_TUNNEL_INTERFACE_ID object to 
        indicate to which instance of the control plane the object applies.   

        The control plane instance identifier value of zero is reserved to 
        mean indicate that the TE link SHOULD be advertised into the same 
        instance of the control plane as was used to establish the LSP.  That 
        is, a value of zero means that an FA is to be established. 

     2.2. LSP_TUNNEL_INTERFACE_ID Object 

        The LSP_TUNNEL_INTERFACE_ID object defined in [RFC3477] has a class 
        number of 193,  which designates that a node that does not understand 
        the object SHOULD ignore the object but forward it, unexamined and 
        unmodified, in all messages resulting from this message. 

        [RFC3477] defines one class type to indicate an unnumbered interface 
        identifier.  This document defines three new class types as follows. 

        C-Type               Meaning                                Reference 
        --------------------------------------------------------------------- 
         1                  Unnumbered interface identifier        [RFC3477] 
         2 (TBD by IANA)    IPv4 interface identifier with target      2.3.2 
         3 (TBD by IANA)    IPv6 interface identifier with target      2.3.3 
         4 (TBD by IANA)    Unnumbered interface with target           2.3.4 
           
        Multiple instances of the LSP_TUNNEL_INTERFACE_ID object with C-Type 
        values 2, 3 or 4 MAY appear in any one Path or Resv message, in which 
        case, each MUST have a different value for the Target Control Plane 
        Instance field.  A Path or Resv message MUST NOT contain more than 
        one instance of the LSP_TUNNEL_INTERFACE_ID object with C-Type 1, and 
        if such an object is present, other instances of the object with any 
        other C-Type value MUST NOT have Target Control Plane Instance set to 
        zero. 

     2.2.1. Unnumbered link 

        The unnumbered link identifier defined by [RFC3477] is not changed by 
        this document.  Its usage also remains the same.  That is, when 

      
      
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        present in a Path message it indicates that the LSP being established 
        SHOULD be advertised by the egress LSR as a TE link, and that 
        unnumbered link identifier is the ingresses identifier for the TE 
        link. 

        Note that since this form of the object does not contain a target 
        instance identifier it cannot identify a specific instance of the 
        control plane into which this TE link should be advertised.  Thus, 
        when C-Type 1 is used, the TE link SHOULD be advertised only into the 
        same instance of the control plane as was used to create the LSP.  
        That is, the use of C-Type 1 is unchanged from [RFC3477] and is used 
        to create an unnumbered Forwarding Adjacency. 

        This object can optionally appear in either a Path message or a Resv 
        message.  In the former case, we call it the "Forward Interface ID" 
        for that LSP; in the latter case, we call it the "Reverse Interface 
        ID" for the LSP. 

        Only one instance of this object with C-Type 1 may be present on a 
        Path or Resv message. 

     2.2.2. IPv4 numbered link 

        A new C-Type variant of the LSP_TUNNEL_INTERFACE_ID Object is defined 
        to carry an IPv4 numbered interface address and to indicate into 
        which instance of the control plane the consequent TE link should be 
        advertised. 

        The format of the object is as shown below. 

         

        C-NUM = 193, C-Type = 2(TBD by IANA) 
            0                   1                   2                   3 
            0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |               IPv4 Interface Address (32 bits)                | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |               Target Control Plane Instance (32 bits)         | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |                           TLVs                                | 
           ~                                                               ~ 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
         



      
      
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        This object can optionally appear in either a Path message or a Resv 
        message.  In the former case, we call it the "Forward Interface 
        Address" for that LSP; in the latter case, we call it the "Reverse 
        Interface Address" for the LSP. 

     2.2.3. IPv6 numbered link 

        A new C-Type variant of the LSP_TUNNEL_INTERFACE_ID Object is defined 
        to carry an IPv6 numbered interface address and to indicate into 
        which instance of the control plane the consequent TE link should be 
        advertised. 

        The format of the object is as shown below. 

        C-NUM = 193, C-Type = 3(TBD by IANA) 
            0                   1                   2                   3 
            0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |               IPv6 Interface Address (128 bits)               | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |               IPv6 Interface Address (128 bits)               | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |               IPv6 Interface Address (128 bits)               | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |               IPv6 Interface Address (128 bits)               | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |               Target Control Plane Instance (32 bits)         | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |                           TLVs                                | 
           ~                                                               ~ 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
         

        This object can optionally appear in either a Path message or a Resv 
        message.  In the former case, we call it the "Forward Interface 
        Address" for that LSP; in the latter case, we call it the "Reverse 
        Interface Address" for the LSP. 

     2.2.4. Unnumbered link with target control plane instance identifier 

        A new C-Type variant of the LSP_TUNNEL_INTERFACE_ID Object is defined 
        to carry an unnumbered interface identifier and to indicate into 
        which instance of the control plane the consequent TE link should be 
        advertised.  This does not deprecate the use of C-Type 1, but extends 
        its utility. 


      
      
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        The format of the object is as shown below. 

        C-NUM = 193, C-Type = 4(TBD by IANA) 
            0                   1                   2                   3 
            0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |                        LSR's Router ID                        | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |                    Interface ID (32 bits)                     | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |               Target Control Plane Instance (32 bits)         | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |                           TLVs                                | 
           ~                                                               ~ 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
                           

        This object can optionally appear in either a Path message or a Resv 
        message.  In the former case, we call it the "Forward Interface ID" 
        for that LSP; in the latter case, we call it the "Reverse Interface 
        ID" for the LSP. 

     2.3. TLVs 

        All TLVs of the LSP_TUNNEL_INTERFACE_ID object have the following 
        format. 

            0                   1                   2                   3 
            0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |         Type (16 bits)        |       Length (16 bits)        | 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
           |                        Value (variable)                       | 
           ~                                                               ~ 
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
         

        The length field contains the total length of the TLV including the 
        Type and Length fields in bytes. A value field whose length is not a 
        multiple of four MUST be zero-padded so that the TLV is four-byte 
        aligned. 

     2.4. LSA advertisement 

        The ingress and egress LSRs MAY advertise link state associated with 
        TE links created as described above.  The link state may be 

      
      
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        advertised in either the same control plane instance as used to 
        compute and signal the path for the LSPs that support the TE links, 
        or another control plane instance.  In the former case, the address 
        space for the link state MUST be the same as that used to establish 
        the LSPs.  In the latter case, the address space for the link state 
        MAY be different, which means that addresses already allocated in the 
        control plane instance used to establish the LSPs MAY be used by the 
        advertised TE link without any ambiguity. 

        In the routing protocol the TE Router ID of the ingress LSR is taken 
        from the Tunnel Sender Address in the Sender Template object.  It is 
        assumed that the ingress LSR knows the TE Router ID of the egress LSR 
        since it has chosen to establish an LSP to that LSR and plans to use 
        the LSP as a TE link. 

        The link interface addresses or link interface identifiers for the 
        forward and reverse direction links are taken from the 
        LSP_TUNNEL_INTREFACE_ID object on the Path and Resv messages 
        respectively. 

        Address overlap checking for these objects MUST be turned off in case 
        that the LSA is advertised into a control plane instance different 
        from the one used to establish the LSP because the addresses MAY be 
        allocated in both domains. 

     3. Applicability Statement 

        The method is applicable for both hierarchical LSP [HIERAR] and LSP 
        stitching [STITCH]. 

        The method is applicable for bundled links. 

     4. Backward Compatibility Considerations 

        The method does not impact the method to exchange unnumbered FA 
        information described in [RFC3477].  This mechanism can be safely 
        used in combination with the new mechanisms described here and is 
        functionally equivalent to using the new C-Type indicating an 
        unnumbered link with target control plane instance identifier with 
        the Target Control Plane Instance value set to zero. 

        The method obsoletes the method to exchange the numbered FA 
        information described in [HIERAR].  This is not believed to be an 
        issue as an informal survey indicated that dynamically signalled 
        numbered FAs had not been deployed.  Indeed it was the attempt to 
        implement numbered FAs that gave rise to the work on this document. 

      
      
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     5. Security Considerations 

        [RFC3477] points out that one can argue that the use of the extra    
        interface identify that it provides could make an RSVP message harder 
        to spoof.  In that respect, the minor extensions to the protocol made 
        in this document do not constitute an additional security risk, but 
        could also be said to improve security. 

        It should be noted that the ability of an ingress LSR to request that 
        an egress LSR advertise an LSP as a TE link MUST be subject to 
        appropriate policy checks at the egress LSR.  That is, the egress LSR 
        MUST NOT automatically accept the word of the ingress unless it is 
        configured with such a policy. 

     6. IANA Considerations 

        This document defines three new C-Types for the 
        LSP_TUNNEL_INTERFACE_ID object.  The C-Types for this object are 
        managed by IANA, and IANA is requested to assign values to the new C-
        Types as tabulated in section 2.3 and described in sections 2.3.2, 
        2.3.3 and 2.3.4. 

     7. Acknowledgement 

        The authors would like to thank John Drake for valuable discussiond 
        and comments. 

         

     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. 

        [RFC3477] Kompella, K. and Y. Rekhter, "Signalling Unnumbered Links 
                  in Resource ReSerVation Protocol - Traffic Engineering 
                  (RSVP-TE)", RFC 3477, January 2003. 

         [HIERAR]   Kompella, K. and Y. Rekhter, "LSP Hierarchy with 
                  Generalized MPLS TE", draft-ietf-mpls-lsp-hierarchy-08 
                  (work in progress), September 2002. 




      
      
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        [STITCH]  Ayyangar, A. and J.P. Vasseur, "Label Switched Path 
                  Stitching with Generalized MPLS Traffic Engineering", 
                  draft-ietf-ccamp-lsp-stitching-01, (work in progress),  
                  July 2005. 

     8.2. Informative References 

        [LMP]     Lang, J. (Ed.), "Link Management Protocol (LMP)",     
                  draft-ietf-ccamp-lmp-10, (work in progress), October 2003. 

        [MRN]     Shiomoto, K., et al, " Requirements for GMPLS-based multi-
                  region and multi-layer networks (MRN/MLN)", draft-shiomoto-
                  ccamp-gmpls-mrn-reqs-02, (work in progress), July 2005. 

     Author's Addresses 

         

        Kohei Shiomoto 
        NTT Network Service Systems Laboratories 
        3-9-11 Midori 
        Musashino, Tokyo 180-8585 
        Japan 
        Phone: +81 422 59 4402 
        Email: shiomoto.kohei@lab.ntt.co.jp 
         

        Richard Rabbat 
        Fujitsu Laboratories of America 
        1240 East Arques Ave, MS 345 
        Sunnyvale, CA 94085 
        United States of America 
        Phone: +1 408-530-4537 
        Email: richard@us.fujitsu.com 
         












      
      
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        Arthi Ayyangar 
        Juniper Networks 
        1194 N. Mathilda Ave. 
        Sunnyvale, CA  94089 
        United States of America 
        Phone:  
        Email: arthi@juniper.net  
         
        Adrian Farrel 
        Old Dog Consulting 
        EMail: adrian@olddog.co.uk 
         
         

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PAFTECH AB 2003-20262026-04-23 12:36:09