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      IS-IS Working Group                                    JP Vasseur (Ed.)
                                                             Cisco System Inc.
      Internet Draft                                         JL Le Roux (Ed.)
                                                                France Telecom
                                                              Stefano Previdi
                                                                 Cisco Systems
                                                                   Paul Mabey
                                                                         Qwest
      
      
      Category: Standard Track
      Expires: January 2005                                          July 2004
      
      
                    IS-IS MPLS Traffic Engineering capabilities
      
                     draft-vasseur-isis-te-caps-00.txt
      
      
      Status of this Memo
      
         By submitting this Internet-Draft, I certify that any applicable
         patent or other IPR claims of which I am aware have been disclosed,
         and any of which I become aware will be disclosed, in accordance with
         RFC 3668.
      
         This document is an Internet-Draft and is in full conformance with
         all provisions of Section 10 of RFC2026. Internet-Drafts are working
         documents of the Internet Engineering Task Force (IETF), its areas,
         and its working groups. Note that other groups may also distribute
         working documents as Internet-Drafts.
      
         Internet-Drafts are draft documents valid for a maximum of six months
         and may be updated, replaced, or obsoleted by other documents at any
         time. It is inappropriate to use Internet- Drafts as reference
         material or to cite them other than as "work in progress."
      
         The list of current Internet-Drafts can be accessed at
         http://www.ietf.org/ietf/1id-abstracts.txt.
      
         The list of Internet-Draft Shadow Directories can be accessed at
         http://www.ietf.org/shadow.html.
      
      Abstract
      
         This document specifies IS-IS traffic engineering capability sub-TLVs
         related to various router MPLS Traffic Engineering capabilities.
         These sub-TLVs are carried within the IS-IS CAPABILITY TLV.
      
      
      
      
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      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 RFC-2119.
      
      Table of Contents
      
         1. Terminology.....................................................2
         2. Introduction....................................................3
         3. TE Node Capability Descriptor sub-TLV format....................3
         3.1. The DATA-PLANE-CAPABILITY sub-TLV.............................4
         3.2. The CONTROL-PLANE-CAPABILITY sub-TLV..........................4
         4. PCED sub-TLV format.............................................5
         4.1. PCE-ADDRESS sub-TLV...........................................5
         4.2. PCE-CAPABILITY sub-TLV........................................6
         4.3. AS-DOMAIN sub-TLV.............................................7
         5. TE-Mesh-Group sub-TLV format....................................8
         6. Element of procedure............................................8
         6.1. TE-NODE-CAP sub-TLV...........................................9
         6.2. PCED sub-TLV..................................................9
         6.3. TE-MESH-GROUP sub-TLV........................................11
         7. Interoperability with routers not supporting the IS-IS MPLS TE
         capabilities......................................................12
         8. Security considerations........................................12
         9. Intellectual Property Statement................................12
         10. References....................................................12
         11. Authors' Address:.............................................13
      
      
      1. Terminology
      
         Terminology used in this document
      
            LSR: Label Switch Router.
      
            PCE: Path Computation Element whose function is to compute the
                 path of a TE LSP it is not the head-end for. The PCE may be
                 an LSR or an offline tool not forwarding packet.
      
            PCC: Path Computation Client (any head-end LSR) requesting a TE
                 LSP path computation to the Path Computation Element.
      
            TE LSP: Traffic Engineering Label Switched Path.
      
            TE LSP head-end: head/source of the TE LSP.
      
            TE LSP tail-end: tail/destination of the TE LSP.
      
            Intra-area TE LSP: TE LSP whose path does not transit across
            areas.
      
      
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            Inter-area TE LSP: A TE LSP whose path transits across at least
            two different IGP areas.
      
            Inter-AS MPLS TE LSP: A TE LSP whose path transits across at least
            two different ASes or sub-ASes (BGP confederations).
      
      2. Introduction
      
         This document defines IS-IS protocol extensions and procedures for
         the advertisement TE node capabilities. The functional description of
         these extensions is defined in [TE-INFO], and is not repeated here.
      
         This document describes the usage of several IS-IS TE capabilities
         sub-TLVs: the PCED (PCE Discovery), the TE-MESH-GROUP and the TE-
         NODE-CAP sub-TLVs. These IS-IS TE capability sub-TLVs are carried
         within the IS-IS CAPABILITY TLV specified in [IS-IS-CAP].
      
         Each sub-TLV defined in this document is composed of 1 octet for the
         type, 1 octet specifying the TLV length and a value field.
      
         The format of each sub-TLV is identical to the TLV format used by the
         Traffic Engineering Extensions to IS-IS [IS-IS-TE].
      
         The TE-NODE-CAP sub-TLV is used for the advertisement of both
         control plane and data plane TE node capabilities. The TE-NODE-CAP
         sub-TLV is made of a set of non-ordered sub-TLVs each having the
         format as described above.
      
         The PCED sub-TLV is used for the advertisement of Path
         Computation Element capabilities. The PCED sub-TLV is made of a set
         of non-ordered sub-TLVs each having the format as described above.
      
         The TE-MESH-GROUP sub-TLV is used to advertise the desire to
         join/leave a given MPLS-TE mesh group. The TE-MESH-GROUP sub-TLV does
         not have any sub-TLV currently defined.
      
      3. TE Node Capability Descriptor sub-TLV format
      
         This section specifies the sub-TLVs carried within the TE-NODE-CAP
         sub-TLV payload which define the TE node capabilities.
      
         The TE-NODE-CAP sub-TLV type is 1.
      
         The TE-NODE-CAP sub-TLV is made of various non ordered sub-TLVs.
         Currently two sub-TLVs are defined.
      
            TLV type  Length               Name
               1      variable     DATA-PLANE-CAPABILITY sub-TLV
               2      variable     CONTROL-PLANE-CAPABILITY sub-TLV
      
         Any non recognized sub-TLV MUST be silently ignored.
      
      
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         More sub-TLV could be added in the future to handle new capabilities.
      
         3.1. The DATA-PLANE-CAPABILITY sub-TLV
      
         The DATA-PLANE-CAPABILITY is a series of bit flags and has a variable
         length.
      
            CODE: 1
            LENGTH: Variable (N*8)
      
      
             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
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |B|E|                                                           |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           //                                                               //
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      
                                    TE-NODE-CAP sub-TLV format
      
      
         Two bits are currently defined:
      
         -B bit: When set this indicates that the LSR can act as a branch node
         on a P2MP LSP.
      
         -E bit: When set, this indicates that the LSR can act as a bud LSR on
         a P2MP LSP, i.e. and LSR that is both transit and egress.
      
         See [P2MP-REQ]) and [RSVP-P2MP] for more details on the usage of
         these bits.
      
         Note that more flags may be defined in the future.
      
         3.2. The CONTROL-PLANE-CAPABILITY sub-TLV
      
         The CONTROL-PLANE-CAPABILITY is a series of bit flags and has a
         variable length.
      
            CODE: 2
            LENGTH: Variable (N*8)
      
      
             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
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |M|G|P|                                                          |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           //                                                               //
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      
                                    TE-NODE-CAP sub-TLV format
      
      
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         Currently three flags are defined:
      
         -M bit: If set this indicates that the LSR supports MPLS-TE
         signalling ([RSVP-TE]).
      
         -G bit: If set this indicates that the LSR supports GMPLS signalling
         ([RSVP-G]).
      
         -P bit: If set this indicates that the LSR supports P2MP MPLS-TE
         signalling ([RSVP-P2MP]).
      
         Note that more flags may be defined in the future.
      
      4. PCED sub-TLV format
      
         This section specifies the sub-TLVs carried within the PCED sub-TLV
         payload which describes the PCE capabilities.
      
         The PCED sub-TLV type is 2.
      
         The PCED sub-TLV is made of various non ordered sub-TLVs defined
         below:
      
            TLV type  Length               Name
               1      variable     PCE-ADDRESS sub-TLV
               2        8          PCE-CAPABILITY sub-TLV
               3        8          AS-DOMAIN sub-TLV
      
         Any non recognized sub-TLV MUST be silently ignored and unchanged.
      
         4.1. PCE-ADDRESS sub-TLV
      
         The PCE-ADDRESS sub-TLV specifies the IP address to be used to  reach
         the PCE described by this PCED sub-TLV. This address will typically
         be a loop-back address that is always reachable, provided the router
         is not isolated. The PCE-ADDRESS sub-TLV is mandatory.
      
         PCE-ADDRESS sub-TLV type is 1, length is 4 octets for an IPv4
         address and 20 octets for an IPv6 address, and the value is the PCE
         IPv4 or IPv6 address.
      
            CODE: 1
            LENGTH: Variable (4 or 20)
      
      
              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
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             |     address-type              |          Reserved             |
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
             |                                                               |
             //                       PCE IP address                        //
             |                                                               |
      
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             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      
                                  PCE-ADDRESS sub-TLV format
      
            Address-type:
               1   IPv4
               2   IPv6
      
         The PCE-ADDRESS sub-TLV MUST appear exactly once in the PCED sub-TLV
         originated by a router. The only exception is when the PCE has both
         an IPv4 and IPv6 address; in this case, two Path Computation Element
         address sub-TLVs might be inserted: one for the IPv4 address, one for
         the IPv6 address, in this order.
      
         4.2. PCE-CAPABILITY sub-TLV
      
         The PCE-CAPABILITY sub-TLV is used by the PCE to signal its Path
         Computation Element capabilities. This could then be used by an LSR
         to select the appropriate PCE among a list of PCE candidates. This
         sub-TLV is optional.
      
         The PCE-CAPABILITY sub-TLV type is 2 and the length is 8 octets.
      
            CODE: 2
            LENGTH: 4
      
      
          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
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                       Reserved                    |D|M|P|A|I|L|
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      
                                 PCE-CAPABILITY sub-TLV format
      
         The first 3 bits L, I and A defines the PCE scope for which the
         Path Computation Element is capable of performing the TE LSP path
         computation.
      
         L bit:
         Local scope. When set, this flag indicates that the PCE can compute
         paths for the IS-IS level the ISIS CAPABILITY TLV is flooded into
         (the PCE can compute TE LSP paths for intra-area TE LSPs).
      
         I bit:
         Inter-area scope. When set, the PCE can perform TE LSP path
         computation for inter-area TE LSPs but within the same AS.
      
         A bit:
         Multi-domain scope. When set, the PCE can perform path computation
         for inter-AS TE LSPs. In this case, the PCED sub-TLV MUST contain one
         or more AS-DOMAIN sub-TLV(s), each describing the domain for which
         the PCE can compute TE LSPs paths having their destination address in
      
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         the respective AS.
      
         Note that those flags are not exclusive (a PCE may set one or more
         flags).
      
         P bit:
         The notion of request priority allows a PCC to specify how urgent the
         request is, by setting a flag in the REQUEST_ID object of the Path
         computation request message. See [PATH-COMP] for more details.
      
         P=1: the PCE takes into account the ¬¬request priority¬¬ in its
         scheduling of the various requests.
         P=0: the PCE does not take the request priority into account.
      
         M bit
         M=1: the PCE is capable of computing more than one path obeying a set
         of specified constraints (in a single pass), provided that they
         exist.
         M=0: the PCE cannot compute more than one path in a single pass
         obeying a set of specified constraints.
      
         D bit
         The PCC may request the PCE to compute N diversely routed paths
         obeying a set of specified constraints. Such N paths may not exist of
         course depending on the current state of the network. S
         D=1: the PCE is capable of computing diversely (link, node, SRLG)
               routed paths.
         D=0: the PCE is not capable of computing diversely routed paths.
         The D bit is relevant if and only if the M bit has been set to 1. It
         MUST be set to 0 if the M bit is set to 0.
      
         Note that for future capabilities, it may be desirable to introduce
         new flags or may be new sub-TLV to be carried in the PCED capability
         sub-TLV if the capability needs more than just a single flag to be
         described.
      
         4.3. AS-DOMAIN sub-TLV
      
         When the PCE can perform path computation for an inter-AS TE LSP, the
         A bit of the PCE-CAPABILITY sub-TLV MUST be set. Moreover, one or
         more sub-TLVs MUST be included within the PCED sub-TLV, each sub-TLV
         identifying an AS number. Each AS-DOMAIN sub-TLV has the following
         form:
      
            CODE: 3
            LENGTH: 4
      
      
          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
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
          |                           AS Number                           |
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      
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                                    AS-DOMAIN sub-TLV format
      
         The AS-DOMAIN sub-TLV type is 3, length is 4 octets, and the value is
         the AS number identifying the AS for which the PCE can compute inter-
         AS TE LSP paths (TE LSP having their destination address in this AS).
         When coded on four bytes, the AS Number field MUST have its
         left two bytes set to 0.
      
         The set of AS-DOMAIN sub-TLVs specifies a list of ASes (AS1,à,
         ASn). This means that the PCE can compute TE LSP path such that the
         destination address of the TE LSP belongs to this set of ASes.
      
      5. TE-Mesh-Group sub-TLV format
      
         The TE-MESH-GROUP sub-TLV has the following format:
      
            CODE: 2
            LENGTH: Variable (N*8 octets)
      
            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
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |                        mesh-group-number                      |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |                        Tail-end address                       |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
            |                        Tail-end name                          |
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
           //                                                               //
            +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      
                                    TE-MESH-GROUP sub-TLV format
      
            N is the number of mesh-groups.
      
         For each Mesh-group announced by an LSR, the TLV contains:
            - A mesh-group-number: identifies the mesh-group number,
            - A Tail-end address: user configurable IP address to be used as a
            tail-end address by other LSRs belonging to the same mesh-group.
            - A Tail-end name: 32-bits string which facilitates the TE LSP
            identification which can be very useful in inter-area/AS MPLS TE
            environments.
      
      6. Element of procedure
      
         The sub-TLVs defined in this document are carried within the IS-IS
         CAPABILITY TLV defined in [IS-IS-CAP].
      
         An IS-IS router MUST originate a new IS-IS LSP whenever the content
         of the any of the carried sub-TLV changes or whenever required by the
         regular IS-IS procedure (LSP refresh).
      
      
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         If the flooding scope of an MPLS Traffic Engineering capability is
         limited to an IS-IS level/area, the S flag of the CAPABILITY TLV MUST
         be cleared. Conversely,if the flooding scope of an MPLS Traffic
         Engineering capability is the entire routing domain, the S flag of
         the CAPABILITY TLV MUST be set.
      
         In both cases the flooding rules as specified in [IS-IS-CAP] apply.
      
         As specified in [IS-IS-CAP], a router may generate multiple IS-IS
         CAPABILITY TLVs within an IS-IS LSP with different flooding scopes.
      
         6.1. TE-NODE-CAP sub-TLV
      
         The flooding scope is defined on a per capability basis.
      
         If the capability must be flooded within a single IS-IS area/level,
         the TE-NODE-CAP sub-TLV MUST be carried within a CAPABILITY TLV
         having the S flag cleared. Conversely, if the capability must be
         flooded throughout the entire routing domain, the TE-NODE-CAP sub-TLV
         MUST be carried within a CAPABILITY TLV having the S flag set.
      
         Capabilities with an identical flooding scope MUST be flooded within
         the same TE-NODE-CAP sub-TLV.
      
      
         6.2. PCED sub-TLV
      
         If the PCE can compute an intra-area TE LSP path, the L bit of the
         PCE-CAPABILITY sub-TLV of the PCED TLV MUST be set. The PCED sub-TLV
         MUST be carried within a CAPABILITY TLV having the S flag cleared.
      
         If the PCE can compute an inter-area TE LSP path, the I bit of the
         PCE-CAPABILITY sub-TLV of the PCED TLV MUST be set. The PCED sub-TLV
         MUST be carried:
      
            - Within a CAPABILITY TLV having the S flag cleared if the PCE can
             compute an inter-area TE LSP path for the LSRs in the area(s) it
             resides in (for instance the PCE is an ABR computing an inter-
             area TE LSP path for its area).
      
            - Within a CAPABILITY TLV having the S flag set if the PCE can
              compute an inter-area TE LSP path for the whole domain.
      
         If the PCE can compute an inter-AS TE LSP path, the A bit of the PCE-
         CAPABILITY sub-TLV of the PCED TLV MUST be set and the PCED TLV MUST
         be carried within CAPABILITY TLV having the S flag set.
      
         Note: if the PCE can compute both intra and inter-area TE LSP paths,
         both the L and I bits of the PCE-CAPABILITY sub-TLV MUST be set. The
         flags are not exclusive.
      
         If the PCE can compute inter-as TE-LSPs path, both the A bit of the
      
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         PCED TLV MUST and the S bit of CAPABILITY TLV MUST be set.
      
      
            Example
      
      
          -----------------AS1-----------------
      
         R1(L1)------R3(L1L2)*-----R4(L1L2)*----|                ------------
          |           |                |        |                |          |
          |  S1(L1)   |    S2(L1)      | ASBR1*(L1)--eBGP--ASBR2-|    AS2   |
          |           |                |        |                |          |
         R2(L1)------R5(L1L2)*-----R6(L1L2)-----|                ------------
      
            The areas contents are not detailed.
      
         Assumptions:
         - the * indicates a Path Computation Element capability
         - R3 is a PCE for level 1 only
         - R5 is a PCE for intra and inter-area TE LSP path computation for
           both levels
         - R4 is a PCE for inter-area TE LSP path computation only for both
            levels
         - S1 is a PCE for level 1 only
         - S2 is a PCE for the whole AS
         - ASBR1 is a PCE for inter-AS TE LSPs whose destination resides in
           AS2 (not for intra or inter-area area TE LSPs).
      
          In the example above:
          - S1 originates a level 1 LSP containing a PCED sub-TLV with:
               o The L bit of the PCE-CAPABILITY sub-TLV set,
               o The I and A bits of the PCE-CAPABILITY sub-TLV cleared.
          The S bit of the CAPABILITY TLV MUST be cleared.
      
          - S2 originates a level 2 LSP containing
               -an IS-IS CAPABILITY TLV with the S flag cleared carrying:
                a PCED TLV with:
                     - The L, and I bits of the PCE-CAPABILITY sub-TLV set,
                     - The A bit of the PCE-CAPABILITY sub-TLV cleared
               -an IS-IS CAPABILITY TLV with the S flag set carrying:
                 a PCED TLV with
                      -The I bit set
                      -The L and A bit cleared
      
          - ASBR1 originates a level1 LSP containing a PCED TLV with:
              o The L and I bits of the PCE-CAPABILITY sub-TLV cleared,
              o The A bit of the PCE-CAPABILITY sub-TLV set,
              o One AS-domain sub-TLV within the PCED sub-TLV with AS number =
                AS2
          The S bit of the CAPABILITY TLV MUST be set
      
          - R3 originates:
      
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            * a level 1 LSP containing
               - an IS-IS CAPABILITY TLV with the S flag cleared carrying:
                 o a PCED TLV describing its own PCE capability with:
                         - The L bit of the PCE-CAPABILITY sub-TLV set,
                         - The I and A bits of the PCE-CAPABILITY sub-TLV
                         cleared,
               - an IS-IS CAPABILITY TLV with the S flag set carrying:
                 o the S2's PCED TLV (with I and A bit unchanged)
                 o the ASBR1s PCED TLV (unchanged), leaked from level-2 LSP (S
                   bit set).
      
            * a level 2 LSP including no PCED TLV
      
            - R5 originates:
      
            * a level1 LSP containing:
               - an IS-IS CAPABILITY TLV with the S flag cleared carrying:
                 o a PCED TLV describing its own PCE capability with:
                         - The L and I bits of the PCE-CAPABILITY sub-TLV set,
                         - The A bit of the PCE-CAPABILITY sub-TLV cleared,
               - an IS-IS CAPABILITY TLV with the S flag set carrying:
                 o the S2's PCED TLV (with the I, A and L bits of the PCE-
                 CAPABILITY sub-TLV unchanged)
                 o the ASBR1's PCED TLV (unchanged)
      
            * a level 2 LSP containing an IS-IS CAPABILITY TLV with the S flag
            cleared carrying:
               o a PCED sub-TLV describing its own PCED capability with:
                 - Both the L and I bit of the PCE-CAPABILITY sub-TLV set,
                 - The A bit of the PCE-CAPABILITY sub-TLV cleared.
      
         The receipt of an IS-IS LSP containing a new PCED TLV never triggers
         an SPF calculation.
      
         When a PCE is newly configured, the corresponding PCED TLV MUST be
         immediately flooded.
      
         When a PCE looses its capability or when one of its PCED capabilities
         changes, the IS-IS LSP MUST be immediately flooded.
      
         6.3. TE-MESH-GROUP sub-TLV
      
         If the MPLS TE mesh-group is contained within a single IS-IS
         level (all the LSRs have their head-end and tail-end LSR within
         the same IS-IS level), the TE-MESH-GROUP sub-TLV MUST be carried
         within a CAPABILITY TLV having the S flag cleared. Conversely, if the
         MPLS TE mesh-group spans multiple IS-IS levels, the TE-
         MESH-GROUP sub-TLV MUST be carried within a CAPABILITY TLV having the
         S flag set.
      
      
      
      
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      7. Interoperability with routers not supporting the IS-IS MPLS TE
         capabilities
      
         There is no interoperability issue as a router not supporting the
         PCED, TE-MESH-GROUP or TE-NODE-CAP sub-TLVs SHOULD just silently
         ignore those sub-TLVs.
      
      8. Security considerations
      
       No new security issues are raised in this document.
      
      9. Intellectual Property Statement
      
         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.
      
      10. References
      
         Normative references
      
         [RFC] Bradner, S., "Key words for use in RFCs to indicate
         requirements levels", RFC 2119, March 1997.
      
         [RFC3667] Bradner, S., "IETF Rights in Contributions", BCP 78,
         RFC 3667, February 2004.
      
         [RFC3668] Bradner, S., Ed., "Intellectual Property Rights in IETF
         Technology", BCP 79, RFC 3668, February 2004.
      
         [ISIS] "Intermediate System to Intermediate System Intra-Domain
         Routing Exchange Protocol " ISO 10589.
      
      
      
      
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      Internet Draft    draft-vasseur-isis-te-caps-00.txt         July 2004
      
      
      
         [ISIS-IP] Callon, R., "Use of OSI IS-IS for routing in TCP/IP and
         dual environments", RFC 1195, December 1990.
      
         [ISIS-TE] Li, T., Smit, H., "IS-IS extensions for Traffic
         Engineering", RFC 3784, June 2004.
      
         [ISIS-CAP] Vasseur, J.P., Aggarwal, R., Shen, N. et al. "IS-IS
         extensions for advertising router information", draft-vasseur-isis-
         caps-02.txt, work in progress.
      
         [TE-INFO] Vasseur, J.P., Le Roux, J.L., et al., "Routing extensions
         for discovery of TE router information", draft-vasseur-ccamp-te-
         router-info-00.txt, work in progress.
      
         Informative References
      
         [ISIS-G] Kompella, K., Rekhter, Y., "IS-IS extensions in support of
         Generalized Multi-protocol Label Switching", draft-ietf-isis-gmpls-
         extensions-19.txt, work in progress.
      
         [INT-AREA-REQ] Le Roux, J.L., Vasseur, J.P., Boyle, J., "Requirements
         for inter-area MPLS Traffic Engineering", draft-ietf-tewg-interarea-
         mpls-te-req-02.txt, work in progress.
      
         [INT-AS-REQ] Zhang, R., Vasseur, J.P., "MPLS Inter-AS Traffic
         Engineering Requirements", draft-ietf-tewg-interas-mpls-te-req-
         07.txt, work in progress.
      
         [INT-DOMAIN-FRWK] Farrel, A., Vasseur, J.P., Ayyangar, A., "A
         Framework for Inter-Domain MPLS Traffic Engineering", draft-farrel-
         ccamp-inter-domain-framework-01.txt, work in progress.
      
         [P2MP-Req] Yasukawa, S., et. al., "Requirements for point-to-
         multipoint extension to RSVP-TE", draft-ietf-mpls-p2mp-requirement-
         02.txt, work in progress.
      
         [RSVP-TE] Awduche, D., et. al., "RSVP-TE: Extensions to RSVP for LSP
         tunnels", RFC 3209, December 2001.
      
         [RSVP-G] Berger, L, et. al., "GMPLS Signaling RSVP-TE extensions",
         RFC 3473, January 2003.
      
         [RSVP-P2MP] Aggarwal, Papadimitriou, Yasukawa, et. al. "Extensions to
         RSVP-TE for point-to-multipoint TE LSPs", draft-dry-mpls-rsvp-te-
         p2mp-00.txt, work in progress.
      
      
      11. Authors' Address:
      
         Jean-Philippe Vasseur
         Cisco Systems, Inc.
         300 Beaver Brook Road
      
      Vasseur, Le Roux et al.                                      [Page 13]


      Internet Draft    draft-vasseur-isis-te-caps-00.txt         July 2004
      
      
      
         Boxborough , MA - 01719
         USA
         Email: jpv@cisco.com
      
         Jean-Louis Le Roux
         France Telecom
         2, avenue Pierre-Marzin
         22307 Lannion Cedex
         FRANCE
         Email: jeanlouis.leroux@francetelecom.com
      
         Stefano Previdi
         Cisco Systems, Inc.
         Via Del Serafico 200
         00142 - Roma
         ITALY
         Email: sprevidi@cisco.com
      
         Paul Mabey
         Qwest Communications
         950 17th Street,
         Denver, CO 80202
         USA
         Email: pmabey@qwest.com
      
      Full Copyright Statement
      
      Copyright (C) The Internet Society (2004).  This document is subject to
      the rights, licenses and restrictions contained in BCP 78, and except as
      set forth therein, the authors retain all their rights.
      
      This document and the information contained herein are provided on an
      "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS OR
      IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY AND THE INTERNET
      ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS OR IMPLIED,
      INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF THE
      INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
      WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      
      Vasseur, Le Roux et al.                                      [Page 14]
      

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