One document matched: draft-vasseur-ospf-te-caps-00.txt


      OSPF Working Group                                           JP Vasseur  
      Internet Draft                                             Peter Psenak 
                                                             Cisco System Inc. 
                                                              Seisho Yasukawa 
                                                                           NTT 
                                                           Jean-Louis Le Roux 
                                                                France Telecom 
                                                       
                                                       
                                                                               
      Category: Standard Track                                                 
      Expires: January 2005                                          July 2004 
       
       
                    OSPF MPLS Traffic Engineering capabilities  
          
                     draft-vasseur-ospf-te-caps-00.txt 
       
       
      Status of this Memo 
       
         By submitting this Internet-Draft, I certify that any applicable 
         patent or 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 OSPF traffic engineering capability TLVs 
         related to various MPLS Traffic Engineering capabilities. These OSPF 
         TE capability TLVs are carried within the OSPF router information LSA 
         (opaque type of 4, opaque ID of 0).  
          
       
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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 TLV format........................4 
         3.1. The DATA-PLANE-CAPABILITY sub-TLV.............................4 
         3.2. The CONTROL-PLANE-CAPABILITY sub-TLV..........................5 
         4. PCED TLV format.................................................5 
         4.1. PCE-ADDRESS sub-TLV...........................................6 
         4.2. PCE-CAPABILITY sub-TLV........................................6 
         4.3. AS-DOMAIN sub-TLV.............................................8 
         5. TE-Mesh-Group TLV format........................................8 
         6. Element of procedure............................................9 
         6.1. TE-NODE-CAP TLV...............................................9 
         6.2. PCED TLV.....................................................10 
         6.3. TE-MESH-GROUP TLV............................................12 
         7. Interoperability with routers non supporting this capability...12 
         8. Security considerations........................................12 
         9. Intellectual Property Statement................................12 
         9.1. IPR Disclosure Acknowledgement...............................13 
         10. References....................................................13 
         11. Authors' Address:.............................................14 
          
       
      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 OSPF protocol extensions and procedures for     
         the advertisement TE node capabilities. A functional description of  
         these extensions can be found in [TE-INFO], and is not repeated here. 
       
         This document describes the usage of three OSPF TE capabilities TLVs:  
         the PCED (PCE Discovery), the TE-MESH-GROUP and the TE-NODE-CAP  
         TLVs. These OSPF TE capability TLVs are carried within the OSPF  
         router information LSA (opaque type of 4, opaque ID of 0) specified  
         in [OSPF-CAP].  
              
         Each TE TLV defined in this document (carried in an OSPF router  
         information LSA as defined in [OSPF-CAP]) has 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             |             length            |  
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
           |                                                               |  
           //                            Value                            //         
           |                                                               |  
           +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
              
         Where   
            Type: identifies the TLV type  
            Length: length of the value field in octets  
              
         The format of the TLV is the same as the TLV format used by the  
         Traffic Engineering Extensions to OSPF [OSPF-TE]. The TLV is padded  
         to four-octet alignment; padding is not included in the length field  
         (so a three octet value would have a length of three, but the total  
         size of the TLV would be eight octets).  Nested TLVs are also 32-bit  
         aligned.  Unrecognized types are ignored.  All types between 32768  
         and 65535 are reserved for vendor-specific extensions.  All other  
         undefined type codes are reserved for future assignment by IANA.  
              
         Note that a sub-TLV is similar to a TLV: TLV are carried within an  
         LSA as sub-TLVs are carried within TLVs. Each sub-TLV describes a  
         particular MPLS Traffic Engineering capability. In the rest of this 
         document both terms will be used interchangeably.  
          


       
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         The TE-NODE-CAP 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 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 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 TLV format 
          
         This section specifies the sub-TLVs carried within the TE-NODE-CAP 
         TLV payload which defines the TE node capabilities.  
             
         The TE-NODE-CAP TLV type is 1. 
          
         The TE-NODE-CAP 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.  
          
         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:  
       
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         -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 detail 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  
              
         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 TLV format 
       
         This section specifies the sub-TLVs carried within the PCED TLV  
         payload which define the PCE capabilities.  
          
         The PCED TLV type is 2 
       
         The PCED TLV is made of various non ordered sub-TLVs defined  
       
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         bellow:  
                   
            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.  
           
              
         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.  
          
         The 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                        //       
             |                                                               |  
             +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
                                   
                                  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.  
       
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         The PCE-CAPABILITY sub-TLV type is 2 and the length is 8 octets.  
              
            CODE: 2  
            LENGTH: 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  
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
          |                       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 area/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  
         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  
       
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         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                           |  
          +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+  
              
                                    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 TLV format 
       
         The TE-MESH-GROUP TLV has the following format:  
          
              
       
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            CODE: 3  
            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 the 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 TLVs defined in this document are carried within an OSPF router  
         information opaque LSA (opaque type of 4, opaque ID of 0) as defined  
         in [OSPF-CAP].  
              
         A router MUST originate a new OSPF router information LSA whenever  
         the content of the any of the carried TLV changes or whenever  
         required by the regular OSPF procedure (LSA refresh (every  
         LSRefreshTime)).  
              
         As defined in RFC2370, an opaque LSA has a flooding scope determined  
         by its LSA type:  
               - link-local (type 9),   
               - area-local (type 10)   
               - entire OSPF routing domain (type 11). In this case, the  
               flooding scope is equivalent to the Type 5 LSA flooding scope.  
              
         A router may generate multiple OSPF router information LSAs with  
         different flooding scopes.  
           
         6.1. TE-NODE-CAP TLV  
              
         The TE-NODE-CAP may be carried within a type 10 or 11 router 
         information LSA depending on the MPLS Traffic Engineering capability. 
         The flooding scope is defined on a per capability basis. Capabilities 
       
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         with a identical flooding scope MUST be flooded within the same TE-
         NODE-CAP TLV carried within a router information LSA. 
           
         6.2. PCED TLV  
       
         The PCED TLV may be carried within a type 10 or 11 router information  
         LSA depending on the Path Computation Element scope.   
              
            - If the PCE can compute an intra-area TE LSP, the L bit of the  
              PCE-CAPABILITY TLV of the PCED TLV MUST be set and the PCED TLV  
              MUST be generated within a Type 10 router information LSA,  
                   
            - If the PCE can compute an inter-area TE LSP, the I bit of the  
              PCE-CAPABILITY TLV of the PCED TLV MUST be set. The PCED TLV  
              MUST be generated:  
                  - within a Type 10 router information LSA if the PCE can  
                    compute an inter-area TE LSP path for the LSRs in the  
                    area it is attached to (for instance the PCE is an ABR  
                    computing an inter-area TE LSP path for its attached     
                    areas)  
                   - within a Type 11 router information LSA 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 TLV of the PCED TLV MUST be set and the PCED  
              TLV MUST be generated within a Type 11 router information LSA,  
              
         Note: if the PCE can compute both intra and inter-area TE LSP   
         paths, both the L and I bits of the PCE-CAPABILITY TLV MUST be set. 
         The flags are not exclusive. This only applies to the PCED TLV 
         carried within the type 10 router information LSA.  
              
         If a PCE can compute an intra-area TE LSP and an inter-area or inter- 
         AS TE LSP path, it MUST originate:  
               - a type 10 OSPF router information LSA with a PCED TLV having  
                 the L, I and A flags of its PCE-CAPABILITY TLV set as 
                 described above. 
               - a type 11 OSPF router information LSA with a PCED TLV having  
                 L=0 and the I and A flags of its PCE-CAPABILITY TLV set as  
                 described above.  
              
            Example  
              
            <-----------------AS1----------------->  
              
            <---area 1--><----area 0-----><-area 2->  
              
         R1---------ABR1*------------ABR3*-----|                 ------------  
          |           |                |       |                 |          |  
          |     S1    |      S2        |     ASBR1*--eBGP--ASBR2-|    AS2   |  
          |           |                |       |                 |          |  
         R2---------ABR2*------------ABR4------|                 ------------  
       
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         The areas contents are not detailed.  
              
         Assumptions:  
         - area 1 and area 2 are regular areas  
         - the * indicates a Path Computation Element capability  
         - ABR1 is a PCE for area 1 only  
         - ABR2 is a PCE for intra and inter-area TE LSP path computation in  
         area 0 and 1  
         - ABR3 is a PCE for only inter-area TE LSP path computation for the  
         whole domain,  
         - S1 is a PCE for area 1 only  
         - S2 is a PCE for the whole domain,  
         - 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 type 10 router information LSA with a PCED TLV such  
         that:  
              o The L bit of the PCE-CAPABILITY TLV is set,  
              o The I and A bits of the PCE-CAPABILITY TLV are cleared.  
              
         - ABR1 originates in area 1 a type 10 router information LSA with a  
         PCED TLV such that:  
              o The L bit of the PCE-CAPABILITY TLV is set,  
              o The I and A bits of the PCE-CAPABILITY sub-TLV are cleared,  
              
         - ABR2 originates in both area 0 and 1 a type 10 router information  
         LSA with a PCED TLV such that:  
              o The L and I bits of the PCE-CAPABILITY TLV are set,  
              o The A bit of the PCE-CAPABILITY TLV  is cleared  
              
         - ABR3 originates a type 11 router information LSA with a PCED TLV  
          such that:  
              o The L bit of the PCE-CAPABILITY TLV is cleared,  
              o The I bit of the PCE-CAPABILITY TLV is set,  
              o The A bit of the PCE-CAPABILITY TLV is cleared,  
              
         - S2 originates:  
               - in area 0 a type 10 router information LSA with a PCED TLV  
                 such that:  
                     o The L and I bits of the PCE-CAPABILITY sub-TLV are  
                       set,  
                     o The A bit of the PCE-CAPABILITY TLV  is cleared,  
               - a type 11 router information LSA with a PCED TLV such that:  
                      o The L bit of the PCE-CAPABILITY TLV is cleared,   
                      o The I bit of the PCE-CAPABILITY TLV is set,  
                      o The A bit of the PCE-CAPABILITY TLV is cleared,  
              
         - ASBR1 originates a type 11 router information LSA with a PCED TLV  
         such that:  
       
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              o The L bit and the I bit of the PCE-CAPABILITY TLV are cleared,  
              o The A bit of the PCE-CAPABILITY TLV set,  
              o One AS-DOMAIN TLV within the PCED TLV with AS number = AS2  
              
         The receipt of a new router information LSA carrying a PCED TLV never  
         triggers an SPF calculation.  
              
         When an LSR or a Path Computation Element is newly configured as a  
         PCE, the corresponding router information LSA MUST be immediately  
         flooded.  
              
         When a PCE capability changes, the corresponding router information  
         LSA MUST be immediately flooded.  
              
         When a PCE looses its Path Computation Element capability, the  
         corresponding router information LSA MUST be immediately flooded with  
         LS age = MaxAge.  
              
         6.3. TE-MESH-GROUP TLV  
              
         The TE-MESH-GROUP TLV may be carried within a type 10 or 11 router  
         information LSA depending on the MPLS TE mesh-group profile:  
              
             - If the MPLS TE mesh-group is contained within a single area  
               (all the LSRs have their head-end and tail-end LSR within the  
               same OSPF area), the TE-MESH-GROUP TLV MUST be generated    
               within a Type 10 router information LSA,  
             - If the MPLS TE mesh-group spans multiple OSPF areas, the TE- 
               MESH-GROUP TLV MUST be generated within a Type 11 router  
               information LSA,  
               
      7. Interoperability with routers non supporting this capability  
           
         There is no interoperability issue as a router not supporting the TE-
         NODE-CAP, PCED or TE-MESH-GROUP TLVs SHOULD just silently discard  
         those TLVs as specified in RFC2370.  
              
      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. 
          
       
      Vasseur et al.                                               [Page 12] 
        


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         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..  
          
         9.1. IPR Disclosure Acknowledgement 
             
         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. 
          
      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. 
          
         [OSPF-v2] Moy, J., "OSPF Version 2", RFC 2328, April 1998. 
          
         [OSPF-TE] Katz, D., Yeung, D., Kompella, K., "Traffic Engineering 
         Extensions to OSPF Version 2", RFC 3630, September 2003. 
          
         [OSPF-CAP] Lindem, A., Shen, N., Aggarwal, R., Shaffer, S., Vasseur, 
         J.P., "Extensions to OSPF for advertising Optional Router 
         Capabilities", draft-ietf-ospf-cap-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 
          
         [OSPF-G] Kompella, K., Rekhter, Y., "OSPF extensions in support of 
         Generalized Multi-protocol Label Switching", draft-ietf-ccamp-ospf-
         gmpls-extensions-12.txt, work in progress. 
          
       
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         [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 (Editor) 
         Cisco Systems, Inc.  
         300 Beaver Brook Road  
         Boxborough , MA - 01719  
         USA  
         Email: jpv@cisco.com 
          
         Peter Psenak  
         CISCO Systems, Inc.  
         Pegasus Parc   
         De Kleetlaan 6A  
         1831, Diegem   
         BELGIUM  
         Email: ppsenak@cisco.com  
              
         Seisho Yasukawa  
         NTT Network Service Systems Laboratories, NTT Corporation  
         9-11, Midori-Cho 3-Chome  
         Musashino-Shi, Tokyo 180-8585 Japan  
         Phone: + 81 422 59 4769  
         Email: yasukawa.seisho@lab.ntt.co.jp  
          
         Jean-Louis Le Roux  
       
      Vasseur et al.                                               [Page 14] 
        


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         France Telecom  
         2, avenue Pierre-Marzin  
         22307 Lannion Cedex  
         FRANCE 
         Email: jeanlouis.leroux@francetelecom.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 et al.                                               [Page 15] 

PAFTECH AB 2003-20262026-04-22 22:49:33