CCAMP Working Group                                   Zafar Ali, Ed.
   Internet Draft                                   George Swallow, Ed.
   Intended status: Standard Track                        Cisco Systems
   Expires: January 3, April 26, 2015                                F. Zhang, Ed.
                                                                 Huawei
                                                         D. Beller, Ed.
                                                         Alcatel-Lucent
                                                           July 4,
                                                       October 27, 2014

       Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) Path
                         Diversity using Exclude Route

                     draft-ietf-ccamp-lsp-diversity-04.txt

                     draft-ietf-ccamp-lsp-diversity-05.txt

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   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt      draft-ietf-ccamp-lsp-diversity-05.txt

   Abstract

   RFC 4874 specifies methods by which path exclusions may can be
   communicated during RSVP-TE signaling in networks where precise
   explicit paths are not computed by the LSP source node. This
   document specifies procedures for additional route exclusion
   subobject based on Paths currently existing or expected to exist
   within the network.

   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 [RFC2119].

   Table of Contents

   1. Introduction ............................................... 2 ..................................................2
         1.1. Client Initiated Client-Initiated Identifier ........................ 5 ...........................5
         1.2. PCE allocated Identifiers .......................... 6 PCE-allocated Identifier ..............................6
         1.3. UNI-N allocated Identifiers ........................ 7 Network-Assigned Identifier ...........................7
   2. RSVP-TE signaling extensions ............................... 9 ..................................9
         2.1. Diversity XRO Subobject ............................ 9 ...............................9
             2.1.1. Tunnel identifier TLVs ........................... 12 IPv4 Diversity XRO Subobject ....................9
             2.1.2. Path Key TLVs .................................... 14
         2.1.3. Path Affinity Set TLVs ........................... 16 IPv6 Diversity XRO Subobject ...................14
         2.2. Processing rules for the Diversity XRO subobject ... 19
         2.2.1. Processing rules for the tunnel identifier TLVs .. 20
         2.2.2. Processing rules for the Path Key TLVs ........... 22
         2.2.3. Processing rules for the PAS TLVs ................ 23 .....17
         2.3. Diversity EXRS Subobject ........................... 25 .............................20
   3. Security Considerations .................................... 27 ......................................22
   4. IANA Considerations ........................................ 27 ..........................................22
         4.1. New XRO subobject types ..............................22
         4.2. New EXRS subobject types .............................23
         4.3. New RSVP error sub-codes .............................23
   5. Acknowledgements .............................................23
   6. References ................................................. 28 ...................................................24
         6.1. Normative References ............................... 28 .................................24
         6.2. Informative References ............................. 29 ...............................24

   1. Introduction

      Path diversity for multiple connections is a well-known Service
      Provider requirement. Diversity constraints ensure that Label-
      Switched Paths (LSPs) may can be established without sharing

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt
      resources, thus greatly reducing the probability of simultaneous
      connection failures.

      When a source node has full topological knowledge and is permitted
      to signal an Explicit Route Object (ERO), Object, diverse paths for LSPs can be
      computed locally. by this source node. However, there are scenarios when

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      path computations are performed by remote different nodes, thus and there is
      therefore a need for relevant diversity constraints to be
      communicated to those nodes. These include (but are not limited
      to):

      .  LSPs with loose hops in the ERO, Explicit Route Object (ERO), e.g.
        inter-domain LSPs;

      .  Generalized Multi-Protocol Label Switching (GMPLS) User-
        Network Interface (UNI) (UNI), where path computation may be
        performed by the core node [RFC4208].

      [RFC4874] introduced a means of specifying nodes and resources to
      be excluded from a route, using the eXclude Route Object (XRO) and
      Explicit Exclusion Route Subobject (EXRS). It facilitates the
      calculation of diverse paths for LSPs based on known properties of
      those paths including addresses of links and nodes traversed, and
      Shared Risk Link Groups (SRLGs) of traversed links. Employing
      these mechanisms requires that the source node that initiates
      signaling knows the relevant properties of the path(s) from which
      diversity is desired. However, there are circumstances under which
      this may not be possible or desirable, including (but not limited
      to):

      .  Exclusion of a path which does not originate, terminate or
         traverse the source node signaling of the diverse LSP, in which case the
         addresses of links and SRLGs of the path from which diversity
         is required are unknown to the source node.

      .  Exclusion of a path which is known to the source node of the
         diverse LSP, however LSP for which the node has incomplete or no path
         information, e.g. due to operator policy. In other words, this case, the scenario
         in which
         existence of the reference path is known by to the source / requesting node but
         the properties information required to construct an XRO object are to
         guarantee diversity from the reference path is not fully known.
         Inter-domain and GMPLS overlay networks can present such
         restrictions.

      This is exemplified in the Figure 1, where overlay reference
      model from [RFC4208] is shown.

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     Overlay                                                  Overlay
     Network       +----------------------------------+       Network
   +---------+     |                                  |     +---------+
   |  +----+ |     |  +-----+    +-----+    +-----+   |     | +----+  |
   |  |    | | UNI |  |     |    |     |    |     |   | UNI | |    |  |
   | -+ EN1+-+-----+--+ CN1 +----+ CN2 +----+ CN3 +---+-----+-+ EN3+- |
   |  |    | |  +--+--+     |    |     |    |     |   | +---+-|    |  |
   |  +----+ |  |  |  +--+--+    +--+--+    +--+--+   | |   | +----+  |
   +---------+  |  |     |          |          |      | |   +---------+
                |  |     |          |          |      | |
   +---------+  |  |  +--+--+       |       +--+--+   | |   +---------+
   |  +----+ |  |  |  |     |       +-------+     +-----+   | +----+  |
   |  |    +-+--+  |  | CN4 +---------------+ CN5 |   |     | |    |  |
   | -+ EN2+-+-----+--+     |               |     +---+-----+-+ EN4+- |
   |  |    | | UNI |  +-----+               +-----+   | UNI | |    |  |
   |  +----+ |     |                                  |     | +----+  |
   +---------+     +----------------------------------+     +---------+
     Overlay                 Core Network                     Overlay
     Network                                                  Network

                           Legend:   EN  -  Edge Node
                                     CN  -  Core Node

                  Figure 1:  Overlay Reference Model [RFC4208]

      Figure 1 depicts two types of UNI connectivity: single-homed and
      dual-homed ENs (which also applies to higher order multi-homed
      connectivity.). Single-homed Edge Node (EN) EN devices are connected to a single Core Node (CN)
      CN device via a single UNI link. This single UNI link may
      constitute a single point of failure. UNI connection between EN1
      and CN1 is an example of singled-homed UNI connectivity.

      A single point of failure caused by a single-homed UNI can be
      avoided when the EN device is connected to two different CN
      devices, as depicted for EN2 in Figure 1. For the dual-homing
      case, it is possible to establish two different UNI connections
      from the same source EN device to the same destination EN device.
      For example, two connections from EN2 to EN3 may use the two UNI
      links EN2-CN1 and EN2-CN4. To avoid single points of failure
      within the provider network, it is necessary to also ensure path
      (LSP) diversity within the core network.

      In a UNI network such as that shown in Figure 1, the CNs
      typically performs perform path computation. Information sharing across

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      the UNI boundary is restricted based on the policy rules imposed
      by the core network. Typically, the

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt core network topology
      information is not exposed to the ENs. In
      such networks, the network shown in
      Figure 1, consider a use case where an LSP from EN2 to EN4 needs
      to be SRLG diverse from an LSP from EN1 to EN3. In this case, EN2
      may not know SRLG attributes of the EN1- EN3 LSP and hence cannot
      construct an XRO to exclude these SRLGs. In this example EN2
      cannot use the procedures described in [RFC4874]. Similarly, in the context of dual-homed UNI example described
      above, an
      LSP from EN2 to EN3 going via traversing CN1 needs to be diverse from an
      LSP from EN2 to EN3 going via CN4. Again in this case,
      [RFC4874] based exclusions
      based on [RFC4874] cannot be used.

      This document addresses these diversity requirements by
      introducing the notion of excluding the path taken by particular
      LSP(s). The reference LSP(s) with or route(s) from which diversity is
      required is is/are identified by an "identifier". The type of
      identifier to use is highly dependent on the networking
      deployment scenario. For
      example, if the identifier is client initiated, scenario; it could be client-initiated, allocated by
      the (core) network
      allocates identifier or managed by a Path Computation Element (PCE) manages
      identifier. Consequently, this PCE. This document defines
      three different types of identifiers: identifiers corresponding to these three
      cases: a client initiated identifier, a PCE allocated Identifier
      and network CN ingress node (UNI-N) allocated Identifier, as detailed in the
      following sections. Identifier.

   1.1. Client Initiated Client-Initiated Identifier

      There are scenarios in which the ENs have the following
      requirements for the diversity identifier:

      -  The identifier is controller controlled by the client side and is
         specified as part of the service request.

      -  Both client and server should understand the identifier.

      -  The identifier needs  It is necessary to be reference able to reference the identifier even if
         the LSP referenced by it is not yet signaled.

      -  The identifier should is to be stable for a long period of time.

      -  The identifier should is to be stable even when the referenced tunnel
         is rerouted.

      -  The identifier should is to be human readable.

      The above-mentioned human-readable.

      These requirements are met by using RSVP the Resource ReserVation
      Protocol (RSVP) tunnel/ LSP Forwarding Equivalence Class (FEC) as
      the identifier.
      Consequently, RSVP tunnel/ LSP FEC is used as client initiated
      identifier.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt      draft-ietf-ccamp-lsp-diversity-05.txt

      The usage of the client-initiated identifier is illustrated by
      using Figure 1. Suppose a tunnel from EN2 to EN4 needs to be
      diverse with respect to a tunnel from EN1 to EN3. Lets assume The tunnel FEC
      of the EN1-EN3 tunnel is FEC1, where FEC1 is defined by the tuple
      (tunnel-id = T1, source address = EN1.ROUTE Identifier (RID),
      destination address = EN3.RID, extended tunnel-
      id tunnel-id = EN1.RID).
      Similarly, tunnel FEC of the EN2-EN3 tunnel is FEC2, where FEC2
      is defined by the tuple (tunnel-id = T2, source address =
      EN2.RID, destination address = EN4.RID, extended tunnel-id =
      EN2.RID). The EN1-EN3 tunnel is signaled such that it
      specifies the with an exclusion
      requirement from FEC2. Similarly, EN2-EN3
      tunnel FEC2, and the EN2-EN3 tunnel is signaled such that it specifies the with an
      exclusion requirement from FEC1. In order to maintain diversity
      between these two connections within the core network, it is
      assumed that the core network implements Crank back Crankback Signaling
      [RFC4920].
      Similarly, diversity within the core network for a dual homed UNI
      case Note that crankback signaling is satisfied known to lead to
      slower setup times and sub-optimal paths under some circumstances
      as described by the use of Crank back Signaling [RFC4920].

   1.2. PCE allocated Identifiers PCE-allocated Identifier

      In scenarios where a PCE is deployed and used to perform path
      computation, the core edge node (e.g., node CN1 in Figure 1)
      could consult a PCE to allocate identifiers, which are used to
      signal path diversity constraints. In other scenarios a PCE is
      deployed in each border node or a PCE is part of the a Network
      Management System (NMS). In all these cases, the Path key Key as
      defined in [RFC5520] can be used in RSVP signaling as the
      identifier to ensure diversity.

      The usage

      An example of specifying LSP diversity using a Path Key is
      exemplified shown
      in Figure 2, where a simple network with two domains is shown. It
      is desired to set up a pair of path-disjoint LSPs from the source
      in Domain 1 to the destination in Domain 2, but the domains keep
      strict confidentiality about all path and topology information.

      The first LSP is signaled by the source with ERO {A, B, loose Dst}
      and is set up with the path {Src, A, B, U, V, W, Dst}. However,
      when sending the RRO out of Domain 2, node U would normally strip
      the path and replace it with a loose hop to the destination. With
      this limited information, the source is unable to include enough
      detail in the ERO of the second LSP to avoid it taking, for
      example, the path {Src, C, D, X, V, W, Dst} for path-disjointness.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt      draft-ietf-ccamp-lsp-diversity-05.txt

          ---------------------    -----------------------------
         | Domain 1            |  |                    Domain 2 |
         |                     |  |                             |
         |        ---    ---   |  |   ---    ---     ---        |
         |       | A |--| B |--+--+--| U |--| V |---| W |       |
         |      / ---    ---   |  |   ---    ---     --- \      |
         |  ---/               |  |          /       /    \---  |
         | |Src|               |  |         /       /     |Dst| |
         |  ---\               |  |        /       /      /---  |
         |      \ ---    ---   |  |   --- /   --- /  --- /      |
         |       | C |--| D |--+--+--| X |---| Y |--| Z |       |
         |        ---    ---   |  |   ---     ---    ---        |
         |                     |  |                             |
          ---------------------    -----------------------------

                Figure 2: 1: A Simple Multi-Domain Network

      In order to improve the situation, node U performs the PCE
      function and replaces the path segment {U, V, W} in the RRO with
      a Path Key Subobject [RFC5553]. Subobject. The Path Key Subobject assigns an
      "identifier" to the key. The PCE ID in the message indicates that
      it was node U that made the replacement.

      With this additional information, the source is able to signal
      the subsequent LSPs with the ERO set to {C, D, exclude Path
      Key(EXRS), loose Dst}. When the signaling message reaches node X,
      it can consult node U to expand the Path Key and know how to
      avoid the path of the first LSP. Alternatively, the source could
      use an ERO of {C, D, loose Dst} and include an XRO containing the
      Path Key.

      This mechanism can work with all the Path-Key resolution
      mechanisms, as detailed in [RFC5553] section 3.1. A PCE, co-
      located or not, may be used to resolve the Path-Key, but the node
      (i.e., a Label Switching Router (LSR)) can also use the Path Key
      information to index a Path Segment previously supplied to it by
      the entity that originated the Path-Key, for example the LSR that
      inserted the Path-Key in the RRO or a management system.

   1.3. Network allocated Identifiers Network-Assigned Identifier

      There are scenarios in which the network provides diversity diversity-
      related information for a service that allows the client device
      to include this information in the signaling message. In this
      section two signaling approaches are outlined that use network
      allocated identifiers. While both methods could be implemented in
      the same core network, it is very likely that a core network
      supports only one of If the two mechanisms.

      The first method assumes that core network
      Shared Resource Link Group (SRLG) identifier information is both
      available and shareable (by policy) with the ENs. In this case, ENs, the procedure

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      defined in [DRAFT-SRLG-RECORDING] can be used to collect SRLG
      identifiers associated with an LSP (say LSP1). Suppose that LSP2

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt (LSP1). When a second LSP
      (LSP2) needs to be diverse with respect to LSP1. When LSP1, the EN constructs
      constructing the RSVP signaling message for setting up LSP2, it LSP2 can
      insert the SRLG identifiers associated with LSP1 as diversity
      constraints into the XRO using the procedure described in
      [RFC4874]. This
      method is not discussed further as it utilizes existing RSVP
      protocol mechanisms for collecting SRLG information and passing
      this diversity information to However, if the CN.

      The second method assumes that core network SRLG identifiers are
      either not available or not shareable with the ENs based on
      policies enforced by core network. network, existing mechanisms cannot be
      used.

      In this case, draft, a signaling mechanism is defined where information
      signaled to the CN via the UNI does not require shared knowledge
      of provider core network SRLG information. For this purpose, notion the concept
      of a Path Affinity Set (PAS) is used for abstracting SRLG
      information. The motive behind the introduction of the PAS information is to have as little
      minimize the exchange of diversity information as possible between the core
      network (CNs) and the client devices (ENs). I.e., rather than a detailed SRLG list, the The PAS contains an
      abstract SRLG identifier associated with a given
      path.

      There are two types of diversity information in the PAS. path rather than
      a detailed SRLG list. The
      first type of information PAS is a single PAS identifier. The Second
      part is the optional PATH information, in the form of Source and
      Destination addresses of a path. This mechanism identifier that can also be
      applied
      used to L1 VPNs request diversity and in this particular case, associate diversity. The means by
      which the identifier
      only needs processing node determines the path corresponding to be unique within
      the PAS is beyond the scope of a particular VPN. this document.

      A CN on the core network boundary interprets the specific PAS
      identifier, for example, "123"
      identifier (e.g. "123") as meaning to exclude the core network
      SRLG information (or equivalent) that has been allocated by LSPs
      associated with this PAS identifier value. For example, if a Path
      exists for the LSP with the identifier "123", the CN would use
      local knowledge of the core network SRLGs associated with the
      "123" LSPs and use those SRLGs as constraints for path
      computation.  In other words, two LSPs that need to be diverse
      both signal "123" and the CNs interpret this as meaning not to
      use shared resources.  Alternatively, If a CN could use the PAS identifier to select from already established LSPs. Once the path is established core network allocated the "123" identifier or
      optionally another PAS identifier for that VPN that replaces
      "123".

      The optional PAS source and destination address tuple represents
      one or more source addresses and destination addresses associated
      with the EN PAS identifier. These associated address tuples
      represent paths that use resources that should be excluded included for

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      the establishment of the current LSP.  The address tuple
      information gives both finer grain details on the path diversity
      request and serves as an alternative identifier exclusion in the case when
      the PAS identifier is not known by
      connection request, the CN.  The address tuples
      used CN (UNI-N) in signaling is within a client the core network context and its
      interpretation is local to a CN that receives a Path request from
      an EN. The CN can use the address information assumed
      to relate be able to CN
      addresses and determine the existing core network SRLG information.
      information and calculate a path that meets the determined
      diversity constraints.

      When a CN satisfies a connection setup for a (SRLG) diverse
      signaled path, the CN may optionally record the core network SRLG
      information for that connection in terms of CN based parameters
      and associates that with the EN addresses in the Path message.
      Specifically for
      L1VPNs, Layer-1 Virtual Private Networks (L1VPNs), Port
      Information tables Tables (PIT) [RFC5251] can be leveraged to translate
      between client (EN) based addresses and core network
      based addresses.

      The PAS and the associated core network addresses
      with core network SRLG information can be distributed via the IGP
      in
      within the core network (or by an Interior Gateway Protocol (IGP) or

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      by other means such as configuration);
      they configuration. They can then be utilized
      by other CNs when other ENs are requesting paths to be setup that
      would require path/connection diversity. In the VPN case, this
      information is distributed on a VPN basis and contains a PAS
      identifier, CN addresses and SRLG information.

      If diversity is not signaled, the assumption is that no diversity
      is required and In this way, on a
      VPN basis, the core network is free to route the LSP to
      optimize traffic. No Path affinity set information needs to be
      recorded can have additional opaque records
      for these LSPs.  If a diversity object is included in the connection request, PAS values for various Paths along with the CN in SRLG list
      associated with the core network should be able Path. This information is internal to determine (look-up) the existing
      core network SRLG information and choose an LSP that is maximally diverse from other LSPs.

      The Path Affinity Set identifier is independent of the mechanism
      the EN or the CN use for diversity. The Path Affinity Set is a
      single identifier that can be used known only to request diversity and
      associate diversity. the core network.

   2. RSVP-TE signaling extensions

      This section describes the signaling extensions required to
      address the aforementioned requirements and use cases.

   2.1. Diversity XRO Subobject

      New Diversity XRO subobjects are defined by this document as
      follows.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

   2.1.1. IPv4 Diversity XRO Subobject

        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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |L|  XRO Type     |Attribute Flags|Exclusion Flags|    Reserved   |     Length    |DI Type|A-Flags|E-Flags| Resvd |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                            TLVs ...           IPv4 Diversity Identifier source address            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  Diversity Identifier Value                   |
      //                            ...                              //
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        L:
             The L-flag is used as for the XRO subobjects defined in
             [RFC4874], i.e.,

             0 indicates that the attribute specified MUST be excluded.

             1 indicates that the attribute specified SHOULD be avoided.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

        XRO Type

             Type for IPv4 diversity XRO subobject (to be assigned by
             IANA; suggested value: 37).

        Length

             The Length contains the total length of the subobject in
             bytes, including the Type and Length fields. The Length is
             variable, depending on the diversity identifier value.

        Diversity Identifier Type (DI Type)

             Diversity Identifier Type (DI Type) indicates the way the
             reference LSP(s) or route(s) with which diversity is
             required is identified. Three values are defined in this
             document:

             IPv4 Client Initiated Identifier   1 (to be assigned by
             IANA)
             IPv4 PCE Allocated Identifier      2 (to be assigned by
             IANA)
             IPv4 Network Assigned Identifier   3 (to be assigned by
             IANA)

        Attribute Flags: Flags (A-Flags):

            The Attribute Flags (A-Flags) are used to communicate
            desirable attributes of the LSP being signaled. The
            following flags are defined. Each flag acts independently.
            Any combination of flags is permitted.

            0x01 = Destination node exception

               Indicates that the exclusion does not apply to the
               destination node of the LSP being signaled.

            0x02 = Processing node exception

               Indicates that the exclusion does not apply to the
               border node(s) performing ERO expansion for the LSP
               being signaled. Ingress An ingress UNI-N node is an example of
               such
               nodes. a node.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

            0x04 = Penultimate node exception

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

               Indicates that the penultimate node of the LSP being
               signaled MAY be shared with the excluded path even when
               this violates the exclusion flags.

            0x08 = LSP ID to be ignored

               This flag is only applicable to when the IPv4/ IPv6 Point-to-
               Point tunnel identifier TLVs of diversity is
               specified using the Diversity XRO
               subobjects defined in section 2.1.1. In this context, client-initiated identifier, the
               flag indicates tunnel level exclusion. Specifically,
               this flag is used to indicate that the lsp-id field of
               the IPv4/ IPv6 Point-to-Point tunnel identifier TLVs is
               to be ignored and the exclusion applies to any LSP
               matching the rest of the supplied FEC. exclusion, as detailed in
               section 2.2.

        Exclusion Flags (E-Flags):

             The Exclusion-Flags are used to communicate the desired
             type(s) of exclusion. The following flags are defined. Any
             combination of these flags is permitted.

             0x01 = SRLG exclusion

                  Indicates that the path of the LSP being signaled is
                  requested to be SRLG diverse SRLG-diverse from the excluded path
                  specified by the Diversity XRO subobject.

             0x02 = Node exclusion

                  Indicates that the path of the LSP being signaled is
                  requested to be node diverse node-diverse from the excluded path
                  specified by the Diversity XRO subobject.

                  (Note: the meaning of this flag may be modified by
                  the value of the Attribute-flags.)

             0x04 = Link exclusion

                  Indicates that the path of the LSP being signaled is
                  requested to be link diverse link-diverse from the path specified
                  by the Diversity XRO subobject.

        Resvd

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

         TLVs (Type-Length-Value tuples) have the following format. Only
      one TLV      draft-ietf-ccamp-lsp-diversity-05.txt

             This field is allowed in the Diversity XRO subobject. However,
      multiple reserved. It SHOULD be set to zero on
             transmission, and MUST be ignored on receipt.

        IPv4 Diversity XRO subobjects Identifier source address:

            This field is set to the IPv4 address of the node that
            assigns the diversity identifier. Depending on the
            diversity identifier type, the diversity identifier source
            may be present a client node, PCE entity or network node.
            Specifically:

           o  When the diversity identifier type is set to "IPv4 Client
              Initiated Identifier", the value is set to IPv4 tunnel
              sender address of the reference LSP against which
              diversity is desired. IPv4 tunnel sender address is as
              defined in [RFC3209].

           o  When the diversity identifier type is set to "IPv4 PCE
              Allocated Identifier", the value indicates the IPv4
              address of the node that assigned the Path Key identifier
              and that can return an XRO. expansion of the Path Key or use
              the Path Key as exclusion in a path computation. The Path
              Key is defined in [RFC5553].

           o  When the diversity identifier type is set to "IPv4
              Network Assigned Identifier", the value indicates the IPv4
              address of the node publishing the Path Affinity Set
              (PAS).

        Diversity Identifier Value:

            Encoding for this field depends on the diversity identifier
            type, as defined in the following.

            When the diversity identifier type is set to "IPv4 Client
            Initiated Identifier", the diversity identifier value is
            encoded as follows:

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

       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             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+                 IPv4 tunnel end point address                 |                             Value
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |
      //                                                             //          Must Be Zero         |     Tunnel ID                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Types (2 bytes): This document defines the following types of
      TLVs:

         -  Type = 1: IPv4 Point-to-Point tunnel identifier.

         -  Type = 2: IPv6 Point-to-Point tunnel identifier.

         -  Type = 3: IPv4 Path Key.

         -  Type = 4: IPv6 Path Key.

         -  Type = 5: IPv4 Path Affinity Set (PAS).

         -  Type = 6: IPv6 Path Affinity Set (PAS).

      Format of the individual TLVs is described in the following.

   2.1.1.
      |                       Extended Tunnel identifier TLVs ID                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          Must Be Zero         |            LSP ID             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

            The IPv4 and IPv6 Point-to-Point (P2P) tunnel identifier TLVs for
      diversity XRO subobjects end point address, Tunnel ID, Extended
            Tunnel ID and LSP ID are defined as follows.

   2.1.1.1. IPv4 Point-to-Point tunnel defined in [RFC3209].

            When the diversity identifier TLV type is set to "IPv4 PCE
            Allocated Identifier", the diversity identifier value is
            encoded as follows:

       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 = 1            |          Length = 24          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                 IPv4 tunnel end point address                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      |          Must Be Zero         |     Tunnel ID                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       Extended Tunnel ID                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   IPv4 tunnel sender address                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         Must Be Zero          |            LSP ID           Path Key            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Type:

             IPv4 Point-to-Point tunnel identifier TLV (to be assigned
             by IANA; suggested value: 1).

        Length:

            The length contains the total length of the TLV in bytes,
            including the type and length fields.

            The length Path Key is always
            24.

        The remaining fields are as defined in [RFC3209].

         Please note that the L-bit, exclusion and attribute flags
         defined at [RFC5553].

            When the diversity XRO subobject level in Section 2.1
         are equally applicable identifier type is set to "IPv4 Network
            Assigned Identifier", the IPv4 Point-to-Point tunnel
         identifier TLV.

   2.1.1.2. IPv6 Point-to-Point tunnel diversity identifier TLV value is
            encoded as follows:

       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 = 2            |          Length = 60          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                 IPv6 tunnel end point address             Path Affinity Set (PAS) identifier                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             IPv6 tunnel end point address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             IPv6 tunnel end point address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             IPv6 tunnel end point address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          Must Be Zero         |     Tunnel ID                 |

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       Extended Tunnel ID                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   Extended Tunnel ID (cont.)                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   Extended Tunnel ID (cont.)                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   Extended Tunnel ID (cont.)                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   IPv6 tunnel sender address                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |               IPv6 tunnel sender address (cont.)              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |               IPv6 tunnel sender address (cont.)              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |               IPv6 tunnel sender address (cont.)              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          Must Be Zero         |            LSP ID             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Type:

             IPv6 Point-to-Point tunnel identifier TLV (to be assigned
             by IANA; suggested value: 2).

        Length:

             The length contains the total length of the TLV in bytes,
            including Path affinity Set (PAS) identifier is a single number
             that represents a summarized SRLG for the type and length fields. The length reference path
             against which diversity is always
            60. desired. The remaining fields are as defined in [RFC3209].

         Please note that node identified by
             the L-bit, exclusion and attribute flags
         defined at "IPv4 Diversity Identifier source address" field of
             the diversity XRO subobject level in Section 2.1
         are equally applicable to assigns the IPv6 Point-to-Point tunnel
         identifier TLV. PAS value.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

   2.1.2. Path Key TLVs

      The IPv4 and IPv6 Path Key TLVs for diversity Diversity XRO subobjects are
      defined as follows.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

   2.1.2.1. IPv4 Path Key TLV Subobject

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |
      |L|  XRO Type = 3   |     Length = 12    |DI Type|A-Flags|E-Flags| Resvd |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         Must Be Zero           IPv6 Diversity Identifier source address            |           Path Key
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         IPv6 Diversity Identifier source address (cont.)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        PCE ID (4 bytes)         IPv6 Diversity Identifier source address (cont.)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Type:

             IPv4 Path Key TLV (to be assigned by IANA; suggested
             value: 3).

        Length:

            The length contains the total length of the TLV in bytes,
            including the type and length fields.
      |         IPv6 Diversity Identifier source address (cont.)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  Diversity Identifier Value                   |
      //                            ...                              //
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        L:
             The length is always
            12.

        Path Key:

            Path Key L-flag is used as for the XRO subobjects defined in [RFC5553].

         PCE-ID:

            The IPv4 address of a node
             [RFC4874], i.e.,

             0 indicates that assigned the Path Key
            identifier and attribute specified MUST be excluded.

             1 indicates that can return an expansion of the Path Key
            or use the Path Key as exclusion in a path computation.

         Please note that exclusion and attribute flags defined at the specified SHOULD be avoided.

        XRO Type

             Type for IPv6 diversity XRO subobject level in Section 2.1 are equally
         applicable to the IPv4 Path Key TLV.

   2.1.2.2. IPv6 Path Key TLV

        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 = 4            |          Length = 24          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      |          Must Be Zero         |           Path Key            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        PCE ID (16 bytes)                      |
      |                                                               |
      |                                                               |
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Type:

             IPv4 Path Key TLV (to be assigned by
             IANA; suggested value: 4).

        Length: 38).

        Length

             The length Length contains the total length of the TLV subobject in
             bytes, including the type Type and length Length fields. The length is always
            24.

        Path Key:

            Path Key Length is defined in [RFC5553].

         PCE-ID:

            The IPv6 address of a node that assigned
             variable, depending on the Path Key diversity identifier and that can return an expansion of the Path Key
            or use the Path Key as exclusion in a path computation.

         Please note that the L-bit, exclusion and attribute flags value.

        Attribute Flags (A-Flags):

             As defined at the diversity XRO subobject level in Section 2.1
         are equally applicable 2.1.1 for the IPv4 counterpart.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

        Exclusion Flags (E-Flags):

             As defined in Section 2.1.1 for the IPv4 counterpart.

        Resvd

             This field is reserved. It SHOULD be set to zero on
             transmission, and MUST be ignored on receipt.

        Diversity Identifier Type (DI Type)

             This field is defined in the IPv6 Path Key TLV.

   2.1.3. Path Affinity Set TLVs

      The same fashion as its IPv4
             counter part described in Section 2.1.1.
             The DI Types associated with IPv6 addresses are defined,
             as follows:

             IPv6 Client Initiated Identifier   4 (to be assigned by
             IANA)
             IPv6 PCE Allocated Identifier      5 (to be assigned by
             IANA)
             IPv6 Network Assigned Identifier   6 (to be assigned by
             IANA)

             These idenifier are assigned and used as defined in
             Section 2.1.1.

        IPv4 Diversity Identifier source address:

            This field is set to IPv6 Path Affinity Set (PAS) TLVs address of the node that assigns
            the diversity identifier. How identity of node for various
            diversity XRO
      subobjects are defined types is determined is as follows.

   2.1.3.1. described in Section
            2.1.1 for the IPv4 PAS TLV counterpart.

        Diversity Identifier Value:

            Encoding for this field depends on the diversity identifier
            type, as defined in the following.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

            When the diversity identifier type is set to "IPv6 Client
            Initiated Identifier", the diversity identifier value is
            encoded as follows:

       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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt
      |           Type = 5                 IPv6 tunnel end point address                 |          Length = 16
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             IPv6 tunnel end point address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   Path Affinity Set identifier             IPv6 tunnel end point address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   IPv4 Path Source Address             IPv6 tunnel end point address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                 IPv4 Path Destination Address          Must Be Zero         |     Tunnel ID                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                       Extended Tunnel ID                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   Extended Tunnel ID (cont.)                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   Extended Tunnel ID (cont.)                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   Extended Tunnel ID (cont.)                  |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |          Must Be Zero         |            LSP ID             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Type:

             IPv4 PAS TLV (to be assigned by IANA; suggested value: 5).

        Length:

            The length contains the total length of the TLV in bytes,
            including the type and length fields. The length is always
            16.

        Path Affinity Set identifier:
            The Path affinity Set identifier (4 bytes) is a single
            number that represents a summarized SRLG for this path.

        IPv4 Path Source Address:

            The IPv4 address of the source node associated with the
            Path.

        IPv4 Path Destination Address:

            The IPv4 address of the destination node associated with
            the Path.

         Please note that L-bit, exclusion IPv6 tunnel end point address, Tunnel ID, IPv6 Extended
            Tunnel ID and attribute flags LSP ID are as defined
         at in [RFC3209].

            When the diversity XRO subobject level in Section 2.1 are
         equally applicable identifier type is set to "IPv6 PCE
            Allocated Identifier", the IPv4 PAS TLV.

   2.1.3.2. IPv6 PAS TLV diversity identifier value is
            encoded as follows:

       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

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |           Type = 6            |          Length = 40          |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                   Path Affinity Set identifier                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+         Must Be Zero          |                   IPv6           Path Source Address Key            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                 IPv6

            The Path Source Address (cont.)              | Key is defined in [RFC5553].

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

            When the diversity identifier type is set to "IPv6 Network
            Assigned Identifier", the diversity identifier value is
            encoded as follows:

        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             Path Source Address (cont.) Affinity Set (PAS) identifier                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                 IPv6

             The Path Source Address (cont.)              |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      | affinity Set (PAS) identifier is as defined in
             Section 2.1.1.

   2.2. Processing rules for the Diversity XRO subobject

      The procedure defined in [RFC4874] for processing XRO and EXRS is
      not changed by this document. If the processing node cannot
      recognize the IPv4/ IPv6 Path Destination Address                 |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             IPv6 Path Destination Address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             IPv6 Path Destination Address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |             IPv6 Path Destination Address (cont.)             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

        Type:

             IPv6 PAS TLV (to be assigned by IANA; suggested value: 6).

        Length:

            The length contains the total length of the TLV in bytes,
            including the type and length fields. The length is always
            40.

        Path Affinity Set identifier:
            The Path affinity Set identifier (4 bytes) is a single
            number that represents a summarized SRLG for this path.

        IPv6 Path Source Address:

            The IPv6 address of the source node associated with the
            Path.

        IPv6 Path Destination Address:

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

            The IPv6 address of the destination node associated with
            the Path.

         Please note that the L-bit, exclusion and attribute flags
         defined at the diversity XRO subobject level in Section 2.1
         are equally applicable to the IPv6 PAS TLV.

   2.2. Processing rules for the Diversity XRO subobject

      The procedure defined in [RFC4874] for processing XRO and EXRS is
      not changed by this document.

      If subobject, the processing node cannot recognize the Diversity XRO
      subobject or the TLV contained in it, is
      expected to follow the node follows procedure defined in [RFC4874].

      An XRO object MAY contain multiple Diversity subobjects. E.g., In
      order to exclude multiple Path Keys, an EN may include multiple
      Diversity XRO subobjects each with a different Path Key.
      Similarly, in order to exclude multiple PAS identifiers, an EN
      may include multiple Diversity XRO subobjects each with a
      different PAS identifier. However, all Diversity subobjects are expected to in an
      XRO SHOULD contain the same TLV
      type. Diversity Identifier Type. If a Path
      message contains an XRO with Diversity subobjects with TLVs of different types, multiple
      Diversity Identifier Types, the processing node SHOULD return a
      PathErr with the error code "Routing Problem" (24) and error sub-
      code "XRO Too Complex" (68). If the processing node is the
      destination for the LSP being signaled, it SHOULD NOT process a
      Diversity XRO subobject.

      The attribute-flags affect the processing of the Diversity XRO
      subobject as follows:

           o  When the "destination node exception" flag is not set, the
             exclusion flags SHOULD also be respected ignored for the destination node.

           o When the "processing node exception" flag is not set, the
             exclusion flags SHOULD also be respected ignored for the processing node. The
             processing node is the node performing path calculation.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

           o  When the "penultimate node exception" flag is not set, the
             exclusion flags SHOULD also be respected ignored for the penultimate node. node on
             the path of the LSP being established.

           o  The use of "LSP ID to be ignored" flag is only defined for the IPv4 and
             "IPv4/ IPv6 tunnel identifier TLVs. This flag is
             never set and is always ignored in processing all other
             TLVs. Client Initiated Identifier" diversity types.
             When the "LSP ID Diversity Identifier Type is set to be ignored" any other
             value, this flag is set, the
             processing node MUST calculate a path based SHOULD NOT be set on exclusions

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

             from the paths of all known LSPs matching the tunnel-id,
             source, destination transmission and extended tunnel-id specified
             MUST be ignored in
             the subobject (i.e., tunnel level exclusion). processing. When this flag is not set,
             the lsp-id is not ignored and the exclusion applies only
             to the specified LSP (i.e., LSP level exclusion).

      The rest

      If the L-flag of the diversity XRO subobject is not set, the
      processing role depends on node proceeds as follows.

      -  "IPv4/ IPv6 Client Initiated Identifiers" Diversity Type:  the
         processing node MUST ensure that any path calculated for the
         signaled LSP is diverse from the TLV carried RSVP TE FEC identified by the
      object.

   2.2.1. Processing rules for
         client in the XRO subobject.

      -  "IPv4/ IPv6 PCE Allocated Identifiers" Diversity Type: the tunnel identifier TLVs

      This section describes
         processing rules node MUST ensure that any path calculated for the IPv4 and IPv6
      tunnel identifier TLVs.

      If
         signaled LSP is diverse from the L-flag of route identified by the Path-
         Key. The processing node MAY use the PCE identified by the IPv4
         Diversity Identifier source address in the diversity XRO subobject is not set, for route
         computation. The processing node MAY use the Path-Key
         resolution mechanisms described in [RFC5553].

      -   "IPv4/ IPv6 Network Assigned Identifiers" Diversity Type: the
         processing node follows MUST ensure that the following procedure: path calculated for the
         signaled LSP respects the requested PAS exclusion. .

      -  The  Regardless of whether the path computation is performed
         locally or at a remote node (e.g., PCE), the processing node
         MUST ensure that any path calculated for the signaled LSP
         respects the requested exclusion flags with respect to the
         excluded path referenced by the subobject, including local
         resources.

      -  If the processing node fails to find a excluded path that meets the
         requested constraint, referenced in the processing node MUST return a PathErr
         with the error code "Routing Problem" (24) and error sub-code
         "Route blocked by Exclude Route" (67).

      -  If the excluded path referenced in the tunnel identifier TLV XRO subobject is
         unknown to the processing node, the processing node SHOULD
         ignore the tunnel identifier TLV in the diversity XRO subobject
         of XRO and SHOULD proceed with the
         signaling request. After sending the Resv for the signaled LSP,
         the processing node SHOULD return a PathErr with the error code
         "Notify Error" (25) and error sub-code "Route of reference in
         diversity XRO tunnel identifier unknown" (value to be assigned by
         IANA, suggested value: 13) for the signaled LSP.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      -  If the processing node fails to find a path that meets the
         requested constraint, the processing node MUST return a PathErr
         with the error code "Routing Problem" (24) and error sub-code
         "Route blocked by Exclude Route" (67).

      If the L-flag of the diversity XRO subobject is set, the
      processing node follows proceeds as follows:

      -  "IPv4/ IPv6 Client Initiated Identifiers" Diversity Type:  the procedure below:
         processing node SHOULD ensure that the path calculated for the
         signaled LSP is diverse from the RSVP TE FEC identified by the
         client in the XRO subobject.

      -  "IPv4/ IPv6 PCE Allocated Identifiers" Diversity Type: the
         processing node SHOULD ensure that the path calculated for the
         signaled LSP is diverse from the route identified by the Path-
         Key.

         "IPv4/ IPv6 Network Assigned Identifiers" Diversity Type: the
         processing node SHOULD ensure that the path calculated for the
         signaled LSP respects the requested PAS exclusion. The means by
         which the processing node determines the path corresponding to
         the PAS is beyond the scope of this document.

      -  The processing node SHOULD respect the requested exclusion
         flags with respect to the excluded path to the extent possible.

      -  If the processing node fails to find a path that meets the
         requested constraint, it SHOULD proceed with signaling using a
         suitable path that meets the constraint as far as possible.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt
         After sending the Resv for the signaled LSP, it SHOULD return a
         PathErr message with error code "Notify Error" (25) and error
         sub-code "Failed to respect Exclude Route" (value: to be
         assigned by IANA, suggest value: 14) to the source node.

      -  If

      If, subsequent to the initial signaling of a diverse LSP:

      -   An excluded path referenced in the tunnel identifier TLV
         is unknown XRO subobject becomes
         known to the processing node, the processing node SHOULD
         ignore the tunnel identifier TLV or a change in the diversity XRO subobject
         of XRO and SHOULD proceed with the signaling request. After
         sending excluded path
         becomes known to the Resv for signaled LSP, processing node, the processing node
         SHOULD
         return a PathErr message with the error code "Notify Error"
         (25) and error sub-code "Route of XRO tunnel identifier
         unknown" for the signaled LSP.

      If, subsequent to the initial signaling of a diverse LSP:

      -   An excluded path referenced in the diverse LSP's XRO tunnel
         identifier becomes known to the processing node (e.g. when the
         excluded path is signaled), or

      -   A change in the excluded path becomes known to the processing
         node, the processing node SHOULD re-evaluate re-evaluate the exclusion and diversity constraints
         requested by the diverse LSP to determine whether they are
         still satisfied.

      -  If the requested exclusion constraints for the diverse LSP are
         no longer satisfied and an alternative path for the diverse LSP
         that can satisfy those constraints exists, the processing
         node SHOULD send a PathErr message for the diverse LSP with the
         error code "Notify Error" (25) and a new error sub-code
         "compliant path exists" (value: to be assigned by IANA, suggest
         value: 15). A source node receiving a PathErr message with this
         error code and sub-code combination MAY try to reoptimize the
         diverse tunnel to the new compliant path.

      -   If the requested exclusion constraints for the diverse LSP
         are no longer satisfied and no alternative path for the diverse
         LSP that can satisfy those constraints exists, then:

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

           o If the L-flag was not set in the original exclusion, the
              processing node MUST send a PathErr message for the
              diverse LSP with the error code "Routing Problem" (24) and
              error sub-code "Route blocked by Exclude Route" (67). The
              PSR flag SHOULD NOT be set. A source node receiving a
              PathErr message with this error code and sub-code
              combination SHOULD take appropriate actions to migrate the
              compliant path.

           o If the L-flag was set in the original exclusion, the
              processing node SHOULD send a PathErr message for the

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt
              diverse LSP with the error code error code "Notify Error" (25) and a
              new error sub-code "Failed to respect Exclude Route" "compliant path exists" (value: to be
              assigned by IANA, suggest value: 14). 15). The following rules apply whether or not the L-flag is set:

      - PSR flag SHOULD
              NOT be set. A source node receiving a PathErr message with the error code
         "Notify Error" (25) and error sub-codes "Route of XRO tunnel
         identifier unknown" or "Failed to respect Exclude Route" MAY
         take no action.

   2.2.2. Processing rules for the Path Key TLVs

      This section describes processing rules for the IPv4 and IPv6
      Path Key TLVs.

      An EN may include a path-key identifier (PKS) in the path-key
      TLVs of the diversity XRO subobject to convey diversity
      constraints. In order to exclude multiple PKS, an EN may include
      multiple diversity XRO subobjects each with a different path-key.

      If the node, receiving the path-key TLV, cannot recognize the
      subobject, it will react according to [RFC4874] and SHOULD ignore
      the constraint. Otherwise, if it decodes the path-key TLV but
      cannot find a route/route segment meeting the constraint:

           -if L flag is set to 0, it will react according to [RFC4874]
           and SHOULD send a PathErr message with the error code
           "Routing Problem" (24) and the error sub-code "Route blocked
           by Exclude Route" (67).

           -if L flag is set to 1, which means the node SHOULD try to
           be as much diversified as possible with the specified
           resource. If it cannot fully support the constraint, it
           SHOULD send a PathErr message with the error code/value
           combination "Notify Error" / "Failed to respect Exclude
           Route" (value: to be assigned by IANA, suggest value: 14).

      The following rules apply whether or not the L-flag is set:

      -  A source node receiving a PathErr message with the error code
         "Notify Error" (25) and error sub-codes "Failed to respect
         Exclude Route" MAY take no action.

      This mechanism can work with all the PKS resolution mechanisms,
      as detailed in [RFC5553] section 3.1. A PCE, co-located or not,
      may be used to resolve the PKS, but the node (i.e., a Label

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      Switcher Router (LSR)) can also use the PKS information to index
      a Path Segment previously supplied to it by the entity that
      originated the PKS, for example the LSR that inserted the PKS in
      the RRO or a management system.

   2.2.3. Processing rules for the PAS TLVs

      This section describes processing rules for the IPv4 and IPv6 PAS
      TLVs.

      An EN may include a PAS identifier in the PAS TLVs of the
      diversity XRO subobject to convey diversity constraints. In order
      to exclude multiple PAS identifiers, an EN may include multiple
      diversity XRO subobjects each with a different PAS identifier.

      How an EN determines the PAS identifier is a local matter for the
      EN administrator. This identifier is a suggested identifier and
      may be overridden by a CN under some conditions, regardless if L
      bit is set or not. For example, a PAS identifier can be used with
      no prior exchange of PAS information between the EN and the CN.
      Upon reception of the PAS identifier information the CN can infer
      the EN's requirements.  The actual PAS identifier used will be
      returned in the RESV message.

      If the L-flag of the diversity XRO subobject is not set, the
      processing node follows the following procedure:

      -  The processing node MUST ensure that any path calculated for
         the signaled LSP respects the requested PAS exclusion,
         including local resources.

      -  If the processing node fails to find a path that meets the
         requested constraint, the processing node MUST return a PathErr
         with the error code "Routing Problem" (24) and error sub-code
         "Route blocked by Exclude Route" (67).

      -  If the PAS value referenced in the PAS TLV is unknown to the
         processing node, the processing node MAY infer the diversity
         requirement. After sending the Resv for the signaled LSP, the
         processing node SHOULD return a PathErr with the error code
         "Notify Error" (25) and error sub-code "XRO PAS value inferred"
         (value to be assigned by IANA, suggested value: TBD). However,
         if processing node fails to infer the diversity requirement
         from PAS value, it MUST return a PathErr with the error code
         "Routing Problem" (24) and error sub-code "Route blocked by
         Exclude Route" (67).

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      If the L-flag of the diversity XRO subobject is set, the
      processing node follows the procedure below:

      -  The processing node SHOULD ensure that any path calculated for
         the signaled LSP respects the requested PAS exclusion,
         including local resources.

      -  If the processing node fails to find a path that meets the
         requested constraint, it SHOULD proceed with signaling using a
         suitable path that meets the constraint as far as possible.
         After sending the Resv for the signaled LSP, it SHOULD return a
         PathErr message with error code "Notify Error" (25) and error
         sub-code "Failed to respect Exclude Route" (value: to be
         assigned by IANA, suggest value: 14) to the source node.

      -  If the PAS value referenced in the PAS TLV is unknown to the
         processing node, the processing node MAY infer the diversity
         requirement. However, if processing node fails to infer the
         diversity requirement it MAY ignore the PAS TLV in the
         diversity XRO subobject of XRO and SHOULD proceed with the
         signaling request. After sending the Resv for signaled LSP, the
         processing node SHOULD return a PathErr message with the error
         code "Notify Error" (25) and error sub-code "Failed to respect
         Exclude Route" (value: to be assigned by IANA, suggest value:
         14) to the source node.

      In the context of VPN, upon reception of the PAS identifier
      information, the CN looks up the CN based addresses in the
      Provider Index Table (PIT). The CN also looks up the SRLG
      information (or equivalent) in the core network that is
      associated with LSPs belonging to the same Path Affinity Set and
      exclude those resources from the path computation for this LSP.
      The CN may alternatively choose from an existing path with a
      disjoint set of resources.

      Optionally the EN may use a value of all zeros in the PAS
      identifier allowing the CN to select an appropriate PAS
      identifier. Also the CN may to override the PAS identifier
      allowing the CN to re-assign the identifier if required. An EN
      should not assume that the PAS identifier used for setup is the
      actual PAS identifier.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

   2.2.3.1.1. Distribution of the Path Affinity Set Information

      Information about TE link SRLGs is already available in the IGP
      TE database. A core network can be designed to have additional
      opaque records for core network paths that distribute EN paths,
      PAS values associated with them and SRLG on a VPN basis. When a
      core network path is setup, the following information allows a CN
      to lookup the CN diversity information:

      .  L1 VPN Identifier

      .  Path Affinity Set Identifier

      .  Source CN Address

      .  Destination CN Address

      .  List of core network SRLGs (variable)

      The source CN address and destination CN address are the same
      addresses in the VPN PIT
              this error code and correspond sub-code combination MAY signal a new
              LSP to migrate the respective EN
      address identifiers.

      Note that all of compliant path.

      -  If the information is local to requested exclusion constraints for the CN context diverse LSP are
         no longer satisfied and
      is no alternative path for the diverse LSP
         that can satisfy those constraints exists, then:

           o If the L-flag was not shared with set in the EN. The VPN Identifier is associated original exclusion, the
              processing node MUST send a PathErr message for the
              diverse LSP with
      an EN. the error code "Routing Problem" (24) and
              error sub-code "Route blocked by Exclude Route" (67). The only value that is signaled from
              PSR flag SHOULD be set.

           o If the EN is L-flag was set in the Path
      Affinity Set and optionally original exclusion, the addresses of an existing LSP. The
      CN stores source and destination CN addresses of
              processing node SHOULD send a PathErr message for the
              diverse LSP in their
      native format along with the SRLG information. This information
      is internal error code error code "Notify Error"
              (25) and error sub-code "Failed to respect Exclude Route"
              (value: to be assigned by IANA, suggest value: 14). The
              PSR flag SHOULD NOT be set.

      The following rules apply whether or not the core network and L-flag is assumed set:

      -  A source node receiving a PathErr message with the error code
         "Notify Error" (25) and error sub-codes "Route of XRO tunnel
         identifier unknown" or "Failed to be known. respect Exclude Route" MAY
         take no action.

   2.3. Diversity EXRS Subobject

      [RFC4874] defines the EXRS ERO subobject. An EXRS is used to
      identify abstract nodes or resources that must not or should not
      be used on the path between two inclusive abstract nodes or

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      resources in the explicit route. An EXRS contains one or more
      subobjects of its own, called EXRS subobjects [RFC4874].

      An EXRS MAY include Diversity subobject as specified in this
      document. In this case, subobject as specified in this
      document. In this case, the IPv4 EXRS format is as follows:

      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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |L|    Type     |     Length    |           Reserved            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |L|  XRO Type   |     Length    |DI Type|A-Flags|E-Flags| Resvd |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |           IPv4 Diversity Identifier source address            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  Diversity Identifier Value                   |
      //                            ...                              //
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

      Similarly, the IPv6 EXRS format would be is as follows:

      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
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |L|    Type     |     Length    |           Reserved            |

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |L|  XRO Type     |Attribute Flags|Exclusion Flags|    Reserved   |     Length    |DI Type|A-Flags|E-Flags| Resvd |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                            TLVs ...           IPv6 Diversity Identifier source address            |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         IPv6 Diversity Identifier source address (cont.)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         IPv6 Diversity Identifier source address (cont.)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |         IPv6 Diversity Identifier source address (cont.)      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                  Diversity Identifier Value                   |
      //                            ...                              //
      |                                                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      The meanings of respective fields in EXRS header are as defined
      in [RFC4874]. The meanings of respective fields in the Diversity
      subobject are as defined earlier in this document. document for the XRO
      subobject.

      The processing rules for the EXRS object are unchanged from
      [RFC4874]. When the EXRS contains one or more Diversity
      subobject(s), the processing rules specified in Section 2.3 2.2 apply
      to the node processing the ERO with the EXRS subobject.

      If a loose-hop expansion results in the creation of another
      loose-hop in the outgoing ERO, the processing node MAY include
      the EXRS in the newly created loose hop for further processing by
      downstream nodes.

      The processing node exception for the EXRS subobject applies to
      the node processing the ERO.

      The destination node exception for the EXRS subobject applies to
      the explicit node identified by the ERO subobject that identifies
      the next abstract node. This flag is only processed if the L bit
      is set in the ERO subobject that identifies the next abstract
      node.

      The penultimate node exception for the EXRS subobject applies to
      the node before the explicit node identified by the ERO subobject
      that identifies the next abstract node. This flag is only
      processed if the L bit is set in the ERO subobject that
      identifies the next abstract node.

   3. Security Considerations

      This document does not introduce any additional security issues
      above those identified in [RFC5920], [RFC2205], [RFC3209],
      [RFC3473] and [RFC4874].

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

   4. IANA Considerations

   4.1. New XRO subobject types

      IANA registry: RSVP PARAMETERS
      Subsection: Class Names, Class Numbers, and Class Types

      This document introduces two new subobjects for the EXCLUDE_ROUTE
      object [RFC4874], C-Type 1.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      Subobject Description                Subobject Type
      --------------                       ---------------------
      IPv4 Diversity subobject             To be assigned by IANA
                                          (suggested value: 37)
      IPv6 Diversity subobject             To be assigned by IANA
                                          (suggested value: 36) 38)

   4.2. New EXRS subobject types

      The diversity XRO subobjects are also defined as new EXRS
      subobjects.

   4.3. TLV types for Diversity XRO and EXRS subobjects

      The following TLV types for Diversity XRO and EXRS subobjects are
      defined.

      TLV Description                         TLV Type
      ---------------                         --------

      IPv4 Point-to-Point tunnel identifier    To be assigned by IANA
                                             (suggested value: 1)
      IPv6 Point-to-Point tunnel identifier    To be assigned by IANA
                                             (suggested value: 2)
      IPv4 Path Key                           To be assigned by IANA
                                             (suggested value: 3)
      IPv6 Path Key                           To be assigned by IANA
                                             (suggested value: 4)
      IPv4 Path Affinity Set                                                To be assigned by IANA
                                             (suggested value: 5)
      IPv6 Path Affinity Set                                                To be assigned by IANA
                                             (suggested value: 6)

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

   4.4. New RSVP error sub-codes

      IANA registry: RSVP PARAMETERS
      Subsection: Error Codes and Globally Defined Error Value Sub-
      Codes

      For Error Code "Notify Error" (25) (see [RFC3209]) the following
      sub-codes are defined.

         Sub-code                            Value
         --------                            -----

         Route of XRO                        To be assigned by IANA.
         tunnel identifier unknown           Suggested Value: 13.

         Failed to respect Exclude Route     To be assigned by IANA.
                                             Suggested Value: 14.

         Compliant path exists               To be assigned by IANA.
                                             Suggested Value: 15.

         XRO PAS value inferred              To be assigned by IANA.
                                             Suggested Value: 16

   5. Acknowledgements

      The authors would like to thank Luyuan Fang and Walid Wakim for
      their review comments.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

   6. References

   6.1. Normative References

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

      [RFC3209] Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan,
                V., and G. Swallow, "RSVP-TE: Extensions to RSVP for
                LSP Tunnels", RFC 3209, December 2001.

      [RFC3473] Berger, L., "Generalized Multi-Protocol Label Switching
                (GMPLS) Signaling Resource ReserVation Protocol-Traffic
                Engineering (RSVP-TE) Extensions", RFC 3473, January
                2003.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      [RFC4874] Lee, CY., Farrel, A., and S. De Cnodder, "Exclude
                Routes - Extension to Resource ReserVation Protocol-
                Traffic Engineering (RSVP-TE)", RFC 4874, April 2007.

      [RFC5553]   Farrel, A., Ed., Bradford, R., and JP. Vasseur,
      "Resource Reservation Protocol (RSVP) Extensions for Path Key
      Support", RFC 5553, May 2009.

   6.2. Informative References

      [RFC4208] Swallow, G., Drake, J., Ishimatsu, H., and Y. Rekhter,
                "Generalized Multiprotocol Label Switching (GMPLS)
                User-Network Interface (UNI): Resource ReserVation
                Protocol-Traffic Engineering (RSVP-TE) Support for the
                Overlay Model", RFC 4208, October 2005.

      [RFC4920] Farrel, A., Ed., Satyanarayana, A., Iwata, A., Fujita,
                N., and G. Ash, "Crankback Signaling Extensions for
                MPLS and GMPLS RSVP-TE", RFC 4920, July 2007.

      [RFC5520]   Bradford, R., Ed., Vasseur, JP., and A. Farrel,
                "Preserving Topology Confidentiality in Inter-Domain
                Path Computation Using a Path-Key-Based Mechanism", RFC
                5520, April 2009.

      [DRAFT-SRLG-RECORDING] F. Zhang, D. Li, O. Gonzalez de Dios, C.
                Margaria, "RSVP-TE Extensions for Collecting SRLG
                Information", draft-ietf-ccamp-rsvp-te-srlg-collect.txt,
                work in progress.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-05.txt

      [RFC2205] Braden, R. (Ed.), Zhang, L., Berson, S., Herzog, S. and
                S. Jamin, "Resource ReserVation Protocol -- Version 1
                Functional Specification", RFC 2205, September 1997.

      [RFC4026] Andersson, L. and T. Madsen, "Provider Provisioned
                Virtual Private Network (VPN) Terminology", RFC 4026,
                March 2005.

      [RFC5253] Takeda, T., Ed., "Applicability Statement for Layer 1
                Virtual Private Network (L1VPN) Basic Mode", RFC 5253,
                July 2008.

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt

      [RFC5920] Fang, L., Ed., "Security Framework for MPLS and GMPLS
                Networks", RFC 5920, July 2010.

   Contributor's

   Contributors' Addresses

      Igor Bryskin
      ADVA Optical Networking
      Email: ibryskin@advaoptical.com

      Daniele Ceccarelli
      Ericsson
      Email: Daniele.Ceccarelli@ericsson.com

      Dhruv Dhody
      Huawei Technologies
      EMail: dhruv.ietf@gmail.com

      Oscar Gonzalez de Dios
      Telefonica I+D
      Email: ogondio@tid.es

      Don Fedyk
      Hewlett-Packard
      Email: don.fedyk@hp.com

      Clarence Filsfils
      Cisco Systems, Inc.
      Email: cfilsfil@cisco.com

      Xihua Fu
      ZTE
      Email: fu.xihua@zte.com.cn

   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt      draft-ietf-ccamp-lsp-diversity-05.txt

      Email: fu.xihua@zte.com.cn

      Gabriele Maria Galimberti
      Cisco Systems
      Email: ggalimbe@cisco.com

      Ori Gerstel
      SDN Solutions Ltd.
      Email: origerstel@gmail.com

      Matt Hartley
      Cisco Systems
      Email: mhartley@cisco.com

      Kenji Kumaki
      KDDI Corporation
      Email: ke-kumaki@kddi.com

      Rudiger Kunze
      Deutsche Telekom AG
      Email: Ruediger.Kunze@telekom.de

      Lieven Levrau
      Alcatel-Lucent
      Email: Lieven.Levrau@alcatel-lucent.com

      Cyril Margaria
      cyril.margaria@gmail.com

      Julien Meuric
      France Telecom Orange
      Email: julien.meuric@orange.com

      Yuji Tochio
      Fujitsu
      Email: tochio@jp.fujitsu.com

      Xian Zhang
      Huawei Technologies
      Email: zhang.xian@huawei.com

   Authors' Addresses
   Internet Draft      draft-ietf-ccamp-lsp-diversity-04.txt      draft-ietf-ccamp-lsp-diversity-05.txt

      Zafar Ali
      Cisco Systems.
      Email: zali@cisco.com

      Dieter Beller
      Alcatel-Lucent
      Email: Dieter.Beller@alcatel-lucent.com

      George Swallow
      Cisco Systems
      Email: swallow@cisco.com

      Fatai Zhang
      Huawei Technologies
      Email: zhangfatai@huawei.com