Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) extension for recording TE Metric of a Label Switched Path
draft-ietf-teas-te-metric-recording-03

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Document Type Active Internet-Draft (teas WG)
Authors Zafar Ali  , George Swallow  , Clarence Filsfils  , Matt Hartley  , Kenji Kumaki  , Ruediger Kunze 
Last updated 2016-02-08
Replaces draft-ietf-ccamp-te-metric-recording
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TEAS Working Group                                        Zafar Ali 
     Internet Draft                                       George Swallow 
     Intended status: Standard Track                   Clarence Filsfils 
     Expires: August 7, 2016                                Matt Hartley  
                                                           Cisco Systems 
                                                                         
                                                            Kenji Kumaki 
                                                        KDDI Corporation 
                                                                         
                                                          Ruediger Kunze 
                                                     Deutsche Telekom AG  
                                                                         
                                                        February 8, 2016  
      
                                         
          Resource ReserVation Protocol-Traffic Engineering (RSVP-TE) 
           extension for recording TE Metric of a Label Switched Path 
                     draft-ietf-teas-te-metric-recording-03 
                                         
     Status of this Memo 

     This Internet-Draft is submitted in full conformance with the 
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     This Internet-Draft will expire on August 7, 2016.       
      
      
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     Copyright Notice 
         

     Copyright (c) 2016 IETF Trust and the persons identified as the 
     document authors.  All rights reserved. 

     This document is subject to BCP 78 and the IETF Trust's Legal 
     Provisions Relating to IETF Documents 
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     This document may contain material from IETF Documents or IETF 
     Contributions published or made publicly available before November 
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     Without obtaining an adequate license from the person(s) 
     controlling the copyright in such materials, this document may not 
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     Abstract 

     There are many scenarios in which Traffic Engineering (TE) metrics 
     such as cost, Delay and Delay variation associated with the TE link 
     formed by Label Switched Path (LSP) are not available to the 
     ingress and egress nodes. This draft provides extensions for the 
     Resource ReserVation Protocol- Traffic Engineering (RSVP-TE) to 
     support automatic collection of cost, Delay and Delay variation 
     information for the TE link formed by a LSP. 

     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 

        Copyright Notice............................................1 
        1. Introduction.............................................3 
        1.1. Use Cases..............................................4 
              1.1.1. GMPLS..........................................4 
              1.1.2. Inter-area tunnels with loose-hops.............4 
        2. RSVP-TE Requirement......................................4 
        2.1. Cost, Delay and Delay Variation Collection Indication..4 
        2.2. Cost, Delay and Delay Variation Collection.............4 
        2.3. Cost, Delay and Delay Variation Update.................5 
        2.4. Cost Definition........................................5 
        3. RSVP-TE signaling extensions.............................5 

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        3.1. Cost, Delay and Delay Variation Collection Flags.......5 
        3.2. Cost Subobject.........................................6 
        3.3. Delay Subobject........................................6 
        3.4. Delay Variation Subobject..............................7 
        4. Signaling Procedures.....................................8 
        4.1. Cost, Delay and Delay Variation Collection Request.....8 
        4.2. Cost, Delay and Delay Variation Recoding...............8 
        4.3. Metric Update..........................................10 
        4.4. Compatibility..........................................10 
        5. Endpoint processing......................................11 
        6. Manageability Considerations.............................11 
        6.1. Policy Configuration...................................11 
        7. Security Considerations..................................12 
        8. IANA Considerations......................................12 
        8.1. RSVP Attribute Bit Flags...............................12 
        8.2. Policy Control Failure Error subcodes..................13 
        9. Acknowledgments..........................................13 
        10. References..............................................14 
        10.1. Normative References..................................14 
        10.2. Informative References................................14 
         

     1. Introduction 

        In certain networks, such as financial information networks, 
        network performance information (e.g. Delay, Delay variation) is 
        becoming as critical to data path selection as other metrics RFC 
        7471 [RFC7471], [DRAFT-ISIS-TE-METRIC]. If cost, Delay or Delay 
        variation associated with a Forwarding Adjacency (FA) or a 
        Routing Adjacency (RA) LSP is not available to the ingress or 
        egress node, it cannot be advertised as an attribute of the TE 
        link (FA or RA). There are scenarios in packet and optical 
        networks where the route information of an LSP may not be 
        provided to the ingress node for confidentiality reasons and/or 
        the ingress node may not run the same routing instance as the 
        intermediate nodes traversed by the path. Similarly, there are 
        scenarios in which measuring Delay and/ or Delay variation on a 
        TE link formed by a LSP is not supported. In such scenarios, the 
        ingress node cannot determine the cost, Delay and Delay 
        variation properties of the LSP's route.  

        One possible way to address this issue is to configure cost, 
        Delay and Delay variation values manually. However, in the event 
        of an LSP being rerouted (e.g. due to re-optimization), such 
        configuration information may become invalid. Consequently, in 
        cases where that an LSP is advertised as a TE-Link, the ingress 
        and/or egress nodes cannot provide the correct Delay, Delay 
        variation and cost information associated with the TE-Link 
        automatically.  

        In summary, there is a requirement for the ingress and egress 
        nodes to learn the cost, Delay and Delay variation information 
        of the TE link formed by a LSP. This document provides a 
        mechanism to collect the cost, Delay and Delay variation 
        information of a LSP, which can then be advertised as properties 
        of the TE-link formed by that LSP.  Note that specification of 

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        the use of the collected cost, Delay and Delay variation 
        information is outside the scope of this document. 

     1.1. Use Cases 

        This section describes some of the use cases for TE metric 
        recording.  

     1.1.1. GMPLS 

        In Generalized Multi-Protocol Label Switching (GMPLS) networks 
        signaling bidirectional LSPs, the egress node cannot determine 
        the cost, Delay and Delay variation properties of the LSP path. 
        A multi-domain or multi-layer network is an example of such 
        networks. A GMPLS User-Network Interface (UNI) [RFC4208] is also 
        an example of such networks.  

     1.1.2. Inter-area tunnels with loose-hops 

        When a LSP is established over multiple IGP-areas using loose 
        hops in the ERO, the ingress node only has knowledge of the 
        first IGP-area traversed by the LSP. In this case, it cannot 
        determine the cost, Delay and Delay variation properties of the 
        LSP path. 

     2. RSVP-TE Requirement  

        This section outlines RSVP-TE requirements for the support of 
        the automatic discovery of cost, Delay and Delay variation 
        information of an LSP.  

     2.1. Cost, Delay and Delay Variation Collection Indication 

        The ingress node of the LSP SHOULD be capable of indicating 
        whether the cost and/or delay and/ or delay variation 
        information of the LSP is to be collected during the signaling 
        procedure of setting up an LSP. A separate collection indication 
        flag for each of this attribute is required. Cost, delay and 
        delay variation information SHOULD NOT be collected without an 
        explicit request for it being made by the ingress node.  

     2.2. Cost, Delay and Delay Variation Collection 

        If requested, the cost and/or delay and/ or delay variation 
        information SHOULD be collected during the setup of an LSP. Each 
        of the cost, delay or delay variation can be collected 
        independently. The endpoints of the LSP can use the collected 
        information, for example, for routing, flooding and other 
        purposes. 

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     2.3. Cost, Delay and Delay Variation Update 

        When the cost and/or delay and/ or delay variation information 
        of an existing LSP for which corresponding information was 
        collected during signaling changes, the relevant nodes of the 
        LSP SHOULD be capable of updating the associated information of 
        the LSP.  This means that the signaling procedure SHOULD be 
        capable of updating the new cost and/or delay and/ or delay 
        variation information. 

     2.4. Cost Definition 

        Although the terms Delay and Delay variation are well 
        understood, "cost" may be ambiguous; in particular, in the 
        context of a LSP that traverses nodes and links operated by 
        different entities, there may be no common definition of cost. 
        However, there are situations in which the entire LSP may be 
        within a single AS (e.g. inter-area LSPs) in which cost 
        discovery is useful. 

        The precise meaning and interpretation of numerical costs is a 
        matter for the network operator. For the purposes of this 
        document, two constraints are assumed: 

          .  A higher cost represents an inferior path.  

          .  Simple addition of costs for different sections of a path 
             must make sense. 

     3. RSVP-TE signaling extensions 

     3.1. Cost, Delay and Delay Variation Collection Flags 

        In order to indicate nodes that cost and/or Delay and/ or Delay 
        variation collection is desired, this document defines a new 
        flags in the Attribute Flags TLV (see RFC 5420 [RFC5420]), which 
        MAY be carried in an LSP_REQUIRED_ATTRIBUTES or LSP_ATTRIBUTES 
        Object: 

        - Cost Collection flag (Bit number to be assigned by IANA) 

        - Delay Collection flag (Bit number to be assigned by IANA) 

        - Delay Variation Collection flag (Bit number to be assigned by 
        IANA) 

        The Cost, Delay and Delay Variation Collection flag is 
        meaningful on a Path message.  If the Cost Collection flag is 
        set to 1, it means that the cost information SHOULD be reported 
        to the ingress and egress node along the setup of the LSP. 
        Similarly, if the Delay Collection flag is set to 1, it means 
        that the Delay information SHOULD be reported to the ingress and 
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        egress node along the setup of the LSP. Likewise, if the Delay 
        Variation Collection flag is set to 1, it means that the Delay 
        Variation information SHOULD be reported to the ingress and 
        egress node along the setup of the LSP. 

        The rules of the processing of the Attribute Flags TLV are not 
        changed.  

     3.2. Cost Subobject  

        This document defines a new RRO sub-object (ROUTE_RECORD sub-
        object) to record the cost information of the LSP.  Its format 
        is modeled on the RRO sub-objects defined in RFC 3209 [RFC3209]. 

         
        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     |    Reserved (must be zero)    | 
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
       |                              Cost                             | 
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
      
         
           Type: The type of the sub-object (value to be assigned by 
           IANA). 

           Length: The Length field contains the total length of the 
           sub-object in bytes, including the Type and Length fields. 
           The Length value is set to 8.  

           Reserved: This field is reserved for future use. It MUST be 
           set to 0 on transmission and MUST be ignored when received.  

           Cost: Cost of the local TE link along the route of the LSP.  

     3.3. Delay Subobject 

        This document defines a new RRO sub-object (ROUTE_RECORD sub-
        object) to record the delay information of the LSP.  Its format 
        is modeled on the RRO sub-objects defined in RFC 3209 [RFC3209].  

        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      |    Reserved (must be zero)    | 
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
       |A|  Reserved   |                      Delay                    |              
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
         

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           Type: The type of the sub-object (value to be assigned by 
           IANA). 

           Length: The Length field contains the total length of the 
           sub-object in bytes, including the Type and Length fields. 
           The Length value is set to 8. 

           A-bit: These fields represent the Anomalous (A) bit 
           associated with the Downstream and Upstream Delay 
           respectively, as defined in RFC 7471 [RFC7471]. 

           Reserved: These fields are reserved for future use. They MUST 
           be set to 0 when sent and MUST be ignored when received. 

           Delay: Delay of the local TE link along the route of the LSP, 
           encoded as 24-bit integer, as defined in RFC 7471 [RFC7471]. 
           When set to the maximum value 16,777,215 (16.777215 sec), the 
           delay is at least that value and may be larger.  

     3.4. Delay Variation Subobject 

        This document defines a new RRO sub-object (ROUTE_RECORD sub-
        object) to record the delay variation information of the LSP.  
        Its format is modeled on the RRO sub-objects defined in RFC 3209 
        [RFC3209].  
         
        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      |    Reserved (must be zero)    | 
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
       |A|  Reserved   |                 Delay Variation               |              
       +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ 
         

           Type: The type of the sub-object (value to be assigned by 
           IANA). 

           Length: The Length field contains the total length of the 
           sub-object in bytes, including the Type and Length fields. 
           The Length value is set to 8. 

           A-bit: These fields represent the Anomalous (A) bit 
           associated with the Downstream and Upstream Delay Variation 
           respectively, as defined in RFC 7471 [RFC7471]. 

           Reserved: These fields are reserved for future use. It SHOULD 
           be set to 0 when sent and MUST be ignored when received. 

           Delay Variation: Delay Variation of the local TE link along 
           the route of the LSP, encoded as 24-bit integer, as defined 
           in RFC 7471 [RFC7471]. When set to the maximum value 
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           16,777,215 (16.777215 sec), the delay variation is at least 
           that value and may be larger.  

     4. Signaling Procedures 

        The rules of the processing of the LSP_REQUIRED_ATTRIBUTES, 
        LSP_ATTRIBUTE and ROUTE_RECORD Objects are not changed. 

        As signaling procedure for cost, delay and delay variation 
        collection is similar, many parts of this section are written 
        such that they apply equally to cost, delay and delay variation 
        collection. There is also very strong similarity of these 
        procedures with SRLG recording [DRAFT-SRLG-RECORDING].  

     4.1. Cost, Delay and Delay Variation Collection Request 

        Per RFC 3209 [RFC3209], an ingress node initiates the recording 
        of the route information of an LSP by adding a RRO to a Path 
        message. If an ingress node also desires Cost and/or Delay 
        and/or Delay Variation recording, it MUST set the appropriate 
        flag(s) in the Attribute Flags TLV which MAY be carried either 
        in an LSP_REQUIRED_ATTRIBUTES Object when the collection is 
        mandatory, or in an LSP_ATTRIBUTES Object when the collection is 
        desired, but not mandatory. 

     4.2. Cost, Delay and Delay Variation Recoding 

        When a node receives a Path message which carries an 
        LSP_REQUIRED_ATTRIBUTES Object and the Cost Collection Flag set, 
        if local policy determines that the cost information is not to 
        be provided to the endpoints or the information is not known, it 
        MUST return a PathErr message with error code 2 (policy) and 
        error subcode "Cost Recording Rejected" (value to be assigned by 
        IANA) to reject the Path message. Similarly, when a node 
        receives a Path message which carries an LSP_REQUIRED_ATTRIBUTES 
        Object and the Delay Collection Flag set, if local policy 
        determines that the Delay information is not to be provided to 
        the endpoints or the information is not known, it MUST return a 
        PathErr message with error code 2 (policy) and error subcode 
        "Delay Recording Rejected" (value to be assigned by IANA) to 
        reject the Path message. Likewise, when a node receives a Path 
        message which carries an LSP_REQUIRED_ATTRIBUTES Object and the 
        Delay Variation Collection Flag set, if local policy determines 
        that the Delay Variation information is not to be provided to 
        the endpoints or the information is not known, it MUST return a 
        PathErr message with error code 2 (policy) and error subcode 
        "Delay Variation Recording Rejected" (value to be assigned by 
        IANA) to reject the Path message. 

        When a node receives a Path message which carries an 
        LSP_ATTRIBUTES Object and the Cost and/or Delay and/or Delay 
        Variation Collection Flag set, if local policy determines that 
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        the corresponding information is not to be provided to the 
        endpoints, or the information is not known, the Path message 
        SHOULD NOT be rejected due to the recording restriction and the 
        Path message SHOULD be forwarded without any Cost and/or Delay 
        and/or Delay Variation sub-object(s) in the RRO of the 
        corresponding outgoing Path message. 

        If local policy permits the recording of the Cost and/or Delay 
        and/or Delay Variation information, the processing node SHOULD 
        add corresponding information for the local TE link, as defined 
        below, to the RRO of the corresponding outgoing Path message. 
        The A-bit for the Delay MUST be set as described in RFC 7471 
        [RFC7471]. Similarly, the A-bit for the Delay Variation MUST be 
        set as described in RFC 7471 [RFC7471]. It then forwards the 
        Path message to the next node in the downstream direction. 

        If the addition of Cost and/or Delay and/or Delay Variation 
        information to the RRO would result in the RRO exceeding its 
        maximum possible size or becoming too large for the Path message 
        to contain it, the requested information MUST NOT be added. If 
        the Cost and/or Delay and/or Delay Variation collection request 
        was contained in an LSP_REQUIRED_ATTRIBUTES Object, the 
        processing node MUST behave as specified by RFC 3209 [RFC3209] 
        and drop the RRO from the Path message entirely.  If the Cost 
        and/or Delay and/or Delay Variation collection request was 
        contained in an LSP_ATTRIBUTES Object, the processing node MAY 
        omit some or all of the corresponding information from the RRO; 
        otherwise it MUST behave as specified by RFC 3209 [RFC3209] and 
        drop the RRO from the Path message entirely. 

        Following the steps described above, the intermediate nodes of 
        the LSP can collect the Cost and/or Delay and/or Delay Variation 
        information in the RRO during the processing of the Path message 
        hop by hop.  When the Path message arrives at the egress node, 
        the egress node receives the corresponding information in the 
        RRO. 

        Per RFC 3209 [RFC3209], when issuing a Resv message for a Path 
        message, which contains an RRO, an egress node initiates the RRO 
        process by adding an RRO to the outgoing Resv message.  The 
        processing for RROs contained in Resv messages then mirrors that 
        of the Path messages. 

        When a node receives a Resv message for an LSP for which Cost 
        and/or Delay and/or Delay Variation Collection is requested, 
        then when local policy allows recording of the requested 
        information, the node SHOULD add corresponding information, to 
        the RRO of the outgoing Resv message, as specified below.  The 
        A-bit for the Delay MUST be set as described in RFC 7471 
        [RFC7471]. Similarly, the A-bit for the Delay Variation MUST be 
        set as described in RFC 7471 [RFC7471]. When the Resv message 
        arrives at the ingress node, the ingress node can extract the 
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        requested information from the RRO in the same way as the egress 
        node. 

        A node MUST NOT push a Cost, Delay or Delay Variation sub-object 
        in the RECORD_ROUTE without also pushing an IPv4 sub-object, an 
        IPv6 sub-object, an Unnumbered Interface ID sub-object or a Path 
        Key sub-object. 

        Note that a link's Cost and/or Delay and/or Delay Variation 
        information for the upstream direction cannot be assumed to be 
        the same as that in the downstream. 

        .  For Path and Resv messages for a unidirectional LSP, a node 
          SHOULD include Cost and/or Delay and/or Delay Variation sub-
          objects in the RRO for the downstream data link only. 

        .  For Path and Resv messages for a bidirectional LSP, a node 
          SHOULD include Cost and/or Delay and/or Delay Variation sub-
          objects in the RRO for both the upstream data link and the 
          downstream data link from the local node.  In this case, the 
          node MUST include the information in the same order for both 
          Path messages and Resv messages.  That is, the Cost and/or 
          Delay and/or Delay Variation sub- object for the upstream link 
          is added to the RRO before the corresponding sub-object for 
          the downstream link. 

     4.3. Metric Update 

        When the Cost and/or Delay and/or Delay Variation information of 
        a link is changed, the LSPs using that link need to be aware of 
        the changes.  The procedures defined in Section 4.4.3 of RFC 
        3209 [RFC3209] MUST be used to refresh the Cost and/or Delay 
        and/or Delay Variation information if the corresponding change 
        is to be communicated to other nodes according to the local 
        node's policy.  If local policy is that the Cost and/or Delay 
        and/or Delay Variation change SHOULD be suppressed or would 
        result in no change to the previously signaled information, the 
        node SHOULD NOT send an update. 

     4.4. Compatibility 

         

        A node that does not recognize the Cost and/or Delay and/or 
        Delay Variation Collection Flag in the Attribute Flags TLV is 
        expected to proceed as specified in RFC 5420 [RFC5420].  It is 
        expected to pass the TLV on unaltered if it appears in a 
        LSP_ATTRIBUTES object, or reject the Path message with the 
        appropriate Error Code and Value if it appears in a 
        LSP_REQUIRED_ATTRIBUTES object. 

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        A node that does not recognize the Cost and/or Delay and/or 
        Delay Variation RRO sub-object is expected to behave as 
        specified in RFC 3209 [RFC3209]: unrecognized subobjects are to 
        be ignored and passed on unchanged. 

     5. Endpoint processing 

        Based on the procedures mentioned in Section 4, the endpoints 
        can get the Cost and/or Delay and/or Delay Variation information 
        automatically.  Then the endpoints can for instance advertise it 
        as a TE link to the routing instance based on the procedure 
        described in [RFC6107]. How the end point uses the collected 
        information is outside the scope of this document.  

        The ingress and egress nodes of a LSP may calculate the end-to- 
        end cost, Delay and/or Delay variation properties of the LSP 
        from the supplied values in the Resv or Path RRO respectively. 

        Typically, cost and Delay are additive metrics, but Delay 
        variation is not an additive metric. The means by which the 
        ingress and egress nodes compute the end-to-end cost, Delay and 
        Delay variation metric from information recorded in the RRO is a 
        local decision and is beyond the scope of this document. 

        Based on the local policy, the ingress and egress nodes can 
        advertise the calculated end-to-end cost, Delay and/or Delay 
        variation properties of the FA or RA LSP in TE link 
        advertisement to the routing instance based on the procedure 
        described in RFC 7471 [RFC7471], [DRAFT-ISIS-TE-METRIC]. 

        Based on the local policy, a transit node (e.g. the edge node of 
        a domain) may edit a Path or Resv RRO to remove route 
        information (e.g. node or interface identifier information) 
        before forwarding it. A node that does this SHOULD summarize the 
        cost, Delay and Delay Variation data. How a node that performs 
        the RRO edit operation calculates the cost, Delay o and/or Delay 
        variation metric is beyond the scope of this document. 

     6. Manageability Considerations 

         

     6.1. Policy Configuration 

         

        In a border node of inter-domain or inter-layer network, the 
        following Cost and/or Delay and/or Delay Variation processing 
        policy SHOULD be capable of being configured: 

         

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        o  Whether the Cost and/or Delay and/or Delay Variation of the 
        domain or specific layer network can be exposed to the nodes 
        outside the domain or layer network, or whether they SHOULD be 
        summarized, mapped to values that are comprehensible to nodes 
        outside the domain or layer network, or removed entirely. 

        A node using RFC 5553 [RFC5553] and PKS MAY apply the same 
        policy. 

     7. Security Considerations 

        This document builds on the mechanisms defined in [RFC3473], 
        which also discusses related security measures.  In addition, 
        [RFC5920] provides an overview of security vulnerabilities and 
        protection mechanisms for the GMPLS control plane.  The 
        procedures defined in this document permit the transfer of Cost 
        and/or Delay and/or Delay Variation data between layers or 
        domains during the signaling of LSPs, subject to policy at the 
        layer or domain boundary.  It is recommended that domain/layer 
        boundary policies take the implications of releasing Cost and/or 
        Delay and/or Delay Variation information into consideration and 
        behave accordingly during LSP signaling. 

     8. IANA Considerations 

     8.1. RSVP Attribute Bit Flags 

        IANA has created a registry and manages the space of the 
        Attribute bit flags of the Attribute Flags TLV, as described in 
        section 11.3 of RFC 5420 [RFC5420], in the "Attribute Flags" 
        section of the "Resource Reservation Protocol-Traffic 
        Engineering (RSVP-TE) Parameters" registry located in 
        http://www.iana.org/assignments/rsvp-te- parameters".   

        This document introduces the following three new Attribute Bit 
        Flags: 

        Bit No      Name        Attribute   Attribute   RRO  Reference 

                                Flags Path  Flags Resv 

        ----------- ----------  ----------  ----------- ---  ------- 

        TBA by      Cost        Yes         Yes         Yes  This I-D 
        IANA        Collection 
                    Flag 
         

        TBA by      Delay       Yes         Yes         Yes  This I-D 
        IANA        Collection 
                    Flag 
         
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        TBA by      Delay       Yes         Yes         Yes  This I-D 
        IANA        Variation 
                    Collection             
                    Flag 
         

        5.2. ROUTE_RECORD subobject 

        IANA manages the "RSVP PARAMETERS" registry located at 
        http://www.iana.org/assignments/rsvp-parameters. This document 
        introduces the following three new RRO subobject: 

             Type         Name                        Reference 

             ---------    ----------------------      --------- 

             TBA by IANA  Cost subobject              This I-D 

             TBA by IANA  Delay subobject             This I-D 

             TBA by IANA  Delay Variation subobject   This I-D 

     8.2. Policy Control Failure Error subcodes  

        IANA manages the assignments in the "Error Codes and Globally-
        Defined Error Value Sub-Codes" section of the "RSVP PARAMETERS" 
        registry located at http://www.iana.org/assignments/rsvp-
        parameters. This document introduces the following three new 
        Policy Control Failure Error sub-code: 
          
        Value           Description                          Reference 
        -----           -----------                          --------- 
        TBA by IANA     Cost Recoding Rejected               This I-D 
        TBA by IANA     Delay Recoding Rejected              This I-D 
        TBA by IANA     Delay Variation Recoding Rejected    This I-D 
                                                  
      
     9. Acknowledgments 

        Authors would like to thank Ori Gerstel, Gabriele Maria 
        Galimberti, Luyuan Fang and Walid Wakim for their review 
        comments.  
      

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     10. References 

     10.1. 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. 

        [RFC5420] Farrel, A., Ed., Papadimitriou, D., Vasseur, JP., and 
                  A. Ayyangarps, "Encoding of Attributes for MPLS LSP 
                  Establishment Using Resource Reservation Protocol 
                  Traffic Engineering (RSVP-TE)", RFC 5420, February 
                  2009. 

        [RFC7471] S. Giacalone, D. Ward, J. Drake, A. Atlas, S. 
                  Previdi., "OSPF Traffic Engineering (TE) Metric 
                  Extensions", RFC 7471, March 2015.  

        [DRAFT-ISIS-TE-METRIC] S. Previdi, S. Giacalone, D. Ward, J. 
                  Drake, A. Atlas, C. Filsfils, "IS-IS Traffic 
                  Engineering (TE) Metric Extensions", draft-ietf-isis-
                  te-metric-extensions, work in progress. 

     10.2. 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. 

        [RFC2209] Braden, R. and L. Zhang, "Resource ReSerVation 
                  Protocol (RSVP) -- Version 1 Message Processing 
                  Rules", RFC 2209, September 1997. 

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

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

     Authors' Addresses 

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        Zafar Ali 
        Cisco Systems, Inc. 
        Email: zali@cisco.com 
      
        George Swallow 
        Cisco Systems, Inc. 
        swallow@cisco.com 
         
        Clarence Filsfils  
        Cisco Systems, Inc. 
        cfilsfil@cisco.com 
         
        Matt Hartley 
        Cisco Systems 
        Email: mhartley@cisco.com  
         
        Kenji Kumaki 
        KDDI Corporation 
        Email: ke-kumaki@kddi.com  
         
        Rudiger Kunze 
        Deutsche Telekom AG 
        Ruediger.Kunze@telekom.de  
         

         

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