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Versions: 00 01

LSR Working Group                                       U. Chunduri, Ed.
Internet-Draft                                                     R. Li
Intended status: Standards Track                              Huawei USA
Expires: January 17, 2019                                       K. Smith
                                                                Vodafone
                                                           July 16, 2018


              Resources for Preferred Path Routes in IGPs
                     draft-cls-ppr-te-attributes-00

Abstract

   Preferred Path Routing (PPR) is concerned with setting up the route
   for a given prefix as specified in the path description along with a
   corresponding data plane/forwarding identifier PPR-ID.  This document
   specifies an extension to PPR, a mechanism to perform resource
   reservations nodes on Preferred Path Routes (PPR) for IGPs (IS-IS,
   OSPFv2, OSPFv3).  This is done by specifying the resources that need
   to be reserved along the path using PPR path attributes.

Requirements Language

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in this
   document are to be interpreted as described in RFC2119 [RFC2119],
   RFC8174 [RFC8174] when, and only when they appear in all capitals, as
   shown here.

Status of This Memo

   This Internet-Draft is submitted in full conformance with the
   provisions of BCP 78 and BCP 79.

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF).  Note that other groups may also distribute
   working documents as Internet-Drafts.  The list of current Internet-
   Drafts is at https://datatracker.ietf.org/drafts/current/.

   Internet-Drafts are draft documents valid for a maximum of six months
   and may be updated, replaced, or obsoleted by other documents at any
   time.  It is inappropriate to use Internet-Drafts as reference
   material or to cite them other than as "work in progress."

   This Internet-Draft will expire on January 17, 2019.






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Copyright Notice

   Copyright (c) 2018 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
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of
   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   3
     1.1.  Acronyms  . . . . . . . . . . . . . . . . . . . . . . . .   3
   2.  Solution Overview . . . . . . . . . . . . . . . . . . . . . .   4
   3.  PPR Resource Reservation Related Parameters . . . . . . . . .   4
     3.1.  IS-IS Parameters  . . . . . . . . . . . . . . . . . . . .   4
       3.1.1.  Bandwidth Sub-TLV . . . . . . . . . . . . . . . . . .   4
       3.1.2.  Burst Size Sub-TLV  . . . . . . . . . . . . . . . . .   5
       3.1.3.  Per-hop Queuing Latency Sub-TLV . . . . . . . . . . .   5
       3.1.4.  Lifetime Sub-TLV  . . . . . . . . . . . . . . . . . .   6
       3.1.5.  Node Resource Capability Sub-TLV  . . . . . . . . . .   7
       3.1.6.  Node Status TLV . . . . . . . . . . . . . . . . . . .   8
       3.1.7.  IS-IS TE Metric Extensions  . . . . . . . . . . . . .   9
         3.1.7.1.  Per PPR queuing delay on the node . . . . . . . .  10
         3.1.7.2.  Unidirectional Utilized PPR Bandwidth . . . . . .  10
     3.2.  OSPFv2/OSPFv3 Parameters  . . . . . . . . . . . . . . . .  11
   4.  Elements of Procedure . . . . . . . . . . . . . . . . . . . .  11
   5.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  12
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  12
     6.1.  IGP Common Parameters . . . . . . . . . . . . . . . . . .  12
     6.2.  IS-IS Registries  . . . . . . . . . . . . . . . . . . . .  12
     6.3.  OSPFv2 Registries . . . . . . . . . . . . . . . . . . . .  13
     6.4.  OSPFv3 Registries . . . . . . . . . . . . . . . . . . . .  13
   7.  Security Considerations . . . . . . . . . . . . . . . . . . .  13
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  14
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  14
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  16







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1.  Introduction

   RSVP [RFC2205] allows out of band signaling along a specified path
   for resource reservations.  This is done by sending PATH/RESV message
   with flow-spec/filter-spec.  RSVP-TE [RFC3209], builds on RSVP
   protocol and defines new objects, modifies existing objects for MPLS
   LSP establishment with resources (reserved bandwidth).  This is less
   widely deployed perhaps due to soft-state maintenance, scaling and
   management overhead considerations.  [RFC8370] addresses some of the
   concerns by specifying refresh independence and per-peer flow control
   which would reduce processing cycles required to maintain LSP state.

   Segment Routing [I-D.ietf-spring-segment-routing] enables packet
   steering with a specified path in the packet itself.  This is defined
   for MPLS (with a set of stacked labels) and IPv6 (path described as
   list of IPv6 addresses in SRHeader) data planes called SR-MPLS and
   SRv6 respectively.  Routing with Preferred Paths with an optimized
   data plane (regardless of the type of data plane) is described in
   [I-D.chunduri-lsr-isis-preferred-path-routing].With PPR nodes in IGP
   compute the nexthops based on the path description for the prefix.
   This results in multiple benefits, including increased performance,
   compatibility and reduction of the data plane overhead of both path
   and services along the path.  While these allow packet steering on a
   specified path (either encoded in the packet itself or through a data
   plane identifier), they do not have any notion of QoS or resources
   reserved along the path.

   This document extends PPR to indicate the resources to be reserved
   along the preferred path.  These resources are required in some
   deployments [I-D.clt-dmm-tn-aware-mobility], for not only providing
   committed bandwidth or deterministic latency, but also for assuring
   overall service level guarantee in the network.  This approach does
   not require per-hop provisioning and also reduces the OPEX by
   minimizing the number of protocols needed and allows dynamism with
   FRR capabilities.  Unlike RSVP-TE [RFC3209], the approach does not
   rely on periodic refreshes for state synchronization between
   neighbors.

1.1.  Acronyms

   MPLS     -  Multi Protocol Label Switching

   MTU      -  Maximum Transferrable Unit

   PPR      -  Preferred Path Routing/Route

   PPR-ID   -  Preferred Path Route Identifier, a data plane identifier




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   SID      -  Segment Identifier

   SR-MPLS  -  Segment Routing with MPLS data plane

   SRH      -  Segment Routing Header - IPv6 routing Extension header

   SRv6     -  Segment Routing with Ipv6 data plane with SRH

   TE       -  Traffic Engineering

2.  Solution Overview

   Key aspect of the solution concerns with specifying the resources to
   be reserved along the preferred path
   [I-D.chunduri-lsr-isis-preferred-path-routing],
   [I-D.chunduri-lsr-ospf-preferred-path-routing].Reservations are
   expressed in terms of required resources (bandwidth), traffic
   characteristics (burst size), and service level parameters (expected
   maximum latency at each hop) based on the capabilities of each node
   and link along the path.  The second part of the solution is
   providing mechanism to indicate the status of the reservations
   requested i.e., if these have been honored by individual node/links
   in the path.  This is done by defining a new TLV/Sub-TLV in
   respective IGPS.  Another aspect is additional node level TLVs and
   extensions to [RFC7810] and [RFC7471] to provide accounting/usage
   statistics that have to be maintained at each node per preferred
   path.  All the above is specified for IS-IS/OSPFv2/OSPFv3 protocols.

3.  PPR Resource Reservation Related Parameters

   This section describes the encoding of additional TLVs and Sub-TLVs
   needed for resource reservations, associated accounting statistics
   for Preferred Path Routes in IS-IS/OSPFv2/OSPFv3 protocols.

3.1.  IS-IS Parameters

   [I-D.chunduri-lsr-isis-preferred-path-routing] defines few PPR-
   Attribute Sub-TLVs and this document extends the same for resources
   to be reserved through various Sub-TLVs.  The following additional
   IS-IS PPR-Attribute Sub-TLVs (Type - IANA TBD) are defined:

3.1.1.  Bandwidth Sub-TLV

   This is the required bandwidth for the PPR at each node/link in the
   path description.  It has minimum (CIR) and maximum bandwidth (PIR).






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       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                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Minimum bandwidth                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Maximum bandwidth                      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                    Figure 1: Bandwidth Sub-TLV Format

   o  Type: TBD (IANA)

   o  Length: 10 Octets

   o  Minimum bandwidth: The minimum bandwidth required, or CIR, unit
      Mbps

   o  Maximum bandwidth: The maximum bandwidth required, or PIR, unit
      Mbps

3.1.2.  Burst Size Sub-TLV

   This is the required burst for the PPR and is the maximum burst size.

       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                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Burst Size                             |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                    Figure 2: Burst Size Sub-TLV Format

   o  Type: TBD (IANA)

   o  Length: 6 Octets

   o  Burst size: The burst size, unit K bytes

3.1.3.  Per-hop Queuing Latency Sub-TLV

   This is the bounded latency for each hop on the PPR.  This is not the
   end to end latency.




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       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     |T|     Flags   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Latency                                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

             Figure 3: Per-hop Queuing Latency Sub-TLV Format

   o  Type: TBD (IANA)

   o  Length: 6 Octets

   o  Flags: 1 Octet

   T Bit - Set to 0, if Queuing Latency in milliseconds and Set to 1, If
   Queuing Latency in microseconds

   Latency: Expected maximum queuing latency for each hop

   When an expected hop-by-hop latency is given, the bandwidth
   expectation (CIR) MUST be present.

3.1.4.  Lifetime Sub-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           | Length        |       Reserved|     Flags     |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                        Lifetime                               |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+

                     Figure 4: Lifetime Sub-TLV Format

   o  Type: TBD (IANA)

   o  Length: 6 Octets

   o  Flags: 1 Octet

   o  Life Time: Life time of reservations done at each node in Seconds

   See the usage of this TLV and procedures after Lifetime expiration
   and related details in Section 4.




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3.1.5.  Node Resource Capability Sub-TLV

   The node Resource Capability Sub-TLV is defined within the body of
   the IS-IS Router Capability TLV [RFC7981].  This would allow what all
   TE parameters than can be supported by a node.  This sub-TLV lists
   all supported TE capabilities.

       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        |   RC Flags                    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


           Figure 5: IS-IS Reservation Capability Sub-TLV Format

   o  Type: TBD (IANA) from IS-IS Router Capability TLV Registry

   o  Length: Total length of the value field in bytes

   o  RC Flags: 2 Octets

        Reservation Capability Sub-TLV bit-field Format

           Reservation Capability bit-field Format

               0 1 2 3 4 5 6 7
              +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
              |B|S|L|T| Reserved            |E|
              +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



   o  Bit-0: B Bit: If this bit is set, Min/Max bandwidth reservation is
      supported by the node

   o  Bit-1: S Bit: If this bit is set burst size handling is supported
      by the node

   o  Bit-2: L Bit: If this bit is set per hop maximum queuing latency
      is supported by the node

   o  Bit-3: T Bit: If this bit is set an expiration timer for PPR-ID is
      supported by the node

   o  Bit-15: E Bit: If this bit is set one more 16-bit status bit-field
      is followed to this bit-field.




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   Rest of the bits undefined and transmitted as unset/0.

3.1.6.  Node Status TLV

   A new top level IS-IS TLV is defined to indicate the status of per
   preferred path TE resource reservation by each node, where it is part
   of one ore more PPRs.  This TLV should be generated by a node which
   is along the preferred path and which does the reservation of
   resources as indicated in the above TE parameters.

   Structure of this 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           | Length        |       Reserved                |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      //                 Sub-TLVs                                    //
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                     Figure 6: Node Status TLV Format

   o  Type: TBD (IANA) - From IS-IS top level TLV registry

   o  Length: Total length of the value field in bytes

   o  Sub-TLVs : One or more Sub-TLVs

   This document defines one of the Sub-TLVs in the above 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           | Length        |  PPR-ID Type   | PPR-ID Len   |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      //                PPR-ID Value (Size variable)                 //
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |16-bit status bit-field        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                Figure 7: Reservation Status Sub-TLV Format








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        Reservation Status Sub-TLV bit-field Format

           Reservation Status bit-field Format

               0 1 2 3 4 5 6 7
              +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
              |B|S|L|T| Reserved            |E|
              +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



   o  Bit-0: B Bit: If this bit is set, Min/Max bandwidth reservation
      for the PPR-ID is present

   o  Bit-1: S Bit: If this bit is set burst size handling for the PPR-
      ID is present

   o  Bit-2: L Bit: If this bit is set per hop maximum queuing latency
      enforcement is present

   o  Bit-3: T Bit: If this bit is set an expiration timer is present

   o  Bit-15: E Bit: If this bit is set one more 16-bit status bit-field
      is followed to this bit-field.

   Rest of the bits undefined and transmitted as unset/0.

   Once preferred path is received through IGP as defined in
   [I-D.chunduri-lsr-isis-preferred-path-routing] and with the
   extensions as specified in this document for resources reservation, a
   node on the path allocate the resources requested in the hardware.
   However after resources are allocated in the hardware, status of the
   same is given to the respective IGP in the control plane, which would
   enable IGP to indicate the status in the structure described above.
   If record is missing in the above structure, for that preferred path
   reservations could have been withdrawn.

3.1.7.  IS-IS TE Metric Extensions

   Once resource reservations are done, usage statistics need to be
   maintained and further transported to a central entity.  Each node on
   PPR path, the following stat(s) need to be maintained.  More
   parameters TBD.








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3.1.7.1.  Per PPR queuing delay on the node

   This Sub-TLV advertises the average PPR queue delay variation in the
   node.  This is a 24-bit field carries the average PPR queue delay
   over a configurable interval in microseconds The delay variation
   advertised.  The format of this Sub-TLV is shown in the following
   diagram:

      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     |               Avg. queue Delay Variation      |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |PPR-ID Type    | PPR-ID Len    | PPR-ID Value (Size variable) //
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+



                   Figure 8: QUEUE Delay Sub-TLV Format

   o  where:

   Type: TBD IANA - from the node capabilities TLV.

   Length: Variable

   RESERVED: This field is reserved for future use.  It MUST be set to 0
   when sent and MUST be ignored when received.

   Delay Variation: This 24-bit field carries the average PPR queue
   delay variation over a configurable interval in microseconds, encoded
   as an integer value.  When set to 0, it has not been measured.  When
   set to the maximum value 16,777,215 (16.777215 sec), then the delay
   is at least that value and may be larger.

3.1.7.2.  Unidirectional Utilized PPR Bandwidth

   This Sub-TLV advertises the PPR bandwidth utilization per PPR-ID in
   the node.  The bandwidth utilization advertised by this Sub-TLV MUST
   be the bandwidth from the system originating this Sub-TLV.  The
   format of this Sub-TLV is shown in the following diagram:








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      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    |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |                     Utilized Bandwidth                        |
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
      |PPR-ID Type    | PPR-ID Len    | PPR-ID Value (Size variable) //
      +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+


                           Figure 9: TLV Format

   where:

   o  Type: IANA (TBD) - from the "Sub-TLVs for TLVs 22, 23, 141, 222,
      and 223" registry:

   o  Length: Total length of the value field in bytes

   o  Utilized Bandwidth: This field carries the bandwidth utilization
      per PPR-ID on a link , forwarding adjacency, or bundled link in
      IEEE floating-point format with units of bytes per second.
      Considerations for a link or forwarding adjacency or for a bundled
      link is similar to Section 4.7 of RFC 7810.

3.2.  OSPFv2/OSPFv3 Parameters

   Similar extensions are needed for OSPFv2 and OSPFv3 PPR TLV's PPR
   attributes except the Type (respective suggested values in
   Section 6.3 and Section 6.4) and Length fields are 2 octets each.
   New Sub-TLVs are also needed for Node status similar to Figure 6 and
   TE parameter extensions similar to Section 3.1.7 for OSPFv2 and
   OSPFv3 protocols.

4.  Elements of Procedure

   If a PPR has attributes as specified in Section 3 for reserving
   resources along the path, individual nodes in the path description
   acts on the path attributes.  Section 3 defines few PPR-Attributes
   for allocating/reserving resources in each node of the PPR path
   description.  Presence of these Sub-TLVs instruct to provision the
   hardware with appropriate parameters as specified.  Traffic
   accounting should happen concerning to the resource in question, when
   the actual data traffic hits for the PPR-ID in the forwarding plane.
   New attribute values can be updated for an existing PPR-ID and when
   the PPR-ID is withdrawn corresponding resources along the path MUST
   be removed along with the Status TLV Figure 7 update.



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   After the data plane is programmed for a TE, a TE state is created.
   The TE state life is determined by the "Life Time" in the PPR
   attribute Sub-TLV.  Whenever there is a packet processed by a TE
   state for the respective PPR-ID, the associated timer for the TE
   state is reset.  If the timer of a TE state is expired, the TE state
   will be erased and the associated resource can be released and
   accordingly and Node Status TLV Figure 7 would be updated.  In order
   to keep the TE state active, IGP LSP/LSA refresh has to happen and it
   should be less than the time of "Life time" attribute
   (Section 3.1.4).

5.  Acknowledgements

   TBD.

6.  IANA Considerations

6.1.  IGP Common Parameters

   This document requests additional IANA registries in an IANA managed
   registry "Interior Gateway Protocol (IGP) Parameters" for various PPR
   TLV parameters.  The registration procedure is based on the "Expert
   Review" as defined in [RFC8126].  The suggested registry names are:

6.2.  IS-IS Registries

   This document requests IANA to create a new Sub-TLV registry for IS-
   IS PPR TLV Section 3 with the following initial entries (suggested
   values):

   Sub-TLV #   Sub-TLV Name
   ---------   ---------------------------------------------------------

    5          Bandwidth (Section 3.1.1)

    6          Burst Size (Section 3.1.2)

    7          Per-hop Queuing Latency (Section 3.1.3)

    8          Lifetime (Section 3.1.4)

   This document also requests a new Sub-TLV code point from IS-IS
   Router Capability TLV Registry as defined by [RFC8126] and an IS-IS
   top level Status TLV code point from IANA IS-IS TLV code- point
   registry.






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6.3.  OSPFv2 Registries

   This document requests IANA to create a new Sub-TLV registry for
   OSPFv2 PPR TLV Section 3 with the following initial entries
   (suggested values):

   Sub-TLV #   Sub-TLV Name
   ---------   ---------------------------------------------------------

    4          Bandwidth (Section 3.2)

    5          Burst Size (Section 3.2)

    6          Per-hop Queuing Latency (Section 3.2)

    7          Lifetime (Section 3.2)

6.4.  OSPFv3 Registries

   This document requests IANA to create a new Sub-TLV registry for
   OSPV3 PPR TLV Section 3 with the following initial entries (suggested
   values):

   Sub-TLV #   Sub-TLV Name
   ---------   ---------------------------------------------------------

    4          Bandwidth (Section 3.2)

    5          Burst Size (Section 3.2)

    6          Per-hop Queuing Latency (Section 3.2)

    7          Lifetime (Section 3.2)

7.  Security Considerations

   Security concerns for IS-IS are addressed in [RFC5304] and [RFC5310].
   Further security analysis for IS-IS protocol is done in [RFC7645]
   with detailed analysis of various security threats and why [RFC5304]
   should not be used in the deployments.

   OSPF security extensions are described in [RFC2328] and [RFC7684] and
   these apply to the extensions specified in this document.  While OSPF
   is under a single administrative domain, there can be deployments
   where potential attackers have access to one or more networks in the
   OSPF routing domain.  In these deployments, stronger authentication
   mechanisms such as those specified in [RFC7474] SHOULD be used.




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   Advertisement of the additional information defined in this document
   introduces no new security concerns in IS-IS or OSPF protocols.

8.  References

8.1.  Normative References

   [I-D.chunduri-lsr-isis-preferred-path-routing]
              Chunduri, U., Li, R., White, R., Tantsura, J., Contreras,
              L., and Y. Qu, "Preferred Path Routing (PPR) in IS-IS",
              draft-chunduri-lsr-isis-preferred-path-routing-01 (work in
              progress), July 2018.

   [I-D.chunduri-lsr-ospf-preferred-path-routing]
              Chunduri, U., Qu, Y., White, R., Tantsura, J., and L.
              Contreras, "Preferred Path Routing (PPR) in OSPF", draft-
              chunduri-lsr-ospf-preferred-path-routing-01 (work in
              progress), July 2018.

   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", BCP 14, RFC 2119,
              DOI 10.17487/RFC2119, March 1997,
              <https://www.rfc-editor.org/info/rfc2119>.

8.2.  Informative References

   [I-D.clt-dmm-tn-aware-mobility]
              Chunduri, U., Li, R., Tantsura, J., Contreras, L., and X.
              Foy, "Transport Network aware Mobility for 5G", draft-clt-
              dmm-tn-aware-mobility-01 (work in progress), July 2018.

   [I-D.ietf-spring-segment-routing]
              Filsfils, C., Previdi, S., Ginsberg, L., Decraene, B.,
              Litkowski, S., and R. Shakir, "Segment Routing
              Architecture", draft-ietf-spring-segment-routing-15 (work
              in progress), January 2018.

   [RFC2205]  Braden, R., Ed., Zhang, L., Berson, S., Herzog, S., and S.
              Jamin, "Resource ReSerVation Protocol (RSVP) -- Version 1
              Functional Specification", RFC 2205, DOI 10.17487/RFC2205,
              September 1997, <https://www.rfc-editor.org/info/rfc2205>.

   [RFC2328]  Moy, J., "OSPF Version 2", STD 54, RFC 2328,
              DOI 10.17487/RFC2328, April 1998,
              <https://www.rfc-editor.org/info/rfc2328>.






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   [RFC3209]  Awduche, D., Berger, L., Gan, D., Li, T., Srinivasan, V.,
              and G. Swallow, "RSVP-TE: Extensions to RSVP for LSP
              Tunnels", RFC 3209, DOI 10.17487/RFC3209, December 2001,
              <https://www.rfc-editor.org/info/rfc3209>.

   [RFC5304]  Li, T. and R. Atkinson, "IS-IS Cryptographic
              Authentication", RFC 5304, DOI 10.17487/RFC5304, October
              2008, <https://www.rfc-editor.org/info/rfc5304>.

   [RFC5310]  Bhatia, M., Manral, V., Li, T., Atkinson, R., White, R.,
              and M. Fanto, "IS-IS Generic Cryptographic
              Authentication", RFC 5310, DOI 10.17487/RFC5310, February
              2009, <https://www.rfc-editor.org/info/rfc5310>.

   [RFC7471]  Giacalone, S., Ward, D., Drake, J., Atlas, A., and S.
              Previdi, "OSPF Traffic Engineering (TE) Metric
              Extensions", RFC 7471, DOI 10.17487/RFC7471, March 2015,
              <https://www.rfc-editor.org/info/rfc7471>.

   [RFC7474]  Bhatia, M., Hartman, S., Zhang, D., and A. Lindem, Ed.,
              "Security Extension for OSPFv2 When Using Manual Key
              Management", RFC 7474, DOI 10.17487/RFC7474, April 2015,
              <https://www.rfc-editor.org/info/rfc7474>.

   [RFC7645]  Chunduri, U., Tian, A., and W. Lu, "The Keying and
              Authentication for Routing Protocol (KARP) IS-IS Security
              Analysis", RFC 7645, DOI 10.17487/RFC7645, September 2015,
              <https://www.rfc-editor.org/info/rfc7645>.

   [RFC7684]  Psenak, P., Gredler, H., Shakir, R., Henderickx, W.,
              Tantsura, J., and A. Lindem, "OSPFv2 Prefix/Link Attribute
              Advertisement", RFC 7684, DOI 10.17487/RFC7684, November
              2015, <https://www.rfc-editor.org/info/rfc7684>.

   [RFC7810]  Previdi, S., Ed., Giacalone, S., Ward, D., Drake, J., and
              Q. Wu, "IS-IS Traffic Engineering (TE) Metric Extensions",
              RFC 7810, DOI 10.17487/RFC7810, May 2016,
              <https://www.rfc-editor.org/info/rfc7810>.

   [RFC7981]  Ginsberg, L., Previdi, S., and M. Chen, "IS-IS Extensions
              for Advertising Router Information", RFC 7981,
              DOI 10.17487/RFC7981, October 2016,
              <https://www.rfc-editor.org/info/rfc7981>.

   [RFC8126]  Cotton, M., Leiba, B., and T. Narten, "Guidelines for
              Writing an IANA Considerations Section in RFCs", BCP 26,
              RFC 8126, DOI 10.17487/RFC8126, June 2017,
              <https://www.rfc-editor.org/info/rfc8126>.



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   [RFC8174]  Leiba, B., "Ambiguity of Uppercase vs Lowercase in RFC
              2119 Key Words", BCP 14, RFC 8174, DOI 10.17487/RFC8174,
              May 2017, <https://www.rfc-editor.org/info/rfc8174>.

   [RFC8370]  Beeram, V., Ed., Minei, I., Shakir, R., Pacella, D., and
              T. Saad, "Techniques to Improve the Scalability of RSVP-TE
              Deployments", RFC 8370, DOI 10.17487/RFC8370, May 2018,
              <https://www.rfc-editor.org/info/rfc8370>.

Authors' Addresses

   Uma Chunduri (editor)
   Huawei USA
   2330 Central Expressway
   Santa Clara, CA  95050
   USA

   Email: uma.chunduri@huawei.com


   Richard Li
   Huawei USA
   2330 Central Expressway
   Santa Clara, CA  95050
   USA

   Email: renwei.li@huawei.com


   Kevin Smith
   Vodafone
   UK

   Email: kevin.smith@vodafone.com

















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