A YANG Data Model for Path Computation Element Communications Protocol (PCEP)
draft-pkd-pce-pcep-yang-06

PCE Working Group                                            R. Pobbathi
Internet-Draft                                                 V. KumarS
Intended status: Standards Track                           D. Dhody, Ed.
Expires: August 27, 2015                             Huawei Technologies
                                                             J. Hardwick
                                                              Metaswitch
                                                       February 23, 2015


 A YANG Data Model for Path Computation Element Communications Protocol
                                 (PCEP)
                       draft-pkd-pce-pcep-yang-02

Abstract

   This document defines a YANG data model for the management of Path
   Computation Element communications Protocol (PCEP) for communications
   between a Path Computation Client (PCC) and a Path Computation
   Element (PCE), or between two PCEs.  The data model includes
   configuration data and state data (status information and counters
   for the collection of statistics).

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 http://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 August 27, 2015.

Copyright Notice

   Copyright (c) 2015 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
   (http://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents



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   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  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Requirements Language . . . . . . . . . . . . . . . . . . . .   3
   3.  Terminology and Notation  . . . . . . . . . . . . . . . . . .   3
     3.1.  Tree Diagrams . . . . . . . . . . . . . . . . . . . . . .   4
     3.2.  Prefixes in Data Node Names . . . . . . . . . . . . . . .   4
   4.  Objectives  . . . . . . . . . . . . . . . . . . . . . . . . .   4
   5.  The Design of PCEP Data Model . . . . . . . . . . . . . . . .   5
     5.1.  The Entity Lists  . . . . . . . . . . . . . . . . . . . .  12
     5.2.  The Peer Lists  . . . . . . . . . . . . . . . . . . . . .  12
     5.3.  The Session Lists . . . . . . . . . . . . . . . . . . . .  13
     5.4.  Notifications . . . . . . . . . . . . . . . . . . . . . .  13
   6.  Advanced PCE Features . . . . . . . . . . . . . . . . . . . .  13
   7.  PCEP YANG Module  . . . . . . . . . . . . . . . . . . . . . .  14
   8.  Security Considerations . . . . . . . . . . . . . . . . . . .  58
   9.  Manageability Considerations  . . . . . . . . . . . . . . . .  58
     9.1.  Control of Function and Policy  . . . . . . . . . . . . .  58
     9.2.  Information and Data Models . . . . . . . . . . . . . . .  58
     9.3.  Liveness Detection and Monitoring . . . . . . . . . . . .  58
     9.4.  Verify Correct Operations . . . . . . . . . . . . . . . .  58
     9.5.  Requirements On Other Protocols . . . . . . . . . . . . .  59
     9.6.  Impact On Network Operations  . . . . . . . . . . . . . .  59
   10. IANA Considerations . . . . . . . . . . . . . . . . . . . . .  59
   11. Acknowledgements  . . . . . . . . . . . . . . . . . . . . . .  59
   12. References  . . . . . . . . . . . . . . . . . . . . . . . . .  59
     12.1.  Normative References . . . . . . . . . . . . . . . . . .  59
     12.2.  Informative References . . . . . . . . . . . . . . . . .  60
   Appendix A.  Contributor Addresses  . . . . . . . . . . . . . . .  61

1.  Introduction

   The Path Computation Element (PCE) defined in [RFC4655] is an entity
   that is capable of computing a network path or route based on a
   network graph, and applying computational constraints.  A Path
   Computation Client (PCC) may make requests to a PCE for paths to be
   computed.

   PCEP is the communication protocol between a PCC and PCE and is
   defined in [RFC5440].  PCEP interactions include path computation
   requests and path computation replies as well as notifications of
   specific states related to the use of a PCE in the context of



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   Multiprotocol Label Switching (MPLS) and Generalized MPLS (GMPLS)
   Traffic Engineering (TE).

   This document defines a YANG [RFC6020] data model for the management
   of PCEP speakers.  It is important to establish a common data model
   for how PCEP speakers are identified, configured, and monitored.  The
   data model includes configuration data and state data (status
   information and counters for the collection of statistics).

   This document contains a specification of the base PCEP YANG module,
   "ietf-pcep" which provides the basic PCEP [RFC5440] data model.

   [Editor's Note: Further modules augmenting the data model with
   advanced features maybe handled in a future revision or a separate
   document.]

2.  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].

3.  Terminology and Notation

   This document uses the terminology defined in [RFC4655] and
   [RFC5440].  In particular, it uses the following acronyms.

   o  Path Computation Request message (PCReq).

   o  Path Computation Reply message (PCRep).

   o  Notification message (PCNtf).

   o  Error message (PCErr).

   o  Request Parameters object (RP).

   o  Synchronization Vector object (SVEC).

   o  Explicit Route object (ERO).

   This document also uses the following terms defined in [RFC7420]:

   o  PCEP entity: a local PCEP speaker.

   o  PCEP peer: to refer to a remote PCEP speaker.





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   o  PCEP speaker: where it is not necessary to distinguish between
      local and remote.

3.1.  Tree Diagrams

   A graphical representation of the complete data tree is presented in
   Section 5.  The meaning of the symbols in these diagrams is as
   follows and as per [I-D.ietf-netmod-rfc6087bis]:

   o  Brackets "[" and "]" enclose list keys.

   o  Curly braces "{" and "}" contain names of optional features that
      make the corresponding node conditional.

   o  Abbreviations before data node names: "rw" means configuration
      (read-write), and "ro" state data (read-only).

   o  Symbols after data node names: "?" means an optional node and "*"
      denotes a "list" or "leaf-list".

   o  Parentheses enclose choice and case nodes, and case nodes are also
      marked with a colon (":").

   o  Ellipsis ("...") stands for contents of subtrees that are not
      shown.

3.2.  Prefixes in Data Node Names

   In this document, names of data nodes and other data model objects
   are often used without a prefix, as long as it is clear from the
   context in which YANG module each name is defined.  Otherwise, names
   are prefixed using the standard prefix associated with the
   corresponding YANG module, as shown in Table 1.

                 +--------+-----------------+-----------+
                 | Prefix | YANG module     | Reference |
                 +--------+-----------------+-----------+
                 | yang   | ietf-yang-types | [RFC6991] |
                 | inet   | ietf-inet-types | [RFC6991] |
                 +--------+-----------------+-----------+

             Table 1: Prefixes and corresponding YANG modules

4.  Objectives

   This section describes some of the design objectives for the model:





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   o  In case of existing implementations, it needs to map the data
      model defined in this document to their proprietary native data
      model.  To facilitate such mappings, the data model should be
      simple.

   o  The data model should be suitable for new implementations to use
      as is.

   o  Mapping to the PCEP MIB Module should be clear.

   o  The data model should allow for static configurations of peers.

   o  The data model should include read-only counters in order to
      gather statistics for sent and received PCEP messages, received
      messages with errors, and messages that could not be sent due to
      errors.

   o  It should be fairly straightforward to augment the base data model
      for advanced PCE features.

5.  The Design of PCEP Data Model

   The module, "ietf-pcep", defines the basic components of a PCE
   speaker.

  module: ietf-pcep
     +--rw pcep
     |  +--rw entity* [addr]
     |     +--rw addr                          inet:ip-address
     |     +--rw enabled?                      boolean
     |     +--rw role                          pcep-role
     |     +--rw description?                  string
     |     +--rw pce-info
     |     |  +--rw scope
     |     |  |  +--rw intra-area-scope?           boolean
     |     |  |  +--rw intra-area-pref?            uint8
     |     |  |  +--rw inter-area-scope?           boolean
     |     |  |  +--rw inter-area-scope-default?   boolean
     |     |  |  +--rw inter-area-pref?            uint8
     |     |  |  +--rw inter-as-scope?             boolean
     |     |  |  +--rw inter-as-scope-default?     boolean
     |     |  |  +--rw inter-as-pref?              uint8
     |     |  |  +--rw inter-layer-scope?          boolean
     |     |  |  +--rw inter-layer-pref?           uint8
     |     |  +--rw domain
     |     |  |  +--rw domain-type?   pce-domain-type
     |     |  |  +--rw domain?        pce-domain
     |     |  +--rw neigh-domains



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     |     |  |  +--rw domain* [domain-type domain]
     |     |  |     +--rw domain-type    pce-domain-type
     |     |  |     +--rw domain         pce-domain
     |     |  +--rw capability
     |     |     +--rw gmpls?                 boolean
     |     |     +--rw bi-dir?                boolean
     |     |     +--rw diverse?               boolean
     |     |     +--rw load-balance?          boolean
     |     |     +--rw synchronize?           boolean
     |     |     +--rw objective-function?    boolean
     |     |     +--rw add-path-constraint?   boolean
     |     |     +--rw prioritization?        boolean
     |     |     +--rw multi-request?         boolean
     |     |     +--rw gco?                   boolean
     |     |     +--rw p2mp?                  boolean
     |     +--rw connect-timer?                uint32
     |     +--rw connect-max-retry?            uint32
     |     +--rw init-backoff-timer?           uint32
     |     +--rw max-backoff-timer?            uint32
     |     +--rw open-wait-timer?              uint32
     |     +--rw keep-wait-timer?              uint32
     |     +--rw keep-alive-timer?             uint32
     |     +--rw dead-timer?                   uint32
     |     +--rw allow-negotiation?            boolean
     |     +--rw max-keep-alive-timer?         uint32
     |     +--rw max-dead-timer?               uint32
     |     +--rw min-keep-alive-timer?         uint32
     |     +--rw min-dead-timer?               uint32
     |     +--rw sync-timer?                   uint32
     |     +--rw request-timer?                uint32
     |     +--rw max-sessions?                 uint32
     |     +--rw max-unknown-reqs?             uint32
     |     +--rw max-unknown-msgs?             uint32
     |     +--rw pcep-notification-max-rate    uint32
     |     +--rw peers
     |        +--rw peer* [addr]
     |           +--rw addr           inet:ip-address
     |           +--rw description?   string
     |           +--rw pce-info
     |              +--rw scope
     |              |  +--rw intra-area-scope?           boolean
     |              |  +--rw intra-area-pref?            uint8
     |              |  +--rw inter-area-scope?           boolean
     |              |  +--rw inter-area-scope-default?   boolean
     |              |  +--rw inter-area-pref?            uint8
     |              |  +--rw inter-as-scope?             boolean
     |              |  +--rw inter-as-scope-default?     boolean
     |              |  +--rw inter-as-pref?              uint8



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     |              |  +--rw inter-layer-scope?          boolean
     |              |  +--rw inter-layer-pref?           uint8
     |              +--rw domain
     |              |  +--rw domain-type?   pce-domain-type
     |              |  +--rw domain?        pce-domain
     |              +--rw neigh-domains
     |              |  +--rw domain* [domain-type domain]
     |              |     +--rw domain-type    pce-domain-type
     |              |     +--rw domain         pce-domain
     |              +--rw capability
     |                 +--rw gmpls?                 boolean
     |                 +--rw bi-dir?                boolean
     |                 +--rw diverse?               boolean
     |                 +--rw load-balance?          boolean
     |                 +--rw synchronize?           boolean
     |                 +--rw objective-function?    boolean
     |                 +--rw add-path-constraint?   boolean
     |                 +--rw prioritization?        boolean
     |                 +--rw multi-request?         boolean
     |                 +--rw gco?                   boolean
     |                 +--rw p2mp?                  boolean
     +--ro pcep-state
        +--ro entity* [addr]
           +--ro index?                  uint32
           +--ro addr                    inet:ip-address
           +--ro admin-status?           pcep-admin-status
           +--ro oper-status?            pcep-admin-status
           +--ro role?                   pcep-role
           +--ro pce-info
           |  +--ro scope
           |  |  +--ro intra-area-scope?           boolean
           |  |  +--ro intra-area-pref?            uint8
           |  |  +--ro inter-area-scope?           boolean
           |  |  +--ro inter-area-scope-default?   boolean
           |  |  +--ro inter-area-pref?            uint8
           |  |  +--ro inter-as-scope?             boolean
           |  |  +--ro inter-as-scope-default?     boolean
           |  |  +--ro inter-as-pref?              uint8
           |  |  +--ro inter-layer-scope?          boolean
           |  |  +--ro inter-layer-pref?           uint8
           |  +--ro domain
           |  |  +--ro domain-type?   pce-domain-type
           |  |  +--ro domain?        pce-domain
           |  +--ro neigh-domains
           |  |  +--ro domain* [domain-type domain]
           |  |     +--ro domain-type    pce-domain-type
           |  |     +--ro domain         pce-domain
           |  +--ro capability



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           |     +--ro gmpls?                 boolean
           |     +--ro bi-dir?                boolean
           |     +--ro diverse?               boolean
           |     +--ro load-balance?          boolean
           |     +--ro synchronize?           boolean
           |     +--ro objective-function?    boolean
           |     +--ro add-path-constraint?   boolean
           |     +--ro prioritization?        boolean
           |     +--ro multi-request?         boolean
           |     +--ro gco?                   boolean
           |     +--ro p2mp?                  boolean
           +--ro connect-timer?          uint32
           +--ro connect-max-retry?      uint32
           +--ro init-backoff-timer?     uint32
           +--ro max-backoff-timer?      uint32
           +--ro open-wait-timer?        uint32
           +--ro keep-wait-timer?        uint32
           +--ro keep-alive-timer?       uint32
           +--ro dead-timer?             uint32
           +--ro allow-negotiation?      boolean
           +--ro max-keep-alive-timer?   uint32
           +--ro max-dead-timer?         uint32
           +--ro min-keep-alive-timer?   uint32
           +--ro min-dead-timer?         uint32
           +--ro sync-timer?             uint32
           +--ro request-timer?          uint32
           +--ro max-sessions?           uint32
           +--ro max-unknown-reqs?       uint32
           +--ro max-unknown-msgs?       uint32
           +--ro peers
              +--ro peer* [addr]
                 +--ro addr                        inet:ip-address
                 +--ro role?                       pcep-role
                 +--ro pce-info
                 |  +--ro scope
                 |  |  +--ro intra-area-scope?           boolean
                 |  |  +--ro intra-area-pref?            uint8
                 |  |  +--ro inter-area-scope?           boolean
                 |  |  +--ro inter-area-scope-default?   boolean
                 |  |  +--ro inter-area-pref?            uint8
                 |  |  +--ro inter-as-scope?             boolean
                 |  |  +--ro inter-as-scope-default?     boolean
                 |  |  +--ro inter-as-pref?              uint8
                 |  |  +--ro inter-layer-scope?          boolean
                 |  |  +--ro inter-layer-pref?           uint8
                 |  +--ro domain
                 |  |  +--ro domain-type?   pce-domain-type
                 |  |  +--ro domain?        pce-domain



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                 |  +--ro neigh-domains
                 |  |  +--ro domain* [domain-type domain]
                 |  |     +--ro domain-type    pce-domain-type
                 |  |     +--ro domain         pce-domain
                 |  +--ro capability
                 |     +--ro gmpls?                 boolean
                 |     +--ro bi-dir?                boolean
                 |     +--ro diverse?               boolean
                 |     +--ro load-balance?          boolean
                 |     +--ro synchronize?           boolean
                 |     +--ro objective-function?    boolean
                 |     +--ro add-path-constraint?   boolean
                 |     +--ro prioritization?        boolean
                 |     +--ro multi-request?         boolean
                 |     +--ro gco?                   boolean
                 |     +--ro p2mp?                  boolean
                 +--ro discontinuity-time?         yang:timestamp
                 +--ro initiate-session?           boolean
                 +--ro session-exists?             boolean
                 +--ro num-sess-setup-ok?          yang:counter32
                 +--ro num-sess-setup-fail?        yang:counter32
                 +--ro session-up-time?            yang:timestamp
                 +--ro session-fail-time?          yang:timestamp
                 +--ro session-fail-up-time?       yang:timestamp
                 +--ro avg-rsp-time?               uint32
                 +--ro lwm-rsp-time?               uint32
                 +--ro hwm-rsp-time?               uint32
                 +--ro num-pcreq-sent?             yang:counter32
                 +--ro num-pcreq-rcvd?             yang:counter32
                 +--ro num-pcrep-sent?             yang:counter32
                 +--ro num-pcrep-rcvd?             yang:counter32
                 +--ro num-pcerr-sent?             yang:counter32
                 +--ro num-pcerr-rcvd?             yang:counter32
                 +--ro num-pcntf-sent?             yang:counter32
                 +--ro num-pcntf-rcvd?             yang:counter32
                 +--ro num-keepalive-sent?         yang:counter32
                 +--ro num-keepalive-rcvd?         yang:counter32
                 +--ro num-unknown-rcvd?           yang:counter32
                 +--ro num-corrupt-rcvd?           yang:counter32
                 +--ro num-req-sent?               yang:counter32
                 +--ro num-svec-sent?              yang:counter32
                 +--ro num-svec-req-sent?          yang:counter32
                 +--ro num-req-sent-pend-rep?      yang:counter32
                 +--ro num-req-sent-ero-rcvd?      yang:counter32
                 +--ro num-req-sent-nopath-rcvd?   yang:counter32
                 +--ro num-req-sent-cancel-rcvd?   yang:counter32
                 +--ro num-req-sent-error-rcvd?    yang:counter32
                 +--ro num-req-sent-timeout?       yang:counter32



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                 +--ro num-req-sent-cancel-sent?   yang:counter32
                 +--ro num-req-rcvd?               yang:counter32
                 +--ro num-svec-rcvd?              yang:counter32
                 +--ro num-svec-req-rcvd?          yang:counter32
                 +--ro num-req-rcvd-pend-rep?      yang:counter32
                 +--ro num-req-rcvd-ero-sent?      yang:counter32
                 +--ro num-req-rcvd-nopath-sent?   yang:counter32
                 +--ro num-req-rcvd-cancel-sent?   yang:counter32
                 +--ro num-req-rcvd-error-sent?    yang:counter32
                 +--ro num-req-rcvd-cancel-rcvd?   yang:counter32
                 +--ro num-rep-rcvd-unknown?       yang:counter32
                 +--ro num-req-rcvd-unknown?       yang:counter32
                 +--ro num-req-sent-closed?        yang:counter32
                 +--ro num-req-rcvd-closed?        yang:counter32
                 +--ro sessions
                    +--ro session* [initiator]
                       +--ro initiator                   pcep-initiator
                       +--ro state-last-change?          yang:timestamp
                       +--ro state?                      pcep-sess-state
                       +--ro connect-retry?              yang:counter32
                       +--ro local-id?                   uint32
                       +--ro remote-id?                  uint32
                       +--ro keepalive-timer?            uint32
                       +--ro peer-keepalive-timer?       uint32
                       +--ro dead-timer?                 uint32
                       +--ro peer-dead-timer?            uint32
                       +--ro ka-hold-time-rem?           uint32
                       +--ro overloaded?                 boolean
                       +--ro overload-time?              uint32
                       +--ro peer-overloaded?            boolean
                       +--ro peer-overload-time?         uint32
                       +--ro discontinuity-time?         yang:timestamp
                       +--ro avg-rsp-time?               uint32
                       +--ro lwm-rsp-time?               uint32
                       +--ro hwm-rsp-time?               uint32
                       +--ro num-pcreq-sent?             yang:counter32
                       +--ro num-pcreq-rcvd?             yang:counter32
                       +--ro num-pcrep-sent?             yang:counter32
                       +--ro num-pcrep-rcvd?             yang:counter32
                       +--ro num-pcerr-sent?             yang:counter32
                       +--ro num-pcerr-rcvd?             yang:counter32
                       +--ro num-pcntf-sent?             yang:counter32
                       +--ro num-pcntf-rcvd?             yang:counter32
                       +--ro num-keepalive-sent?         yang:counter32
                       +--ro num-keepalive-rcvd?         yang:counter32
                       +--ro num-unknown-rcvd?           yang:counter32
                       +--ro num-corrupt-rcvd?           yang:counter32
                       +--ro num-req-sent?               yang:counter32



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                       +--ro num-svec-sent?              yang:counter32
                       +--ro num-svec-req-sent?          yang:counter32
                       +--ro num-req-sent-pend-rep?      yang:counter32
                       +--ro num-req-sent-ero-rcvd?      yang:counter32
                       +--ro num-req-sent-nopath-rcvd?   yang:counter32
                       +--ro num-req-sent-cancel-rcvd?   yang:counter32
                       +--ro num-req-sent-error-rcvd?    yang:counter32
                       +--ro num-req-sent-timeout?       yang:counter32
                       +--ro num-req-sent-cancel-sent?   yang:counter32
                       +--ro num-req-rcvd?               yang:counter32
                       +--ro num-svec-rcvd?              yang:counter32
                       +--ro num-svec-req-rcvd?          yang:counter32
                       +--ro num-req-rcvd-pend-rep?      yang:counter32
                       +--ro num-req-rcvd-ero-sent?      yang:counter32
                       +--ro num-req-rcvd-nopath-sent?   yang:counter32
                       +--ro num-req-rcvd-cancel-sent?   yang:counter32
                       +--ro num-req-rcvd-error-sent?    yang:counter32
                       +--ro num-req-rcvd-cancel-rcvd?   yang:counter32
                       +--ro num-rep-rcvd-unknown?       yang:counter32
                       +--ro num-req-rcvd-unknown?       yang:counter32
  notifications:
     +---n pcep-session-up
     |  +--ro entity-addr?         leafref
     |  +--ro peer-addr?           leafref
     |  +--ro session-initiator?   leafref
     |  +--ro state-last-change?   yang:timestamp
     |  +--ro state?               pcep-sess-state
     +---n pcep-session-down
     |  +--ro entity-addr?         leafref
     |  +--ro peer-addr?           leafref
     |  +--ro session-initiator?   pcep-initiator
     |  +--ro state-last-change?   yang:timestamp
     |  +--ro state?               pcep-sess-state
     +---n pcep-session-local-overload
     |  +--ro entity-addr?         leafref
     |  +--ro peer-addr?           leafref
     |  +--ro session-initiator?   leafref
     |  +--ro overloaded?          boolean
     |  +--ro overload-time?       uint32
     +---n pcep-session-local-overload-clear
     |  +--ro entity-addr?   leafref
     |  +--ro peer-addr?     leafref
     |  +--ro overloaded?    boolean
     +---n pcep-session-peer-overload
     |  +--ro entity-addr?          leafref
     |  +--ro peer-addr?            leafref
     |  +--ro session-initiator?    leafref
     |  +--ro peer-overloaded?      boolean



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     |  +--ro peer-overload-time?   uint32
     +---n pcep-session-peer-overload-clear
        +--ro entity-addr?       leafref
        +--ro peer-addr?         leafref
        +--ro peer-overloaded?   boolean


5.1.  The Entity Lists

   The PCEP yang module may contain status information for multiple
   logical local PCEP entities.  There are several scenarios in which
   there may be more than one local PCEP entity, it is listed in
   [RFC7420].

   The data model for PCEP presented in this document uses a flat list
   of entities.  Each entity in the list is identified by its IP address
   (addr-type, addr).  Furthermore, each entity has a mandatory "role"
   leaf (the local entity PCEP role).  The ietf-inet-types [RFC6991] is
   used.

   There is one list for configuration ("/pcep/entity"), and a separate
   list for the operational state of all entities ("/pcep-state/
   entity").

   The PCEP MIB module [RFC7420] uses a system generated entity index as
   a primary index to the read only entity table.  If the device
   implements the PCEP MIB, the "index" leaf MUST contain the value of
   the corresponding pcePcepEntityIndex.

5.2.  The Peer Lists

   The peer list contains peer(s) that the local PCEP entity knows
   about.  A PCEP speaker is identified by its IP address.  If there is
   a PCEP speaker in the network that uses multiple IP addresses then it
   looks like multiple distinct peers to the other PCEP speakers in the
   network.

   Since PCEP sessions can be ephemeral, the peer list tracks a peer
   even when no PCEP session currently exists to that peer.  The
   statistics contained are an aggregate of the statistics for all
   successive sessions to that peer.

   To limit the quantity of information that is stored, an
   implementation MAY choose to discard this information if and only if
   no PCEP session exists to the corresponding peer.






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   The data model for PCEP peer presented in this document uses a flat
   list of peers.  Each peer in the list is identified by its IP address
   (addr-type, addr).

   There is one list for static peer configuration ("/pcep/entity/
   peers"), and a separate list for the operational state of all peers
   (i.e.  static as well as discovered)("/pcep-state/entity/peers").

5.3.  The Session Lists

   The session list contains PCEP session that the PCEP entity (PCE or
   PCC) is currently participating in.  The statistics in session are
   semantically different from those in peer since the former applies to
   the current session only, whereas the latter is the aggregate for all
   sessions that have existed to that peer.

   Although [RFC5440] forbids more than one active PCEP session between
   a given pair of PCEP entities at any given time, there is a window
   during session establishment where two sessions may exist for a given
   pair, one representing a session initiated by the local PCEP entity
   and the other representing a session initiated by the peer.  If
   either of these sessions reaches active state first, then the other
   is discarded.

   The data model for PCEP session presented in this document uses a
   flat list of sessions.  Each session in the list is identified by its
   initiator.  This index allows two sessions to exist transiently for a
   given peer, as discussed above.

   There is only one list for the operational state of all sessions
   ("/pcep-state/entity/peers/peer/sessions/session").

5.4.  Notifications

   This YANG model defines a list of notifications to inform client of
   important events detected during the protocol operation.  The
   notifications defined cover the PCEP MIB notifications.

6.  Advanced PCE Features

   This document contains a specification of the base PCEP YANG module,
   "ietf-pcep" which provides the basic PCEP [RFC5440] data model.

   A means and procedure to handle to following PCE features needs to be
   decided:

   o  Capability and Scope




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   o  Domain information (local/neighbour)

   o  Path-Key

   o  OF

   o  GCO

   o  P2MP

   o  GMPLS

   o  Inter-Layer

   o  Stateful PCE

7.  PCEP YANG Module

   RFC Ed.: In this section, replace all occurrences of 'XXXX' with the
   actual RFC number and all occurrences of the revision date below with
   the date of RFC publication (and remove this note).


<CODE BEGINS> file "ietf-pcep@2015-02-xx.yang"






module ietf-pcep {
    namespace "urn:ietf:params:xml:ns:yang:ietf-pcep";
    prefix pcep;

    import ietf-inet-types {
        prefix inet;
    }

    import ietf-yang-types {
        prefix yang;
    }

    organization
        "IETF PCE (Path Computation Element) Working Group";

    contact
        "WG Web:   <http://tools.ietf.org/wg/pce/>
         WG List:  <mailto:pce@ietf.org>



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         WG Chair: JP Vasseur
                   <mailto:jpv@cisco.com>

         WG Chair: Julien Meuric
                   <mailto:julien.meuric@orange.com>

         Editor:   Dhruv Dhody
                   <mailto:dhruv.ietf@gmail.com>";

    description
        "The YANG module defines a generic configuration and
         operational model for PCEP common across all of the
         vendor implementations.";


    revision 2015-02-23 {
        description "Initial revision.";
        reference
            "RFC XXXX:  A YANG Data Model for Path Computation
                        Element Communications Protocol
                        (PCEP)";
    }

    /*
     * Identities
     */

    identity pcep {
        description "Identity for the PCEP protocol.";
    }

    /*
     * Typedefs
     */
    typedef pcep-role {
        type enumeration {
            enum unknown {
                value "0";
                description
                "An unknown role";
            }
            enum pcc {
                value "1";
                description
                "The role of a Path Computation Client";
            }
            enum pce {
                value "2";



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                description
                "The role of Path Computation Element";
            }
            enum pcc-and-pce {
                value "3";
                description
                "The role of both Path Computation Client and
                 Path Computation Element";
            }
        }

        description
            "The role of a PCEP speaker.
             Takes one of the following values
             - unknown(0): the role is not known.
             - pcc(1): the role is of a Path Computation
               Client (PCC).
             - pce(2): the role is of a Path Computation
               Server (PCE).
             - pccAndPce(3): the role is of both a PCC and
               a PCE.";

    }

    typedef pcep-admin-status {
        type enumeration {
                enum admin-status-up {
                value "1";
                description
                "Admin Status is Up";
            }
            enum admin-status-down {
                value "2";
                description
                "Admin Status is Down";
            }
        }

        description
        "The Admin Status of the PCEP entity.
         Takes one of the following values
             - admin-status-up(1): Admin Status is Up.
             - admin-status-down(2): Admin Status is Down";
    }

    typedef pcep-oper-status {
        type enumeration {
            enum oper-status-up {



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                value "1";
                description
                "The PCEP entity is active";
            }
            enum oper-status-down {
                value "2";
                description
                "The PCEP entity is inactive";
            }
            enum oper-status-going-up {
                value "3";
                description
                "The PCEP entity is activating";
            }
            enum oper-status-going-down {
                value "4";
                description
                "The PCEP entity is deactivating";
            }
            enum oper-status-failed {
                value "5";
                description
                "The PCEP entity has failed and will recover
                 when possible.";
            }
            enum oper-status-failed-perm {
                value "6";
                description
                "The PCEP entity has failed and will not recover
                 without operator intervention";
            }
        }
        description
        "The operational status of the PCEP entity.
         Takes one of the following values
             - oper-status-up(1): Active
             - oper-status-down(2): Inactive
             - oper-status-going-up(3): Activating
             - oper-status-going-down(4): Deactivating
             - oper-status-failed(5): Failed
             - oper-status-failed-perm(6): Failed Permanantly";
    }

    typedef pcep-initiator {
        type enumeration {
            enum local {
                value "1";
                description



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                "The local PCEP entity initiated the session";
            }

            enum remote {
                value "2";
                description
                "The remote PCEP peer initiated the session";
            }
        }
        description
        "The initiator of the session, that is, whether the TCP
         connection was initiated by the local PCEP entity or
         the remote peer.
         Takes one of the following values
             - local(1): Initiated locally
             - remote(2): Initiated remotely";
    }

    typedef pcep-sess-state {
        type enumeration {
            enum tcp-pending {
                value "1";
                description
                    "The tcp-pending state of PCEP session.";
            }

            enum open-wait {
                value "2";
                description
                    "The open-wait state of PCEP session.";
            }

            enum keep-wait {
                value "3";
                description
                    "The keep-wait state of PCEP session.";
            }

            enum session-up {
                value "4";
                description
                    "The session-up state of PCEP session.";
            }
        }
        description
            "The current state of the session.

             The set of possible states excludes the idle state



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             since entries do not exist in the idle state.
             Takes one of the following values
                - tcp-pending(1): PCEP TCP Pending state
                - open-wait(2): PCEP Open Wait state
                - keep-wait(3): PCEP Keep Wait state
                - session-up(4): PCEP Session Up state";
    }

    typedef pce-domain-type {
        type enumeration {
            enum ospf-area {
                value "1";
                description
                    "The OSPF area.";
            }
            enum isis-area {
                value "2";
                description
                    "The IS-IS area.";
            }
            enum as {
                value "3";
                description
                    "The Autonomous System (AS).";
            }
        }
        description
            "The PCE Domain Type";
    }

    typedef domain-ospf-area {
        type union {
            type uint32;
            type yang:dotted-quad;
       }
       description
            "OSPF Area ID.";
    }

    typedef domain-isis-area {
        type string {
            pattern '[0-9A-Fa-f]{2}\.([0-9A-Fa-f]{4}\.){0,3}';
        }
        description
            "IS-IS Area ID.";
    }

    typedef domain-as {



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        type uint32;
        description
            "Autonomous System number.";

    }

    typedef pce-domain {
        type union {
            type domain-ospf-area;
            type domain-isis-area;
            type domain-as;
        }
        description
            "The PCE Domain";
    }



    /*
     * Features - TBD
     */

    /*
     * Groupings
     */



    grouping pcep-entity-info{
        description
            "This grouping defines the attributes for PCEP entity.";
        leaf connect-timer {
            type uint32 {
                range "1..65535";
            }
            units "seconds";
            default 60;
            description
                "The time in seconds that the PCEP entity will wait
                 to establish a TCP connection with a peer.  If a
                 TCP connection is not established within this time
                 then PCEP aborts the session setup attempt.";
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }

        leaf connect-max-retry {



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            type uint32;
            default 5;
            description
                "The maximum number of times the system tries to
                 establish a TCP connection to a peer before the
                 session with the peer transitions to the idle
                 state.";
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }

        leaf init-backoff-timer {
            type uint32 {
                range "1..65535";
            }
            units "seconds";
            description
               "The initial back-off time in seconds for retrying
                a failed session setup attempt to a peer.

                The back-off time increases for each failed
                session setup attempt, until a maximum back-off
                time is reached.  The maximum back-off time is
                max-backoff-timer.";
        }

        leaf max-backoff-timer {
            type uint32;
            units "seconds";
            description
               "The maximum back-off time in seconds for retrying
                a failed session setup attempt to a peer.

                The back-off time increases for each failed session
                setup attempt, until this maximum value is reached.
                Session setup attempts then repeat periodically
                without any further increase in back-off time.";
        }

        leaf open-wait-timer {
            type uint32 {
                range "1..65535";
            }
            units "seconds";
            default 60;
            description
               "The time in seconds that the PCEP entity will wait



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                to receive an Open message from a peer after the
                TCP connection has come up.

                If no Open message is received within this time then
                PCEP terminates the TCP connection and deletes the
                associated sessions.";
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }

        leaf keep-wait-timer {
            type uint32 {
                range "1..65535";
            }
            units "seconds";
            default 60;
            description
                "The time in seconds that the PCEP entity will wait
                 to receive a Keepalive or PCErr message from a peer
                 during session initialization after receiving an
                 Open message.  If no Keepalive or PCErr message is
                 received within this time then PCEP terminates the
                 TCP connection and deletes the associated
                 sessions.";
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }

        leaf keep-alive-timer {
            type uint32 {
                range "0..255";
            }
            units "seconds";
            default 30;
            description
                "The keep alive transmission timer that this PCEP
                 entity will propose in the initial OPEN message of
                 each session it is involved in.  This is the
                 maximum time between two consecutive messages sent
                 to a peer. Zero means that the PCEP entity prefers
                 not to send Keepalives at all.

                 Note that the actual Keepalive transmission
                 intervals, in either direction of an active PCEP
                 session, are determined by negotiation between the
                 peers as specified by RFC 5440, and so may differ



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                 from this configured value.";
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }

        leaf dead-timer {
            type uint32 {
                range "0..255";
            }
            units "seconds";
            must ". >= ../keep-alive-timer" {
                error-message "The dead timer must be "
                       + "larger than the keep alive timer";
                description
                    "This value MUST be greater than
                     keep-alive-timer.";

            }
            default 120;
            description
                "The dead timer that this PCEP entity will propose
                 in the initial OPEN message of each session it is
                 involved in. This is the time after which a peer
                 should declare a session down if it does not
                 receive any PCEP messages. Zero suggests that the
                 peer does not run a dead timer at all." ;
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }

        leaf allow-negotiation{
            type boolean;
            description
                "Whether the PCEP entity will permit negotiation of
                 session parameters.";
        }

        leaf max-keep-alive-timer{
            type uint32 {
                range "0..255";
            }
            units "seconds";
            description
                "In PCEP session parameter negotiation in seconds,
                 the maximum value that this PCEP entity will
                 accept from a peer for the interval between



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                 Keepalive transmissions. Zero means that the PCEP
                 entity will allow no Keepalive transmission at
                 all." ;
        }

        leaf max-dead-timer{
            type uint32 {
                range "0..255";
            }
            units "seconds";
            description
                "In PCEP session parameter negotiation in seconds,
                 the maximum value that this PCEP entity will accept
                 from a peer for the Dead timer.  Zero means that
                 the PCEP entity will allow not running a Dead
                 timer.";
        }

        leaf min-keep-alive-timer{
            type uint32 {
                range "0..255";
            }
            units "seconds";
            description
                "In PCEP session parameter negotiation in seconds,
                 the minimum value that this PCEP entity will
                 accept for the interval between Keepalive
                 transmissions. Zero means that the PCEP entity
                 insists on no Keepalive transmission at all.";
        }

        leaf min-dead-timer{
            type uint32 {
                range "0..255";
            }
            units "seconds";
            description
                 "In PCEP session parameter negotiationin in
                  seconds, the minimum value that this PCEP entity
                  will accept for the Dead timer.  Zero means that
                  the PCEP entity insists on not running a Dead
                  timer.";
        }

        leaf sync-timer{
            type uint32 {
                range "0..65535";
            }



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            units "seconds";
            default 60;
            description
                "The value of SyncTimer in seconds is used in the
                 case of synchronized path computation request
                 using the SVEC object. Consider the case where a
                 PCReq message is received by a PCE that contains
                 the SVEC object referring to M synchronized path
                 computation requests.  If after the expiration of
                 the SyncTimer all the M path computation requests
                 have not been, received a protocol error is
                 triggered and the PCE MUST cancel the whole set
                 of path computation  requests.

                 The aim of the SyncTimer is to avoid the storage
                 of unused synchronized requests should one of
                 them get lost for some reasons (for example, a
                 misbehaving PCC).

                 Zero means that the PCEP entity does not use the
                 SyncTimer.";
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }

        leaf request-timer{
            type uint32 {
                range "1..65535";
            }
            units "seconds";
            description
                "The maximum time that the PCEP entity will wait
                 for a response to a PCReq message.";
        }

        leaf max-sessions{
            type uint32;
            description
               "Maximum number of sessions involving this PCEP
                entity that can exist at any time.";
        }

        leaf max-unknown-reqs{
            type uint32;
            default 5;
            description
              "The maximum number of unrecognized requests and



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               replies that any session on this PCEP entity is
               willing to accept per minute before terminating
               the session.

               A PCRep message contains an unrecognized reply
               if it contains an RP object whose request ID
               does not correspond to any in-progress request
               sent by this PCEP entity.

               A PCReq message contains an unrecognized request
               if it contains an RP object whose request ID is
               zero.";
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }

        leaf max-unknown-msgs{
            type uint32;
            default 5;
            description
             "The maximum number of unknown messages that any
              session on this PCEP entity is willing to accept
              per minute before terminating the session.";
            reference
                "RFC 5440: Path Computation Element (PCE)
                           Communication Protocol (PCEP)";
        }
    }//pcep-entity-info

    grouping  pce-scope{
        description
            "This grouping defines PCE path computation scope
             information which maybe relevant to PCE selection.
             This information corresponds to PCE auto-discovery
             information.";
        reference
            "RFC 5088: OSPF Protocol Extensions for Path
                       Computation Element (PCE)
                       Discovery
             RFC 5089: IS-IS Protocol Extensions for Path
                       Computation Element (PCE)
                       Discovery";
        leaf intra-area-scope{
            type boolean;
            default true;
            description
                "PCE can compute intra-area paths.";



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        }
        leaf intra-area-pref{
            type uint8{
                range "0..7";
            }
            description
              "The PCE's preference for intra-area TE LSP
              computation.";
        }
        leaf inter-area-scope{
            type boolean;
            default false;
            description
                "PCE can compute inter-area paths.";
        }
        leaf inter-area-scope-default{
            type boolean;
            default false;
            description
                "PCE can act as a default PCE for inter-area
                 path computation.";
        }
        leaf inter-area-pref{
            type uint8{
                range "0..7";
            }
            description
              "The PCE's preference for inter-area TE LSP
              computation.";
        }
        leaf inter-as-scope{
            type boolean;
            default false;
            description
                "PCE can compute inter-AS paths.";
        }
        leaf inter-as-scope-default{
            type boolean;
            default false;
            description
                "PCE can act as a default PCE for inter-AS
                 path computation.";
        }
        leaf inter-as-pref{
            type uint8{
                range "0..7";
            }
            description



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              "The PCE's preference for inter-AS TE LSP
              computation.";
        }
        leaf inter-layer-scope{
            type boolean;
            default false;
            description
                "PCE can compute inter-layer paths.";
        }
        leaf inter-layer-pref{
            type uint8{
                range "0..7";
            }
            description
              "The PCE's preference for inter-layer TE LSP
              computation.";
        }
    }//pce-scope

    grouping  pce-domain{
        description
            "This grouping specifies a PCE-Domain where the
             PCE has topology visibility and through which
             the PCE can compute paths.";
        leaf domain-type{
            type pce-domain-type;
            description
              "The PCE domain type.";
        }
        leaf domain{
            type pce-domain;
            description
              "The PCE domain.";
        }
    }//pce-domain

    grouping  pce-capability{
        description
            "This grouping specifies a PCE-capability
             information which maybe relevant to PCE selection.
             This information corresponds to PCE auto-discovery
             information.";
        reference
            "RFC 5088: OSPF Protocol Extensions for Path
                       Computation Element (PCE)
                       Discovery
             RFC 5089: IS-IS Protocol Extensions for Path
                       Computation Element (PCE)



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                       Discovery";
        leaf gmpls{
            type boolean;
            description
              "Path computation with GMPLS link
               constraints.";
        }
        leaf bi-dir{
            type boolean;
            description
              "Bidirectional path computation.";
        }
        leaf diverse{
            type boolean;
            description
              "Diverse path computation.";
        }
        leaf load-balance{
            type boolean;
            description
              "Load-balanced path computation.";
        }
        leaf synchronize{
            type boolean;
            description
              "Synchronized paths computation.";
        }
        leaf objective-function{
            type boolean;
            description
              "Support for multiple objective functions.";
        }
        leaf add-path-constraint{
            type boolean;
            description
              "Support for additive path constraints (max
               hop count, etc.).";
        }
        leaf prioritization{
            type boolean;
            description
              "Support for request prioritization.";
        }
        leaf multi-request{
            type boolean;
            description
              "Support for multiple requests per message.";
        }



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        leaf gco{
            type boolean;
            description
              "Support for Global Concurrent Optimization
               (GCO).";
        }
        leaf p2mp{
            type boolean;
            description
              "Support for P2MP path computation.";
        }
    }//pce-capability

    grouping  pce-info{
        description
            "This grouping specifies all PCE information
             which maybe relevant to the PCE selection.
             This information corresponds to PCE auto-discovery
             information.";
        container scope{
            description
                "The path computation scope";
            uses pce-scope;
        }
        container domain{
            description
                "The PCE domain";
            uses pce-domain{
                description
                    "The PCE local domain.";
            }
        }
        container neigh-domains{
            description
                "The list of neighbour PCE-Domain
                 toward which a PCE can compute
                 paths";
            list domain{
                key "domain-type domain";

                description
                    "The neighbour domain.";
                uses pce-domain{
                    description
                        "The PCE neighbour domain.";
                }
            }
        }



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        container capability{
            description
                "The PCE capability";
            uses pce-capability{
                description
                    "The PCE entity supported
                    capabilities.";
            }
        }
    }//pce-info

    grouping  pcep-stats{
        description
            "This grouping defines statistics for PCEP. It is used
             for both peer and current session.";
        leaf avg-rsp-time{
            type uint32;
            units "milliseconds";
            must "(/pcep-state/entity/peers/peer/role != 'pcc'" +
                 " or " +
                 "(/pcep-state/entity/peers/peer/role = 'pcc'" +
                 " and avg-rsp-time = 0))" {
                error-message
                    "Invalid average response time";
                description
                    "If role is pcc then this leaf is meaningless
                     and is set to zero.";
            }
            description
              "The average response time.

               If an average response time has not been
               calculated then this leaf has the value zero.";
        }

        leaf lwm-rsp-time{
            type uint32;
            units "milliseconds";
            must "(/pcep-state/entity/peers/peer/role != 'pcc'" +
                 " or " +
                 "(/pcep-state/entity/peers/peer/role = 'pcc'" +
                 " and lwm-rsp-time = 0))" {
                error-message
                    "Invalid smallest (low-water mark)
                     response time";
                description
                    "If role is pcc then this leaf is meaningless
                     and is set to zero.";



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            }
            description
             "The smallest (low-water mark) response time seen.

              If no responses have been received then this
              leaf has the value zero.";
        }

        leaf hwm-rsp-time{
            type uint32;
            units "milliseconds";
            must "(/pcep-state/entity/peers/peer/role != 'pcc'" +
                 " or " +
                 "(/pcep-state/entity/peers/peer/role = 'pcc'" +
                 " and hwm-rsp-time = 0))" {
                error-message
                    "Invalid greatest (high-water mark)
                     response time seen";
                description
                    "If role is pcc then this field is
                     meaningless and is set to zero.";
            }
            description
             "The greatest (high-water mark) response time seen.

              If no responses have been received then this object
              has the value zero.";
        }

        leaf num-pcreq-sent{
            type yang:counter32;
            description
             "The number of PCReq messages sent.";
        }

        leaf num-pcreq-rcvd{
            type yang:counter32;
            description
              "The number of PCReq messages received.";
        }

        leaf num-pcrep-sent{
            type yang:counter32;
            description
              "The number of PCRep messages sent.";
        }

        leaf num-pcrep-rcvd{



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            type yang:counter32;
            description
              "The number of PCRep messages received.";
        }

        leaf num-pcerr-sent{
            type yang:counter32;
            description
              "The number of PCErr messages sent.";
        }

        leaf num-pcerr-rcvd{
            type yang:counter32;
            description
              "The number of PCErr messages received.";
        }

        leaf num-pcntf-sent{
            type yang:counter32;
            description
              "The number of PCNtf messages sent.";
        }

        leaf num-pcntf-rcvd{
            type yang:counter32;
            description
              "The number of PCNtf messages received.";
        }

        leaf num-keepalive-sent{
            type yang:counter32;
            description
              "The number of Keepalive messages sent.";
        }

        leaf num-keepalive-rcvd{
            type yang:counter32;
            description
              "The number of Keepalive messages received.";
        }

        leaf num-unknown-rcvd{
            type yang:counter32;
            description
              "The number of unknown messages received.";
        }

        leaf num-corrupt-rcvd{



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            type yang:counter32;
            description
              "The number of corrupted PCEP message received.";
        }

        leaf num-req-sent{
            type yang:counter32;
            description
              "The number of requests sent.  A request corresponds
               1:1 with an RP object in a PCReq message. This might
               be greater than num-pcreq-sent because multiple
               requests can be batched into a single PCReq
               message.";
        }

        leaf num-svec-sent{
            type yang:counter32;
            description
              "The number of SVEC objects sent in PCReq messages.
               An SVEC object represents a set of synchronized
               requests.";
        }

        leaf num-svec-req-sent{
            type yang:counter32;
            description
              "The number of requests sent that appeared in one
               or more SVEC objects.";
        }

        leaf num-req-sent-pend-rep{
            type yang:counter32;
            description
              "The number of requests that have been sent for
               which a response is still pending.";
        }

        leaf num-req-sent-ero-rcvd{
            type yang:counter32;
            description
               "The number of requests that have been sent for
                which a response with an ERO object was received.
                Such responses indicate that a path was
                successfully computed by the peer.";
        }

        leaf num-req-sent-nopath-rcvd{
            type yang:counter32;



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            description
              "The number of requests that have been sent for
               which a response with a NO-PATH object was
               received. Such responses indicate that the peer
               could not  find a path to satisfy the
               request.";
        }

        leaf num-req-sent-cancel-rcvd{
            type yang:counter32;
            description
              "The number of requests that were cancelled with
               a PCNtf message.

               This might be different than num-pcntf-rcvd because
               not all PCNtf messages are used to cancel requests,
               and a single PCNtf message can cancel multiple
               requests.";
        }

        leaf num-req-sent-error-rcvd{
            type yang:counter32;
            description
             "The number of requests that were rejected with a
              PCErr message.

              This might be different than num-pcerr-rcvd because
              not all PCErr messages are used to reject requests,
              and a single PCErr message can reject multiple
              requests.";
        }

        leaf num-req-sent-timeout{
            type yang:counter32;
            description
             "The number of requests that have been sent to a peer
             and have been abandoned because the peer has taken too
             long to respond to them.";
        }

        leaf num-req-sent-cancel-sent{
            type yang:counter32;
            description
             "The number of requests that were sent to the peer and
              explicitly cancelled by the local PCEP entity sending
              a PCNtf.";
        }




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        leaf num-req-rcvd{
            type yang:counter32;
            description
             "The number of requests received.  A request
              corresponds 1:1 with an RP object in a PCReq
              message.

              This might be greater than num-pcreq-rcvd because
              multiple requests can be batched into a single
              PCReq message.";
        }

        leaf num-svec-rcvd{
            type yang:counter32;
            description
             "The number of SVEC objects received in PCReq
              messages. An SVEC object represents a set of
              synchronized requests.";
        }

        leaf num-svec-req-rcvd{
            type yang:counter32;
            description
              "The number of requests received that appeared in one
               or more SVEC objects.";
        }

        leaf num-req-rcvd-pend-rep{
            type yang:counter32;
            description
             "The number of requests that have been received for
              which a response is still pending.";
        }

        leaf num-req-rcvd-ero-sent{
            type yang:counter32;
            description
             "The number of requests that have been received for
              which a response with an ERO object was sent.  Such
              responses indicate that a path was successfully
              computed by the local PCEP entity.";
        }

        leaf num-req-rcvd-nopath-sent{
            type yang:counter32;
            description
             "The number of requests that have been received for
              which a response with a NO-PATH object was sent. Such



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              responses indicate that the local PCEP entity could
              not find a path to satisfy the request.";
        }

        leaf num-req-rcvd-cancel-sent{
            type yang:counter32;
            description
             "The number of requests received that were cancelled
              by the local PCEP entity sending a PCNtf message.

              This might be different than num-pcntf-sent because
              not all PCNtf messages are used to cancel requests,
              and a single PCNtf message can cancel multiple
              requests.";
        }

        leaf num-req-rcvd-error-sent{
            type yang:counter32;
            description
             "The number of requests received that were cancelled
              by the local PCEP entity sending a PCErr message.

              This might be different than num-pcerr-sent because
              not all PCErr messages are used to cancel requests,
              and a single PCErr message can cancel multiple
              requests.";
        }

        leaf  num-req-rcvd-cancel-rcvd{
            type yang:counter32;
            description
             "The number of requests that were received from the
              peer and explicitly cancelled by the peer sending
              a PCNtf.";
        }

        leaf  num-rep-rcvd-unknown{
            type yang:counter32;
            description
              "The number of responses to unknown requests
               received. A response to an unknown request is a
               response whose RP object does not contain the
               request ID of any request that is currently
               outstanding on the session.";
        }

        leaf  num-req-rcvd-unknown{
            type yang:counter32;



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            description
              "The number of unknown requests that have been
               received. An unknown request is a request
               whose RP object contains a request ID of
               zero.";
        }

    }//pcep-stats

    grouping notification-instance-hdr {
        description
            "This group describes common instance specific data
             for notifications.";

        leaf entity-addr {
            type leafref {
                path "/pcep-state/entity/addr";
            }
            description
                "Reference to local entity address";
        }

        leaf peer-addr {
            type leafref {
                path "/pcep-state/entity/peers/peer/addr";
            }
            description
                "Reference to peer address";
        }

    }// notification-instance-hdr

    grouping notification-session-hdr {
        description
        "This group describes common session instance specific
         data for notifications.";

        leaf session-initiator {
            type leafref {
            path "/pcep-state/entity/peers/peer/sessions/" +
                 "session/initiator";
            }
            description
                "Reference to pcep session initiator leaf";
        }
    }// notification-session-hdr

    /*



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     * Configuration data nodes
     */
    container pcep{

        description
            "Parameters for list of configured PCEP entities
             on the device.";

        list entity{
            key "addr";

            description
                "The configured PCEP entity on the device.";

            leaf addr {
                type inet:ip-address;
                description
                    "The local Internet address of this PCEP
                    entity.

                    If operating as a PCE server, the PCEP
                    entity listens on this address.

                    If operating as a PCC, the PCEP entity
                    binds outgoing TCP connections to this
                    address.

                    It is possible for the PCEP entity to
                    operate both as a PCC and a PCE Server, in
                    which case it uses this address both to
                    listen for incoming TCP connections and to
                    bind outgoing TCP connections.";
            }

            leaf enabled {
                type boolean;
                default true;
                description
                    "The administrative status of this PCEP
                     Entity.";
            }

            leaf role {
                type pcep-role;
                mandatory true;
                description
                    "The role that this entity can play.
                     Takes one of the following values.



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                     - unknown(0): this PCEP Entity role is not
                       known.
                     - pcc(1): this PCEP Entity is a PCC.
                     - pce(2): this PCEP Entity is a PCE.
                     - pcc-and-pce(3): this PCEP Entity is both
                       a PCC and a PCE.";
            }

            leaf description {
                type string;
                description
                    "Description of the PCEP entity configured
                     by the user";
            }

            container pce-info {
                must "((../role == 'pce')" +
                     " or " +
                     "(../role == 'pcc-and-pce'))"
                {
                    error-message "The PCEP entity must be PCE";
                    description
                        "When PCEP entity is PCE";
                }
                uses pce-info {
                    description
                        "Local PCE information";
                }
                description
                    "The Local PCE Entity PCE information";
            }

            uses pcep-entity-info {
                description
                    "The configuration related to the PCEP
                     entity.";
            }



            leaf pcep-notification-max-rate {
                type uint32;
                mandatory true;
                description
                    "This variable indicates the maximum number of
                     notifications issued per second. If events occur
                     more rapidly, the implementation may simply fail
                     to emit these notifications during that period,



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                     or may queue them until an appropriate time. A
                     value of 0 means no notifications are emitted
                     and all should be discarded (that is, not
                     queued).";
            }

            container peers{
                description
                        "The list of configured peers for the
                         entity";

                list peer{
                    key "addr";

                    description
                        "The peer configured for the entity.";

                    leaf addr {
                        type inet:ip-address;
                        description
                            "The local Internet address of this PCEP peer.";
                    }

                     leaf description {
                        type string;
                        description
                            "Description of the PCEP peer
                             configured by the user";
                    }
                    container pce-info {
                        uses pce-info {
                            description
                                "PCE Peer information";
                        }
                    description
                        "The Local PCE Entity PCE information";
                    }
                }//peer
            }//peers
        }//entity
    }//pcep

    /*
     * Operational data nodes
     */

    container pcep-state{
        config false;



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        description
            "The list of operational PCEP entities on the
             device.";

        list entity{
            key "addr";
            unique "index";

            description
                "The operational PCEP entity on the device.";

            leaf index{
                type uint32;
                description
                    "The index of the operational PECP
                     entity";
            }

            leaf addr {
                type inet:ip-address;
                description
                    "The local Internet address of this PCEP
                    entity.

                    If operating as a PCE server, the PCEP
                    entity listens on this address.

                    If operating as a PCC, the PCEP entity
                    binds outgoing TCP connections to this
                    address.

                    It is possible for the PCEP entity to
                    operate both as a PCC and a PCE Server, in
                    which case it uses this address both to
                    listen for incoming TCP connections and to
                    bind outgoing TCP connections.";
            }

            leaf admin-status {
                type pcep-admin-status;
                description
                    "The administrative status of this PCEP Entity.
                     This is the desired operational status as
                     currently set by an operator or by default in
                     the implementation.  The value of enabled
                     represents the current status of an attempt
                     to reach this desired status.";
            }



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            leaf oper-status {
                type pcep-admin-status;
                description
                   "The operational status of the PCEP entity.
                    Takes one of the following values.
                    - oper-status-up(1): the PCEP entity is
                      active.
                    - oper-status-down(2): the PCEP entity is
                      inactive.
                    - oper-status-going-up(3): the PCEP entity is
                      activating.
                    - oper-status-going-down(4): the PCEP entity is
                      deactivating.
                    - oper-status-failed(5): the PCEP entity has
                      failed and will recover when possible.
                    - oper-status-failed-perm(6): the PCEP entity
                      has failed and will not recover without
                      operator intervention.";
            }

            leaf role {
                type pcep-role;
                description
                    "The role that this entity can play.
                     Takes one of the following values.
                     - unknown(0): this PCEP entity role is
                       not known.
                     - pcc(1): this PCEP entity is a PCC.
                     - pce(2): this PCEP entity is a PCE.
                     - pcc-and-pce(3): this PCEP entity is
                       both a PCC and a PCE.";
            }

            container pce-info {
                when "((../role == 'pce')" +
                     " or " +
                     "(../role == 'pcc-and-pce'))"
                {
                    description
                        "When PCEP entity is PCE";
                }
                uses pce-info {
                    description
                        "Local PCE information";
                }
                description
                    "The Local PCE Entity PCE information";
            }



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            uses pcep-entity-info{
                description
                    "The operational information related to the
                     PCEP entity.";
            }



            container peers{
                description
                        "The list of peers for the entity";

                list peer{
                    key "addr";

                    description
                        "The peer for the entity.";

                    leaf addr {
                        type inet:ip-address;
                        description
                            "The local Internet address of this PCEP peer.";
                    }

                    leaf role {
                        type pcep-role;
                        description
                            "The role of the PCEP Peer.
                             Takes one of the following values.
                             - unknown(0): this PCEP peer role
                               is not known.
                             - pcc(1): this PCEP peer is a PCC.
                             - pce(2): this PCEP peer is a PCE.
                             - pcc-and-pce(3): this PCEP peer
                               is both a PCC and a PCE.";
                    }

                    container pce-info {
                        uses pce-info {
                            description
                                "PCE Peer information";
                        }
                    description
                        "The Local PCE Entity PCE information";
                    }

                    leaf discontinuity-time {
                        type yang:timestamp;



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                        description
                            "The timestamp of the time when the
                             information and statistics were
                             last reset.";
                    }

                    leaf initiate-session {
                        type boolean;
                        description
                            "Indicates whether the local PCEP
                             entity initiates sessions to this peer,
                             or waits for the peer to initiate a
                             session.";
                    }

                    leaf session-exists{
                        type boolean;
                        description
                            "Indicates whether a session with
                             this peer currently exists.";
                    }

                    leaf num-sess-setup-ok{
                        type yang:counter32;
                        description
                            "The number of PCEP sessions successfully
                             successfully established with the peer,
                             including any current session.  This
                             counter is incremented each time a
                             session with this peer is successfully
                             established.";
                    }

                    leaf num-sess-setup-fail{
                        type yang:counter32;
                        description
                           "The number of PCEP sessions with the peer
                            that have been attempted but failed
                            before being fully established. This
                            counter is incremented each time a
                            session retry to this peer fails.";
                    }

                    leaf session-up-time{
                        type yang:timestamp;
                        must "(../num-sess-setup-ok != 0  or " +
                            "(../num-sess-setup-ok = 0  and "  +
                            "session-up-time = 0))" {



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                                error-message
                                    "Invalid Session Up timestamp";
                                description
                                    "If num-sess-setup-ok is zero,
                                     then this leaf contains zero.";
                            }
                        description
                           "The timestamp value of the last time a
                            session with this peer was successfully
                            established.";
                    }

                    leaf session-fail-time{
                        type yang:timestamp;
                        must "(../num-sess-setup-fail != 0  or " +
                            "(../num-sess-setup-fail = 0  and "  +
                            "session-fail-time = 0))" {
                                error-message
                                    "Invalid Session Fail timestamp";
                                description
                                    "If num-sess-setup-fail is zero,
                                     then this leaf contains zero.";
                            }
                        description
                          "The timestamp value of the last time a
                           session with this peer failed to be
                           established.";
                    }

                    leaf session-fail-up-time{
                        type yang:timestamp;
                        must "(../num-sess-setup-ok != 0  or "     +
                            "(../num-sess-setup-ok = 0  and "     +
                            "session-fail-up-time = 0))" {
                                error-message
                                    "Invalid Session Fail from
                                     Up timestamp";
                                description
                                    "If num-sess-setup-ok is zero,
                                     then this leaf contains zero.";
                            }
                        description
                          "The timestamp value of the last time a
                           session with this peer failed from
                           active.";
                    }

                    uses pcep-stats{



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                        description
                            "Since PCEP sessions can be ephemeral,
                             the peer statistics tracks a peer even
                             when no PCEP session currently exists
                             to that peer. The statistics contained
                             are an aggregate of the statistics for
                             all successive sessions to that peer.";
                    }

                    leaf num-req-sent-closed{
                        type yang:counter32;
                        description
                            "The number of requests that were sent
                             to the peer and implicitly cancelled
                             when the session they were sent over
                             was closed.";
                    }

                    leaf  num-req-rcvd-closed{
                        type yang:counter32;
                        description
                            "The number of requests that were
                             received from the peer and implicitly
                             cancelled when the session they were
                             received over was closed.";
                    }

                    container sessions {
                        description
                            "This entry represents a single PCEP
                             session in which the local PCEP entity
                             participates.

                             This entry exists only if the
                             corresponding PCEP session has been
                             initialized by some event, such as
                             manual user configuration, auto-
                             discovery of a peer, or an incoming
                             TCP connection.";

                        list session {
                            key "initiator";

                            description
                                "The list of sessions, note that
                                 for a time being two sessions
                                 may exist for a peer";




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                            leaf initiator {
                                type pcep-initiator;
                                description
                                    "The initiator of the session,
                                     that is, whether the TCP
                                     connection was initiated by
                                     the local PCEP entity or the
                                     peer.

                                     There is a window during
                                     session initialization where
                                     two sessions can exist between
                                     a pair of PCEP speakers, each
                                     initiated by one of the
                                     speakers. One of these
                                     sessions is always discarded
                                     before it leaves OpenWait state.
                                     However, before it is discarded,
                                     two sessions to the given peer
                                     appear transiently in this MIB
                                     module. The sessions are
                                     distinguished by who initiated
                                     them, and so this field is the
                                     key.";
                            }

                            leaf state-last-change {
                                type yang:timestamp;
                                description
                                    "The timestamp value at the
                                     time this session entered its
                                     current state as denoted by
                                     the state leaf.";
                            }

                            leaf state {
                                type pcep-sess-state;
                                description
                                    "The current state of the
                                     session.

                                     The set of possible states
                                     excludes the idle state since
                                     entries do not exist in the
                                     idle state.";
                            }

                            leaf connect-retry {



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                                type yang:counter32;
                                description
                                     "The number of times that the
                                      local PCEP entity has
                                      attempted to establish a TCP
                                      connection for this session
                                      without success. The PCEP
                                      entity gives up when this
                                      reaches connect-max-retry.";
                            }

                            leaf local-id {
                                type uint32 {
                                  range "0..255";
                                }
                                description
                                     "The value of the PCEP session
                                      ID used by the local PCEP
                                      entity in the Open message
                                      for this session.

                                      If state is tcp-pending then
                                      this is the session ID that
                                      will be used in the Open
                                      message. Otherwise, this is
                                      the session ID that was sent
                                      in the Open message.";
                            }

                            leaf remote-id {
                                type uint32 {
                                    range "0..255";
                                }
                                must "((../state != 'tcp-pending'" +
                                     "and " +
                                     "../state != 'open-wait' )" +
                                     "or " +
                                     "((../state = 'tcp-pending'" +
                                     " or " +
                                     "../state = 'open-wait' )" +
                                     "and remote-id = 0))" {
                                        error-message
                                            "Invalid remote-id";
                                        description
                                             "If state is tcp-pending
                                              or open-wait then this
                                              leaf is not used and
                                              MUST be set to zero.";



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                                    }
                                description
                                     "The value of the PCEP session
                                      ID used by the peer in its
                                      Open message for this
                                      session.";
                            }

                            leaf keepalive-timer {
                                type uint32 {
                                  range "0..255";
                                }
                                units "seconds";
                                must "(../state = 'session-up'" +
                                     "or " +
                                     "(../state != 'session-up'" +
                                     "and keepalive-timer = 0))" {
                                        error-message
                                            "Invalid keepalive
                                             timer";
                                        description
                                            "This field is used if
                                             and only if state is
                                             session-up. Otherwise,
                                             it is not used and
                                             MUST be set to
                                             zero.";
                                    }
                                description
                                     "The agreed maximum interval at
                                      which the local PCEP entity
                                      transmits PCEP messages on this
                                      PCEP session.  Zero means that
                                      the local PCEP entity never
                                      sends Keepalives on this
                                      session.";
                            }

                            leaf peer-keepalive-timer {
                                type uint32 {
                                  range "0..255";
                                }
                                units "seconds";
                                must "(../state = 'session-up'" +
                                     "or "   +
                                     "(../state != 'session-up'" +
                                     "and " +
                                     "peer-keepalive-timer = 0))" {



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                                        error-message
                                            "Invalid Peer keepalive
                                             timer";
                                        description
                                            "This field is used if
                                             and only if state is
                                             session-up. Otherwise,
                                             it is not used and MUST
                                             be set to zero.";
                                    }
                                description
                                     "The agreed maximum interval at
                                      which the peer transmits PCEP
                                      messages on this PCEP session.
                                      Zero means that the peer never
                                      sends Keepalives on this
                                      session.";
                            }

                            leaf dead-timer {
                                type uint32 {
                                  range "0..255";
                                }
                                units "seconds";
                                description
                                     "The dead timer interval for
                                      this PCEP session.";
                            }

                            leaf peer-dead-timer {
                                type uint32 {
                                  range "0..255";
                                }
                                units "seconds";
                                must "((../state != 'tcp-pending'" +
                                     "and " +
                                     "../state != 'open-wait' )" +
                                     "or " +
                                     "((../state = 'tcp-pending'" +
                                     " or " +
                                     "../state = 'open-wait' )" +
                                     "and " +
                                     "peer-dead-timer = 0))" {
                                        error-message
                                            "Invalid Peer Dead
                                             timer";
                                        description
                                            "If state is tcp-



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                                             pending or open-wait
                                             then this leaf is not
                                             used and MUST be set to
                                             zero.";
                                    }
                                description
                                     "The peer's dead-timer interval
                                      for this PCEP session.";
                            }

                            leaf ka-hold-time-rem {
                                type uint32 {
                                  range "0..255";
                                }
                                units "seconds";
                                must "((../state != 'tcp-pending'" +
                                     "and " +
                                     "../state != 'open-wait' ) " +
                                     "or " +
                                     "((../state = 'tcp-pending'" +
                                     "or " +
                                     "../state = 'open-wait' )" +
                                     "and " +
                                     "ka-hold-time-rem = 0))" {
                                        error-message
                                            "Invalid Keepalive hold
                                             time remaining";
                                        description
                                            "If state is tcp-pending
                                             or open-wait then this
                                             field is not used and
                                             MUST be set to zero.";
                                    }
                                description
                                     "The keep alive hold time
                                      remaining for this session.";
                            }

                            leaf overloaded {
                                type boolean;
                                description
                                     "If the local PCEP entity has
                                      informed the peer that it is
                                      currently overloaded, then this
                                      is set to true.  Otherwise, it
                                      is set to false.";
                            }




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                            leaf overload-time {
                                type uint32;
                                units "seconds";
                                must "(../overloaded = true or" +
                                    "(../overloaded != true and" +
                                    " overload-time = 0))" {
                                        error-message
                                            "Invalid overload-time";
                                        description
                                            "This field is only used
                                             if overloaded is set to
                                             true. Otherwise, it is
                                             not used and MUST be set
                                             to zero.";
                                    }
                                description
                                     "The interval of time that is
                                      remaining until the local PCEP
                                      entity will cease to be
                                      overloaded on this session.";
                            }

                            leaf peer-overloaded {
                                type boolean;
                                description
                                     "If the peer has informed the
                                      local PCEP entity that it is
                                      currently overloaded, then this
                                      is set to true. Otherwise, it
                                      is set to false.";
                            }

                            leaf peer-overload-time {
                                type uint32;
                                units "seconds";
                                must "(../peer-overloaded = true" +
                                     " or " +
                                     "(../peer-overloaded != true" +
                                     " and " +
                                     "peer-overload-time = 0))" {
                                        error-message
                                            "Invalid peer overload
                                             time";
                                        description
                                            "This field is only used
                                             if peer-overloaded is
                                             set to true. Otherwise,
                                             it is not used and MUST



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                                             be set to zero.";
                                    }
                                description
                                     "The interval of time that is
                                      remaining until the peer will
                                      cease to be overloaded.  If it
                                      is not known how long the peer
                                      will stay in overloaded state,
                                      this leaf is set to zero.";
                            }

                            leaf discontinuity-time {
                                type yang:timestamp;
                                description
                                     "The timestamp value of the time
                                      when the statistics were last
                                      reset.";
                            }

                            uses pcep-stats{
                                description
                                    "The statistics contained are
                                     for the current sessions to that
                                     peer. These are lost when the
                                     session goes down.";

                            }

                        } // session
                    } // sessions
                }//peer
            }//peers
        }//entity
    }//pcep-state

    /*
     * Notifications
     */
    notification pcep-session-up {
        description
            "This notification is sent when the value of
             '/pcep/pcep-state/peers/peer/sessions/session/state'
             enters the 'session-up' state.";

        uses notification-instance-hdr;

        uses notification-session-hdr;




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        leaf state-last-change {
            type yang:timestamp;
            description
                "The timestamp value at the time this session entered
                its current state as denoted by the state leaf.";
        }

        leaf state {
            type pcep-sess-state;
            description
                "The current state of the session.

                 The set of possible states excludes the idle state
                 since entries do not exist in the idle state.";
        }
    } //notification

    notification pcep-session-down {
        description
            "This notification is sent when the value of
             '/pcep/pcep-state/peers/peer/sessions/session/state'
             leaves the 'session-up' state.";

        uses notification-instance-hdr;

        leaf session-initiator {
            type pcep-initiator;
            description
                "The initiator of the session.";
        }

        leaf state-last-change {
            type yang:timestamp;
            description
                "The timestamp value at the time this session entered
                its current state as denoted by the state leaf.";
        }

        leaf state {
            type pcep-sess-state;
            description
                "The current state of the session.

                 The set of possible states excludes the idle state
                 since entries do not exist in the idle state.";
        }
    } //notification




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    notification pcep-session-local-overload {
        description
            "This notification is sent when the local PCEP entity
            enters overload state for a peer.";

        uses notification-instance-hdr;

        uses notification-session-hdr;

        leaf overloaded {
            type boolean;
            description
                 "If the local PCEP entity has informed the peer that
                 it is currently overloaded, then this is set to
                 true. Otherwise, it is set to false.";
        }

        leaf overload-time {
            type uint32;
            units "seconds";
            must "(../overloaded = true or "    +
                "(../overloaded != true  and "  +
                "overload-time = 0))" {
                    error-message
                        "Invalid overload-time";
                    description
                        "This field is only used if overloaded is
                         set to true. Otherwise, it is not used
                         and MUST be set to zero.";
                }
            description
                 "The interval of time that is remaining until the
                 local PCEP entity will cease to be overloaded on
                 this session.";
        }
    } //notification

    notification pcep-session-local-overload-clear {
        description
            "This notification is sent when the local PCEP entity
            leaves overload state for a peer.";

        uses notification-instance-hdr;

        leaf overloaded {
            type boolean;
            description
                 "If the local PCEP entity has informed the peer



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                 that it is currently overloaded, then this is set
                 to true.  Otherwise, it is set to false.";
        }
    } //notification

    notification pcep-session-peer-overload {
        description
            "This notification is sent when a peer enters overload
            state.";

        uses notification-instance-hdr;

        uses notification-session-hdr;

        leaf peer-overloaded {
            type boolean;
            description
                "If the peer has informed the local PCEP entity that
                it is currently overloaded, then this is set to true.
                Otherwise, it is set to false.";
        }

        leaf peer-overload-time {
            type uint32;
            units "seconds";
            must "(../peer-overloaded = true or "    +
                "(../peer-overloaded != true  and "  +
                "peer-overload-time = 0))" {
                    error-message
                        "Invalid peer-overload-time";
                    description
                        "This field is only used if
                         peer-overloaded is set to true.
                         Otherwise, it is not used and MUST
                         be set to zero.";
                }
            description
                "The interval of time that is remaining until the
                peer will cease to be overloaded.  If it is not known
                how long the peer will stay in overloaded state, this
                leaf is set to zero.";
        }
    } //notification

    notification pcep-session-peer-overload-clear {
        description
            "This notification is sent when a peer leaves overload
            state.";



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        uses notification-instance-hdr;

        leaf peer-overloaded {
            type boolean;
            description
                "If the peer has informed the local PCEP entity that
                it is currently overloaded, then this is set to true.
                Otherwise, it is set to false.";
        }
    } //notification
}//module

<CODE ENDS>

8.  Security Considerations

   The YANG module defined in this memo is designed to be accessed via
   the NETCONF protocol [RFC6241].  The lowest NETCONF layer is the
   secure transport layer and the mandatory-to-implement secure
   transport is SSH [RFC6242].  The NETCONF access control model
   [RFC6536] provides the means to restrict access for particular
   NETCONF users to a pre-configured subset of all available NETCONF
   protocol operations and content.

   There are a number of data nodes defined in the YANG module which are
   writable/creatable/deletable (i.e., config true, which is the
   default).  These data nodes may be considered sensitive or vulnerable
   in some network environments.  Write operations (e.g., <edit-config>)
   to these data nodes without proper protection can have a negative
   effect on network operations.

   TBD: List specific Subtrees and data nodes and their sensitivity/
   vulnerability.

9.  Manageability Considerations

9.1.  Control of Function and Policy

9.2.  Information and Data Models

9.3.  Liveness Detection and Monitoring

9.4.  Verify Correct Operations








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9.5.  Requirements On Other Protocols

9.6.  Impact On Network Operations

10.  IANA Considerations

   This document registers a URI in the "IETF XML Registry" [RFC3688].
   Following the format in RFC 3688, the following registration has been
   made.

   URI:  urn:ietf:params:xml:ns:yang:ietf-pcep

   Registrant Contact:  The PCE WG of the IETF.

   XML:  N/A; the requested URI is an XML namespace.

   This document registers a YANG module in the "YANG Module Names"
   registry [RFC6020].

       Name:         ietf-pcep
       Namespace:    urn:ietf:params:xml:ns:yang:ietf-pcep
       Prefix:       pcep
       Reference:    This I-D

11.  Acknowledgements

   The initial document is based on the PCEP MIB [RFC7420].  Further
   this document structure is based on Routing Yang Module
   [I-D.ietf-netmod-routing-cfg].  We would like to thank the authors of
   aforementioned documents.

12.  References

12.1.  Normative References

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

   [RFC3688]  Mealling, M., "The IETF XML Registry", BCP 81, RFC 3688,
              January 2004.

   [RFC5440]  Vasseur, JP. and JL. Le Roux, "Path Computation Element
              (PCE) Communication Protocol (PCEP)", RFC 5440, March
              2009.

   [RFC6020]  Bjorklund, M., "YANG - A Data Modeling Language for the
              Network Configuration Protocol (NETCONF)", RFC 6020,
              October 2010.



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   [RFC6991]  Schoenwaelder, J., "Common YANG Data Types", RFC 6991,
              July 2013.

12.2.  Informative References

   [RFC4655]  Farrel, A., Vasseur, J., and J. Ash, "A Path Computation
              Element (PCE)-Based Architecture", RFC 4655, August 2006.

   [RFC6241]  Enns, R., Bjorklund, M., Schoenwaelder, J., and A.
              Bierman, "Network Configuration Protocol (NETCONF)", RFC
              6241, June 2011.

   [RFC6242]  Wasserman, M., "Using the NETCONF Protocol over Secure
              Shell (SSH)", RFC 6242, June 2011.

   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", RFC 6536, March
              2012.

   [RFC7420]  Koushik, A., Stephan, E., Zhao, Q., King, D., and J.
              Hardwick, "Path Computation Element Communication Protocol
              (PCEP) Management Information Base (MIB) Module", RFC
              7420, December 2014.

   [I-D.ietf-netmod-routing-cfg]
              Lhotka, L., "A YANG Data Model for Routing Management",
              draft-ietf-netmod-routing-cfg-16 (work in progress),
              October 2014.

   [I-D.ietf-netmod-rfc6087bis]
              Bierman, A., "Guidelines for Authors and Reviewers of YANG
              Data Model Documents", draft-ietf-netmod-rfc6087bis-01
              (work in progress), October 2014.


















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Appendix A.  Contributor Addresses

   Young Lee
   Huawei Technologies
   5340 Legacy Drive, Building 3
   Plano, TX 75023, USA

   Phone: (469) 277-5838
   EMail: leeyoung@huawei.com

   Udayasree Palle
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560037
   India

   EMail: udayasree.palle@huawei.com

   Vishnu Pavan Beeram
   Juniper Networks
   USA

   EMail: vbeeram@juniper.net

   Xian Zhang
   Huawei Technologies
   Bantian, Longgang District
   Shenzhen  518129
   P.R.China

   EMail: zhang.xian@huawei.com

Authors' Addresses

   Rohit Pobbathi
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560037
   India

   EMail: rohit.pobbathi@huawei.com










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   Vinod KumarS
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560037
   India

   EMail: vinods.kumar@huawei.com


   Dhruv Dhody (editor)
   Huawei Technologies
   Divyashree Techno Park, Whitefield
   Bangalore, Karnataka  560037
   India

   EMail: dhruv.ietf@gmail.com


   Jonathan Hardwick
   Metaswitch
   100 Church Street
   Enfield  EN2 6BQ
   UK

   EMail: jonathan.hardwick@metaswitch.com


























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