[Docs] [txt|pdf] [Tracker] [WG] [Email] [Diff1] [Diff2] [Nits]

Versions: (draft-jlx-tictoc-1588v2-yang) 00 01 02 03 04 05

Internet Working Group                                   Y. Jiang, Ed.
                                                                X. Liu
Internet-Draft                                                   J. Xu
                                                                Huawei
Intended status: Standards Track                      R. Cummings, Ed.
                                                  National Instruments
Expires: October 2017                                   April 20, 2017


                     YANG Data Model for IEEE 1588v2
                     draft-ietf-tictoc-1588v2-yang-05


Abstract

   This document defines a YANG data model for the configuration of
   IEEE 1588-2008 devices and clocks, and also retrieval of the
   configuration information, data set and running states of IEEE
   1588-2008 clocks.

Status of this Memo

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

   Internet-Drafts are working documents of the Internet Engineering
   Task Force (IETF), its areas, and its working groups.  Note that
   other groups may also distribute working documents as Internet-
   Drafts.

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

   The list of current Internet-Drafts can be accessed at
   http://www.ietf.org/ietf/1id-abstracts.txt

   The list of Internet-Draft Shadow Directories can be accessed at
   http://www.ietf.org/shadow.html

   This Internet-Draft will expire on October 20, 2017.

Copyright Notice

   Copyright (c) 2017 IETF Trust and the persons identified as the
   document authors. All rights reserved.





Jiang, et al          Expires October 20, 2017                [Page 1]


Internet-Draft            1588v2 YANG Model                 April 2017


   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
   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
      1.1. Conventions used in this document ...................... 4
      1.2. Terminology ............................................ 4
   2.   IEEE 1588-2008 YANG Model hierarchy ....................... 5
      2.1. Interpretations from IEEE 1588 Working Group ........... 8
      2.2. Configuration and state ................................ 8
   3.   IEEE 1588-2008 YANG Module ............................... 10
   4.   Security Considerations .................................. 23
   5.   IANA Considerations ...................................... 23
   6.   References ............................................... 23
      6.1. Normative References .................................. 23
      6.2. Informative References ................................ 24
   7.   Acknowledgments .......................................... 25
   Appendix A  Transferring YANG Work to IEEE 1588 WG (Informational)
    .............................................................. 26
      A.1. Assumptions for the Transfer .......................... 26
      A.2. Intellectual Property Considerations .................. 27
      A.3. Namespace and Module Name ............................. 28
      A.4. IEEE 1588 YANG Modules in ASCII Format ................ 29



1. Introduction

   As a synchronization protocol, IEEE 1588-2008 (also known as IEEE
   1588v2) [IEEE1588] is widely supported in the carrier networks,
   industrial networks, automotive networks, and many other
   applications. It can provide high precision time synchronization as
   fine as nano-seconds. The protocol depends on a Precision Time
   Protocol (PTP) engine to decide its own state automatically, and a
   PTP transportation layer to carry the PTP timing and various
   quality messages. The configuration parameters and state data sets
   of IEEE 1588-2008 are numerous.




Jiang, et al          Expires October 20, 2017                [Page 2]


Internet-Draft            1588v2 YANG Model                 April 2017


   According to the concepts described in [RFC3444], IEEE 1588-2008
   itself provides an information model in its normative
   specifications for the data sets (in IEEE 1588-2008 clause 8). Some
   standardization organizations including the IETF have specified
   data models in MIBs (Management Information Bases) for IEEE 1588-
   2008 data sets (e.g. [PTP-MIB], [IEEE8021AS]). These MIBs are
   typically focused on retrieval of state data using the Simple
   Network Management Protocol (SNMP), furthermore, configuration of
   PTP data sets is not considered in [PTP-MIB].

   Some service providers and applications require that the management
   of the IEEE 1588-2008 synchronization network be flexible and more
   Internet-based (typically overlaid on their transport networks).
   Software Defined Network (SDN) is another driving factor, which
   demands an improved configuration capability of synchronization
   networks.

   YANG [RFC6020] is a data modeling language used to model
   configuration and state data manipulated by network management
   protocols like the Network Configuration Protocol (NETCONF)
   [RFC6241]. A small set of built-in data types are defined in
   [RFC6020], and a collection of common data types are further
   defined in [RFC6991]. Advantages of YANG include Internet based
   configuration capability, validation, rollback and so on. All of
   these characteristics make it attractive to become another
   candidate modeling language for IEEE 1588-2008.

   This document defines a YANG [RFC6020] data model for the
   configuration of IEEE 1588-2008 devices and clocks, and retrieval
   of the state data of IEEE 1588-2008 clocks. The data model is based
   on the PTP data sets as specified in [IEEE1588]. The technology
   specific IEEE 1588-2008 information, e.g., those specifically
   implemented by a bridge, a router or a telecom profile, is out of
   scope of this document.

   When used in practice, network products in support of
   synchronization typically conform to one or more IEEE 1588-2008
   profiles.  Each profile specifies how IEEE 1588-2008 is used in a
   given industry (e.g. telecom, automotive) and application.  A
   profile can require features that are optional in IEEE 1588-2008,
   and it can specify new features that use IEEE 1588-2008 as a
   foundation.

   It is expected that the IEEE 1588-2008 YANG module will be used as
   follows:




Jiang, et al          Expires October 20, 2017                [Page 3]


Internet-Draft            1588v2 YANG Model                 April 2017


   o  The IEEE 1588-2008 YANG module can be used as-is for products
   that conform to one of the default profiles specified in IEEE 1588-
   2008.

   o  When the IEEE 1588 standard is revised (e.g. the IEEE 1588
   revision in progress scheduled to be published in 2017), it will
   add some new optional features to its data sets.  The YANG module
   of this document can be revised and extended to add the new
   features (e.g. of IEEE 1588-2017). The YANG "revision" can be used
   to indicate changes to the YANG module.

   o  A profile standard based on IEEE 1588-2008 may create a
   dedicated YANG module for its profile. The profile's YANG module
   may use YANG "import" to import the IEEE 1588-2008 YANG module as
   its foundation.  Then the profile's YANG module can use YANG
   "augment" to add any profile-specific enhancements.

   o  A product that conforms to a profile standard can also create
   its own YANG module. The product's YANG module can "import" the
   profile's module, and then use YANG "augment" to add any product-
   specific enhancements.

1.1. Conventions used in this document

   The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT",
   "SHOULD", "SHOULD NOT", "RECOMMENDED", "MAY", and "OPTIONAL" in
   this document are to be interpreted as described in [RFC2119].

1.2. Terminology

   Most terminologies used in this document are extracted from
   [IEEE1588].

   BC     Boundary Clock

   DS     Data Set

   E2E     End-to-End

   EUI     Extended Unique Identifier.

   GPS     Global Positioning System

   IANA    Internet Assigned Numbers Authority

   IP      Internet Protocol



Jiang, et al          Expires October 20, 2017                [Page 4]


Internet-Draft            1588v2 YANG Model                 April 2017


   NIST    National Institute of Standards and Technology

   NTP     Network Time Protocol

   OC      Ordinary Clock

   P2P     Peer-to-Peer

   PTP     Precision Time Protocol

   TAI     International Atomic Time

   TC      Transparent Clock

   UTC     Coordinated Universal Time

2. IEEE 1588-2008 YANG Model hierarchy

   This section describes the hierarchy of an IEEE 1588-2008 YANG
   module. Query and configuration of device wide or port specific
   configuration information and clock data set is described for this
   version.

   Query and configuration of clock information include:

   - Clock data set attributes in a clock node, including: current-ds,
   parent-ds, default-ds, time-properties-ds, and transparent-clock-
   default-ds.

   - Port-specific data set attributes, including: port-ds and
   transparent-clock-port-ds.

   The readers are assumed to be familiar with IEEE 1588-2008. As all
   PTP terminologies and PTP data set attributes are described in
   details in IEEE 1588-2008 [IEEE1588], this document only outlines
   each of them in the YANG module.

   A simplified graphical representation of the data model is
   typically used by YANG modules as described in [RFC8040]. This
   document uses the same representation and the meaning of the
   symbols in these diagrams is as follows:

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

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



Jiang, et al          Expires October 20, 2017                [Page 5]


Internet-Draft            1588v2 YANG Model                 April 2017


   o  Symbols after data node names: "?" means an optional node, "!"
   means a presence container, and "*" denotes a list and 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.

   o  Arrow ("->") stands for a reference to a particular leaf
   instance in the tree.



   module: ietf-ptp-dataset
       +--rw instance-list* [instance-number]
       |  +--rw instance-number      uint16
       |  +--rw default-ds
       |  |  +--rw two-step-flag?    boolean
       |  |  +--rw clock-identity?   clock-identity-type
       |  |  +--rw number-ports?     uint16
       |  |  +--rw clock-quality
       |  |  |  +--rw clock-class?                  uint8
       |  |  |  +--rw clock-accuracy?               uint8
       |  |  |  +--rw offset-scaled-log-variance?   uint16
       |  |  +--rw priority1?        uint8
       |  |  +--rw priority2?        uint8
       |  |  +--rw domain-number?    uint8
       |  |  +--rw slave-only?       boolean
       |  +--rw current-ds
       |  |  +--rw steps-removed?       uint16
       |  |  +--rw offset-from-master?  time-interval-type
       |  |  +--rw mean-path-delay?     time-interval-type
       |  +--rw parent-ds
       |  |  +--rw parent-port-identity
       |  |  |  +--rw clock-identity?   clock-identity-type
       |  |  |  +--rw port-number?      uint16
       |  |  +--rw parent-stats?        boolean
       |  |  +--rw observed-parent-offset-scaled-log-variance? uint16
       |  |  +--rw observed-parent-clock-phase-change-rate?    int32
       |  |  +--rw grandmaster-identity?                       binary
       |  |  +--rw grandmaster-clock-quality
       |  |  |  +--rw clock-class?                  uint8
       |  |  |  +--rw clock-accuracy?               uint8
       |  |  |  +--rw offset-scaled-log-variance?   uint16
       |  |  +--rw grandmaster-priority1?           uint8
       |  |  +--rw grandmaster-priority2?           uint8


Jiang, et al          Expires October 20, 2017                [Page 6]


Internet-Draft            1588v2 YANG Model                 April 2017


       |  +--rw time-properties-ds
       |  |  +--rw current-utc-offset-valid?   boolean
       |  |  +--rw current-utc-offset?         int16
       |  |  +--rw leap59?                     boolean
       |  |  +--rw leap61?                     boolean
       |  |  +--rw time-traceable?             boolean
       |  |  +--rw frequency-traceable?        boolean
       |  |  +--rw ptp-timescale?              boolean
       |  |  +--rw time-source?                uint8
       |  +--rw port-ds-list* [port-number]
       |     +--rw port-number        -> ../port-identity/port-number
       |     +--rw port-identity
       |     |  +--rw clock-identity?   clock-identity-type
       |     |  +--rw port-number?      uint16
       |     +--rw port-state?          port-state-enumeration
       |     +--rw underlying-interface? if:interface-ref
       |     +--rw log-min-delay-req-interval?    int8
       |     +--rw peer-mean-path-delay?          time-interval-type
       |     +--rw log-announce-interval?         int8
       |     +--rw announce-receipt-timeout?      uint8
       |     +--rw log-sync-interval?             int8
       |     +--rw delay-mechanism?     delay-mechanism-enumeration
       |     +--rw log-min-pdelay-req-interval?   int8
       |     +--rw version-number?                uint8
       +--rw transparent-clock-default-ds
       |  +--rw clock-identity?    clock-identity-type
       |  +--rw number-ports?      uint16
       |  +--rw delay-mechanism?   delay-mechanism-enumeration
       |  +--rw primary-domain?    uint8
       +--rw transparent-clock-port-ds-list* [port-number]
          +--rw port-number           -> ../port-identity/port-number
          +--rw port-identity
          |  +--rw clock-identity?   clock-identity-type
          |  +--rw port-number?      uint16
          +--rw log-min-pdelay-req-interval?   int8
          +--rw faulty-flag?                   boolean
          +--rw peer-mean-path-delay?          time-interval-type











Jiang, et al          Expires October 20, 2017                [Page 7]


Internet-Draft            1588v2 YANG Model                 April 2017


2.1. Interpretations from IEEE 1588 Working Group

   The preceding model and the associated YANG module have some subtle
   differences from the data set specifications of IEEE Std 1588-2008.
   These differences are based on interpretation from the IEEE 1588
   Working Group, and are intended to provide compatibility with
   future revisions of the IEEE 1588 standard.

   In IEEE Std 1588-2008, a physical product can implement multiple
   PTP clocks (i.e. ordinary, boundary, or transparent clock). As
   specified in 1588-2008 subclause 7.1, each of the multiple clocks
   operates in an independent domain. However, the organization of
   multiple PTP domains was not clear in the data sets of IEEE Std
   1588-2008. This document introduces the concept of PTP instance as
   described in the new revision of IEEE 1588. The instance concept is
   used exclusively to allow for optional support of multiple domains.
   The instance number has no usage within PTP messages.

   Based on statements in IEEE 1588-2008 subclauses 8.3.1. and 10.1,
   most transparent clock products have interpreted the transparent
   clock data sets to reside as a singleton at the root level of the
   managed product. Since 1588-2008 transparent clocks are domain
   independent, the instance concept is not applicable for domains.

2.2. Configuration and state

   The information model of IEEE Std 1588-2008 classifies each member
   in PTP data sets as one of the following:

   - Configurable: Writable by management.

   - Dynamic: Read-only to management, and the value is changed by
   1588 protocol operation.

   - Static: Read-only to management, and the value typically does not
   change.

   Under certain circumstances, the classification of an IEEE 1588
   data set member can change. For example, each PTP port's port-state
   is normally Dynamic, i.e., it is read-only to management and only
   IEEE 1588 protocol determines its value. Nevertheless, some IEEE
   1588-2008 products support a proprietary boolean attribute (e.g.,
   leaf in a product-specific 1588 YANG augment) that allows the port-
   state to be configured externally. When the proprietary boolean is
   false, the port-state is Dynamic, representing YANG state data.
   When the proprietary boolean is true, the port-state is
   Configurable, representing YANG configuration data.


Jiang, et al          Expires October 20, 2017                [Page 8]


Internet-Draft            1588v2 YANG Model                 April 2017


   Future revisions of the IEEE 1588 standard are considering formal
   standardization of this sort of proprietary feature, this will be
   reflected in future 1588 YANG module revisions but out scope of
   this document.

   Due to the fact that the classification of 1588 members can change,
   this model uses a single-tree of YANG hierarch rather than
   separates it into a configuration data tree and a state data tree.
   For details on the classification of each PTP data set member,
   refer to the IEEE Std 1588-2008 specification for that member.






































Jiang, et al          Expires October 20, 2017                [Page 9]


Internet-Draft            1588v2 YANG Model                 April 2017


3. IEEE 1588-2008 YANG Module

   <CODE BEGINS> file "ietf-ptp-dataset@2017-04-20.yang"

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

     import ietf-interfaces {
       prefix if;
     }

     organization "IETF TICTOC Working Group";
     contact
         "WG Web:   http://tools.ietf.org/wg/tictoc/
          WG List:  <mailto:tictoc@ietf.org>
          WG Chair: Karen O'Donoghue
                    <mailto:odonoghue@isoc.org>
          WG Chair: Yaakov Stein
                    <mailto: Yaakov_s@rad.com>
          Editor:   Yuanlong Jiang
                    <mailto:jiangyuanlong@huawei.com>
          Editor:   Rodney Cummings
                    <mailto:rodney.cummings@ni.com>";
     description
       "This YANG module defines a data model for the configuration
       of IEEE 1588-2008 clocks, and also for retrieval of the state
       data of IEEE 1588-2008 clocks.";

     revision "2017-04-20" {
       description "Version 5.0";
       reference "draft-ietf-tictoc-1588v2-yang";
     }

     typedef delay-mechanism-enumeration {
       type enumeration {
         enum E2E {
           value 1;
           description
             "The port uses the delay request-response
              mechanism.";
         }
         enum P2P {
           value 2;
           description
             "The port uses the peer delay mechanism.";
         }


Jiang, et al          Expires October 20, 2017               [Page 10]


Internet-Draft            1588v2 YANG Model                 April 2017


         enum DISABLED {
           value 254;
           description
             "The port does not implement any delay
              mechanism.";
         }
       }
       description
         "The propagation delay measuring option used by the
         port. Values for this enumeration are specified
         by the IEEE 1588 standard exclusively.";
       reference
         "IEEE Std 1588-2008: 8.2.5.4.4";
     }

     typedef port-state-enumeration {
       type enumeration {
         enum INITIALIZING {
           value 1;
           description
             "The port is initializing its data sets, hardware, and
             communication facilities.";
         }
         enum FAULTY {
           value 2;
           description
             "The port is in the fault state.";
         }
         enum DISABLED {
           value 3;
           description
             "The port is disabled, and is not communicating PTP
             messages (other than possibly PTP management
             messages).";
         }
         enum LISTENING {
           value 4;
           description
             "The port is listening for an Announce message.";
         }
         enum PRE_MASTER {
           value 5;
           description
             "The port is in the pre-master state.";
         }
         enum MASTER {
           value 6;


Jiang, et al          Expires October 20, 2017               [Page 11]


Internet-Draft            1588v2 YANG Model                 April 2017


           description
             "The port is behaving as a master port.";
         }
         enum PASSIVE {
           value 7;
           description
             "The port is in the passive state.";
         }
         enum UNCALIBRATED {
           value 8;
           description
             "A master port has been selected, but the port is still
             in the uncalibrated state.";
         }
         enum SLAVE {
           value 9;
           description
             "The port is synchronizing to the selected
             master port.";
         }
       }
       description
         "The current state of the protocol engine associated
         with the port.  Values for this enumeration are specified
         by the IEEE 1588 standard exclusively.";
       reference
         "IEEE Std 1588-2008: 8.2.5.3.1, 9.2.5";
     }

     typedef time-interval-type {
       type int64;
       description
         "Derived data type for time interval,
         represented in units of nanoseconds and
         multipled by 2^16";
       reference
         "IEEE Std 1588-2008: 5.3.2";
     }

     typedef clock-identity-type {
       type binary {
         length "8";
       }
       description
         "Derived data type to identify a clock";
       reference
         "IEEE Std 1588-2008: 5.3.4";


Jiang, et al          Expires October 20, 2017               [Page 12]


Internet-Draft            1588v2 YANG Model                 April 2017


     }

     grouping port-identity-grouping {
       description
         "Derived data type to identify a port, which contains
         two members: clockIdentity and portNumber.";
       reference
         "IEEE Std 1588-2008: 5.3.5";

       leaf clock-identity {
         type clock-identity-type;
         description
           "Identity of the clock";
       }

       leaf port-number {
         type uint16;
         description
           "Port number";
       }
     }

     grouping clock-quality-grouping {
       description
         "Derived data type for quality of a clock, which contains
         clockClass, clockAccuracy and offsetScaledLogVariance.";
       reference
         "IEEE Std 1588-2008: 5.3.7";

       leaf clock-class {
         type uint8;
         default 248;
         description
           "The clockClass denotes the traceability of the time
           or frequency distributed by the clock.";
       }

       leaf clock-accuracy {
         type uint8;
         description
           "The clockAccuracy indicates the expected accuracy
            of the clock.";
       }

       leaf offset-scaled-log-variance {
         type uint16;
         description


Jiang, et al          Expires October 20, 2017               [Page 13]


Internet-Draft            1588v2 YANG Model                 April 2017


           "The offsetScaledLogVariance provides an
           estimate of the variations of the clock
           from a linear timescale when it is not synchronized
           to another clock using the protocol.";
       }
     }

     grouping default-ds-entry {
       description
         "Collection of members of the default data set.";

       leaf two-step-flag {
         type boolean;
         description
               "When set, the clock is a two-step clock; otherwise,
               the clock is a one-step clock.";
       }

       leaf clock-identity {
         type clock-identity-type;
         description
           "The clockIdentity of the local clock";
       }

       leaf number-ports {
         type uint16;
         description
           "The number of PTP ports on the device.";
       }

       container clock-quality {
         description
           "The clockQuality of the local clock.";

         uses clock-quality-grouping;
       }

       leaf priority1 {
         type uint8;
         description
           "The priority1 attribute of the local clock.";
       }

       leaf priority2{
         type uint8;
         description
           "The priority2 attribute of the local clock. ";


Jiang, et al          Expires October 20, 2017               [Page 14]


Internet-Draft            1588v2 YANG Model                 April 2017


       }

       leaf domain-number {
         type uint8;
         description
                "The domain number of the current syntonization
               domain.";
       }

       leaf slave-only {
         type boolean;
         description
           "When set, the clock is a slave-only clock.";
       }
     }

     grouping current-ds-entry {
       description
         "Collection of members of current data set.";

       leaf steps-removed {
         type uint16;
         default 0;
         description
           "The number of communication paths traversed
           between the local clock and the grandmaster clock.";
       }
       leaf offset-from-master {
         type time-interval-type;
         description
           "The current value of the time difference between
           a master and a slave clock as computed by the slave.";
       }

       leaf mean-path-delay {
         type time-interval-type;
         description
           "The current value of the mean propagation time between
           a master and a slave clock as computed by the slave.";

       }
     }

     grouping parent-ds-entry {
       description
         "Collection of members of the parent data set.";



Jiang, et al          Expires October 20, 2017               [Page 15]


Internet-Draft            1588v2 YANG Model                 April 2017


       container parent-port-identity {
         description
           "The portIdentity of the port on the master";
         uses port-identity-grouping;
       }
       leaf parent-stats {
         type boolean;
         default false;
         description
           "When set, the values of
            observedParentOffsetScaledLogVariance and
            observedParentClockPhaseChangeRate of parentDS
            have been measured and are valid.";
       }
       leaf observed-parent-offset-scaled-log-variance {
         type uint16;
         default 0xFFFF;
         description
           "An estimate of the parent clock's PTP variance
            as observed by the slave clock.";
       }
       leaf observed-parent-clock-phase-change-rate {
         type int32;
         description
           "An estimate of the parent clock's phase change rate
            as observed by the slave clock.";
       }
       leaf grandmaster-identity {
         type binary{
           length "8";
         }

         description
          "The clockIdentity attribute of the grandmaster clock.";

       }
       container grandmaster-clock-quality {
         description
           "The clockQuality of the grandmaster clock.";
         uses clock-quality-grouping;
       }
       leaf grandmaster-priority1 {
         type uint8;
         description
           "The priority1 attribute of the grandmaster clock.";
       }
       leaf grandmaster-priority2 {


Jiang, et al          Expires October 20, 2017               [Page 16]


Internet-Draft            1588v2 YANG Model                 April 2017


         type uint8;
         description
           "The priority2 attribute of the grandmaster clock.";
       }

     }

     grouping time-properties-ds-entry {
       description
         "Collection of members of the timeProperties data set.";
       leaf current-utc-offset-valid {
         type boolean;
         description
           "When set, the current UTC offset is valid.";
       }
       leaf current-utc-offset {
         type int16;
         description
           "The offset between TAI and UTC when the epoch of the
            PTP system is the PTP epoch, i.e., when ptp-timescale
            is TRUE; otherwise, the value has no meaning.";
       }
       leaf leap59 {
         type boolean;
         description
               "When set, the last minute of the current UTC day
               contains 59 seconds.";
       }
       leaf leap61 {
         type boolean;
         description
               "When set, the last minute of the current UTC day
               contains 61 seconds.";
       }
       leaf time-traceable {
         type boolean;
         description
           "When set, the timescale and the currentUtcOffset are
               traceable to a primary reference.";
       }
       leaf frequency-traceable {
         type boolean;
         description
           "When set, the frequency determining the timescale
            is traceable to a primary reference.";
       }
       leaf ptp-timescale {


Jiang, et al          Expires October 20, 2017               [Page 17]


Internet-Draft            1588v2 YANG Model                 April 2017


         type boolean;
         description
           "When set, the clock timescale of the grandmaster
                clock is PTP; otherwise, the timescale is ARB
               (arbitrary).";
       }
       leaf time-source {
         type uint8;
         description
           "The source of time used by the grandmaster clock.";

       }
     }

     grouping port-ds-entry {
       description
         "Collection of members of the port data set.";

       container port-identity {
         description
           "The portIdentity attribute of the local port.";
         uses port-identity-grouping;
       }

       leaf port-state {
         type port-state-enumeration;
         default "INITIALIZING";
         description
           "Current state associated with the port.";
       }

       leaf underlying-interface {
        type if:interface-ref;
         description
           "Reference to the configured underlying interface that is
           used by this PTP Port (see RFC 7223).";
       }

       leaf log-min-delay-req-interval {
         type int8;
         description
           "The base-two logarithm of the minDelayReqInterval
            (the minimum permitted mean time interval between
            successive Delay_Req messages).";
       }

       leaf peer-mean-path-delay {


Jiang, et al          Expires October 20, 2017               [Page 18]


Internet-Draft            1588v2 YANG Model                 April 2017


         type time-interval-type;
         default 0;
         description
           "An estimate of the current one-way propagation delay
            on the link when the delayMechanism is P2P; otherwise,
            it is zero.";
       }

       leaf log-announce-interval {
         type int8;
         description
           "The base-two logarithm of the mean
            announceInterval (mean time interval between
            successive Announce messages).";
       }

       leaf announce-receipt-timeout {
         type uint8;
         description
           "The number of announceInterval that have to pass
            without receipt of an Announce message before the
            occurrence of the event ANNOUNCE_RECEIPT_TIMEOUT_
            EXPIRES.";
       }

       leaf log-sync-interval {
         type int8;
         description
           "The base-two logarithm of the mean SyncInterval
            for multicast messages.  The rates for unicast
            transmissions are negotiated separately on a per port
            basis and are not constrained by this attribute.";
       }

       leaf delay-mechanism {
         type delay-mechanism-enumeration;
         description
           "The propagation delay measuring option used by the
            port in computing meanPathDelay.";
       }

       leaf log-min-pdelay-req-interval {
         type int8;
         description
           "The base-two logarithm of the
            minPdelayReqInterval (minimum permitted mean time
            interval between successive Pdelay_Req messages).";


Jiang, et al          Expires October 20, 2017               [Page 19]


Internet-Draft            1588v2 YANG Model                 April 2017



       }

       leaf version-number {
         type uint8;
         description
           "The PTP version in use on the port.";
       }
     }

     grouping transparent-clock-default-ds-entry {
       description
         "Collection of members of the transparentClockDefault data
           set (default data set for a transparent clock).";

       leaf clock-identity {
         type clock-identity-type;
         description
           "The clockIdentity of the transparent clock.";
       }
       leaf number-ports {
         type uint16;
         description
           "The number of PTP ports on the device.";
       }
       leaf delay-mechanism {
         type delay-mechanism-enumeration;
         description
           "The propagation delay measuring option
            used by the transparent clock.";
       }
       leaf primary-domain {
         type uint8;
         default 0;
         description
          "The domainNumber of the primary syntonization domain.";

       }
     }

     grouping transparent-clock-port-ds-entry {
       description
         "Collection of members of the transparentClockPort data
          set (port data set for a transparent clock).";

       container port-identity {
         description


Jiang, et al          Expires October 20, 2017               [Page 20]


Internet-Draft            1588v2 YANG Model                 April 2017


           "The portIdentity of the local port.";

         uses port-identity-grouping;
       }
       leaf log-min-pdelay-req-interval {
         type int8;
         description
           "The logarithm to the base 2 of the
            minPdelayReqInterval (minimum permitted mean time
            interval between successive Pdelay_Req messages).";
       }
       leaf faulty-flag {
         type boolean;
         default false;
         description
           "When set, the port is faulty.";
       }
       leaf peer-mean-path-delay {
         type time-interval-type;
         default 0;
         description
           "An estimate of the current one-way propagation delay
            on the link when the delayMechanism is P2P; otherwise,
            it is zero.";
       }
     }

     list instance-list {

       key "instance-number";

       description
         "List of one or more PTP datasets in the device, one for
         each domain (see IEEE 1588-2008 subclause 6.3).
         Each PTP dataset represents a distinct instance of
         PTP implementation in the device (i.e. distinct
         Ordinary Clock or Boundary Clock).";

       leaf instance-number {
         type uint16;
         description
           "The instance number of the current PTP instance";
       }
        container default-ds {
          description
            "The default data set of the clock.";
          uses default-ds-entry;


Jiang, et al          Expires October 20, 2017               [Page 21]


Internet-Draft            1588v2 YANG Model                 April 2017


        }

        container current-ds {
          description
            "The current data set of the clock.";
          uses current-ds-entry;
        }

        container parent-ds {
          description
            "The parent data set of the clock.";
          uses parent-ds-entry;
        }

        container time-properties-ds {
          description
            "The timeProperties data set of the clock.";
          uses time-properties-ds-entry;
        }

        list port-ds-list {
          key "port-number";
          description
            "List of port data sets of the clock.";
          leaf port-number{
            type leafref{
              path "../port-identity/port-number";
            }
            description
              "Refers to the portNumber memer of
              portDS.portIdentity.";
          }
          uses port-ds-entry;
        }
     }

     container transparent-clock-default-ds {
       description
         "The members of the transparentClockDefault Data Set";
       uses transparent-clock-default-ds-entry;
     }

     list transparent-clock-port-ds-list {
       key "port-number";
       description
         "List of transparentClockPort data sets
          of the transparent clock.";


Jiang, et al          Expires October 20, 2017               [Page 22]


Internet-Draft            1588v2 YANG Model                 April 2017


       leaf port-number {
         type leafref {
           path "../port-identity/port-number";
         }
          description
            "Refers to the portNumber memer
             of transparentClockPortDS.portIdentity.";
        }
        uses transparent-clock-port-ds-entry;
      }
   }

   <CODE ENDS>

4. Security Considerations

   YANG modules are designed to be accessed via the NETCONF protocol
   [RFC6241], thus security considerations in [RFC6241] apply here.
   Security measures such as using the NETCONF over SSH [RFC6242] and
   restricting its use with access control [RFC6536] can further
   improve its security, avoid injection attacks and misuse of the
   protocol.

   Some data nodes defined in this YANG module are writable, and any
   changes to them may adversely impact a synchronization network.

5. IANA Considerations

   This document registers a URI in the IETF XML registry, and the
   following registration is requested to be made:
   URI: urn:ietf:params:xml:ns:yang:ietf-ptp-dataset

   This document registers a YANG module in the YANG Module Names:
   name: ietf-ptp-dataset namespace: urn:ietf:params:xml:ns:yang:ietf-
   ptp-dataset


6. References

6.1.  Normative References

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

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


Jiang, et al          Expires October 20, 2017               [Page 23]


Internet-Draft            1588v2 YANG Model                 April 2017


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

   [RFC7223] Bjorklund, M., "A YANG Data Model for Interface
             Management", RFC 7223, May 2014

   [IEEE1588] IEEE, "IEEE Standard for a Precision Clock
             Synchronization Protocol for Networked Measurement and
             Control Systems", IEEE Std 1588-2008, July 2008

6.2. Informative References

   [IEEE8021AS] IEEE, "Timing and Synchronizations for Time-Sensitive
             Applications in Bridged Local Area Networks", IEEE
             802.1AS-2001, 2011

   [PTP-MIB] Shankarkumar, V., Montini, L., Frost, T., and Dowd, G.,
             "Precision Time Protocol Version 2 (PTPv2) Management
             Information Base", draft-ietf-tictoc-ptp-mib-12, Work in
             progress

   [RFC8040] Bierman, A., Bjorklund, M., and Watsen, K., "RESTCONF
             protocol", RFC 8040, January 2017

   [RFC3444] Pras, A. and J. Schoenwaelder, "On the Difference between
             Information Models and Data Models", RFC 3444, January
             2003

   [RFC4663] Harrington, D., "Transferring MIB Work from IETF Bridge
             MIB WG to IEEE 802.1 WG", RFC 4663, September 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







Jiang, et al          Expires October 20, 2017               [Page 24]


Internet-Draft            1588v2 YANG Model                 April 2017


7. Acknowledgments

   The authors would like to thank Joe Gwinn, Mahesh Jethanandani, Tal
   Mizrahi, Opher Ronen and Liang Geng for their valuable reviews and
   suggestions, and thank Benoit Claise and Radek Krejci for their
   validation of the YANG module.










































Jiang, et al          Expires October 20, 2017               [Page 25]


Internet-Draft            1588v2 YANG Model                 April 2017


Appendix A  Transferring YANG Work to IEEE 1588 WG (Informational)

   This appendix describes a future plan to transition responsibility
   for IEEE 1588 YANG modules from the IETF TICTOC Working Group (WG)
   to the IEEE 1588 WG, which develops the time synchronization
   technology that the YANG modules are designed to manage.

   This appendix is forward-looking with regard to future
   standardization roadmaps in IETF and IEEE.  Since those roadmaps
   cannot be predicted with significant accuracy, this appendix is
   informational, and it does not specify imperatives or normative
   specifications of any kind.

   The IEEE 1588-2008 YANG module of this standard represents a
   cooperation between IETF (for YANG) and IEEE (for 1588).  For the
   initial standardization of IEEE-1588 YANG modules, the information
   model is relatively clear (i.e. IEEE 1588 data sets), but expertise
   in YANG is required, making IETF an appropriate location for the
   standards.  The TICTOC WG has expertise with IEEE 1588, making it
   the appropriate location within IETF.

   The IEEE 1588 WG anticipates future changes to its standard on an
   ongoing basis.  As IEEE 1588 WG members gain practical expertise
   with YANG, the IEEE 1588 WG will become more appropriate for
   standardization of its YANG modules.  As the IEEE 1588 standard is
   revised and/or amended, IEEE 1588 members can more effectively
   synchronize the revision of this YANG module with future versions
   of the IEEE 1588 standard.

   This appendix is meant to establish some clear expectations between
   IETF and IEEE about the future transfer of IEEE 1588 YANG modules
   to the IEEE 1588 WG.  The goal is to assist in making the future
   transfer as smooth as possible. As the transfer takes place, some
   case-by-case situations are likely to arise, which can be handled
   by discussion on the IETF TICTOC WG mailing lists and/or
   appropriate liaisons.

   This appendix obtained insight from [RFC4663], an informational
   memo that described a similar transfer of MIB work from the IETF
   Bridge MIB WG to the IEEE 802.1 WG.


A.1. Assumptions for the Transfer

   For the purposes of discussion in this appendix, assume that the
   IETF TICTOC WG has approved a standard YANG module for a published
   IEEE 1588 standard.  As of this writing, this is IEEE Std 1588-2008,


Jiang, et al          Expires October 20, 2017               [Page 26]


Internet-Draft            1588v2 YANG Model                 April 2017


   but it is possible that YANG for subsequent 1588 revisions could be
   published from the IETF TICTOC WG.  For discussion in this appendix,
   we use the phrase "last IETF 1588 YANG" to refer to most recently
   published 1588 YANG from the IETF TICTOC WG.

   The IEEE-SA Standards Board New Standards Committee (NesCom)
   handles new Project Authorization Requests (PARs) (see
   http://standards.ieee.org/board/nes/). PARs are roughly the
   equivalent of IETF Working Group Charters and include information
   concerning the scope, purpose, and justification for
   standardization projects.

   Assume that IEEE 1588 has an approved PAR that explicitly specifies
   development of a YANG module. The transfer of YANG work will occur
   in the context of this IEEE 1588 PAR. For discussion in this
   appendix, we use the phrase "first IEEE 1588 YANG" to refer to the
   first IEEE 1588 standard for YANG.

   Assume that as part of the transfer of YANG work, the IETF TICTOC
   WG agrees to cease all work on standard YANG modules for IEEE 1588.

   Assume that the IEEE 1588 WG has participated in the development of
   the last IETF 1588 YANG module, such that the first IEEE 1588 YANG
   module will effectively be a revision of it. In other words, the
   transfer of YANG work will be relatively clean.

   The actual conditions for the future transfer can be such that the
   preceding assumptions do not hold. Exceptions to the assumptions
   will need to be addressed on a case-by-case basis at the time of
   the transfer. This appendix describes topics that can be addressed
   based on the preceding assumptions.

A.2. Intellectual Property Considerations

   During review of the legal issues associated with transferring
   Bridge MIB WG documents to the IEEE 802.1 WG (Section 3.1 and
   Section 9 of [RFC4663]), it was concluded that the IETF does not
   have sufficient legal authority to make the transfer to IEEE
   without the consent of the document authors.



   If the last IETF 1588 YANG is published as a RFC, the work is
   required to be transferred from the IETF to the IEEE, so that IEEE
   1588 WG can begin working on the first IEEE 1588 YANG.




Jiang, et al          Expires October 20, 2017               [Page 27]


Internet-Draft            1588v2 YANG Model                 April 2017


   When work on the first IEEE YANG module begins in the IEEE 1588 WG,
   that work derives from the last IETF YANG module of this RFC,
   requiring a transfer of that work from the IETF to the IEEE. In
   order to avoid having the transfer of that work be dependent on the
   availability of this RFC's authors at the time of its publication,
   the IEEE Standards Association department of Risk Management and
   Licensing provided the appropriate forms and mechanisms for this
   document's authors to assign a non-exclusive license for IEEE to
   create derivative works from this document. Those IEEE forms and
   mechanisms will be updated as needed during the development of this
   document and any future IETF YANG modules for IEEE 1588. This will
   help to make the future transfer of work from IETF to IEEE occur as
   smoothly as possible.

   As stated in the initial "Status of this Memo", the YANG module in
   this document conforms to the provisions of BCP 78. The IETF will
   retain all the rights granted at the time of publication in the
   published RFCs.

A.3. Namespace and Module Name

   As specified in the "IANA Considerations" section, the YANG module
   in this document uses IETF as the root of its URN namespace and
   YANG module name.

   Use of IETF as the root of these names implies that the YANG module
   is standardized in a Working Group of IETF, using the IETF
   processes. If the IEEE 1588 Working Group were to continue using
   these names rooted in IETF, the IEEE 1588 YANG standardization
   would need to continue in the IETF. The goal of transferring the
   YANG work is to avoid this sort of dependency between standards
   organizations.

   IEEE 802 has an active PAR (IEEE P802d) for creating a URN
   namespace for IEEE use (see
   http://standards.ieee.org/develop/project/802d.html). It is likely
   that this IEEE 802 PAR will be approved and published prior to the
   transfer of YANG work to the IEEE 1588 WG. If so, the IEEE 1588 WG
   can use the IEEE URN namespace for the first IEEE 1588 YANG module,
   such as:

      urn:ieee:Std:1588:yang:ieee1588-ptp-dataset

   where "ieee1588-ptp-dataset" is the registered YANG module name in
   the IEEE.




Jiang, et al          Expires October 20, 2017               [Page 28]


Internet-Draft            1588v2 YANG Model                 April 2017


   Under the assumptions of section A.1, the first IEEE 1588 YANG
   module prefix can be the same as the last IETF 1588 YANG module
   prefix (i.e. "ptp-dataset"), since the nodes within both YANG
   modules are compatible.

   The result of these name changes are that for complete
   compatibility, a server (i.e. IEEE 1588 node) can choose to
   implement a YANG module for the last IETF 1588 YANG module (with
   IETF root) as well as the first IEEE 1588 YANG module (with IEEE
   root).  Since the content of the YANG module transferred are the
   same, the server implementation is effectively common for both.

   From a client's perspective, a client of the last IETF 1588 YANG
   module (or earlier) looks for the IETF-rooted module name; and a
   client of the first IEEE 1588 YANG module (or later) looks for the
   IEEE-rooted module name.

A.4. IEEE 1588 YANG Modules in ASCII Format

   Although IEEE 1588 can certainly decide to publish YANG modules
   only in the PDF format that they use for their standard documents,
   without publishing an ASCII version, most network management
   systems cannot import the YANG module directly from the PDF. Thus,
   not publishing an ASCII version of the YANG module would negatively
   impact implementers and deployers of YANG modules and would make
   potential IETF reviews of YANG modules more difficult.

   This appendix recommends that the IEEE 1588 WG consider future
   plans for:

   o Public availability of the ASCII YANG modules during project
      development. These ASCII files allow IETF participants to access
      these documents for pre-standard review purposes.

   o Public availability of the YANG portion of published IEEE 1588
      standards, provided as an ASCII file for each YANG module.
      These ASCII files are intended for use of the published IEEE
      1588 standard.

   As an example of public availability during project development,
   IEEE 802 uses the same repository that IETF uses for YANG module
   development (see https://github.com/YangModels/yang). IEEE branches
   are provided for experimental work (i.e. pre-PAR) as well as
   standard work (post-PAR drafts). IEEE-SA has approved use of this
   repository for project development, but not for published standards.




Jiang, et al          Expires October 20, 2017               [Page 29]


Internet-Draft            1588v2 YANG Model                 April 2017


   As an example of public availability of YANG modules for published
   standards, IEEE 802.1 provides a public list of ASCII files for MIB
   (see http://www.ieee802.org/1/files/public/MIBs/ and
   http://www.ieee802.org/1/pages/MIBS.html), and analogous lists are
   planned for IEEE 802.1 YANG files.











































Jiang, et al          Expires October 20, 2017               [Page 30]


Internet-Draft            1588v2 YANG Model                 April 2017


Authors' Addresses


   Yuanlong Jiang (Editor)
   Huawei Technologies Co., Ltd.
   Bantian, Longgang district
   Shenzhen 518129, China
   Email: jiangyuanlong@huawei.com


   Xian Liu
   Huawei Technologies Co., Ltd.
   Bantian, Longgang district
   Shenzhen 518129, China
   lene.liuxian@huawei.com


   Jinchun Xu
   Huawei Technologies Co., Ltd.
   Bantian, Longgang district
   Shenzhen 518129, China
   xujinchun@huawei.com

   Rodney Cummings (Editor)
   National Instruments
   11500 N. Mopac Expwy
   Bldg. C
   Austin, TX 78759-3504
   Email: Rodney.Cummings@ni.com



















Jiang, et al          Expires October 20, 2017               [Page 31]


Html markup produced by rfcmarkup 1.121, available from https://tools.ietf.org/tools/rfcmarkup/