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Versions: (draft-somaraju-core-sid) 00 01 02 03 04

Internet Engineering Task Force                        M. Veillette, Ed.
Internet-Draft                                   Trilliant Networks Inc.
Intended status: Standards Track                           A. Pelov, Ed.
Expires: December 6, 2018                                         Acklio
                                                           June 04, 2018


                   YANG Schema Item iDentifier (SID)
                         draft-ietf-core-sid-04

Abstract

   YANG Schema Item iDentifiers (SID) are globally unique 64-bit
   unsigned numbers used to identify YANG items.  This document defines
   the semantics, the registration, and assignment processes of SIDs.
   To enable the implementation of these processes, this document also
   defines a file format used to persist and publish assigned SIDs.

Status of This Memo

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

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

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

   This Internet-Draft will expire on December 6, 2018.

Copyright Notice

   Copyright (c) 2018 IETF Trust and the persons identified as the
   document authors.  All rights reserved.

   This document is subject to BCP 78 and the IETF Trust's Legal
   Provisions Relating to IETF Documents
   (https://trustee.ietf.org/license-info) in effect on the date of
   publication of this document.  Please review these documents
   carefully, as they describe your rights and restrictions with respect
   to this document.  Code Components extracted from this document must
   include Simplified BSD License text as described in Section 4.e of




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   the Trust Legal Provisions and are provided without warranty as
   described in the Simplified BSD License.

Table of Contents

   1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . .   2
   2.  Terminology and Notation  . . . . . . . . . . . . . . . . . .   3
   3.  ".sid" file lifecycle . . . . . . . . . . . . . . . . . . . .   4
   4.  ".sid" file format  . . . . . . . . . . . . . . . . . . . . .   7
   5.  Security Considerations . . . . . . . . . . . . . . . . . . .  11
   6.  IANA Considerations . . . . . . . . . . . . . . . . . . . . .  11
     6.1.  "SID mega-range" registry . . . . . . . . . . . . . . . .  11
       6.1.1.  IANA SID Mega-Range Registry  . . . . . . . . . . . .  12
       6.1.2.  IANA "RFC SID range assignment" sub-registries  . . .  13
     6.2.  "YANG module assignment" registry . . . . . . . . . . . .  14
   7.  Acknowledgments . . . . . . . . . . . . . . . . . . . . . . .  14
   8.  References  . . . . . . . . . . . . . . . . . . . . . . . . .  14
     8.1.  Normative References  . . . . . . . . . . . . . . . . . .  14
     8.2.  Informative References  . . . . . . . . . . . . . . . . .  15
   Appendix A.  ".sid" file example  . . . . . . . . . . . . . . . .  16
   Authors' Addresses  . . . . . . . . . . . . . . . . . . . . . . .  25

1.  Introduction

   Some of the items defined in YANG [RFC7950] require the use of a
   unique identifier.  In both NETCONF [RFC6241] and RESTCONF [RFC8040],
   these identifiers are implemented using names.  To allow the
   implementation of data models defined in YANG in constrained devices
   and constrained networks, a more compact method to identify YANG
   items is required.  This compact identifier, called SID, is encoded
   using a 64-bit unsigned integer.  The following items are identified
   using SIDs:

   o  identities

   o  data nodes (Note: including those part of a YANG template as
      defined by the 'yang-data' extension.)

   o  RPCs and associated input(s) and output(s)

   o  actions and associated input(s) and output(s)

   o  notifications and associated information

   o  YANG modules, submodules and features

   To minimize their size, SIDs are often represented as a difference
   between the current SID and a reference SID.  Such difference is



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   called "delta", shorthand for "delta-encoded SID".  Conversion from
   SIDs to deltas and back to SIDs is a stateless process.  Each
   protocol implementing deltas must unambiguously define the reference
   SID for each YANG item.

   SIDs are globally unique numbers, a registration system is used in
   order to guarantee their uniqueness.  SIDs are registered in blocks
   called "SID ranges".

   Assignment of SIDs to YANG items can be automated, the recommended
   process to assign SIDs is as follows:

   1.  A tool extracts the different items defined for a specific YANG
       module.

   2.  The list of items is sorted in alphabetical order, 'namespace' in
       descending order, 'identifier' in ascending order.  The
       'namespace' and 'identifier' formats are described in the YANG
       module 'ietf-sid-file' defined in Section 4.

   3.  SIDs are assigned sequentially from the entry point up to the
       size of the registered SID range.  This approach is recommended
       to minimize the serialization overhead, especially when delta
       encoding is implemented.

   4.  If the number of items exceeds the SID range(s) allocated to a
       YANG module, an extra range is added for subsequent assignments.

   SIDs are assigned permanently, items introduced by a new revision of
   a YANG module are added to the list of SIDs already assigned.  This
   process can also be automated using the same method described above,
   only unassigned YANG items are processed at step #3.

   Section 3 provides more details about the registration process of
   YANG modules and associated SIDs.  To enable the implementation of
   this registry, Section 4 defines a standard file format used to store
   and publish SIDs.

2.  Terminology and Notation

   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].

   The following terms are defined in [RFC7950]:

   o  action




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   o  feature

   o  module

   o  notification

   o  RPC

   o  schema node

   o  schema tree

   o  submodule

   The following term is defined in [RFC8040]:

   o  yang-data extension

   This specification also makes use of the following terminology:

   o  delta : Difference between the current SID and a reference SID.  A
      reference SID is defined for each context for which deltas are
      used.

   o  item: A schema node, an identity, a module, a submodule or a
      feature defined using the YANG modeling language.

   o  path: A path is a string that identifies a schema node within the
      schema tree.  A path consists of the list of schema node
      identifier(s) separated by slashes ("/").  Schema node
      identifier(s) are always listed from the top-level schema node up
      to the targeted schema node. (e.g. "/ietf-system:system-
      state/clock/current-datetime")

   o  YANG Schema Item iDentifier (SID): Unsigned integer used to
      identify different YANG items.

3.  ".sid" file lifecycle

   YANG is a language designed to model data accessed using one of the
   compatible protocols (e.g.  NETCONF [RFC6241], RESCONF [RFC8040] and
   CoMI [I-D.ietf-core-comi]).  A YANG module defines hierarchies of
   data, including configuration, state data, RPCs, actions and
   notifications.

   YANG modules are not necessary created in the context of constrained
   applications.  YANG modules can be implemented using NETCONF
   [RFC6241] or RESTCONF [RFC8040] without the need to assign SIDs.



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   As needed, authors of YANG modules can assign SIDs to their YANG
   modules.  This process starts by the registration of a SID range.
   Once a SID range is registered, the owner of this range assigns sub-
   ranges to each YANG module in order to generate the associated ".sid"
   files.  Generation of ".sid" files SHOULD be performed using an
   automated tool.

   Registration of the .sid file associated to a YANG module is optional
   but recommended to promote interoperability between devices and to
   avoid duplicate allocation of SIDs to a single YANG module.

   The following activity diagram summarizes the creation of a YANG
   module and its associated .sid file.






































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          +---------------+
     O    | Creation of a |
    -|- ->| YANG module   |
    / \   +---------------+
                  |
                  V
           /-------------\
          / Standardized  \ yes
          \ YANG module ? /-------------+
           \-------------/              |
                  | no                  |
                  V                     V
           /-------------\      +---------------+
          / Constrained   \ yes | SID range     |
      +-->\ application ? /---->| registration  |
      |    \-------------/      +---------------+
      |           | no                  |
      |           V                     V
      |   +---------------+     +---------------+
      +---| YANG module   |     | SID sub-range |
          | update        |     | assignment    |
          +---------------+     +---------------+
                                        |
                                        V
                                +---------------+
                                | .sid file     |
                                | generation    |
                                +---------------+
                                        |
                                        V
                                 /-------------\      +---------------+
                                /  Publicly     \ yes | YANG module   |
                                \  available ?  /---->| registration  |
                                 \-------------/      +---------------+
                                        | no                  |
                                        +---------------------+
                                        |
                                      [DONE]

   Each time a YANG module or one of its imported module(s) or included
   sub-module(s) is updated, the ".sid" file MAY need to be updated.
   This update SHOULD also be performed using an automated tool.

   If a new revision requires more SIDs than initially allocated, a new
   SID range MUST be added to the 'assignment-ranges'.  These extra SIDs
   are used for subsequent assignements.





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   The following activity diagram summarizes the update of a YANG module
   and its associated .sid file.

          +---------------+
     O    | Update of the |
    -|- ->| YANG module   |
    / \   | or include(s) |
          | or import(s)  |
          +---------------+
                  |
                  V
              /-------------\
             /  New items    \ yes
             \  created  ?   /------+
              \-------------/       |
                     | no           V
                     |       /-------------\      +----------------+
                     |      /  SID range    \ yes | Extra sub-range|
                     |      \  exhausted ?  /---->| assignment     |
                     |       \-------------/      +----------------+
                     |              | no                  |
                     |              +---------------------+
                     |              |
                     |              V
                     |      +---------------+
                     |      | .sid file     |
                     |      | update based  |
                     |      | on previous   |
                     |      | .sid file     |
                     |      +---------------+
                     |              |
                     |              V
                     |       /-------------\      +---------------+
                     |      /  Publicly     \ yes | YANG module   |
                     |      \  available ?  /---->| registration  |
                     |       \-------------/      +---------------+
                     |              | no                  |
                     +--------------+---------------------+
                                    |
                                  [DONE]


4.  ".sid" file format

   ".sid" files are used to persist and publish SIDs assigned to the
   different YANG items of a specific YANG module.  The following YANG
   module defined the structure of this file, encoding is performed
   using the rules defined in [RFC7951].



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   <CODE BEGINS> file "ietf-sid-file@2017-11-26.yang"
   module ietf-sid-file {
     namespace "urn:ietf:params:xml:ns:yang:ietf-sid-file";
     prefix sid;

     import ietf-yang-types {
       prefix yang;
     }

     import ietf-comi {
       prefix comi;
     }

     organization
       "IETF Core Working Group";

     contact
       "Michel Veillette
        <mailto:michel.veillette@trilliant.com>

        Andy Bierman
        <mailto:andy@yumaworks.com>

        Alexander Pelov
        <mailto:a@ackl.io>";

     description
       "This module defines the structure of the .sid files.

        Each .sid file contains the mapping between the different
        string identifiers defined by a YANG module and a
        corresponding numeric value called SID.";

     revision 2017-11-26 {
       description
         "Initial revision.";
       reference
         "[I-D.ietf-core-sid] YANG Schema Item iDentifier (SID)";
     }

     typedef revision-identifier {
       type string {
         pattern '\d{4}-\d{2}-\d{2}';
       }
       description
         "Represents a date in YYYY-MM-DD format.";
     }




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     typedef schema-node-path {
       type string {
         pattern
           '/[a-zA-Z_][a-zA-Z0-9\-_.]*:[a-zA-Z_][a-zA-Z0-9\-_.]*' +
           '(/[a-zA-Z_][a-zA-Z0-9\-_.]*(:[a-zA-Z_][a-zA-Z0-9\-_.]*)?)*';
       }
       description
         "Identifies a schema-node path string for use in the
          SID registry. This string format follows the rules
          for an instance-identifier, as defined in RFC 7959,
          except that no predicates are allowed.

          This format is intended to support the YANG 1.1 ABNF
          for a schema node identifier, except module names
          are used instead of prefixes, as specified in RFC 7951.";
       reference
         "RFC 7950, The YANG 1.1 Data Modeling Language;
          Section 6.5: Schema Node Identifier;
          RFC 7951, JSON Encoding of YANG Data;
          Section 6.11: The instance-identifier type";
     }

     leaf module-name {
       type yang:yang-identifier;
       description
         "Name of the YANG module associated with this .sid file.";
     }

     leaf module-revision {
       type revision-identifier;
       description
         "Revision of the YANG module associated with this .sid file.
          This leaf is not present if no revision statement is
          defined in the YANG module.";
     }

     list assigment-ranges {
       key "entry-point";
       description
         "SID range(s) allocated to the YANG module identified by
          'module-name' and 'module-revision'.";

       leaf entry-point {
         type comi:sid;
         mandatory true;
         description
           "Lowest SID available for assignment.";
       }



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       leaf size {
         type uint64;
         mandatory true;
         description
           "Number of SIDs available for assignment.";
       }
     }

     list items {
       key "namespace identifier";
       description
         "Each entry within this list defined the mapping between
          a YANG item string identifier and a SID. This list MUST
          include a mapping entry for each YANG item defined by
          the YANG module identified by 'module-name' and
          'module-revision'.";

       leaf namespace {
         type enumeration {
           enum module {
             value 0;
             description
               "All module and submodule names share the same
                global module identifier namespace.";
           }
           enum identity {
             value 1;
             description
               "All identity names defined in a module and its
                submodules share the same identity identifier
                namespace.";
           }
           enum feature {
             value 2;
             description
               "All feature names defined in a module and its
                submodules share the same feature identifier
                namespace.";
           }
           enum data {
             value 3;
             description
               "The namespace for all data nodes, as defined in YANG.";
           }
         }
         description
           "Namespace of the YANG item for this mapping entry.";
       }



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       leaf identifier {
         type union {
           type yang:yang-identifier;
           type schema-node-path;
         }
         description
           "String identifier of the YANG item for this mapping entry.

            If the corresponding 'namespace' field is 'module',
            'feature', or 'identity', then this field MUST
            contain a valid YANG identifier string.

            If the corresponding 'namespace' field is 'data',
            then this field MUST contain a valid schema node
            path.";
        }

       leaf sid {
         type comi:sid;
         mandatory true;
         description
           "SID assigned to the YANG item for this mapping entry.";
       }
     }
   }
   <CODE ENDS>

5.  Security Considerations

   The security considerations of [RFC7049] and [RFC7950] apply.

   This document defines a new type of identifier used to encode data
   models defined in YANG [RFC7950].  As such, this identifier does not
   contribute to any new security issues in addition of those identified
   for the specific protocols or contexts for which it is used.

6.  IANA Considerations

6.1.  "SID mega-range" registry

   The name of this registry is "SID mega-range".  This registry is used
   to delegate the management of block of SIDs for third party's (e.g.
   SDO, registrar).

   Each entry in this registry must include:

   o  The entry point (first entry) of the registered SID range.




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   o  The size of the registered SID range.

   o  The contact information of the requesting organization including:

      *  Organization name

      *  Primary contact name, email address, and phone number

      *  Secondary contact name, email address, and phone number

   The initial entry in this registry is allocated to IANA:

   +-------------+---------+-------------------+
   | Entry Point | Size    | Organization name |
   +-------------+---------+-------------------+
   | 0           | 1000000 | IANA              |
   +-------------+---------+-------------------+

   The IANA policies for future additions to this registry are
   "Hierarchical Allocation, Expert Review" [RFC5226].  Prior to a first
   allocation, the requesting organization must demonstrate a functional
   registry infrastructure.  On subsequent allocation request(s), the
   organization must demonstrate the exhaustion of the prior range.
   These conditions need to be asserted by the assigned expert(s).

6.1.1.  IANA SID Mega-Range Registry

   The first million SIDs assigned to IANA is sub-divided as follow:

   o  The range of 0 to 999 is reserved for future extensions.  The IANA
      policy for this range is "IETF review" [RFC5226].

   o  The range of 1000 to 59,999 is reserved for YANG modules defined
      in RFCs.  The IANA policy for future additions to this sub-
      registry is "RFC required" [RFC5226].  Allocation within this
      range requires publishing of the associated ".yang" and ".sid"
      files in the YANG module registry.  The allocation within this
      range is done prior to the RFC publication but should not be done
      prior to the working group adoption.

   o  The range of 60,000 to 99,999 is reserved for experimental YANG
      modules.  This range MUST NOT be used in operational deployments
      since these SIDs are not globally unique which limit their
      interoperability.  The IANA policy for this range is "Experimental
      use" [RFC5226].

   o  The range of 100,000 to 999,999 is reserved for standardized YANG
      modules.  The IANA policy for future additions to this sub-



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      registry is "Specification Required" [RFC5226].  Allocation within
      this range requires publishing of the associated ".yang" and
      ".sid" files in the YANG module registry.

   +-------------+---------------+------------------------+
   | Entry Point | Size          | IANA policy            |
   +-------------+---------------+------------------------+
   | 0           | 1,000         | IETF review            |
   | 1,000       | 59,000        | RFC required           |
   | 60,000      | 40,000        | Experimental use       |
   | 100,000     | 1,000,000,000 | Specification Required |
   +-------------+---------------+------------------------+

   The size of a SID range assigned to a YANG module should be at least
   33% above the current number of YANG items.  This headroom allows
   assignment within the same range of new YANG items introduced by
   subsequent revisions.  A larger SID range size may be requested by
   the authors if this recommendation is considered insufficient.  It is
   important to note that an extra SID range can be allocated to an
   existing YANG module if the initial range is exhausted.

6.1.2.  IANA "RFC SID range assignment" sub-registries

   The name of this sub-registry is "RFC SID range assignment".  This
   sub-registry corresponds to the SID entry point 1000, size 59000.
   Each entry in this sub-registry must include the SID range entry
   point, the SID range size, the YANG module name, the RFC number.

   Initial entries in this registry are as follows:

   +-------------+------+------------------+----------------------+
   | Entry Point | Size | Module name      | RFC number           |
   +-------------+------+------------------+----------------------+
   | 1000        | 100  | ietf-comi        | [I-D.ietf-core-comi] |
   | 1100        | 50   | ietf-yang-types  | [RFC6021]            |
   | 1150        | 50   | ietf-inet-types  | [RFC6021]            |
   | 1200        | 50   | iana-crypt-hash  | [RFC7317]            |
   | 1250        | 50   | ietf-netconf-acm | [RFC6536]            |
   | 1300        | 50   | ietf-sid-file    | RFCXXXX              |
   | 1500        | 100  | ietf-interfaces  | [RFC7223]            |
   | 1600        | 100  | ietf-ip          | [RFC7277]            |
   | 1700        | 100  | ietf-system      | [RFC7317]            |
   | 1800        | 400  | iana-if-type     | [RFC7224]            |
   +-------------+------+------------------+----------------------+

   // RFC Ed.: replace XXXX with RFC number assigned to this draft.





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6.2.  "YANG module assignment" registry

   The name of this registry is "YANG module assignment".  This registry
   is used to track which YANG modules have been assigned and the
   specific YANG items assignment.  Each entry in this sub-registry must
   include:

   o  The YANG module name

   o  The associated ".yang" file(s)

   o  The associated ".sid" file

   The validity of the ".yang" and ".sid" files added to this registry
   MUST be verified.

   o  The syntax of the registered ".yang" and ".sid" files must be
      valid.

   o  Each YANG item defined by the registered ".yang" file must have a
      corresponding SID assigned in the ".sid" file.

   o  Each SID is assigned to a single YANG item, duplicate assignment
      is not allowed.

   o  The SID range(s) defined in the ".sid" file must be unique, must
      not conflict with any other SID ranges defined in already
      registered ".sid" files.

   o  The ownership of the SID range(s) should be verify.

   The IANA policy for future additions to this registry is "First Come
   First Served" as described in [RFC5226].

7.  Acknowledgments

   The authors would like to thank Andy Bierman, Carsten Bormann,
   Abhinav Somaraju, Laurent Toutain and Randy Turner for their help
   during the development of this document and their useful comments
   during the review process.

8.  References

8.1.  Normative References







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

   [RFC7049]  Bormann, C. and P. Hoffman, "Concise Binary Object
              Representation (CBOR)", RFC 7049, DOI 10.17487/RFC7049,
              October 2013, <https://www.rfc-editor.org/info/rfc7049>.

   [RFC7950]  Bjorklund, M., Ed., "The YANG 1.1 Data Modeling Language",
              RFC 7950, DOI 10.17487/RFC7950, August 2016,
              <https://www.rfc-editor.org/info/rfc7950>.

   [RFC7951]  Lhotka, L., "JSON Encoding of Data Modeled with YANG",
              RFC 7951, DOI 10.17487/RFC7951, August 2016,
              <https://www.rfc-editor.org/info/rfc7951>.

8.2.  Informative References

   [I-D.ietf-core-comi]
              Veillette, M., Stok, P., Pelov, A., and A. Bierman, "CoAP
              Management Interface", draft-ietf-core-comi-02 (work in
              progress), December 2017.

   [RFC5226]  Narten, T. and H. Alvestrand, "Guidelines for Writing an
              IANA Considerations Section in RFCs", RFC 5226,
              DOI 10.17487/RFC5226, May 2008,
              <https://www.rfc-editor.org/info/rfc5226>.

   [RFC6021]  Schoenwaelder, J., Ed., "Common YANG Data Types",
              RFC 6021, DOI 10.17487/RFC6021, October 2010,
              <https://www.rfc-editor.org/info/rfc6021>.

   [RFC6241]  Enns, R., Ed., Bjorklund, M., Ed., Schoenwaelder, J., Ed.,
              and A. Bierman, Ed., "Network Configuration Protocol
              (NETCONF)", RFC 6241, DOI 10.17487/RFC6241, June 2011,
              <https://www.rfc-editor.org/info/rfc6241>.

   [RFC6536]  Bierman, A. and M. Bjorklund, "Network Configuration
              Protocol (NETCONF) Access Control Model", RFC 6536,
              DOI 10.17487/RFC6536, March 2012,
              <https://www.rfc-editor.org/info/rfc6536>.

   [RFC7223]  Bjorklund, M., "A YANG Data Model for Interface
              Management", RFC 7223, DOI 10.17487/RFC7223, May 2014,
              <https://www.rfc-editor.org/info/rfc7223>.





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   [RFC7224]  Bjorklund, M., "IANA Interface Type YANG Module",
              RFC 7224, DOI 10.17487/RFC7224, May 2014,
              <https://www.rfc-editor.org/info/rfc7224>.

   [RFC7277]  Bjorklund, M., "A YANG Data Model for IP Management",
              RFC 7277, DOI 10.17487/RFC7277, June 2014,
              <https://www.rfc-editor.org/info/rfc7277>.

   [RFC7317]  Bierman, A. and M. Bjorklund, "A YANG Data Model for
              System Management", RFC 7317, DOI 10.17487/RFC7317, August
              2014, <https://www.rfc-editor.org/info/rfc7317>.

   [RFC8040]  Bierman, A., Bjorklund, M., and K. Watsen, "RESTCONF
              Protocol", RFC 8040, DOI 10.17487/RFC8040, January 2017,
              <https://www.rfc-editor.org/info/rfc8040>.

Appendix A.  ".sid" file example

   The following .sid file (ietf-system@2014-08-06.sid) have been
   generated using the following yang modules:

   o  ietf-system@2014-08-06.yang

   o  ietf-yang-types@2013-07-15.yang

   o  ietf-inet-types@2013-07-15.yang

   o  ietf-netconf-acm@2012-02-22.yang

   o  iana-crypt-hash@2014-04-04.yang

   {
     "assignment-ranges": [
       {
         "entry-point": 1700,
         "size": 100
       }
     ],
     "module-name": "ietf-system",
     "module-revision": "2014-08-06",
     "items": [
       {
         "namespace": "module",
         "identifier": "ietf-system",
         "sid": 1700
       },
       {
         "namespace": "identity",



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         "identifier": "authentication-method",
         "sid": 1701
       },
       {
         "namespace": "identity",
         "identifier": "local-users",
         "sid": 1702
       },
       {
         "namespace": "identity",
         "identifier": "radius",
         "sid": 1703
       },
       {
         "namespace": "identity",
         "identifier": "radius-authentication-type",
         "sid": 1704
       },
       {
         "namespace": "identity",
         "identifier": "radius-chap",
         "sid": 1705
       },
       {
         "namespace": "identity",
         "identifier": "radius-pap",
         "sid": 1706
       },
       {
         "namespace": "feature",
         "identifier": "authentication",
         "sid": 1707
       },
       {
         "namespace": "feature",
         "identifier": "dns-udp-tcp-port",
         "sid": 1708
       },
       {
         "namespace": "feature",
         "identifier": "local-users",
         "sid": 1709
       },
       {
         "namespace": "feature",
         "identifier": "ntp",
         "sid": 1710
       },



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       {
         "namespace": "feature",
         "identifier": "ntp-udp-port",
         "sid": 1711
       },
       {
         "namespace": "feature",
         "identifier": "radius",
         "sid": 1712
       },
       {
         "namespace": "feature",
         "identifier": "radius-authentication",
         "sid": 1713
       },
       {
         "namespace": "feature",
         "identifier": "timezone-name",
         "sid": 1714
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:set-current-datetime",
         "sid": 1715
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:set-current-datetime/
                        current-datetime",
         "sid": 1716
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system",
         "sid": 1717
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-restart",
         "sid": 1718
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-shutdown",
         "sid": 1719
       },
       {
         "namespace": "data",



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         "identifier": "/ietf-system:system-state",
         "sid": 1720
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-state/clock",
         "sid": 1721
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-state/clock/boot-datetime",
         "sid": 1722
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-state/clock/
                        current-datetime",
         "sid": 1723
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-state/platform",
         "sid": 1724
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-state/platform/machine",
         "sid": 1725
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-state/platform/os-name",
         "sid": 1726
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-state/platform/os-release",
         "sid": 1727
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system-state/platform/os-version",
         "sid": 1728
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication",
         "sid": 1729



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       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication/user",
         "sid": 1730
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication/
                        user-authentication-order",
         "sid": 1731
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication/user/
                        authorized-key",
         "sid": 1732
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication/user/
                        authorized-key/algorithm",
         "sid": 1733
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication/user/
                        authorized-key/key-data",
         "sid": 1734
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication/user/
                        authorized-key/name",
         "sid": 1735
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication/user/
                        name",
         "sid": 1736
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/authentication/user/
                        password",
         "sid": 1737
       },



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       {
         "namespace": "data",
         "identifier": "/ietf-system:system/clock",
         "sid": 1738
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/clock/timezone-name",
         "sid": 1739
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/clock/timezone-utc-offset",
         "sid": 1740
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/contact",
         "sid": 1741
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver",
         "sid": 1742
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/options",
         "sid": 1743
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/options/
                        attempts",
         "sid": 1744
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/options/
                        timeout",
         "sid": 1745
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/search",
         "sid": 1746
       },
       {



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         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/server",
         "sid": 1747
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/server/name",
         "sid": 1748
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/server/
                        udp-and-tcp",
         "sid": 1749
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/server/
                        udp-and-tcp/address",
         "sid": 1750
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/dns-resolver/server/
                        udp-and-tcp/port",
         "sid": 1751
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/hostname",
         "sid": 1752
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/location",
         "sid": 1753
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp",
         "sid": 1754
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/enabled",
         "sid": 1755
       },
       {



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         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/server",
         "sid": 1756
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/server/
                        association-type",
         "sid": 1757
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/server/iburst",
         "sid": 1758
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/server/name",
         "sid": 1759
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/server/prefer",
         "sid": 1760
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/server/udp",
         "sid": 1761
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/server/udp/address",
         "sid": 1762
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/ntp/server/udp/port",
         "sid": 1763
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius",
         "sid": 1764
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/options",



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         "sid": 1765
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/options/attempts",
         "sid": 1766
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/options/timeout",
         "sid": 1767
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/server",
         "sid": 1768
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/server/
                        authentication-type",
         "sid": 1769
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/server/name",
         "sid": 1770
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/server/udp",
         "sid": 1771
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/server/udp/
                        address",
         "sid": 1772
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/server/udp/
                        authentication-port",
         "sid": 1773
       },
       {
         "namespace": "data",
         "identifier": "/ietf-system:system/radius/server/udp/



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                        shared-secret",
         "sid": 1774
       }
     ]
   }

Authors' Addresses

   Michel Veillette (editor)
   Trilliant Networks Inc.
   610 Rue du Luxembourg
   Granby, Quebec  J2J 2V2
   Canada

   Phone: +14503750556
   Email: michel.veillette@trilliant.com


   Alexander Pelov (editor)
   Acklio
   2bis rue de la Chataigneraie
   Cesson-Sevigne, Bretagne  35510
   France

   Email: a@ackl.io


























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