5131
PROPOSED STANDARD

A MIB Textual Convention for Language Tags

Authors: D. McWalter
Date: December 2007
Working Group: NON WORKING GROUP
Stream: IETF

Abstract

This MIB module defines a textual convention to represent BCP 47 language tags. The intent is that this textual convention will be imported and used in MIB modules that would otherwise define their own representation. [STANDARDS-TRACK]

RFC 5131: A MIB Textual Convention for Language Tags [RFC Home] [TEXT|PDF|HTML] [Tracker] [IPR] [Info page]

PROPOSED STANDARD
Network Working Group                                   D. McWalter, Ed.
Request for Comments: 5131                           Data Connection Ltd
Category: Standards Track                                  December 2007


               <span class="h1">A MIB Textual Convention for Language Tags</span>

Status of This Memo

   This document specifies an Internet standards track protocol for the
   Internet community, and requests discussion and suggestions for
   improvements.  Please refer to the current edition of the "Internet
   Official Protocol Standards" (STD 1) for the standardization state
   and status of this protocol.  Distribution of this memo is unlimited.

Abstract

   This MIB module defines a textual convention to represent <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a>
   language tags.  The intent is that this textual convention will be
   imported and used in MIB modules that would otherwise define their
   own representation.

Table of Contents

   <a href="#section-1">1</a>.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . . <a href="#page-2">2</a>
   <a href="#section-2">2</a>.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . . . <a href="#page-2">2</a>
   <a href="#section-3">3</a>.  The Internet-Standard Management Framework  . . . . . . . . . . <a href="#page-2">2</a>
   <a href="#section-4">4</a>.  Definitions . . . . . . . . . . . . . . . . . . . . . . . . . . <a href="#page-3">3</a>
   <a href="#section-5">5</a>.  Security Considerations . . . . . . . . . . . . . . . . . . . . <a href="#page-4">4</a>
   <a href="#section-6">6</a>.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . . <a href="#page-4">4</a>
   <a href="#section-7">7</a>.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . . <a href="#page-4">4</a>
   <a href="#section-8">8</a>.  References  . . . . . . . . . . . . . . . . . . . . . . . . . . <a href="#page-4">4</a>
     <a href="#section-8.1">8.1</a>.  Normative References  . . . . . . . . . . . . . . . . . . . <a href="#page-4">4</a>
     <a href="#section-8.2">8.2</a>.  Informative References  . . . . . . . . . . . . . . . . . . <a href="#page-5">5</a>

















<span class="grey">McWalter                    Standards Track                     [Page 1]</span>

<span id="page-2" ></span>
<span class="grey"><a href="./rfc5131">RFC 5131</a>                     LANGTAG TC MIB                December 2007</span>


<span class="h2"><a class="selflink" id="section-1" href="#section-1">1</a>.  Introduction</span>

   This memo defines a portion of the Management Information Base (MIB)
   for use with network management protocols in the Internet community.
   It defines a textual convention to represent <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a> [<a href="./rfc4646" title=""Tags for Identifying Languages"">RFC4646</a>]
   language tags.

   The LangTag TEXTUAL-CONVENTION defined by this RFC replaces the
   similar LanguageTag TEXTUAL-CONVENTION defined by <a href="./rfc2932">RFC 2932</a> [<a href="./rfc2932" title=""IPv4 Multicast Routing MIB"">RFC2932</a>].

   The old LanguageTag TEXTUAL-CONVENTION is used by some existing MIB
   modules.  New MIB modules should use the LangTag TEXTUAL-CONVENTION,
   which has been created (and is to be preferred) for the following
   reasons:

   o  Its syntax description is current, and is more comprehensive.

   o  It is short enough to use as an index object without subtyping,
      yet is of adequate length to represent any language tag in
      practice.

   o  It is provided in a dedicated MIB module to simplify module
      dependencies.

   It is not possible to apply changes in syntax and length to an
   existing textual convention.  This is why the creation of a new
   textual convention with a new name was necessary.

<span class="h2"><a class="selflink" id="section-2" href="#section-2">2</a>.  Terminology</span>

   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 <a href="./rfc2119">RFC 2119</a> [<a href="./rfc2119" title=""Key words for use in RFCs to Indicate Requirement Levels"">RFC2119</a>].

<span class="h2"><a class="selflink" id="section-3" href="#section-3">3</a>.  The Internet-Standard Management Framework</span>

   For a detailed overview of the documents that describe the current
   Internet-Standard Management Framework, please refer to <a href="./rfc3410#section-7">section 7 of
   RFC 3410</a> [<a href="./rfc3410" title=""Introduction and Applicability Statements for Internet- Standard Management Framework"">RFC3410</a>].

   Managed objects are accessed via a virtual information store, termed
   the Management Information Base or MIB.  MIB objects are generally
   accessed through the Simple Network Management Protocol (SNMP).
   Objects in the MIB are defined using the mechanisms defined in the
   Structure of Management Information (SMI).  This memo specifies a MIB
   module that is compliant to the SMIv2, which is described in STD 58,
   <a href="./rfc2578">RFC 2578</a> [<a href="./rfc2578" title=""Structure of Management Information Version 2 (SMIv2)"">RFC2578</a>], STD 58, <a href="./rfc2579">RFC 2579</a> [<a href="./rfc2579" title=""Textual Conventions for SMIv2"">RFC2579</a>] and STD 58, <a href="./rfc2580">RFC 2580</a>
   [<a href="./rfc2580" title=""Conformance Statements for SMIv2"">RFC2580</a>].



<span class="grey">McWalter                    Standards Track                     [Page 2]</span>

<span id="page-3" ></span>
<span class="grey"><a href="./rfc5131">RFC 5131</a>                     LANGTAG TC MIB                December 2007</span>


<span class="h2"><a class="selflink" id="section-4" href="#section-4">4</a>.  Definitions</span>

LANGTAG-TC-MIB DEFINITIONS ::= BEGIN

IMPORTS
    MODULE-IDENTITY, mib-2             FROM SNMPv2-SMI      -- [<a href="./rfc2578" title=""Structure of Management Information Version 2 (SMIv2)"">RFC2578</a>]
    TEXTUAL-CONVENTION                 FROM SNMPv2-TC;      -- [<a href="./rfc2579" title=""Textual Conventions for SMIv2"">RFC2579</a>]

langTagTcMIB MODULE-IDENTITY
    LAST-UPDATED "200711090000Z" -- 9 November 2007
    ORGANIZATION "IETF Operations and Management (OPS) Area"
    CONTACT-INFO "EMail: [email protected]
                  Home page: <a href="http://www.ops.ietf.org/">http://www.ops.ietf.org/</a>"
    DESCRIPTION
            "This MIB module defines a textual convention for
            representing <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a> language tags."
    REVISION     "200711090000Z" -- 9 November 2007
    DESCRIPTION
           "Initial revision, published as <a href="./rfc5131">RFC 5131</a>.

            Copyright (C) The IETF Trust (2007).  This version of this
            MIB module is part of <a href="./rfc5131">RFC 5131</a>; see the RFC itself for full
            legal notices."
    ::= { mib-2 165 }

LangTag ::= TEXTUAL-CONVENTION
   DISPLAY-HINT "1a"
   STATUS      current
   DESCRIPTION
            "A language tag, constructed in accordance with <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a>.

            Only lowercase characters are allowed.  The purpose of this
            restriction is to provide unique language tags for use as
            indexes.  <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a> recommends case conventions for user
            interfaces, but objects using this TEXTUAL-CONVENTION MUST
            use only lowercase.

            Values MUST be well-formed language tags, in conformance
            with the definition of well-formed tags in <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a>.  An
            implementation MAY further limit the values it accepts to
            those permitted by a 'validating' processor, as defined in
            <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a>.

            In theory, <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a> language tags are of unlimited length.
            The language tag described in this TEXTUAL-CONVENTION is of
            limited length.  The analysis of language tag lengths in <a href="https://www.rfc-editor.org/bcp/bcp47">BCP</a>
            <a href="https://www.rfc-editor.org/bcp/bcp47">47</a> confirms that this limit will not pose a problem in
            practice.  In particular, this length is greater than the



<span class="grey">McWalter                    Standards Track                     [Page 3]</span>

<span id="page-4" ></span>
<span class="grey"><a href="./rfc5131">RFC 5131</a>                     LANGTAG TC MIB                December 2007</span>


            minimum requirements set out in <a href="#section-4.3.1">Section 4.3.1</a>.

            A zero-length language tag is not a valid language tag.
            This can be used to express 'language tag absent' where
            required, for example, when used as an index field."
   REFERENCE "<a href="./rfc4646">RFC 4646</a> <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a>"
   SYNTAX      OCTET STRING (SIZE (0 | 2..63))

END

<span class="h2"><a class="selflink" id="section-5" href="#section-5">5</a>.  Security Considerations</span>

   This MIB module does not define any management objects.  Instead, it
   defines a textual convention that may be imported by other MIB
   modules and used for object definitions.

   Meaningful security considerations can only be written in the MIB
   modules that define management objects.  This document therefore has
   no impact on the security of the Internet.

<span class="h2"><a class="selflink" id="section-6" href="#section-6">6</a>.  IANA Considerations</span>

   LANGTAG-TC-MIB is rooted under the mib-2 subtree.  IANA has assigned
   { mib-2 165 } to the LANGTAG-TC-MIB module specified in this
   document.

<span class="h2"><a class="selflink" id="section-7" href="#section-7">7</a>.  Acknowledgements</span>

   This MIB module is a reworking of existing material from <a href="./rfc2932">RFC 2932</a>.

   This module was generated by editing together contributions from
   Randy Presuhn, Dan Romascanu, Bill Fenner, Juergen Schoenwaelder,
   Bert Wijnen, Doug Ewell, and Ira McDonald.

<span class="h2"><a class="selflink" id="section-8" href="#section-8">8</a>.  References</span>

<span class="h3"><a class="selflink" id="section-8.1" href="#section-8.1">8.1</a>.  Normative References</span>

   [<a id="ref-RFC2119">RFC2119</a>]  Bradner, S., "Key words for use in RFCs to Indicate
              Requirement Levels", <a href="https://www.rfc-editor.org/bcp/bcp14">BCP 14</a>, <a href="./rfc2119">RFC 2119</a>, March 1997.

   [<a id="ref-RFC2578">RFC2578</a>]  McCloghrie, K., Ed., Perkins, D., Ed., and J.
              Schoenwaelder, Ed., "Structure of Management Information
              Version 2 (SMIv2)", STD 58, <a href="./rfc2578">RFC 2578</a>, April 1999.

   [<a id="ref-RFC2579">RFC2579</a>]  McCloghrie, K., Ed., Perkins, D., Ed., and J.
              Schoenwaelder, Ed., "Textual Conventions for SMIv2",
              STD 58, <a href="./rfc2579">RFC 2579</a>, April 1999.



<span class="grey">McWalter                    Standards Track                     [Page 4]</span>

<span id="page-5" ></span>
<span class="grey"><a href="./rfc5131">RFC 5131</a>                     LANGTAG TC MIB                December 2007</span>


   [<a id="ref-RFC2580">RFC2580</a>]  McCloghrie, K., Perkins, D., and J. Schoenwaelder,
              "Conformance Statements for SMIv2", STD 58, <a href="./rfc2580">RFC 2580</a>,
              April 1999.

   [<a id="ref-RFC4646">RFC4646</a>]  Phillips, A. and M. Davis, "Tags for Identifying
              Languages", <a href="https://www.rfc-editor.org/bcp/bcp47">BCP 47</a>, <a href="./rfc4646">RFC 4646</a>, September 2006.

<span class="h3"><a class="selflink" id="section-8.2" href="#section-8.2">8.2</a>.  Informative References</span>

   [<a id="ref-RFC2932">RFC2932</a>]  McCloghrie, K., Farinacci, D., and D. Thaler, "IPv4
              Multicast Routing MIB", <a href="./rfc2932">RFC 2932</a>, October 2000.

   [<a id="ref-RFC3410">RFC3410</a>]  Case, J., Mundy, R., Partain, D., and B. Stewart,
              "Introduction and Applicability Statements for Internet-
              Standard Management Framework", <a href="./rfc3410">RFC 3410</a>, December 2002.

Author's Address

   David McWalter (editor)
   Data Connection Ltd
   100 Church Street
   Enfield  EN2 6BQ
   United Kingdom

   EMail: [email protected]


























<span class="grey">McWalter                    Standards Track                     [Page 5]</span>

<span id="page-6" ></span>
<span class="grey"><a href="./rfc5131">RFC 5131</a>                     LANGTAG TC MIB                December 2007</span>


Full Copyright Statement

   Copyright (C) The IETF Trust (2007).

   This document is subject to the rights, licenses and restrictions
   contained in <a href="https://www.rfc-editor.org/bcp/bcp78">BCP 78</a>, and except as set forth therein, the authors
   retain all their rights.

   This document and the information contained herein are provided on an
   "AS IS" basis and THE CONTRIBUTOR, THE ORGANIZATION HE/SHE REPRESENTS
   OR IS SPONSORED BY (IF ANY), THE INTERNET SOCIETY, THE IETF TRUST AND
   THE INTERNET ENGINEERING TASK FORCE DISCLAIM ALL WARRANTIES, EXPRESS
   OR IMPLIED, INCLUDING BUT NOT LIMITED TO ANY WARRANTY THAT THE USE OF
   THE INFORMATION HEREIN WILL NOT INFRINGE ANY RIGHTS OR ANY IMPLIED
   WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE.

Intellectual Property

   The IETF takes no position regarding the validity or scope of any
   Intellectual Property Rights or other rights that might be claimed to
   pertain to the implementation or use of the technology described in
   this document or the extent to which any license under such rights
   might or might not be available; nor does it represent that it has
   made any independent effort to identify any such rights.  Information
   on the procedures with respect to rights in RFC documents can be
   found in <a href="https://www.rfc-editor.org/bcp/bcp78">BCP 78</a> and <a href="https://www.rfc-editor.org/bcp/bcp79">BCP 79</a>.

   Copies of IPR disclosures made to the IETF Secretariat and any
   assurances of licenses to be made available, or the result of an
   attempt made to obtain a general license or permission for the use of
   such proprietary rights by implementers or users of this
   specification can be obtained from the IETF on-line IPR repository at
   <a href="http://www.ietf.org/ipr">http://www.ietf.org/ipr</a>.

   The IETF invites any interested party to bring to its attention any
   copyrights, patents or patent applications, or other proprietary
   rights that may cover technology that may be required to implement
   this standard.  Please address the information to the IETF at
   [email protected].












McWalter                    Standards Track                     [Page 6]

Additional Resources