Movatterモバイル変換

Network Working Group                                   D. McWalter, Ed.Request for Comments: 5131                           Data Connection LtdCategory: Standards Track                                  December 2007A MIB Textual Convention for Language TagsStatus 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 representBCP 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.Table of Contents1.  Introduction  . . . . . . . . . . . . . . . . . . . . . . . . .22.  Terminology . . . . . . . . . . . . . . . . . . . . . . . . . .23.  The Internet-Standard Management Framework  . . . . . . . . . .24.  Definitions . . . . . . . . . . . . . . . . . . . . . . . . . .35.  Security Considerations . . . . . . . . . . . . . . . . . . . .46.  IANA Considerations . . . . . . . . . . . . . . . . . . . . . .47.  Acknowledgements  . . . . . . . . . . . . . . . . . . . . . . .48.  References  . . . . . . . . . . . . . . . . . . . . . . . . . .48.1.  Normative References  . . . . . . . . . . . . . . . . . . .48.2.  Informative References  . . . . . . . . . . . . . . . . . .5McWalter                    Standards Track                     [Page 1]

RFC 5131                     LANGTAG TC MIB                December 20071.  Introduction   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 representBCP 47 [RFC4646]   language tags.   The LangTag TEXTUAL-CONVENTION defined by this RFC replaces the   similar LanguageTag TEXTUAL-CONVENTION defined byRFC 2932 [RFC2932].   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.2.  Terminology   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 inRFC 2119 [RFC2119].3.  The Internet-Standard Management Framework   For a detailed overview of the documents that describe the current   Internet-Standard Management Framework, please refer tosection 7 of   RFC 3410 [RFC3410].   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,RFC 2578 [RFC2578], STD 58,RFC 2579 [RFC2579] and STD 58,RFC 2580   [RFC2580].McWalter                    Standards Track                     [Page 2]

RFC 5131                     LANGTAG TC MIB                December 20074.  DefinitionsLANGTAG-TC-MIB DEFINITIONS ::= BEGINIMPORTS    MODULE-IDENTITY, mib-2             FROM SNMPv2-SMI      -- [RFC2578]    TEXTUAL-CONVENTION                 FROM SNMPv2-TC;      -- [RFC2579]langTagTcMIB MODULE-IDENTITY    LAST-UPDATED "200711090000Z" -- 9 November 2007    ORGANIZATION "IETF Operations and Management (OPS) Area"    CONTACT-INFO "EMail: ops-area@ietf.org                  Home page:http://www.ops.ietf.org/"    DESCRIPTION            "This MIB module defines a textual convention for            representingBCP 47 language tags."    REVISION     "200711090000Z" -- 9 November 2007    DESCRIPTION           "Initial revision, published asRFC 5131.            Copyright (C) The IETF Trust (2007).  This version of this            MIB module is part ofRFC 5131; 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 withBCP 47.            Only lowercase characters are allowed.  The purpose of this            restriction is to provide unique language tags for use as            indexes.BCP 47 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 inBCP 47.  An            implementation MAY further limit the values it accepts to            those permitted by a 'validating' processor, as defined inBCP 47.            In theory,BCP 47 language tags are of unlimited length.            The language tag described in this TEXTUAL-CONVENTION is of            limited length.  The analysis of language tag lengths inBCP47 confirms that this limit will not pose a problem in            practice.  In particular, this length is greater than theMcWalter                    Standards Track                     [Page 3]

RFC 5131                     LANGTAG TC MIB                December 2007            minimum requirements set out inSection 4.3.1.            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 "RFC 4646BCP 47"   SYNTAX      OCTET STRING (SIZE (0 | 2..63))END5.  Security Considerations   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.6.  IANA Considerations   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.7.  Acknowledgements   This MIB module is a reworking of existing material fromRFC 2932.   This module was generated by editing together contributions from   Randy Presuhn, Dan Romascanu, Bill Fenner, Juergen Schoenwaelder,   Bert Wijnen, Doug Ewell, and Ira McDonald.8.  References8.1.  Normative References   [RFC2119]  Bradner, S., "Key words for use in RFCs to Indicate              Requirement Levels",BCP 14,RFC 2119, March 1997.   [RFC2578]  McCloghrie, K., Ed., Perkins, D., Ed., and J.              Schoenwaelder, Ed., "Structure of Management Information              Version 2 (SMIv2)", STD 58,RFC 2578, April 1999.   [RFC2579]  McCloghrie, K., Ed., Perkins, D., Ed., and J.              Schoenwaelder, Ed., "Textual Conventions for SMIv2",              STD 58,RFC 2579, April 1999.McWalter                    Standards Track                     [Page 4]

RFC 5131                     LANGTAG TC MIB                December 2007   [RFC2580]  McCloghrie, K., Perkins, D., and J. Schoenwaelder,              "Conformance Statements for SMIv2", STD 58,RFC 2580,              April 1999.   [RFC4646]  Phillips, A. and M. Davis, "Tags for Identifying              Languages",BCP 47,RFC 4646, September 2006.8.2.  Informative References   [RFC2932]  McCloghrie, K., Farinacci, D., and D. Thaler, "IPv4              Multicast Routing MIB",RFC 2932, October 2000.   [RFC3410]  Case, J., Mundy, R., Partain, D., and B. Stewart,              "Introduction and Applicability Statements for Internet-              Standard Management Framework",RFC 3410, December 2002.Author's Address   David McWalter (editor)   Data Connection Ltd   100 Church Street   Enfield  EN2 6BQ   United Kingdom   EMail: dmcw@dataconnection.comMcWalter                    Standards Track                     [Page 5]

RFC 5131                     LANGTAG TC MIB                December 2007Full Copyright Statement   Copyright (C) The IETF Trust (2007).   This document is subject to the rights, licenses and restrictions   contained inBCP 78, 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 inBCP 78 andBCP 79.   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 athttp://www.ietf.org/ipr.   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   ietf-ipr@ietf.org.McWalter                    Standards Track                     [Page 6]