Network Working Group K. Zeilenga Request for Comments: 3674 OpenLDAP Foundation Category: Standards Track December 2003 Feature Discovery in Lightweight Directory Access Protocol (LDAP) 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. Copyright Notice Copyright (C) The Internet Society (2003). All Rights Reserved.
AbstractThe Lightweight Directory Access Protocol (LDAP) is an extensible protocol with numerous elective features. This document introduces a general mechanism for discovery of elective features and extensions which cannot be discovered using existing mechanisms. RFC3377] is an extensible protocol with numerous elective features. LDAP provides mechanisms for a client to discover supported protocol versions, controls, extended operations, Simple Authentication and Security Layer (SASL) mechanisms, and subschema information. However, these mechanisms are not designed to support general feature discovery. This document describes a simple, general-purpose mechanism which clients may use to discover the set of elective features supported by a server. For example, this mechanism could be used by a client to discover whether or not the server supports requests for all operational attributes, e.g., "+" [RFC3673]. As another example, this mechanism could be used to discover absolute true, e.g., "(&)" and false, e.g., "(|)", search filters [T-F] support. This document extends the LDAP Protocol Mechanism registry [RFC3383] to support registration of values of the supportedFeatures attribute. This registry is managed by the Internet Assigned Numbers Authority (IANA).
Schema definitions are provided using LDAP description formats [RFC2252]. Definitions provided here are formatted (line wrapped) for readability. 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 BCP 14 [RFC2119]. RFC3383]. The word "Feature" should be placed in the usage field of the submitted LDAP Protocol Mechanism template. The 'supportedFeatures' attribute type is described as follows: ( 22.214.171.124.4.1.4126.96.36.199 NAME 'supportedFeatures' DESC 'features supported by the server' EQUALITY objectIdentifierMatch SYNTAX 188.8.131.52.4.1.14184.108.40.206.38 USAGE dSAOperation ) Servers MUST be capable of recognizing this attribute type by the name 'supportedFeatures'. Servers MAY recognize the attribute type by other names.
The IETF invites any interested party to bring to its attention any copyrights, patents or patent applications, or other proprietary rights which may cover technology that may be required to practice this standard. Please address the information to the IETF Executive Director. [RFC2119] Bradner, S., "Key words for use in RFCs to Indicate Requirement Levels", BCP 14, RFC 2119, March 1997. [RFC2252] Wahl, M., Coulbeck, A., Howes, T. and S. Kille, "Lightweight Directory Access Protocol (v3): Attribute Syntax Definitions", RFC 2252, December 1997. [RFC3377] Hodges, J. and R. Morgan, "Lightweight Directory Access Protocol (v3): Technical Specification", RFC 3377, September 2002. [RFC3383] Zeilenga, K., "Internet Assigned Numbers Authority (IANA) Considerations for Lightweight Directory Access Protocol (LDAP)", BCP 64, RFC 3383, September 2002. [RFC3673] Zeilenga, K., "Lightweight Directory Access Protocol version 3 (LDAPv3): All Operational Attributes", RFC 3673, December 2003. [T-F] Zeilenga, K., "LDAP True/False Filters", Work in Progress. [ASSIGN] OpenLDAP Foundation, "OpenLDAP OID Delegations", http://www.openldap.org/foundation/oid-delegate.txt. [PRIVATE] IANA, "Private Enterprise Numbers", http://www.iana.org/assignments/enterprise-numbers.
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