X.500 labeledURL Attribute Type Mark Smith INTERNET-DRAFT University of Michigan 8 November 1994 Definition of an X.500 Attribute Type and Object Class to Hold Uniform Resource Locators (URLs) Filename: draft-ietf-asid-x500-url-00.txt Status of this Memo This document is an Internet-Draft. 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.'' To learn the current status of any Internet-Draft, please check the ``1id-abstracts.txt'' listing contained in the Internet- Drafts Shadow Directories on ds.internic.net (US East Coast), nic.nordu.net (Europe), ftp.isi.edu (US West Coast), or munnari.oz.au (Pacific Rim). Distribution of this memo is unlimited. Editorial comments should be sent to the author (mcs@umich.edu). Technical discussion will take place on the IETF ASID mailing list (ietf-asid@umich.edu). This Internet Draft expires May 12th, 1995. Abstract Uniform Resource Locators (URLs) as defined by [1] are being widely used to specify the location of Internet resources. There is an urgent need to be able to include URLs in the X.500 [2,3] Directory. A number of independent groups are already experimenting with the inclusion of URLs in the X.500 Directory through the use of existing or newly defined attribute types. This document builds on the experimentation to date and defines a new attribute type and an auxiliary object class to allow URLs to be included in X.500 Directory entries in a standard way. It is intended that the schema elements defined in this document will be progressed according to the process defined by the Internet X.500 Schema Working Group [4]. Smith [Page 1] INTERNET-DRAFT X.500 labeledURL Attribute Type 8 November 1994 Schema Definition of labeledURL Attribute Type Name: labeledURL ShortName: Description: Uniform Resource Locator with optional label OID: umichAttributeType.41 (1.3.6.1.4.1.250.1.41) Syntax: caseExactString SizeRestriction: None SingleValued: False Discussion of the labeledURL Attribute Type The labeledURL attribute type has the caseExactString syntax (since URLs are case-sensitive) and it is multivalued. Values placed in the attribute should consist of a URL, optionally followed by one or more space characters and a label. Since space characters are not allowed to appear un-encoded in URLs, there is no ambiguity about where the label begins. The URL portion must comply with the URL specification [1]. Multiple labeledURL values will generally indicate different resources that are all related to the X.500 object, but may indicate different locations for the same resource. The label is used to describe the resource to which the URL points, and is intended as a friendly name fit for human consumption. This document does not propose any specific syntax for the label part. Note that in some cases it may be helpful to include in the label some indication of the kind and/or size of the resource referenced by the URL. Note that the label may include any characters allowed by the caseExactString syntax, but that the use of non-IA5 (non-ASCII) characters is discouraged as not all directory clients may handle them in the same manner. Some examples of valid labeledURL values (the first does not have a label): ftp://ds.internic.net/rfc/rfc1588.txt http://www.umich.edu/ University of Michigan Home Page http://champagne.inria.fr/Unites/rennes.gif Rennes [photo] Smith [Page 2] INTERNET-DRAFT X.500 labeledURL Attribute Type 8 November 1994 Schema Definition of labeledURLObject Object Class Name: labeledURLObject Description: object that contains the labeledURL attribute type OID: umichObjectClass.14 (1.3.6.1.4.1.250.3.14) SubclassOf: top MustContain: MayContain: labeledURL Discussion of the labeledURLObject Object Class The labeledURLObject class is a subclass of top and may contain the labeledURL attribute. The intent is that this object class can be added to existing objects to allow for inclusion of labeledURL values. This approach does not preclude including the labeledURL attribute type directly in other object classes as appropriate. References [1] Berners-Lee, T., Masinter, L., and McCahill, M., "Uniform Resource Locators (URL)", Internet Draft (Work In Progress) of the IETF URI Working Group, [2] The Directory: Overview of Concepts, Models and Service. CCITT Recommendation X.500, 1988. [3] Information Processing Systems -- Open Systems Interconnection -- The Directory: Overview of Concepts, Models and Service. ISO/IEC JTC 1/SC21; International Standard 9594-1, 1988. [4] Howes, T., Rossen, K., Sataluri, S., and Wright, R., "Procedures for Formalizing, Evolving, and Maintaining the Internet X.500 Directory Schema", Internet Draft (Work In Progress) of the Schema Working Group, Security Considerations Security considerations are not discussed in this memo. Acknowledgments Paul-Andre Pays, Martijn Koster, Tim Howes, Rakesh Patel, and Russ Wright provided invaluable assistance in the creation of this document. Smith [Page 3] INTERNET-DRAFT X.500 labeledURL Attribute Type 8 November 1994 Author's Address Mark Smith University of Michigan Information Technology Division 535 W. William St. Ann Arbor, MI 48103-4943, USA Phone: +1 313 764-2277 Fax: +1 313 765-5140 EMail: mcs@umich.edu This Internet Draft expires May 12th, 1995. Smith [Page 4]