Internet-Draft Alfred S. Gilman draft-gilman-news-url-02 March 9, 1998 Expires six months after above date The 'news' URL scheme 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 ftp.is.co.za (Africa), nic.nordu.net (Europe), munnari.oz.au (Pacific Rim), ds.internic.net (US East Coast), or ftp.isi.edu (US West Coast). Abstract This document defines the format of Uniform Resource Locators (URLs) identifying news messages and groups. The syntax of 'news' URLs from RFC 1738 is extended to allow specification of the site from which the message is to be sought. This combines into the 'news' scheme enough capability so that the previously-proposed 'nntp' scheme can be retired and URL usage simplified. An 'snews' variant is also defined which refers to a form of secure service which is in current use and involves a different default port. 1. Introduction The news URL scheme is used to designate a message or a set of messages circulating through the Internet by methods compatible with the practices followed by the Usenet community. In its simplest form, a news URL contains a Usenet newsgroup name. Further capabilities are the ability to designate an unique message as the located resource, to specify that the News server at a particular site is to be queried for the resource identified and to request secure dialog via the variant snews scheme name. This draft is one of a suite of documents intended replace RFC 1738 [3], "Uniform Resource Locators", and RFC 1808 [4], "Relative Uniform Resource Locators". The suite is composed of a general document [RFC URI SYNTAX] for all URL schemes and scheme-specific documents for each scheme. 2. Syntax of a news URL Following the syntax conventions of [RFC URL SYNTAX], a news URL has the form: newsURL = scheme ":" [ news-server ] [ refbygroup | message ] scheme = "news" | "nntp" news-server = "//" server "/" refbygroup = group [ "/" messageno [ "-" messageno ] ] message = local-part "@" domain Sites take the form defined for the generic URL syntax in section 3.2.2 of [RFC-URI-SYNTAX]. Messages take the form specified for the value of a Message-ID field in RFC 822 [1] or RFC 1036 [2], without the leading "<" or trailing ">". Note that the refbygroup and message cases are distinguished by the absense in the first case and presence in the latter case of one and only one commercial at sign "@". Groups take the form of a dotted name of a News group as allowed in the value of the Newsgroups header field defined in RFC 1036. Messagenos take the form of an integer message number as numbered by a particular server. As these numbers will vary between copies of the same message available from different servers, reference by message ID is preferred to reference to messages by means of these numbers. Note that all URLs of this scheme are in the category of absolute URLs, in the terms of [RFC URI SYNTAX]. 3. Semantics and operations The default port (in server) is 119. This is the default port for NNTP service. A news URL designates a message or message-carrying subchannel known as a newsgroup. When a news URL is activated, message reading and writing from and to News is initiated, if that service is available. If an individual message has been identified, interaction starts by reading that message. If an individual group or range of messages in such a group had been identified, interaction starts by reading an index of messages. If no message or group is identified, interaction starts by reading an index of groups. No immediate write or PUT of a message is performed when a news URL is activated. Note that user agents may extend the ability to refer to groups by use of "*" as a string wild-card. 4. Examples An URL to read a newsgroup from anywhere (usually locally): An URL to read a specific message from anywhere (usually locally): An URL to read a specific message from a designated site: An URL to read a newsgroup from a designated site: 5. The 'snews' variant. The port number of 563 has been registered with IANA for the provision of NNTP service over TLS/SSL. Access to such services is identified by URLs in the form defined here with 'scheme' spelled as 'snews'. This current usage may be deprecated in the future for security reasons should suitable provisions for security protocol negotiation over the standard NNTP port of 119 be standardized in the future. 6. Acknowledgements This document was derived from RFC 1738 [3]; the acknowledgements from that specification still apply. 7. References [1] Crocker, D., "Standard for the Format of ARPA Internet Text Messages", RFC 822, University of Delaware, August 1982. [2] Horton, M. and R. Adams, "Standard For Interchange of USENET Messages", RFC 1036, AT&T Bell Laboratories, Center for Seismic Studies, December 1987. [3] Berners-Lee, T., Masinter, L., and M. McCahill, Editors, "Uniform Resource Locators (URL)", RFC 1738, CERN, Xerox Corporation, University of Minnesota, December 1994. [4] Fielding, R., "Relative Uniform Resource Locators", RFC 1808, UC Irvine, June 1995. [RFC-URI-SYNTAX] Berners-Lee, T., Fielding, R., Masinter L., "Uniform Resource Locators (URL): Generic Syntax and Semantics", Work in Progress , MIT/LCS, U.C. Irvine, Xerox Corporation, Mar 1998. Appendix A. Changes from RFC 1738 RFC 1738 defined two distinct URL schemes designated news and nntp. Both schemes, however, accessed the same pool of News message traffic. In no case was the scheme name significant in distinguishing references to different messages or to different groups. Various implementations have blurred the distinction by extending the syntax of news to include explicit remote references including designation of a site. This draft provides a unified syntax for a graceful migration to the use of news and not nntp as scheme name. B. Author contact information: Alfred S. Gilman 1101 S. Arlington Ridge Rd. Unit 712 Arlington VA 22202-1926 asgilman@access.digex.net