INTERNET-DRAFT Charles H. Lindsey Standards Track University of Manchester May 2005 The news and nntp URI Schemes Status of this Memo By submitting this Internet-Draft, each author represents that any applicable patent or other IPR claims of which he or she is aware have been or will be disclosed, and any of which he or she becomes aware will be disclosed, in accordance with Section 6 of BCP 79. 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." The list of current Internet-Drafts can be accessed at http://www.ietf.org/ietf/1id-abstracts.html. The list of Internet-Draft Shadow Directories can be accessed at http://www.ietf.org/shadow.html. This Internet-Draft will expire in November 2005. Abstract This document specifies the news and nntp Uniform Resource Identifier (URI) schemes that were originally specified in [RFC 1738]. The purpose of this document is to allow [RFC 1738] to be made obsolete while keeping the information about the scheme on standards track. It is based on the earlier draft-hoffman-news-nntp-uri-04.txt written by Paul Hoffman. C. H. Lindsey [Page 1] The news and nntp URI Schemes May 2005 Table of Contents 1. Introduction .................................................. 3 2. The News URI Scheme ........................................... 3 2.1. The newsURI contains an
......................... 4 2.2. The newsURI contains a ....................... 4 3. The nntp URI scheme ........................................... 4 3.1. The range is a single .................... 5 3.2. The range encompasses more than a single ......................................................... 5 4. Security Considerations ....................................... 5 5. Normative References .......................................... 5 6. Informative References ........................................ 5 7. Acknowledgements .............................................. 6 8. Contact Address ............................................... 6 Notices ........................................................... 6 C. H. Lindsey [Page 2] The news and nntp URI Schemes May 2005 1. Introduction URIs are defined in [RFC 3986]. That document also specifies how to define schemes for URIs. The first definition for many URI schemes appeared in [RFC 1738]. Because that document has been made obsolete, this document copies and adapts the news and nntp URI schemes from it to allow that material to remain on standards track. NOTE: the definitions for the news and nntp URI schemes given here are significant updates from [RFC 1738] based on modern usage of these schemes. The keywords "MUST", "SHOULD" and "MAY" are to be interpreted as described in [RFC 2119]. Syntax is described using the ABNF notation described in [RFC 2234]. 2. The News URI Scheme The news URI scheme is used to refer to either news groups or individual Netnews articles, as defined in [RFC 1036]. The news URI takes the form: newsURI = "news:" ( article / collection ) article = [ news-server "/" ] message-id collection = [ news-server "/" ] wildmat / [ news-server [ "/" ] ] news-server = "//" authority message-id = printable-ascii "@" printable-ascii newsgroup-name = %x22-29 / %x2B / %x2D-3E / %x40-5A / %x5E-7E ; excludes "*" "," "?" "[" " printable-ascii = 1*( %d33-61 / %d63-126 ) ; excludes ">" is defined in [RFC 3986], and provides for a , a (defaulting to 119 in this scheme) and possibly a . is defined in [NNTP], and provides for a single , or for a collection of s separated by ','s and using '*' and '?' for wild cards and '!' for negation. Within a or a , the characters '%', '@', '/' and '#' are reserved and MUST be %-encoded if they occur. All other characters MAY be used freely to represent themselves. It is not precluded that future extensions for internationalized s may permit octets outside of the given ranges, in which case they too MUST be %-encoded (except perhaps when used in an IRI [RFC 3987]). If no is specified, the resources are to be retrieved from whatever server has been configured for local use. C. H. Lindsey [Page 3] The news and nntp URI Schemes May 2005 2.1. The newsURI contains an
A corresponds to the of [RFC 2822] and to the Message-ID of section 2.1.5 of [RFC 1036], but without the enclosing "<" and ">". It is intended to be the message identifier of an actual Netnews article and hence will in practice conform to the syntax defined in [RFC 1036] or in any subsequent standard for Netnews articles. Observe the delimiter "@" which enables an
to be distinguished from a . The resource retrieved by this URI is the Netnews article with the given . Message identifiers are required to be globally unique, so the same article should be obtained whatever server is accessed for that purpose (provided the server in question has that article available). 2.2. The newsURI contains a Any contained in or implied by any is intended to be that of an existing newsgroup, such as "comp.lang.perl.modules", and hence will in practice conform to the syntax defined in [RFC 1036] or in any subsequent standard for Netnews articles. If the in the consists of just a single , the resource retrieved by this URI is some means to gain access to the articles in the given that are available from the given (usually by invoking a suitable news reading agent initialized to access that group). If the in the identifies a collection of newsgroups, the resource retrieved by this URI is some means to gain access to all of those newsgroups which are available from the given (usually by invoking a suitable news reading agent). If the contains no at all, the effect is the same as that of the "*", meaning "all available newsgroups". 3. The nntp URI scheme The nntp URI scheme is used to retrieve individual articles via the NNTP protocol [NNTP]. It is usually (but not necessarily) used in connection with Netnews articles as defined in [RFC 1036]. The nntp URI takes the form: nntpURI = "nntp" ":" news-server "/" newsgroup-name "/" range news-server = "//" authority range = article-number ["-" [article-number]] article-number = 1*DIGIT C. H. Lindsey [Page 4] The news and nntp URI Schemes May 2005 Observe, in contradistinction to the news scheme, that the is not optional here, because the mapping from to actual articles is established independently by each server. 3.1. The range is a single The resource retrieved by this URI is the Netnews article numbered by the given in the given from the given . 3.2. The range encompasses more than a single The resource retrieved by this URI is some means to gain access to the articles numbered within the given of s in the given from the given (usually by invoking a suitable news reading agent initialized to access that range). A of the form "nnnn-" provides access to all articles numbered "nnnn" and above. 4. Security Considerations There are many security considerations for URI schemes discussed in [RFC 3986]. The news protocol has hitherto used passwords in the clear for authentication, which is considered extremely unsafe in current practice (though [NNTP-AUTH] will eventually rectify that situation). Moreover it offers no privacy (though that is no drawback within the publicly distributed Usenet). 5. Normative References [NNTP] Clive D.W. Feather, "Network News Transport Protocol", draft- ietf-nntpext-base-*.txt. [RFC 1036] M. Horton and R. Adams, "Standard for Interchange of USENET Messages", RFC 1036, December 1987. [RFC 2119] S. Bradner, "Key words for use in RFCs to Indicate Requirement Levels", RFC 2119, March 1997. [RFC 2234] D. Crocker and P. Overell, "Augmented BNF for Syntax Specifications: ABNF", RFC 2234, November 1997. [RFC 3986] T. Berners-Lee, R. Fielding, and L. Masinter, "Uniform Resource Identifier (URI): Generic Syntax", STD 66, January 2005. 6. Informative References [NNTP-AUTH] J. Vinocur, K. Murchison, and C. Newman, "NNTP Extension for Authentication", draft-ietf-nntpext-authinfo-*.txt. C. H. Lindsey [Page 5] The news and nntp URI Schemes May 2005 [RFC 1738] T. Berners-Lee, L. Masinter, and M. McCahill, "Uniform Resource Locators (URL)", RFC 1738, December 1994. [RFC 2822] P. Resnick, "Internet Message Format", RFC 2822, April 2001. [RFC 3987] M. Duerst and M. Suignard, "Internationalized Resource Identifiers (IRIs)", RFC 3987, January 2005. 7. Acknowledgements Thanks are expressed to Paul Hoffman, for his original drafts on this topic, to the members of the uri@w3.org mailing lists (and especially to Frank Ellerman) and to the members of the nntpext Working Group (and especialy to Russ Allbery), who commented on some preliminary versions of this text. 8. Contact Address Charles. H. Lindsey 5 Clerewood Avenue Heald Green Cheadle Cheshire SK8 3JU United Kingdom Phone: +44 161 436 6131 Email: chl@clw.cs.man.ac.uk Comments on this draft should preferably be sent to the mailing list uri@w3.org. Notices 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 BCP 78 and BCP 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 at http://www.ietf.org/ipr. C. H. Lindsey [Page 6] The news and nntp URI Schemes May 2005 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. Full Copyright Statement Copyright (C) The Internet Society (2005). This document is subject to the rights, licenses and restrictions contained in BCP 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 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. C. H. Lindsey [Page 7]