INTERNET-DRAFT L. Masinter, J. Gettys, B. Carpenter draft-masinter-url-ipv6-01 Expires six months after publication date September 1, 1998 Using IPv6 Addresses in URLs 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). Copyright Notice Copyright (C) The Internet Society (1997). All Rights Reserved. Abstract The normal textual representation for IPv6 addresses as a set of colon-separated hexadecimal numbers does not work well with most deployed URL-parsing software. This document describes an alternate format which will pass unharmed through most URL-parsing software. 1. Introduction The normal textual representation for IPv6 addresses as a set of colon-separated hexadecimal numbers does not work well with most deployed URL-parsing software. This document describes an alternate format which will pass unharmed through most URL-parsing software. 2. Background The standard representation for IPv6 addresses in text is defined in section 2.2 of [RFC2373] ("Text Representation of Addresses"). This representation uses hexadecimal values separated by colon ":", double colon "::", and optionally ending period-separated decimal values for the four low-order 8-bit pieces of the address. Unfortunately, using this IPv6 syntax within URLs [RFC2396] would be disruptive for many applications. Within the "hostport" section of the generic URI syntax, the colon is used to separate the host name or address from an (optional) port number. Thus, in some addresses, a colon followed by a decimal number could ambiguously be interpreted as a port designator or as a part of the IPv6 address. Even if there were no ambiguity, this syntax is incompatible with a many deployed applications that parse (but do not resolve) URLs, including many CGI scripts, robots, search engines, and so forth. 3. Syntax This specification defines a simple, safe representation for IPv6 addresses within URLs, by defining a syntax which will look like a domain name to otherwise unaware software. The syntax is best described as a transformation of the normal IPv6 syntax as defined in section 2.2 of [RFC2373]; starting with such an address: 1) replace every colon ":" with a "-" 2) append ".ipv6" to the end Thus, an HTTP service available at port 70 of IPv6 address "ABCD:EF01::2345:10.9.8.7" could be written as http://ABCD-EF01--2345-10.9.8.7.ipv6:70/ This syntax should always be used. Internet software that resolves host names and addresses in URLs should be modified to recognize the "ipv6" pseudo-domain. 4. IANA considerations The Internet Assigned Names Authority is requested to reserve the "ipv6" pseudo-domain for the purpose outlined in this memo. 5. References [RFC2396] R. Fielding, L. Masinter, T. Berners-Lee, "Uniform Resource Identifiers: Generic Syntax", August, 1998. [RFC2373] R. Hinden, S. Deering. "IP Version 6 Addressing Architecture", July, 1998. 6. Authors' Addresses Larry Masinter Xerox Palo Alto Research Center 3333 Coyote Hill Road Palo Alto, CA 94034, USA Fax: +1 650 812 4365 EMail: firstname.lastname@example.org James Gettys MIT Laboratory for Computer Science 545 Technology Square Cambridge, MA 02139, USA Fax: +1 617 258 8682 Email: email@example.com Brian Carpenter IBM United Kingdom Laboratories MP 185, Hursley Park Winchester, Hampshire SO21 2JN, UK Email: firstname.lastname@example.org 7. Full Copyright Statement Copyright (C) The Internet Society (1997). All Rights Reserved. This document and translations of it may be copied and furnished to others, and derivative works that comment on or otherwise explain it or assist in its implementation may be prepared, copied, published and distributed, in whole or in part, without restriction of any kind, provided that the above copyright notice and this paragraph are included on all such copies and derivative works. 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