(per RFC2483) Name : Ron Daniel Jr. E-mail : rdaniel&lanl.gov MIME media type name : Text MIME subtype name : IETF Tree - uri-list Required parameters : none Optional parameters : charset Currently, URIs can be represented using US-ASCII. However, there are many non-standard URIs which use special character sets. Discussion of how to best achieve internationalization of URIs is underway. This registration will be updated with a discussion of the URI charsets once that discussion has concluded. Encoding considerations : Some transfer protocols, such as SMTP, place limits on the length of lines. Very long URIs might exceed those limits. Systems must therefore be prepared to use a suitable content transfer encoding. This is anticipated to be a rare occurance. Security considerations : Client software should be aware of the security considerations of URIs. For example, accessing some URIs can result in sending a death threat to a head of state, frequently prompting a visit from the relevant protective service. Accessing other URIs may result in financial obligations, or access to resources considered inappropriate by one's employer. While the legitimate provider of a uri-list could exploit these properties for good or ill, it is more likely that uri-lists will be falsified in order to exploit such characteristics of URIs. Additionally, the lookup and reverse lookup potential of the uri- list may be attractive to traffic analysts. URI lists may also reveal confidential information, such as the location of sensitive information. Because of these considerations, external confidentiality measures should be available to protect uri-list responses when appropriate. Interoperability considerations : none known Published specification : Uniform Resource Locators (URLs) and Uniform Resource Names (URNs) are two instances of the more general class of identifiers known as Uniform Resource Identifiers (URIs). URN resolution methods frequently wish to return lists of URLs for a resource so that fault-tolerance and load balancing can be achieved. The text/uri-list format is intended to be a very simple format for communicating such lists of URLs (and URNs) in a form suitable for automatic processing. The format of text/uri-list resources is: 1) Any lines beginning with the '#' character are comment lines and are ignored during processing. (Note that URIs may contain the '#' character, so it is only a comment character when it is the first character on a line.) 2) The remaining non-comment lines shall be URIs (URNs or URLs), encoded according to the URL or URN specifications (RFC2141, RFC1738 and RFC2396). Each URI shall appear on one and only one line. Very long URIs are not broken in the text/uri-list format. Content-transfer-encodings may be used to enforce line length limitations. 3) As for all text/* formats, lines are terminated with a CRLF pair. In applications where one URI has been mapped to a list of URIs, the first line of the text/uri-list response SHOULD be a comment giving the original URI. An example of the format is given below: # urn:isbn:0-201-08372-8 http://www.huh.org/books/foo.html http://www.huh.org/books/foo.pdf ftp://ftp.foo.org/books/foo.txt Applications which use this media : URN resolvers are the initial applications. Web clients and proxies are applications that are likely to support this format in the future. Additional information : 1. Magic number(s) : none at this time 2. File extension(s) : .uris or .uri recommended 3. Macintosh file type code : URIs recommended This media type is the product of the URN working group of the IETF. Person to contact for further information : 1. Name : Ron Daniel Jr. 2. E-mail : rdaniel&lanl.gov Intended usage : Limited Use The text/uri-list media type is intended for use in applications which utilize URIs for replicated resources. Author/Change controller : Ron Daniel Jr. Los Alamos National Laboratory rdaniel&lanl.gov