Real Simple Syndication Kenneth M. Anderson CSCI 7818 November 30, 2000

History Userland Software hosts a website known as Scripting News – In December 1997, this website offered an XML version of its homepage –This XML document was freely available and allowed other web sites to “syndicate” or include scripting news content in their own content Netscape picked up on this idea and introduced my.netscape.com that was based on an XML format known as RSS 0.9 –By July of 1999, the two formats had merged into RSS 0.91 Userland Software produces a Web content-management system known as Manila that allows users to create “Weblogs” that automatically support this format, e.g. users can publish their websites as RSS 0.91 XML documents –This allows other websites to syndicate that content –There are currently thousands of Manila web sites!

RSS, not all fun and games Apparently a minor “war” erupted around this specification in June of 2000 when O’Reilly announced “RSS 1.0” which was developed without the input of Userland Software! –Details from Userland’s point of view are available at: As far as I can tell, Userland has stuck with version 0.91 and is forming a development community that is going to evolve this specification separate from the RSS 1.0 spec!

RSS, the details An RSS document’s root tag is, which has a required “version” attribute. This tag can contain a single element. A channel has several required sub-elements and several optional elements The purpose of the channel tag is to provide (meta) information about some Web content that is available for syndication

Channel, required elements - up to 100 characters, typically the name of a website - a URL to the website, up to 500 chars - a phrase to describe the channel, up to 500 chars - described next - allowable values are listed at:

Channel, required elements continued - provides an image to represent the channel –contains the following required sub-elements - URL of image, 500 chars - describes the image, URL of channel –contains the following optional sub-elements - width of image in pixels, 144 max, 88 default - height of image in pixels, 400 max, 31 default - contents of TITLE attribute for the anchor tag that is generated based on the element above

Channel, optional elements - a copyright notice, 100 chars - editor of the channel, 100 chars, typically an address - technical contact, 100 chars, - a PICS rating, 500 chars - conforms to RFC modification date - pointer (e.g. URL) to RSS spec,, - explained next

Channel, optional elements continued - allows channel to provide access to search or other cgi-provided capabilities in a syndicated context –contains the following sub-elements - label of the Submit button, 100 chars - explains textInput area, e.g. “Search”, 500 chars - name of the text object, 20 chars - URL of cgi script

Channel, optional elements continued - may contain up to seven sub- elements –lists the days in which aggregators must not update their view of the channel –Aggregators are Web “spiders” that travel the web looking for RSS documents. They use the RSS documents to pull information from a channel and “syndicate” it on their host site –unfortunately most aggregators ignore this element

Channel, optional elements continued - may contain up to twenty-four sub-elements –lists the hours in which aggregators must not update their view of the channel –unfortunately most aggregators ignore this element

elements Finally, a channel may contain any number of elements An element has the following sub- elements – - title of story, 100 chars – - URL of the story, 500 chars – - synopsis of the story, 500 chars This is how content of a website is syndicated; each item element syndicates a particular story

An example WriteTheWeb News for web users that write back en-us Copyright 2000, WriteTheWeb team. (continued next slide)

Example, continued WriteTheWeb images/mynetscape88.gif News for web users that write back

Giving the world a pluggable Gnutella WorldOS is a framework on which to build programs that work like Freenet or Gnutella -allowing distributed applications using peer-to-peer routing. Syndication discussions hot up After a period of dormancy, the Syndication mailing list has become active again, with contributions from leaders in traditional media and Web syndication. Example, continued

Rendered Channel An example of a rendered channel is available at: – This shows the latest information in the “WriteTheWeb” channel The above URL pulls information from the WriteTheWeb RSS file to present in its own website; The actual WriteTheWeb web site can be accessed by simply clicking on any of the links contained in the syndicated content