IE7 and Longhorn to Get RSS Support
Microsoft IE7 and Windows Longhorn to Get RSS Support
By Greg DeMichillie [bio]
Posted: Jul. 18, 2005
* Chart: The Long and Winding Road of RSS
* Illustration: RSS in Action
* Sidebar: RSS Extensions and Creative Commons
The following is the full text of an article published by Directions on Microsoft, an independent research firm focused exclusively on Microsoft strategy & technology. Each month we make one or more key articles available to non-subscribers.
* See more samples
* See a list of upcoming articles and reports
The next versions of Internet Explorer (IE) and Windows (code-named Longhorn) will support RSS, an XML format for syndicating news and other Web content such as Web logs ("blogs"), enabling users to subscribe to a site and be notified when new content has been posted. But details remain sketchy on which of the proposed features are part of Longhorn and which are part of IE 7.0, and will therefore be available on Windows XP SP2 as well. Furthermore, multiple incompatible versions of RSS are available, and its future is clouded by infighting between the major players.
RSS: Not Just for Blogs
RSS is not a single standard or format—RSS developers can't even agree on what the letters "RSS" stand for. Rather, it is an umbrella term for a set of XML formats for syndicating news and other newslike Web sites. A site that uses RSS publishes on its site an XML file that summarizes its contents (often referred to as an "RSS feed.") When new content is posted to the Web site, the feed is also updated, usually with the assistance of an application built for that purpose. A user subscribes to the feed using an RSS-aware client application (often called an "aggregator," because it aggregates feeds from all of the user's subscribed sites.) The aggregator will periodically download a new version of the RSS file and notify the user of any new content that has been published.
Although RSS is best known for its use on blogs (many of whose owners tirelessly promote its benefits), many other types of Web sites offer RSS feeds, including major news organizations, such as the New York Times, CNN, and the BBC; online special interest sites, such as the popular Digital Photography Review, which uses RSS to inform readers of new product reviews; and Microsoft, which makes its security bulletins available to IT professionals via an RSS feed (although no Microsoft software currently supports RSS). Some sites, such as most blogs, choose to include the complete text of their content in the RSS feed while others, most notably subscription-based sites and those that rely on advertising, include only a summary of the content and require users to navigate back to the site to read the full contents.
Microsoft and other advocates of RSS expect it to play a larger role in the future and become a common way for users to receive many kinds of information—even information that doesn't come from a Web site. A corporate enterprise resource planning (ERP) application, for example, might produce an RSS feed with sales information updated on a daily basis, in addition to offering such information through traditional reporting technologies or via e-mail.
Simple Idea, Complicated History
Although the idea behind RSS is simple, it has suffered from a checkered development history that has hampered its adoption. As a result of this history, there are two similar but incompatible formats based on different underlying technologies, both attempting to solve the same problem in similar ways, and both using the name RSS.
The most recent versions of each of these parallel tracks are as follows:
RSS 1.0 is based on the Resource Description Framework (RDF), an XML format originally developed by Netscape to help third-party Web sites plug in to the My Netscape portal, and it has more advanced capabilities, such as having an author field for each item in a feed.
RSS 2.0, developed by blogger Dave Winer, is based on neither RSS 1.0 nor RDF, and is designed to be easier for developers to read and write.
(For details on the history of the term "RSS" and versions of RSS in use, see the chart "The Long and Winding Road of RSS".)
Both RSS specifications are ambiguous and do not fully describe what an RSS aggregator is expected to do when it encounters certain tags. For example, some aggregators allow the use of HTML markup tags, such as indicating bold-faced characters, within the title of an RSS entry and will display the title appropriately, while others will just display the text of the tag rather than applying the desired style. This leads to RSS feeds appearing differently when viewed by different aggregators.
Because of these differences, a group of programmers led by Sam Ruby (a member of IBM's Emerging Technologies Group and a key contributor to many Web services standards) is trying to craft a third alternative, known as Atom, that addresses the needs of both RSS camps and is rigorously specified.
Big Plans for RSS
IE 7 will support current and past versions of RSS (and Atom) in several ways. First, it will try to automatically discover if a Web site has an associated feed by looking for a link on the page that follows any of several techniques commonly used by Web publishers to indicate an RSS feed. Once a user has subscribed to a feed, IE will automatically display how many unread entries the feed contains.
(Similar features are already available in other browsers, such as Firefox on Windows and the Mac and Safari on the Mac. For an illustration of how RSS subscriptions work in those browsers, see "RSS in Action".)
Microsoft also plans to add RSS capabilities to the core Windows client OS. Plans for the Longhorn client call for it to support RSS and Atom through two major components that will manage the download of feeds and provide an API for applications to retrieve the data.
The Common RSS Store will hold the list of feeds to which the user has subscribed and will give application developers an API for adding and removing feeds and accessing content from feeds. A systemwide list of RSS feeds will allow multiple applications to access data from any of the user's feeds. A user could subscribe to a blog via IE, for example, and have any audio content published by that blog appear in Windows Media Player and any calendar entries appear in Outlook.
The Platform Sync Engine will download new content as it becomes available and place the content, including enclosures, into the Common Store. Providing a system-level component that downloads RSS content removes one of the limitations of current RSS applications—the fact that new content is only downloaded while an RSS-enabled application is running.
Finally, in addition to adding RSS to its own products, Microsoft is proposing a set of extensions to RSS that will make it more suitable for Web sites whose information is not strictly chronological. RSS assumes that content is always ordered from newest to oldest, but some sites might want a different ordering. An online bookseller, for example, might want to publish an RSS feed of its top sellers, ordered by sales volume. Microsoft is making these extensions available under flexible licensing terms that give third parties rights to not only use the technology but to also make derivate works. (For details on the licensing terms, see the sidebar "RSS Extensions and Creative Commons".)
Details Sketchy Until Sept. 2005 PDC
Although its announcement of RSS support was greeted with generally positive reaction from the blogging community, many questions won't be answered until Microsoft's Sept. 2005 Professional Developers Conference (PDC). Open questions include the following:
How much RSS support will be available on Windows XP SP2? Microsoft has not made clear which of the demonstrated RSS features are part of IE and will therefore be available on Windows XP SP2 and Longhorn, and which will only be available in Longhorn. Beyond resolving technical issues, Microsoft faces a marketing dilemma: making features unique to Longhorn raises the value of Longhorn to customers, but makes it less likely that ISVs will build applications that rely on those features, because many more PCs will be using Windows XP in the next two or three years than using Longhorn. On the other hand, making features available on Windows XP as well as Longhorn makes it easier for ISVs but lessens the value of a new OS to customers.
What other Microsoft applications will support RSS? Although it's clear that IE will support RSS, some of the scenarios Microsoft envisions will require RSS support in applications such as the Windows Media Player and Outlook.
Will Microsoft's server products generate RSS? Thus far, all of Microsoft's demonstrations and announcements have been about client-side support for RSS. But in order for RSS to be useful, Web sites and other applications must generate RSS feeds. Corporate developers, in particular, will be looking for Microsoft to support RSS in server products such as SQL Server and ASP.NET (which would extend such support to Windows SharePoint Services and SharePoint Portal Server.)
What kind of tools support will be available? The proposed Common RSS Store will provide an API for applications to retrieve data from RSS feeds. Developers will want to know whether this new API is built around the .NET Framework or is a traditional Windows-style API, and what kind of tools support will be available.
Resources
Specifications for RSS 1.0, RSS 2.0, and Atom are available at web.resource.org/rss/1.0, blogs.law.harvard.edu/tech/rss, and www.ietf.org/html.charters/atompub-charter.html, respectively.
The Longhorn RSS team blog is at blogs.msdn.com/rssteam.
Microsoft's proposed RSS extensions are described at msdn.microsoft.com/longhorn/understanding/rss/simplefeedextensions.
A summary of the Creative Commons Attribution-ShareAlike license and the full legal text is at creativecommons.org/licenses/by-sa/2.0/ and creativecommons.org/licenses/by-sa/2.0/legalcode.
A book published by O'Reilly, Developing Feeds with RSS and Atom (ISBN 0-596-00881-3), gives developers specific guidelines on authoring feeds using a variety of tools and languages.
August 6, 2005 at 01:44 PM in Browsers | Permalink
| TrackBack (12)
| Top of page
| Blog Home
