RSS feeds

French | Spanish | Portuguese | Italian | German | Japanese | Chinese | Korean | Russian | Arabic

RSS Feeds and Other “Push” Technologies Emails, Faxes, and Voice Mails Emails, faxes, and voice mails are technologies familiar to many people. However, there are some things that you should be aware of when using these technologies to send information to your team: -  Never send more than one fax per day (or per couple of days). In many cases, it is a waste of resources (like paper), and of the three technologies, faxes tend to be the most irritating when received too frequently. -  Using the information in Article 4, “Communicating with the Team,” design a communication system. Make sure everyone knows if a system has been defined for emails (for example, starting the subject line with “ANN” for announcement or “MTG” for a scheduled meeting), when they should respond to an email or voice mail (upon delivery to indicate that they read it? as soon as they can answer any questions? before the next meeting?), and anything else that has been designed to increase team communication.

-  When leaving a voice mail, keep it short. Provide your name, phone number, reason for your call, and your phone number again. Be sure to say your name and phone number slowly so that the other person can understand it. Newsletters Electronic newsletters let you share information with your team, your company, your customers, and the public. You can use a simpler format and layout for team-only newsletters than those prepared for your company, your customers, or the public. Successful newsletters provide recaps of past work, introduce different team members, provide previews for upcoming products and events, and set expectations. Newsletters can be sent through email or posted on a website.

If you send them through email, they are stored on the recipient’s hard drive until permanently deleted. If team members use the same server for email, then multiple copies will be stored, making a case for posting newsletters to a website. If you post them on a website, you can send an email to announce them (or people can use RSS, discussed next, to find out when the latest newsletter has been posted). RSS RSS is different from the other technologies mentioned earlier. Based on XML, RSS notifies those who want to know (subscribers) when information has changed. This information includes:

-  Pages on a website (including blog entries and wiki pages) -  Headlines, article excerpts, schedules, and so on

-  Weather alerts

-  Announcements (for example, read the latest newsletter, welcome our newest members, and so on) The sidebar shows how RSS works, using blogs as an example. However, the general concepts apply to any updated information: Someone publishes new or changed information; the RSS is created, either manually or automatically; and once the RSS file is finished, it is distributed to syndication servers. In addition, visitors might use an RSS aggregator (sometimes called a “feeder” or “reader”) that searches for updated RSS files on a regular basis.

Visitors choose which RSS feeds they are interested in. For example, Brenda uses Feedreader to keep an eye on the Society of Technical Communication website (http://www.stc.org), Scriptorium’s blog Palimpsest (http://www.scriptorium. com/palimpsest), Darren Barefoot’s blog (http://www.darrenbarefoot.com/), and Rahul Prabhakar’s blog (http://2brahulprabhakar.blogspot. com/), among others. Char uses CITA’s RSS Aggregator to watch many of the same sites Brenda does, plus the STC Forums (http://www.stcforums.org), the MSHelpWiki (http://www.mshelpwiki.com/wiki), and Microsoft Watch (http://www.microsoft-watch.com). We also watch each other’s sites, as well as our own. (If you watch your own site with an aggregator, you know that the RSS file was updated correctly and that your aggregator is working!) Creating and Validating an RSS File Reading this section is only necessary if you want to add an RSS file to your own site, and you are not using an application that automates the process. To manually create an RSS feed, you can use a web-based tool like RSS Creator (http://www.webreference. com/cgi-bin/perl/makerss.pl), or you can use any editor that saves the results as plain text. The file includes information about the site that has been updated and what the update is, using the <item> tag. RSS feed files can contain notices for up to 15 updates. RSS comes in several flavors: -  RSS 0.9x. Originally created by Netscape (when it was known as “Remote Site Syndication”).

The various 0.9x versions have been adapted and enhanced by different companies. -  RSS 1.0. Based on RDF (Resource Description Framework), a universal format for the Web. RDF is a W3C specification and is part of the Semantic Web. -  RSS 2.0. The update to version 0.9x. Now known as “Really Simple Syndication,” this version was released under a Creative Commons license. For more information, see “Web RSS (Syndication) History” at http://goatee.net/2003/rss-history.html. RSS files must contain the following elements:

-  The XML declaration. This tag starts with <?xml version, and identifies the document as XML. It might also include the encoding standard and language. -  <rss> element. Identifies the document as RSS x.x. The version attribute is required. -  <channel> element. This identifies your feed content. -  The tags that make up the feed information, including <title>, <link>, <description>, and <language>. The <lastBuildDate> tag is optional, and identifies the date and time when the RSS feed was changed. The <ttl> tag is also optional, and represents the number of minutes that a feed reader should wait before checking the feed again. -  The tags that identify the feed content, including <item>, <title>, <link>, <guid>, <pubDate>, and <description>. Other optional tags, such as <category>, can also be included. -  Finally, add the closing tags for the feed, including </channel> and </rss>. (Note that all other tags must also be closed when used.) If you create your RSS file, you must validate it or it will not display correctly. The RSS Specifications list several validators at http://www.rss-specifications.com/ feed-validators.htm. For more information on creating RSS feeds, see “RSS Workshop: Publish and Syndicate Your News to the Web” (http://rssgov.com/rssworkshop.html) and “Making an RSS Feed” (http://searchenginewatch.com/ showPage.html?page=2175271).

This page also includes links to other resources, including the RSS Headline Creator (a wizard that takes your information and produces a valid RSS feed). Because there are several versions of RSS (and a lot of forking through the development cycles), a new protocol, called Atom, was developed. Even though it is still in draft form, Atom was published as a proposed standard in RFC 4287 (http://tools.ietf.org/html/rfc4287). Many of the tags in Atom are similar to those in RSS. To learn how to create an Atom feed, see “The Atom Syndication Format” (http://www.atomenabled.org/ developers/syndication/atom-format-spec.php). Using HTML in RSS and Atom Feeds Both RSS and Atom feeds let you include HTML tags in your RSS file to provide formatting and layout. A special tag called “[CDATA]” indicates information that is not parsed (that is, the content is not validated).

[CDATA] lets feed creators pass HTML tags through to the readers. Applying Formatting to RSS and Atom Feeds If you have used HTML tags in your feeds, you can use a cascading style sheet (CSS) to format them. First, you must create the CSS file and save it to your server. Then you must add a second XML tag to the RSS feed to specify the CSS: <?xml-stylesheet type-"text/css" href=http://helpstuff.com/rss.css ?> Alternatively, you can use an XSL stylesheet. (XSL tends to be a bit more complex than CSS.) If you are not familiar with XSL, you can find samples on the web (for example, “Making RSS Pretty” offers sample CSS and XSL files at http://interglacial.com/~sburke/stuff/pretty- rss.html). The XML tag for the XSL is: <?xml-stylesheet type-"text/xsl" href=http://helpstuff.com/rss.xsl ?> Vulnerabilities in RSS Feeds Because RSS feeds can include both HTML and CSS, it is possible to create a malicious RSS feed. RSS aggregator developers have already started dealing with these issues, which is described more fully later in this article. (Aggregators let you accumulate RSS feeds for those sites that you want to track.) Syndicating an RSS Feed If you are using an application that includes RSS feeds, such as blog or wiki software, the updated RSS information is distributed automatically once the content is published.

“Syndication” is how multiple sites share content. People subscribe to the channels that they want to read using an aggregator. Thousands of RSS channels already exist, and some sites publish content to multiple channels (for example, MSNBC offers channels for U.S. news, U.S. politics, world news, business, sports, entertainment, and more). However, if you are manually creating your feeds, use a site like FeedBurner (http://www.feedburner.com) or Technorati (http://www.technorati.com/ping/) to let people know about your content. To make sure that your feed went out correctly, subscribe to it. When you receive the notice, you know that everyone else did, too. To subscribe to feeds, you use a reader or aggregator. Using an RSS Aggregator Many blogs (and other sites) include RSS feed buttons (sometimes labeled “RSS,” sometimes labeled “XML,” and almost always orange or blue). If you click the button, an XML file is displayed in your browser. This XML file contains the latest highlights from the site: headlines, hyperlinks, graphics, metadata, articles, and more. (If you right-click the button, you can add the file to your browser’s articlemark list.) To receive these updates automatically, use an RSS aggregator. The aggregator checks the sites that you are interested in, and lets you know if any of those sites have changed. (It is a lot easier to use the aggregator than to check numerous sites every so often to see if they have changed.) Follow the instructions in your aggregator to add the feeds you want to follow.

Dozens of RSS aggregators exist, and most are free. You can use an RSS aggregator that integrates with a browser, or you can visit websites specifically designed to store your information, or you can install a local application. The choice is yours. For example:

-  Firefox includes “live articlemarks.” If you visit a site that has RSS enabled, a small web feed icon is displayed to the far right of the address field. Click the icon to add the site to your live articlemarks. Other options are Internet Explorer 7, Opera 8, and Safari. To see if the sites have been updated, click the appropriate articlemark icon.

-  Bloglines is a website where you subscribe to blogs, email groups, and websites (after creating an account). You can blog, collect clippings from other blogs, and share your clippings. Everything is organized on a personal web page. Other options are Technorati, FeedBurner, NewsGator (http://www.newsgator.com), and My Yahoo! (http://my.yahoo.com/index.html; requires a Yahoo! account). Websites usually indicate new entries by making them bold.

-  The CITA RSS Aggregator is a Windows application that runs in the background. When any watched feeds are updated, a small window is displayed on the screen (you can choose to read the feed then, read it later, snooze, or ignore the feed). Other options include SharpReader (http://www.sharpreader.net), Feedreader (http://www.feedreader.com), and NetNewsWire (http://www.apple.com/downloads/ macosx/internet- utilities/netnewswire.html). Desktop applications indicate new entries by making them bold or by using icons. Each aggregator type has its pros and cons. Website aggregators like FeedBurner and Technorati mean that you can see the latest news from any computer, but you have to visit the website to see the updates.

Browserbased aggregators let you gather RSS information without installing any applications, but you have to launch a browser and click the articlemarks. Desktop aggregators are installed locally and run in the background, but you cannot use any other computer to access your information. See NewsOnFeeds (newsonfeeds.com/faq/ aggregators) for lists of web-based, desktop, built-in, email, command line, and mobile aggregators. Vulnerabilities with Aggregators While no cases of malicious HTML in RSS feeds have been reported yet, the general consensus is that it is probably just a matter of time. Robert Auger of SPI Dynamics published “Feed Injection in Web 2.0” (available at http://www.spidynamics.com/assets/documents/ HackingFeeds.pdf), which discusses the different types of possible attacks. After the report was published in August 2006, many vendors took notice. James Snell developed a series of tests to check aggregator security (see his blog at http://www.snellspace.com/wp/?p=448). Microsoft’s Internet Explorer 7 developers ran the tests and blogged about it at the Microsoft Team RSS Blog (http://blogs.msdn.com/rssteam/archive/2006/09/09/747111.aspx).

Other developers picked up on this and have tested (and are fixing, as necessary) their aggregators, including FeedDemon’s Nick Bradbury. Steven Garrity of silverorange posted test results on the company blog at http://labs.silverorange.com/archives/ 2003/July/privaterss. Some vendors have already implemented security. For example, the CITA RSS Aggregator strips scripts, ads, and tracking mechanisms, and includes a sample control file that prevents applications from being downloaded. It also encrypts passwords required for restricted RSS feeds. To keep your computer as safe as possible:

-  Request feeds only from sites you trust. -  Disable scripts, applets, and plug-ins. These options can affect functionality.

-  If an “Active Content” warning is displayed, click No so that no applications are installed.

-  Change your security settings to add more restrictions to both the Remote and Local zones. However, it is possible to use so much security that legitimate functionality is impacted. If you request feeds from sites you trust, use a virus checker, and regularly remove spyware, your vulnerability should be limited.