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XML and CDF: GCA's XML Conference Web Site

Elmhurst

Dianne Kennedy
CEO / Chief Consultant, XMLXperts Ltd. / GCA

146 NorthEnd Avenue
Elmhurst (Illinois) (USA) 60126
Email: kennedy@xmlxperts.com

Biographical notice

Dianne Kennedy is an independent Publishing Systems Consultant. As a consultant, Ms. Kennedy delivers SGML/XML tutorials and offers document engineering and publishing system design consulting services.

Ms. Kennedy has been an active participant in many industry SGML standards activities. Currently she serves as chairperson for the DTD Working Group of SAE J2008 for the automotive industry. She is also convener WG6 for ISO 12083, the SGML standard for the coding of articles and books.

Dianne Kennedy has worked with the Graphics Communication Association since 1984 to introduce SGML and now XML to the publishing community through the GCA Information Technologies Tutorial Series. She currently serves as a program consultant to GCA, is editor of GCA's XML Files Magazine, and is executive director of GCA's Independent Consultants Cooperative.

CDF

Channel Definition Format
channels

Introduction

One of the first working applications of XML is a vocabulary, or tag set, known as "Channel Definition Format," or CDF. In fact, CDF was implemented as part of Microsoft's Internet Explorer 4.0 in late 1997 and today many of us have experience using channels (implemented using CDF) on the Web. The word channel may appear in many different contexts. We are all used to the concept of a channel on television. Channels provide us with an organization of content, usually offered by a single provider (ABC, CBS, FOX, NBC) or by content classification. We have the sports channel, the learning channel and even shopping channels. And we know that we have access to some channels but not to others. Usually access is based upon the level of service to which we have subscribed with our cable or satellite provider. On the Web, a channel serves a very similar function.

Organizing content into channels on the Web is challenging. We could organize information on our web site by directories and link pages in those directories through navigation devices (such as navigation bars) inserted into each individual page. If the Web site is simple, this is easy and relatively straightforward. But if the Web site is complex and updated frequently, management of the Web site becomes a challenge. And we must always keep in mind that in order for our Web site to be useful; the navigation of the site must be straightforward and easy for visitors to the site to use as well.

XML has brought us another approach to creating Web sites by creating channels. This approach requires that we describe the content and structure of the site explicitly so that it is accessible. The description (metadata) should provide both people and software agents with information about the collection of Web pages. The information needs to be available for a variety of services including browsers, indexers, and other agents by using a common format (XML) for describing channels of information. This is the role of "Channel Definition Format."

pull
push

More about CDF

Channel Definition Format is an XML tag set that can be used to describe channel information. It was developed by Microsoft and today is supported in Microsoft browsers and a host of other software including RIO from Datachannel. Channels can be used on the Web to deliver information that you want (or subscribe to). Typically you must search the Web to find information and then "pull" it into your browser. But when content is delivered to you using channels it is said to have been "pushed" to your browser. Information can be pushed to you based on your individual user profile or a group profile. The CDF tag set enables push technology.

A minimal CDF file contains the CHANNEL tag and a pointer (href) to an HTML page, along with the title and an abstract for the page. The title and abstract will be used to help visitors to the Web site navigate to the information they want. Below is a simple tag set:

<?XML Version="1.0"?>
             <CHANNEL HREF="http://www.x-act.org/xml98/xmlindex.htm" >
             <TITLE>XML '98</TITLE>
             <ABSTRACT>Web site for XML '98 Conference</ABSTRACT>
             </CHANNEL>

CDF also gives us the ability to arrange pages within the channels. This is done by creating an "ITEM" within a channel. Either ITEM or CHANNEL can require a login in order for users to access information. This enables us to provide different content to each user based on user profile or group profile.

<?XML version "1.0"?>
<CHANNEL href="http://www.x-act.org/xml98/index.htm">
<TITLE>XML '98</TITLE>
<ABSTRACT>This is the XML/CDF Version of GCA's XML '98 Web site!</ABSTRACT>

<ITEM href="http://www.x-act.org/xml98/hotel.htm">
<TITLE>Hotel Information</TITLE>
<ABSTRACT>About the Conference Hotel</ABSTRACT>
</ITEM>

<ITEM href="http://www.x-act.org/xml98/peer.htm">
<TITLE>Peer Reviewer Instructions </TITLE>
<ABSTRACT>Contains instructions and access to papers for those doing the peer review.</ABSTRACT>
<LOGIN/>
</ITEM> . . . 
</CHANNEL>

CDF tags can be hand-coded for your Web pages, but Datachannel's RIO technology takes care of automating the creation CDF metadata for your Web site and stores pages for you as well. RIO is a database-driven application that enables you to specify user profiles, group profiles, and content organization. RIO exports this information as CDF out of the database for your use. The CDF output can be used with channel features in browsers to provide site navigation and security access for your Web pages.

GCA, Graphic Communication Association

OASIS

X-ACT.org

GCA's XML Web Site

GCA, the Graphic Communications Association, and host for the XML '98 Conference, has fostered SGML from day one. GCA is committed to being the XML Association as well. So it is critical that GCA employ XML on a day-to-day basis. In keeping with this mission, GCA sponsored the development of an XML Web site to manage the XML '98 Conference. This Web site, linked to the "official" GCA site, was used to manage paper submissions and peer review, conference scheduling, as well as to serve as a way to distribute conference information to the general public. X-ACT.org, a member organization of OASIS (Organization for the Advancement of Structured Information Standards), provided the demonstration technology as well as host server in Bellevue, Washington.

The first step in creating the CDF version of the conference Web site was to decide upon channels and who should have access to each channel. Sunny Lauritzen (X-ACT.org / Datachannel) and Dianne Kennedy (GCA/XMLXperts Ltd.) were designated as system administrators. As such, Sunny and Dianne had the ability to create channels, publish to channels, create user logins, create group profiles, and grant access to the contents of a channel. Staff (including GCA staff and the conference co-chairs) was placed in a group which had access to the entire conference site. Each person was given a login that placed them in the staff group and gave them access to all channels. Peer reviewers were also given special logins. Peer reviewers were given access to conference information channels as well as to the channels where paper submissions were posted for review. Peer reviewers did not have access to other conference management channels such as scheduling or conference call notes.

It is important to note that some users experienced some difficulty due to differences in browser technology. Those with older Web browsers could see the channels, but had difficulty accessing the Java-based login scripts. Several staff members had to upgrade their browser technology in order to become CDF enabled. In addition, those with America Online experienced some difficulties. In order to access the login scripts, AOL users had to connect to the Web, then launch a browser other than the default AOL browser in order to login.

The Peer Review Process

As papers were submitted for XML '98, each paper was reviewed by Dianne Kennedy, assigned a track, and posted to the Web in that track channel as an HTML file. The RIO technology enables files to be "saved to the Web" in literally any format. But because reviewers had different client-side software configurations, HTML was selected as the most usable format for the review of paper submissions. New papers were posted on a daily basis. Peer reviewers simply had to go the Web site, log in, and they could then gain access to the papers for review. New papers that had been posted were highlighted for reviewers, so they could quickly find the newest additions to the tracks. Reviews were sent to GCA via email. However, with a bit of instruction, it would have been possible for reviewers to post their reviews directly to the Web for staff to read there.

Using channel technology GCA was able to facilitate peer review and the final selection and coordination of conference papers. Prior to using XML, paper submission and peer review were done manually and took far greater effort.

Conference Information

GCA uses its Web site to distribute information about its upcoming conferences. For XML '98 two Web sites were prepared. The first was a traditional HTML-only Web site. Initially this site suffered because navigation was difficult. The site was re-designed to include a navigation bar that listed topics and provided links to these topics. Construction of a new version the navigation bar was required for each of the Web pages that were linked on the site. So, for example, on the page listing hotel information, the bar had to contain links to all the other pages (Tutorials, Tracks, Registration, At a Glance, and Conference Info). And on the page for tutorials, the bar had to contain slightly different links (Tracks, Registration, At a Glance, Conference Info, and Hotel Information). Not only was constructing the unique bar for each page (and testing the links) time consuming, but as content was added to the Web site, the navigation bar had to be updated on each page to provide new links. Not an ideal situation!

Following the selection of papers and printing the full conference brochure, the XML / CDF Web site was created. This version of the Web site used Version 3.0 of RIO. Because XML and CDF provide automatic site navigation by channel, there was no requirement to create special navigation bars to link each Web page with other pages of interest. In fact, navigation bars were deleted from each existing Web page altogether. And best of all, new channels and pages could be added without having to edit other pages to create new links. The new pages simply fit within the channel hierarchy and were reflected in the channel navigation interface. This alone saved time and effort, as well as to provide better navigation for the visitor to the site.

Summary

Like all experiences with a new technology, the GCA XML Web site experienced some fits and starts. However, all factors considered, the XML-enabled Web site provided great behind-the-scenes benefit to conference staff. In addition, it gave a clear demonstration that development of content for a Conference Web was streamlined and the navigation provided to the end user was far superior. GCA looks forward to using CDF for management of its upcoming XML conference in March 1999, Xtech '99, in San Jose.


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