... part of the Web Site of George North

... from ... The Washington Post "on line"

Tuesday, January 30, 2003: Page E01

The Semantic Web

By Leslie Walker
Washington Post Staff Writer

Tim Berners-Lee could well be the J.R.R. Tolkien of the computer world.

Tolkien, a philologist and author of "The Lord of the Rings," created a fantasy world in which characters used languages he invented. Berners-Lee is the inventor who gave us the World Wide Web, a system built on "languages" largely created by Berners-Lee. He's now working on a sequel, called the Semantic Web.

"It is a paradigm shift, like the original World Wide Web," Berners-Lee told scientists gathered at the National Science Foundation to hear his progress report Monday.

Recalling how hard it was for people to understand what the Web was when he crafted it in 1989, Berners-Lee said he's having difficulty again explaining the Semantic Web, for the same reason: "There's this mental leap involved."

The 47-year-old software engineer is spearheading the futuristic project as part of his role as director of the Web's global standards-setting body, the World Wide Web Consortium, based at the Massachusetts Institute of Technology. He has been working on it for more than four years, throughout both the dot-com boom he helped trigger and the bust that came afterward.

Skeptics see the Semantic Web as little more than a Utopian vision nurtured in academia; they privately pooh-pooh it as the "Pedantic Web." Some doubt it will take root in the real world, where commercial interests are bent on colonizing the Web and have embarked on a drive to reshape the Internet on their own terms. For the most part, corporate America hasn't bought into Berners-Lee's vision.

Yet much as Tolkien's world sprang up like magic from his "Elvish" languages, Berners-Lee created special alchemy when he wrote HTTP, HTML, URLs and those other computer protocols with funny acronyms to form the original Web. Now he seems determined to make magic strike twice.

The somber-faced visionary peppered his talk with a fresh batch of acronyms representing the building blocks for the Semantic Web. There's OWL (for Web ontology language), RDF (resource descriptor framework), URI (uniform resource identifier) and DAML (Darpa agency mark-up language). Out of this strange alphabet soup Berners-Lee sees a more powerful Web emerging, one where documents and data will be annotated with special codes allowing computers to search and analyze the Web automatically.

The codes go to the heart of the Semantic Web. They are designed to add meaning to the global network in ways that make sense to computers, not humans. This machine-readable intelligence would come from hyperlinked vocabularies that Web authors would use to explicitly define their words and concepts as they post their stuff online. The idea is the codes would let software "agents" analyze the Web on our behalf, making smart inferences that go far beyond the simple linguistic analyses performed by today's search engines. Some even think the Semantic Web will be able to "think" like humans, but Berners-Lee made no such grand claims.

He sketched a scenario in which 350 people fell ill with a mysterious disease. Tapping into the Semantic Web, a scientist hunts for clues to its origin. "Is it an allergy? Is it something in the atmosphere? Is it a virus? We don't know, but you want to correlate about everything you've got," Berners-Lee theorized.

In his futuristic scenario, the Semantic Web offers controlled access to American health care data, plus databases charting the location and status of rivers, underground water, forests and local vegetation, along with economic data on local industries and what they produce -- all marked up in special vocabularies. Those allow scientists to run global queries across the Web, fishing randomly for correlations that might exist between where the sick people lived, worked and played -- such as a polluted stream or industrial dump. Even more fanciful, Berners-Lee described all sorts of analytical tools the scientist could use, tools that might replace our aging Web browsers, letting us display data by color codes, by geographic maps or by types of sources searched.

All of which presumes that people will annotate their Web data in advance using URI, RDF and OWL codes. At this point, the code-creation process still isn't finished. There's ongoing debate, too, about the logic and rules that will govern the complex syntax, including what privacy rules should govern access to the data. The World Wide Web Consortium is attempting to set these standards, leading a collaborative effort among scientists around the world.

Questioned about whether the Semantic Web could collide or be superseded by a parallel effort by leading software vendors to create business automation software known as "Web services," Berners-Lee said he hoped the two would become interoperable after they're finished. Web services are about "remote operations," he explained, meaning they provide a way for disparate computers and devices running different software to communicate over the Internet. The Semantic Web, he said, is more about "expressing things in data and making the data reusable."

"But in general they are very different angles of computing," he insisted. "It's not as if they are competing for the same turf."

Yet proponents of both often talk about how they'll help automate the same tedious tasks online, such as researching travel itineraries and pricing data from various sources. Berners-Lee said he used Semantic Web syntax to write a software program that pulls down all his financial statements from his bank's Web site and then automatically spits out a completed tax return for him at the end of the year. Software vendors often describe similar scenarios using Web services.

International Business Machines has been at the forefront of the Web services movement, so I checked in with IBM the day after the speech for a commercial take on the Semantic Web. Bob Suter, IBM's director of Web services, said he viewed the Semantic Web as an "adventurous research project" with noble goals, though he expressed skepticism that enough people would embrace its elaborate mark-up requirements to make it useful.

"The fundamental problem is people are going to be lazy about adding all this extra information to their Web pages," Suter said.

For now, there doesn't seem to be much momentum behind the Semantic Web, but I wouldn't bet against the man who invented the World Wide Web. After all, he saw something no one else did back in 1989. Listening to him describe what the future could hold if everyone agreed to use common Web vocabularies makes me think he sees something special once again.

And if he pulls it off, the limelight-shy inventor could remake cyberspace all over again.

Leslie Walker's e-mail address is walkerl@washpost.com.