Geospatial data sharing comes of age on Web

Humans like to structure their information by geography.

“I overhear a lot of cell phone conversations, and the first thing that people say is where they are,” says Mark DeMulder, director of the National Center for Geospatial Intelligence Standards, an office within the National Geospatial-Intelligence Agency. “The military and intelligence community are no different. We want to understand the world based on the location of people and things.”

When NGA last month publicly released its new baseline standards for ensuring interoperability among geospatial data sets, it marked society’s imposition of order on the physical world, in data terms, through the formal convergence of four technologies that have been increasingly interwoven over the past decade.

Global Positioning Systems, geographic information systems and remote sensing devices started coming together in the 1990s, DeMulder said. But over the past five to seven years, it was the addition of the Internet—with its ability to enable sharing of data—that led to the drive for defining standards.

“We recognize a fundamental shift in the way we do business [and] what we’re doing to take advantage of that shift,” DeMulder said.

The geospatial information community is vast. It comprises the 16 federal intelligence agencies—including the Defense, Energy, Homeland Security, State and Treasury departments, and law enforcement agencies such as the FBI—and numerous organizations such as the Geological Survey within civilian agencies. State and county government agencies that compile geospatial information, and foreign countries such as coalition partners, are also included.

“Just about every state has a GIS coordinator,” and there are 3,300 counties in the United States alone, DeMulder said.

Such a wide-ranging group represents diverse interests, making it imperative that standards be developed for entering, processing, and transmitting data, as well as dealing with architectural issues such as identifying a common structure for metadata, DeMulder said.

The standards center is part of the NGA Office of the Chief Architect. NCGIS participated in crafting the new standards, but it also undertakes compliance testing to make sure that “interoperability” is a reality, not just a buzzword.

“It’s a growth area for us—we’re expanding the amount and scope of our standards testing,” he said.

Because the Internet has created untold opportunities for collaboration and sharing, most of the new standards deal with Web-enabled data, such as specifications for Web Feature Service, Geography Markup Language, Web Map Service and Styled Layer Descriptors.

But the new standards do not yet define the geospatial information universe, DeMulder said.

“The baseline connotation [means] this is the minimum we need for our service-oriented architecture,” he said. “There is one in the wings, a family of standards related to the portrayal of symbology, map symbols. … We’re standardizing on graphic representations so that someone from DHS and someone from NGA and a state emergency response person, if they’re looking at the same information, they can instantly recognize it.”

DeMulder said he expected the symbology standard to be released within the next 12 months.