Iowa State University

Inside Iowa State
Feb. 21, 1997

Patrolling the net

by Anita Rollins
Doug Jacobson may have help for school officials who are anxious about letting their students "travel" electronically without a tour guide.

The associate professor of electrical and computer engineering developed a management tool, ScreenDoor, that permits easy control of the sites children are allowed to visit when they use the Internet.

Developed with funding from the Center for Advanced Technology Development, the technology serves as a type of Internet surveillance system. Just as a screen door permits air movement but can be locked to keep individuals out or in, Jacobson's technology allows Internet discourse but can block access to pre-selected sites.

With customized PC-based hardware and software, ScreenDoor watches the traffic on the network, observing source and destination information. Based on guidelines set by the individual controlling the system, ScreenDoor looks for inappropriate connections. When the device finds one, it sends information to both the source and destination machines, indicating that the connection is being terminated.

Jacobson said the technology is not like systems currently on the market.

Those systems, typically used by large companies, are expensive - in the $10,000 range - and are designed to protect company computers from outside access, according to Jacobson. Another option is local software, which is less expensive ($10 to $50 per machine) but must be installed and managed on a computer-by-computer basis, he said.

"Neither of these options is really appropriate for schools," explained Jacobson. "Teachers or administrators want to manage a whole bank of computers, make changes quickly and monitor both internal and external access. This technology permits that type of use, at a reasonable cost."

Jacobson said it is nearly impossible to find ways around ScreenDoor's surveillance system - in fact, it is difficult to know when it is present.

The technology will be sold through Jacobson's new company, MidAmerica Networking Inc. (soon to be Palisade Systems Inc.), located at the ISU Research Park. Stephanie Bridges, a former student of Jacobson's, is the company president.

MidAmerica expects to have a product available for sale in March.

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