Qualys Inc this week released a free Web-based network-management tool that lets users scan and map any network connected to the Internet.

The program, called FreeMap, is accessed through Qualys' Web site. When users register on the site and enter a Web domain or IP address to map, the system E-mails them a link, which then must be visited to begin the scan. Upon completion, the program presents a graphical map of the chosen network, as well as the results of a vulnerability scan identifying possible security holes.

The service will help businesses increase the security of their networks, because they'll be able to make free, frequent, external scans, Qualys CEO Phillipe Coutot says. And the system is superior to existing network-discovery tools such as Nmap, he argues, in part since it's delivered as a Web service. "The beauty is, you don't need people to deploy the application," he says.

Since the program is available to any Web user with a valid E-mail address (not including free, anonymous services like Hotmail or Yahoo!) it's likely some folks with malicious intent will attempt to use it to find vulnerabilities they can exploit. But IT managers shouldn't be afraid of having some light shed on their networks, according to Mark Iovinelli, manager of the design and implementation team for commercial printing giant R.R. Donnelly. "If you've done your due diligence, a port scan is no threat to you anymore," he says. "If you have your firewalls, there's nothing they can see."

R.R. Donnelly subscribes to Qualys' paid services, and Iovinelli says having a tool that can scan your network for vulnerabilities is essential, adding that, "You have to measure your network before you can better it."