Network in a Full View

YOU MIGHT HAVE seen the poster that at first glance looks like either a view through a microscope or a time-release photo of a festive fireworks display. On closer inspection, of course, you'd see this is a map of the Internet, which dis-plays all of the routers in existence organized by their IP numbers.

The first map was made in 1998 at Bell Labs, shortly before Lumeta, which owns the mapping technology, spun off from Bell. Since then, Lumeta has been improving its IPsonar technology and producing a new map of the Internet every year or so since.

The company's IPsonar 4.1 brings the power of the Internet Mapping Project to your own little corner of the Internet -- your network. It will detect all the devices in a specified range of IP numbers, and let you see what you have and how they relate to one another, and can identify if you have a leak.

IPsonar gathers information about network devices in four phases of discovery. During Network Discovery in our test-ing, the program identified the devices in the network and how they were interconnected. It paid particular attention to forwarding and filtering devices, in addition to the connectivity of network firewalls and router access control lists.

The second task was Host Discovery, in which the program conducted a search of all the IP addresses. IPsonar uses multiprotocol discovery to find previously unknown IP addresses, which always seem prevalent on larger networks.

The third phase, Leak Discovery, is probably the most useful for any network administrator concerned with data security. In this phase, IPsonar scanned our various hosts to see if they could accept inbound or send outbound packets to the Internet or other sub-networks. Even devices that are on a secure network but can exchange information with another device on a nonsecure network would be suspect.

You can set the number of links in the chain you want the program to check. Leaks are discovered using an external leak sensor -- Lumeta maintains...