PHILADELPHIA -- New software developed by Ipsum Networks, a start-up co-founded by a University of Pennsylvania engineering professor, has shown promise in detecting hard-to-spot bottlenecks in computer networks, winning $6 million in new venture funding.

The first version of this software, known as Route Dynamics, is now available to companies and other users that transmit data via decentralized Internet Protocol networks.

IP networks have gained popularity because they don't rely on a central computer and are therefore more resistant to attacks and failure, but this complex architecture also makes them much harder to monitor and repair,said Roch Guerin, professor of electrical and systems engineering at Penn and CEO of Ipsum. Managing an IP network is now a labor-intensive art rather than an automated science. Making matters worse, corporations can lose literally millions of dollars for every second their IP network is down.

IP networks work by dividing data into packets, which are addressed and then transmitted by way of a series of routers. A router detects a packet ultimate address and communicates with other routers before sending the packet to another machine that it believes is closer to the packet final destination.

Route Dynamics monitors communications between routers as well as communications between entire networks, a level of surveillance not attainable with existing programs, which measure only network speed or simply monitor devices. The new software may help assuage corporationsconcerns about moving business-critical functions onto IP networks.

Ultimately, an IP network is only as good as the communication between its routers,said Guerin, who founded Ipsum with onetime IBM colleague Raju Rajan, now Ipsum chief technology officer. When routers share inaccurate information, it can slow or freeze a network; such performance difficulties are generally the first sign of trouble. But ideally you like to catch the problem before network performance is compromised.

Because it nearly impossible even for skilled network administrators to spot less-than-optimal communication between routers, such problems can take a significant amount of time and money to solve. Performance sometimes suffers for extended periods as computer professionals attempt to identify the problem, making organizations increasingly interested in automating monitoring of IP networks.

In addition to monitoring existing networks, Route Dynamics can also predict the performance of a network. If a user wants to determine how an added piece of equipment will affect a network performance, Route Dynamics can perform simulations.

Ipsum new funding comes from New York-based Rho Ventures, in conjunction with Sevin Rosen of Dallas and Palo Alto, Calif. Sevin Rosen also provided Ipsum with initial funding of $1.5 million in 2001.