Could Net2Phone Sue More Than Skype?

Net2Phone's lawsuit against Skype may ruffle more than just the feathers of the leading VoIP service provider. It could reshape much of the industry. The suit charges that when Skype developed a peer-to-peer architecture it violated Net2Phone's patent, number 6,108,704. The patent describes an architecture where nodes, called processing units, exchange IP addresses to establish peer-to-peer communications.

In some respect this architecture sounds strikingly similar to Skype's overlay peer-to-peer (P2P) architecture. Addresses of online systems are stored in a database on a connection server. A sender queries the connection server to determine whether or not the recipient is online. If so the sender retrieves the IP address from the connection server and establishes a P2P connection with the recipient.

In other respects, though, the Net2Phone design widely diverges from today's architecture. The patent describes a system whereby P2P sessions are established through e-mail. In that instance, senders and receivers swap emails containing their IP addresses with the purposes of establishing a P2P session.

Evaluating any patent infringement case hinges on understanding the specific patent claim that the suit contends was infringed upon, says J. Matthew Buchanan, patent attorney at Dunlap, Codding, and Rogers. In this case, evaluating those claims at this stage is difficult because Net2Phone, a division of IDT, is first asking for full disclosure from Skype before naming specific claim violations.

Until the specific claims are disclosed its difficult to know thye likelyhood of Net2Phone's success against Skype. What may be easier to ascertain, however, is whether Net2Phone could pursue even bigger fish -- the rest of the VoIP industry. Most VoIP protocols use P2P connections of some kind. SIP certainly does. SIP also uses a location server, like a connection server, as defined in patent 6,108,704.If so could Net2Phone sue any vendor in the SIP community? We'll bring in a panel of experts to try and answer that question later this week.