Skype protocol cracked?

If the blog posting is correct, software developers who currently don't have access to Skype's protocol could develop and sell alternative Skype clients. This could prove problematic for eBay, which has kept the protocol private since acquiring Skype last year.

Charlie Paglee

In a statement, a Skype representative acknowledged but dismissed the claim.

"We have no evidence to suggest that this is true," the representative said. "Even if it was possible to do this, the software code would lack the feature set and reliability of Skype, which is enjoyed by over 100 million users today. Moreover, no amount of reverse engineering would threaten Skype's cryptographic security or integrity."

Charlie Paglee, chief executive of Vozin Communications, a company that sells a voice over Internet Protocol (VoIP) plug-in called Talqer, first reported the claim on his VoIPWiki Blog. Talqer enables Google Talk users to make phone calls from their PCs to regular phones.

Paglee detailed a conversation he had with the Chinese engineers about the reverse-engineered VoIP technology. He said he was able to verify that they were using the Skype protocol, but he said the quality of the call was not as good as calls made using the actual Skype service.

After about 10 minutes, he said, the call was actually dropped. Paglee would not identify the company that allegedly cracked the Skype protocol; he said the start-up is still operating in stealth mode.

"Right now, it's still not quite there," he said. "But they've only been working on this for about eight months. I expect in a couple of weeks, they will have something working that has a lot better quality than what they showed me."

While Skype publishes application-specific interfaces, or APIs, for developers who want to provide add-on applications for the Skype service, it has kept its protocol that allows the actual Skype client software to communicate with other Skype clients a secret.

Because Skype's protocol is proprietary, third-party developers are not able to develop applications that align closely with the client software. Other VoIP applications, including Google Talk, have opened their protocol to the public, allowing companies like Vozin to develop service add-ons that are specific to the software client.

Paglee said the Chinese start-up plans to license its reverse-engineered protocol to third-party developers, which will be able to embed it in software used to build Skype-compatible applications. For example, Vozin could use the protocol to build a plug-in that would allow Skype users to make calls to and accept calls from regular phones without buying the PC-to-phone service from Skype.

Paglee said the effect on Skype could be devastating.

"It's safe to say that Skype is more popular than any other VoIP provider," he said. "And if this Chinese company could open the protocol and license it to other companies, and developers come up with applications that are better than Skype's, then they can really take revenue away from Skype."