There's been a lot of talk lately about Skype and the possibility that it has changed its network architecture in part to give law enforcement authorities the ability to listen in on Skype calls. At first, a spokesperson for Skype would not comment on these claims, but now we have a bit more information.
Now, in a long and detailed post on the official Skype blog, its Chief Development and Operations Officer Mark Gillett had denied these claims. He does confirm that Skype has ditched its previous peer-to-peer network of client-hosted supernodes in favor of cloud-based servers hosted by Skype. However, he said that these plans were in place long before Skype was acquired by Microsoft in 2011.
Early this year we completed our move of all of our supernodes into Microsoft's global data-center footprint so we and our users can benefit from the network connectivity and support that powers Microsoft's other global scale cloud software including Xbox Live, Bing, SkyDrive, Hotmail and Office 365. This provides a real benefit to our users and to our ability to continue to scale the Skype product.
Gillett also said that this new network structure "does not provide for monitoring or recording of calls." He also denied that the changes would allow law enforcement authorities a way to access Skype generated instant messages. He added:
As I have outlined above, if a law enforcement entity follows the appropriate procedures and we are asked to access messages stored temporarily on our servers, we will do so. I must reiterate we will do so only if legally required and technically feasible.
All Skype to Skype calls are still encrypted, according to Gillett, with the exception of the Skype client released for the Chinese market, which has a chat filter in place in order to comply with the country's laws.
Source: Skype blog