"This has not changed the underlying nature of Skype's peer-to-peer architecture, in which supernodes simply allow users to find one another. Calls do not pass through supernodes," Mark Gillett, chief development and operations officer, said in an email.

"We believe this approach has immediate performance, scalability and availability benefits for the hundreds of millions of users that make up the Skype community," he said.

Because Skype has not rerouted voice, video and messaging traffic through supernodes, nothing substantive has changed in its network in regards to privacy. "As was true before the Microsoft acquisition," a Skype representative said in a separate email.

Skype, like all other U.S. telecoms providing real-time communications, is required to provide law enforcement with access to its network. Under federal law, police with warrants can eavesdrop on conversations. Skype encrypts voice, video and data traffic and holds the decryption keys.

Skype's peer-to-peer network is much cheaper to use than making international calls on traditional carriers' networks. While the overall service quality is lower, it is good enough for people calling friends and family. Skype is free between registered users.