Skype ist zwar auf der einen Seite möglicherweise recht sicher, da die Gespräche verschlüsselt übers Netz gehen (solange sie im IP-Netz bleiben und nicht ins Festnetz vermittelt werden). Doch es gibt zwei Mankos: Skye weigert sich, das Verschlüsselungsverfahren offenzulegen. Das spricht nicht gerade für einen starken Kryptmechanismus. Und andererseits?
Yahoo Finance über die Zusammenarbeit zwischen Skype und den US Behörden:
Kurt Sauer, Skype’s chief security officer, said there are no „back doors“ that could let a government bypass the encryption on a call. At the same time, he said Skype „cooperates fully with all lawful requests from relevant authorities.“ He would not give particulars on the type of support provided.
The U.S. Justice Department did not respond to questions about its views on Skype’s encryption.
Verso’s Bannerman notes that Skype calls are decrypted if they enter the traditional telephone network to communicate with regular phones, so a conversation could be intercepted there. Skype does not reveal how many of its calls run on the phone network.
„There are other ways of getting at the conversation than brute-force decryption of the hacking,“ Bannerman said.
Schneier believes that eavesdropping on the content of calls is not as important to the NSA as tracking the calls, which is still possible with Skype. For instance, if a particular account were associated with a terrorist or criminal, it would be possible to identify his conversation partners.
„What you and I are saying is much less important than the fact that you and I are talking,“ Schneier says. „Against traffic analysis, encryption is irrelevant.“