Chapel Hill Computational Linguists Crack Skype Calls

mikejuk writes "You might think of linguistics as being interesting but not really useful. Now computational linguistics [PDF of original paper] has been used to crack Skype encryption and reconstruct what is being said in a VoIP call. What is surprising is that though they are encrypted, the frames that make up a Skype call contain clues about what phonemes are being spoken."

Re:Side channel attack

[Anonymous Coward]

The simple description is: By looking at the size of the encrypted data packets you can guess what phonemes were spoken. Yes, that's all there is to it. They are just looking at how much data is sent and guessing what might be said that reasonably fits in that size.

An obvious simple fix would be to vary the length of the packets with random padding (using a cryptographically secure random algorithm to determine the length). It would add overhead but probably not that much considering how small these packets are in the first place (they typically don't use the full allotted bandwidth).

Fsck You, Slashdot

[theshibboleth]

"You might think of linguistics as being interesting but not really useful" Way to go Slashdot, insult one of the most important fields in existence. Do the editors and readers really not realize how closely comp ling is related to AI? I have confidence that eventually computational linguistics will crack speech/language in general and lead to computers that can learn languages as readily as human infants. This will be momentous because it would allow communication between computers and humans. Now it wouldn't solve the consciousness problem, but it would be a step in the right direction.

Re:Side channel attack

[thePowerOfGrayskull]

There's a reason that SSH has inserted random padding into its packets since its inception. You would think that the folks at Skype might've done just a a bit more research...