Skype Encryption

Skype is a popular communication tool allowing people to have voice and video conversations over the internet. And one of its features is how it transports that communications data. Skype first encrypts your data then distributes it using a network of other skype users (using what’s called a peer to peer model).

The encryption is intended to stop random strangers eavesdropping on your conversations. And it seems to be fairly effective from what this article says – the German Federal Police Office have a problem wiretapping Skype calls.

Is this a good thing or a bad thing? Well, it’s a little of both. It gives Skype users a level of security that makes the general public comfortable enough to use it, and stops casual eavesdropping. That’s the good news.

The bad news is that VoIP traffic (phone calls over internet) can be intercepted in other ways. When it becomes too hard to break the encryption, as the German police found, an easier path is to install a trojan on the PC and intercept the voice data before it becomes encrypted. This stuff really happens.

The German federal police office is looking into developing trojans so they can install one on people’s computers they need to listen in on (article here). This is a legal form of spyware (at least in the country it’s used in). Other governments have been using this technique for years and legally it’s not much different to wiretapping a phone. What makes it scary is that antivirus companies have an understanding with law enforcement agencies and some government spyware may go undetected.

This isn’t a problem to most people. And at the end of the day it’s no different to using a house or mobile (cellular) phone.

The message in this article is that you should place the same level of trust in any VoIP phone (such as Skype) as you would with any other phone. It doesn’t offer any additional level of privacy. Law enforcement agencies have been finding ways to listen in, and fairly soon we’ll have spyware that can do the same thing only with less legal intentions.