View Full Version : Mobile Phone Tapping

30-08-2009, 16:59
Well, someone mentioned their concerns about telephone tapping in the thread about Skype being exposed for having a 'back door' to let 'Big Brother' onboard to monitor your conversations etc.

So how about mobile phones; they're safely encrypted - right? :9456:

You might be surprised how weak that encryption actually is if you read the follow article and excerpts I've included in the remainder of the post below - it turns out the code was designed 20 years ago when nobody had powerful enough computers to readily 'break' the code...

Mobile operators pooh-pooh universal phone-snooping plan • The Register (http://www.theregister.co.uk/2009/08/28/mobile_phone_snooping_plan/)

The vast majority of world's cell phone calls are protected by an algorithm known as A5/1 that has been in existence for more than a decade, said project leader Karsten Nohl, a cryptography expert and a researcher at the University of Virginia.

Because it hails from the cold-war era when export laws prohibited the exportation of strong cryptography, the cipher is relatively trivial to break using a large number of networked computers.

More recently, cell phone makers have folded a newer cipher known as A5/3 into handsets to protect internet communications. Because its key is twice as long as A5/1, it's about a quintillion times harder to break, Nohl estimates.

But despite the uncontested superiority of the newer algorithm, handset manufacturers still cling to the older one to protect voice calls.

"This is cold war stuff," Nohl told The Register in explaining why he spearheaded the project, which plans to use a distributed, peer-to-peer computing system to create the table needed to crack A5/1. "I don't see why I should be using something that was intentionally weakened during the cold war."

So you're cellphone ain't all that well protected, surprise, surprise... :gay:

31-08-2009, 10:58
ain't all that well protected, surprise - no, it's known a long time already. :D