Cryptographers have moved closer to their goal of eavesdropping on cellphone
conversations after cracking the secret code used to prevent the interception of
radio signals as they travel between handsets and mobile operators' base
stations.
At a hacker conference in Berlin that runs through Wednesday, the
cryptographers said they've cracked the algorithm that determines the random
channel hopping and have devised a practical means to capture entire calls using
equipment that costs about $4,000. At the heart of the crack is open-source
software for computer-controlled radios that makes the frequency changes at
precisely the same time, and in the same order, that the cellphone and base
station do.
