In contrast to these attacks, our attack which is based on the work by Keller and Seitz [KS01] is running on an existing special-purpose hardware device, called COPACOBANA. With the knowledge of only 64 bits of keystream the machine is able to reveal the corresponding internal 64-bit state of the cipher in about 7 hours on average. Besides providing a detailed description of our attack architecture as well as implementation results, we propose and analyze an optimization that leads again to an improvement of about 16% in computation time.
Category / Keywords: A5/1, GSM, special-purpose hardware, COPACOBANA Date: received 31 Mar 2008 Contact author: arupp at crypto rub de Available format(s): PDF | BibTeX Citation Version: 20080401:022941 (All versions of this report) Short URL: ia.cr/2008/147