Slid Pairs in the Initialisation of the A5/1 Stream Cipher
نویسندگان
چکیده
A5/1 is a shift register based stream cipher which uses a majority clocking rule to update its registers. It is designed to provide privacy for the GSM system. In this paper, we analyse the initialisation process of A5/1. We demonstrate a sliding property of the A5/1 cipher, where every valid internal state is also a legitimate loaded state and multiple key-IV pairs produce phase shifted keystream sequences. We describe a possible ciphertext only attack based on this property. keywords: A5/1, initialisation process, resynchronisation, slide attacks, stream cipher.
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Weak key-IV Pairs in the A5/1 Stream Cipher
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