ABC is a synchronous stream cipher optimized for software applications. Its key length is 128 bits. It accommodates a 128-bit initial vector. Here a version of ABC with a 128-bit key and 32-bit internal variables is presented. A new approach to the design of stream ciphers has been used which results in a cipher based upon keyand clock-dependent state transition and filter functions. More preci...

Cryptanalysis of a cryptographic function like stream, block or hash function usually requires human cryptanalytical skills and labour. However, some automation is possible – e.g., by randomness testing suites like NIST/Diehard that can be applied to test statistical properties of cryptographic function outputs. Yet such testing suites are limited only to predefined statistical functions. We pr...

Recent articles [6, 3, 5, 7] introduce the concept of phase shifting equivalent keys in stream ciphers, and exploit this concept in order to mount attacks on some specific ciphers. The idea behind phase shifting equivalent keys is that, for many ciphers, each internal state can be considered as the result of an injection of a key and initialization vector. This enables speeding up the standard ...

Performance in hardware has been demonstrated to be an important factor in the evaluation of candidates for cryptographic standards. Up to now, no consensus exists on how such an evaluation should be performed in order to make it fair, transparent, practical, and acceptable for the majority of the cryptographic community. In this report, we formulate a proposal for a fair and comprehensive eval...