A New Type of Cipher: DICING_csb

In this paper, we will propose a new type of cipher named DICING_csb, which is derived from our previous stream cipher DICING. It has applied a stream of subkey and an encryption form of block ciphers, so it may be viewed as a combinative of stream cipher and block cipher. Hence, the new type of cipher has fast rate like a stream cipher and need no MAC.Comment: There is a new variant added in the section

Stream cipher based on quasigroup string transformations in Zp∗Z_p^*

In this paper we design a stream cipher that uses the algebraic structure of the multiplicative group \bbbz_p^* (where p is a big prime number used in ElGamal algorithm), by defining a quasigroup of order $p-1$ and by doing quasigroup string transformations. The cryptographical strength of the proposed stream cipher is based on the fact that breaking it would be at least as hard as solving systems of multivariate polynomial equations modulo big prime number $p$ which is NP-hard problem and there are no known fast randomized or deterministic algorithms for solving it. Unlikely the speed of known ciphers that work in \bbbz_p^* for big prime numbers $p$, the speed of this stream cipher both in encryption and decryption phase is comparable with the fastest symmetric-key stream ciphers.Comment: Small revisions and added reference

A novel H.264 SVC encryption scheme for secure bit-rate transcoding

This paper presents a novel architecture for the secure delivery of encrypted H.264 SVC bitstreams. It relies on a block cipher and stream cipher used in a novel way that would allow an intermediary transcoder to truncate the bitstream to the appropriate bit-rate without decrypting the data. The system, called SVC-sec, is compared to other architectures presented in the literature and it is shown that SVC-sec offers many benefits, particularly when used with FGS streams.This paper presents a novel architecture for the secure delivery of encrypted H.264 SVC bitstreams. It relies on a block cipher and stream cipher used in a novel way that would allow an intermediary transcoder to truncate the bitstream to the appropriate bit-rate without decrypting the data. The system, called SVC-sec, is compared to other architectures presented in the literature and it is shown that SVC-sec offers many benefits, particularly when used with FGS stream

A New Guess-and-Determine Attack on the A5/1 Stream Cipher

In Europe and North America, the most widely used stream cipher to ensure privacy and confidentiality of conversations in GSM mobile phones is the A5/1. In this paper, we present a new attack on the A5/1 stream cipher with an average time complexity of 2^(48.5), which is much less than the brute-force attack with a complexity of 2^(64). The attack has a 100% success rate and requires about 5.65GB storage. We provide a detailed description of our new attack along with its implementation and results.Comment: 14 pages, 4 figures, 3 table