## Cryptology ePrint Archive: Report 2007/114

High Efficiency Feedback Shift Register: $\sigma-$LFSR

Guang Zeng and Wenbao Han and Kaicheng He

Abstract: We introduce a new kind of word-oriented linear feedback shift register called $\sigma-$LFSR which is constructed with the instructions of the modern processor and have fast software implementation. We offer an algorithm to search for good primitive $\sigma-$LFSR. In particular, we give two examples HHZ-1 and HHZ-2 and compare their efficiency and security with those of the LFSRs appearing in stream ciphers such as SNOW, SOBER and Turing. Our results show that replacing the LFSRs in SNOW, SOBER and Turing with HHZ-1 will improve security and the efficiency of fast software implementation.

Category / Keywords: secret-key cryptography / stream ciphers