Fault Resistant Trivium-like Stream Cipher Using Higher Radii Cellular Automata
Anita John, Sai Kallupalle Mineesh Reddy and Jimmy Jose
In this era of cutting edge technology, the need for designing efficient and compact stream ciphers has gained much importance. Trivium, one of the eSTREAM project finalists, was designed to be used in hardware-constrained devices. The use of shift registers in the cipher made it susceptible to cryptanalytic attacks. In recent years, Cellular Automata (CA) have evolved as a good cryptographic primitive in the design of stream ciphers. CA are also considered as a good alternative for shift registers in the design of stream ciphers. This paper proposes a new Trivium-like stream cipher called Pentavium which uses 5- neighbourhood CA instead of shift registers of Trivium. The new cipher has a very fast initialization phase when compared to Trivium since it reduces the number of initialization cycles from 1152 to 32 without any compromise to the cryptographic properties of the cipher. The use of higher radii CA in the design makes it resistant to the attacks that were prevalent on reduced rounds of Trivium. The paper also discusses the hardware implementation of the cipher and compares it with Trivium and its variant CAvium.
Keywords: Stream cipher, cellular automata, trivium, 5-neighbourhood CA, fault attacks, cellular automata based stream cipher, pentavium