Kangaroo A Proposed Stream Cipher Algorithm

Abstract

Stream cipher designers offer new algorithms by employing thecharacteristics of the basic structure to get algorithms that have advanced featuresfrom security and speed stand point of view. Taking into consideration the benefitfrom the scientific and technical development at the publish time of theiralgorithms versions. This research proposes the design of a new efficient andsecure stream cipher, named (Kangaroo) which was designed to be more securethan conventional stream cipher systems that use XOR for mixing. The proposedalgorithm encompasses two major components. The first part involves the PseudoRandom Number Generator (PRNG) using Rabbit algorithm. And the second partinvolves a nonlinear invertible round function (combiner) to perform theencryption and decryption processes. This will lead to strengthen the weak XORcombiner. The proposed cipher is not a random number generator alone. Instead itis self-synchronizing stream cipher such that - the cipher text influences its internalfunctioning. The proposed algorithm uses 16-bytes secret key to encrypt theplaintext which is multiple of 16-bytes up to (264 bytes) length. Also theperformance and memory requirements of the proposed system are evaluated. Suchthat the setup stage requires 1987 operations and the encryption/decryptionprocesses require 4 operations per byte. And the memory requirement is 344 bytes.The implementation was done on a (Pentium IV, 1.79 GHz, 224 MB of RAM) PC,Windows XP, using (Java Builder 7).