Date Added: Mar 2013
This paper gives a new proposed cryptosystem (REBC3) that is designed to take advantages of the new generation of 64bits microprocessors which commercially known as x64 systems. The old version REBC2, which was published in Africon 2007. REBC2 was basically developed for the 32bits microprocessors which are commercially known as x86 systems. REBC3 like REBC2 use the concept of rotor enhanced block cipher which was initially proposed by the author in [NRSC 2002] on the first version of REBC. REBC2 used the same concept from a another point of view, which is using rotors to achieve two basic cryptographic operations; permutation, and substitution.