Governmental bodies, such as military and national security agencies, keep looking for proprietary encryption algorithms to secure their confidential communication applications. Customizing published encryption algorithms is a trend to acquire proprietary encryption algorithms at affordable research and development cost. Cost, here, may be represented by the required efforts for designing and testing the customized algorithm. The security architecture of the 3rd Generation Partnership Project (3GPP) mobile communications includes a standardized encryption algorithm F8 which is based on the...