In an encryption system comprising DES in a cipher feedback mode of k bits, a plain text bit stream is fed into n individual DES encryptors. The DES encryptor operates in parallel from a common input register containing cipher text bit streams so that the overall throughput of the system is increased...http://www.google.ca/patents/US4731843?utm_source=gb-gplus-sharePatent US4731843 - Method and device of increasing the execution speed of cipher feedback mode of the DES by an arbitrary multiplier
