Patent ID: 7673151

Claim:
A processor that performs an encryption/decryption operation, the processor comprising: a control device that receives at least one initial key, the control device comprising: a memory that temporarily stores the at least one initial key, and at least one external key input that receives the at least one initial key from a source; a round key generator connected to the control device via at least one communication device, wherein the round key generator receives the at least one initial key from the control device to calculate at least one round key and transfers the at least one round key to the memory of the control device; at least one encryption/decryption device comprising: at least one external data input that receives external data, an input that receives the at least one round key from the memory of the control device, and at least one external data output that outputs the external data encrypted or decrypted with the at least one round key by the at least one encryption/decryption device, wherein the at least one encryption/decryption device and the round key generator communicate solely via the control device, and the control device transmits intermediate results to the round key generator to perform recursive calculation of the at least one round key; a first request line that sends requests from the at least one encryption/decryption device to the control device; and a second request line that sends requests from the round key generator to the control device, wherein the at least one encryption/decryption device and the round key generator both transmit requests on the respective first and second request lines to start the encryption/decryption operation after both requests are met, wherein the encryption/decryption operation is repeated as often as necessary, except for receiving the at least one initial key by the control device, to encrypt or decrypt a set of external data.