Law says government needs a court order to monitor or record calls. Pen register used to determine the number called. Nature and scope of information government can collect changed. Cryptography making and breaking secret codes. The art and science of hiding data in plain sight.
Coded text is called ciphertext .
Until recently both sender and recipient must know key. Generally key must be transmitted by more difficult method for security. Public key cryptograph eliminates need for secure transmission of keys. The New Controversies 1991 statement in Senate bill said . Did not pass 1992 launched series of bills digital telephony bills or wiretap bills requiring technology used in comm be redesigned and existing equip.