Method and apparatus for forming unique user identification data at remote terminal for secure transmission of data from host terminal

摘要

The present invention relates to a method and apparatus to determine whether a user is authorized to utilize a data communication network, and more particularly a terminal machine in the network. Data having a predetermined number of bits are read out from a relatively large random number memory, containing previously stored data, by using key data to address said bits at the terminal machine. The addressed data are used as new key data and data each having a predetermined number of bits are repeatedly read from the data in the random number memory to form identification data on the basis of the old and new key data in each cycle. In such manner, there are formed identification data unequivocally determined in accordance with the key data and having high security or confidentiality.