| 摘要 |
An encryption procedure for the transfer of data as characters from a sending to a receiving unit. An encrypted base key (BK) is produced in the sending unit, where after a modified base key (MBK) is formed through the combination of the initial base key (BK) with a random number (RND) issued by the receiving unit and is then transmitted encrypted to the receiving unit.By encrypting the random number (RND) in the modified base key (MBK), the first number of bits of a keystream (KS) is produced. A number (x) is then added before each subsequent encryption so that subsequent bits of the keystream (KS) are the same size.In transformation process 1 (TP 1), the data to be transferred is then converted by character following control information retrieved from the keystream (KS). In transformation process 2 (TP 2), the transferred information undergoes a similar reverse conversion at the receiving unit. This conversion is controlled by a keystream (KS) formed here for restoring the transferred data to text form.<IMAGE> |
