INDIVIDUAL PROBLEMS: Discrete log, Diffie-Hellman, Massey-Omura DUE 1/22/01

 8.  Assue you know that 7amod 31 = 10.  What is a?

 9.  Two individuals decide to use the Diffie-Hellman Key Exchange System to communicate a key.  They agree that p=11 and s=8.  One chooses private key 3 (a=3) and the other private key 4 (b=4).  Verify that they each wind up with the same key.

10.  One individual wants to send a message consisting of the single number 25 to another using the Massey-Omura System.  Both agree on the prime p=31.  The sender chooses two private keys:  13 and 7;  the receiver chooses two private keys:  17 and 23.  Verify that the receiver actually receives the number 25.