A way to solve this problem was first proposed by Whitfield Diffie and Martin Hellman. The Diffie-Hellman key agreement protocol uses two sets of mathematically related keys and a complex mathematical equation that takes advantage of this relationship. If each of two computers calculates its own set of related keys (neither set being related to the other) and snares one of the keys with the other computer, they can independently calculate a third secret key that will the same on each computer. This secret key that will be the same on each computer. This secret key can be used independently to generate a number of symmetric encryption keys that the two computers can use to encrypt data traveling from one to the other.