Diffie–Hellman Key Exchange
Traditional secret/single key cryptography uses one key that is shared by both sender and the receiver. But if this key is disclosed, all the communications are compromised. One of the solution to this problem is Diffie-Hellman key exchange. The Diffie-Hellman Key Exchange Protocol is a key agreement protocol that allows authenticated parties to exchange keying material over an unsecured connection. This protocol is widely used in protocols like IPSec and SSL/TLS. Using this protocol, sending and receiving devices in a network derive a secret shared key using which data can be encrypted. To implement Diffie-Hellman, the two end users A and B, while communicating over a channel they know to be private, mutually agree on positive whole numbers p and q , such that p is a prime number and q is a generator of p . The generator q is a number that, when raised to positive whole-number powers less than p , never produces the same result for any two such whole numbers. The v