Long description

The figure shows the exchange of message between Alice and Bob and also the transmission and interception of a ciphered message between Alice, Bob, and Eve, which are the fictional characters shown here as the placeholders in Diffie - Hellman Key exchange.

The exchange of messages between Alice and Bob is shown as follows:

Alice performs some calculations where “a” equals 3 and the value of b is unknown. g superscript b mod p equals 5. Open parenthesis g superscript b close parenthesis superscript “a” baseline equals open parenthesis 5 close parenthesis superscript raised to the third power mod p equals 4.

Alice sends a message to Bob as follows: g superscript “a” mod p equals 8.

Bob performs some calculation where the value of “a” is unknown and b equals 4. g superscript “a” mod p equals 8. Open parenthesis g superscript “a” close parenthesis superscript b baseline equals open parenthesis 8 close parenthesis superscript raised to the fourth power mod p equals 4.

Bob responds to Alice as follows: g superscript b baseline mod p equals 5.

On the other hand, A file is ciphered with the key that reads, open parenthesis g superscript b close parenthesis superscript “a”. The ciphered file is intercepted by Eve. Eve performs some calculations where g equals 2 and p equals 11. g superscript b mod p equals 5. g superscript “a” mod p equals 8. The value of open parenthesis g superscript b close parenthesis superscript “a” is unknown. The value of “a” and b are also unknown. The ciphered file is then deciphered at its destination using the key that reads, open parenthesis g superscript b close parenthesis superscript “a”.