Improvised Diffie Hellman Key Exchange Protocol

Abstract

Protecting exchange of data over an insecure network is very crucial to maintain confidentiality. Diffie- Hellman protocol is a fundamental key exchange method and has proved to be a secure mechanism to securely exchange the cryptographic keys. Ralph Markel developed this idea, which has got its name from Whitfield Diffie and Martin Hellman. In this protocol, the recipient and transmitter generate a standard secret key and then start talking to each other over the open channel known to all. Diffie – Hellman secures a set of internet facilities. The transmitter has to confide in the public key cryptosystem while obtaining the recipient's public key and contrariwise and this happens to be a drawback of public key cryptosystem. The current DH algorithm is quite prone to man–in–the–middle attack which is a kind of cyber eavesdropping. The eavesdropper is present in the public channel in MITM attack, the eavesdropper receives both the transmitter and recipient's public key, and sends public keys to the transmitter and recipient that are created by him. This is how MITM takes place in this algorithm. Another attack that is very likely on this algorithm is service denial attack. In this type of attack, the attacker tries to prevent the contact between transmitter and recipient and he may do so either by deleting the messages or miscommunicating both the parties. Many other attacks on this algorithm are possible, such as Outsider attack, Insider attack, etc. We have improvised this algorithm to a next level to reduce the probability of attacks on it. In this paper, we have proposed an upgraded DH algorithm by making use of the notion of the existing DH algorithm to generate a more secure secret key, which is then swapped between the transmitter and the recipient so that a new shared secret key can be created for each message. Obtaining the first secret key’s primitive root would produce the second secret key.