Hybrid encryption algorithm based improved RSA and diffie-hellman

Internet and Network applications have seen a tremendous growth in the last decade. As a result incidents of cyber attacks and compromised security are increasing. This requires more focus on strengthening and securing our communication. One way to achieve this is cryptography. Although a lot of work has been done in this area but this problem still has scope of improvement. In this paper we have focused on asymmetric key cryptography. In asymmetric key cryptography, also called Public Key cryptography, two different keys (which form a key pair) are used. One key is used for encryption & only the other corresponding key must be used for decryption. No other key can decrypt the message, not even the original (i.e. the first) key used for encryption. The beauty of this scheme is that every communicating party needs just a key pair for communicating with any number of other communicating parties. Once someone obtains a key pair, he/she can communicate with anyone else. RSA is a well known public key cryptography algorithm. It is the first algorithm known to be suitable for signing as well as encryption, and was one of the first great advances in public key cryptography. The security of the RSA cryptosystem is based on two mathematical problems: the problem of factoring large numbers know mathematical attack and the problem of trying all possible private keys know brute force attack. So to improve the security, this scheme presents a new cryptography algorithm based on novel method by combining the two most popular algorithms RSA as Improved RSA (IRSA) and Diffie-Hellman in order to achieve more security.