Hazra, Dipanwita2026-11-062026-11-062025http://nits.ndl.gov.in/handle/123456789/280The field of cryptography focuses on securing sensitive information against unauthorized access and cyber threats. One of the most widely used techniques in secure communication is the Diffie-Hellman (DH) key exchange, which enables two parties to establish a shared secret key over a public network. However, DH is susceptible to Man-in-the-Middle (MitM) attacks, where an attacker can intercept or alter the exchanged messages. To mitigate this critical vulnerability, this thesis introduces a novel cryptographic protocol: the Dual RSA-Integrated Diffie Hellman Key Exchange Protocol. The proposed method enhances the standard DH protocol by incorporating two layers of RSA encryption, providing mutual authentication and stronger defense against interception and tampering. The performance and security of the proposed protocol are compared with traditional DH and standalone RSA schemes. Results demonstrate that the integrated approach significantly improves resistance to MitM attacks while maintaining the confidentiality of key exchanges. This makes the Dual RSA-Integrated protocol a more secure and reliable solution for modern encrypted communication systems.enThesis