Secure Session Key Sharing Using Public Key Cryptography

In distributed systems, entities perform the predefined tasks distributively and have to communicate quite frequently. Confidentiality is the primary security requirement in such systems. There should be some secure mechanism whereby a pair of entities can securely communicate with each other. In most of the applications of distributed systems, computational and communication resources are limited and any such mechanism that ensures security of data under transmission should consider these computational and communicational constraints. Symmetric key cryptography emerges as one of the effective mechanisms to secure the data in distributed systems. The security of a symmetric key mechanism purely depends on the secrecy of the session key. In this paper, we have proposed a protocol for the sharing of session key between communicating entities securely. The proposed protocol secures the session through asymmetric key mechanism and once the session key is securely shared, the entities can communicate through the shared session key.