Secure data transfer in MANET using symmetric and asymmetric cryptography

MANET is ad-hoc network in which mobile nodes co-operatively route the traffic to the nodes which are beyond their direct range. The mobile nodes are free to join or leave the network at will. The open architecture and dynamic topology coupled with lack of infrastructure make MANET vulnerable to variety of attacks at all layers. The secure transmission of data over MANET is a critical requirement. In this paper we have proposed a technique which provides secure transmission of data. The technique involves encryption of data using symmetric cryptographic technique, and also generating the digital signature of the data using the asymmetric cryptographic technique from the Hash of the data. The encrypted data is transmitted through the network to the destination where the received data and digital signature of the data are validated using symmetric and asymmetric cryptography. The data on validation is accepted thus ensuring secure data transmission. The proposed technique provides confidentiality, integrity, authenticity and non-repudiation to the data. It protects the data transmitted over the network from snooping, modification, replay and fabrication attack at the application layer.