In Mobile Ad hoc Network (MANET), to resolve the crisis in message confidentiality and authenticity , new hybrid  algorithm is proposed based on Elliptic curve cryptography .Generally MANET‟s are vulnerable to attacks because of their open environment ,where all nodes are involved in the data transfer .To improve the performance in MANETs and to protect it from various attacks we propose a highly secured cryptographic protocol .This scheme aims to incorporate the best features of both digital signature and encryption schemes in a single step. Elliptic curve method is significantly efficient  with reduced key size, and it is highly infeasible against Brute force attacks when compared with Advanced Encryption standard methods .As the key size is reduced which in turn curtails the memory constraints which is very much important in a resource constrained environment .  The proposed work will help nodes to avoid vulnerable assaults within themselves and also aims to increase the performance of MANETs by averting malicious nodes. In this paper, Elliptic Curve cryptography is applied for data encryption. It also provides reliable and efficient transmission of data in a MANET, which will drastically reduce intruders within and outside the network.  

Keywords: Elliptic curve cryptography; Hybrid Signcryption ; Warm Hole attack; Grey Hole Attack; Denial of service attack; Authentication, Packet Delivery ratio, Distributed routing.