Abstract: Due to the high computational overhead of group key agreement protocol in wireless sensor network(WSN),this paper presented a pairing-free certificateless group key agreement protocol.During system initialization phase,the partial private key is generated by key generation center of the certificateless public key cryptography.Each node gene-rates private key via multiplying secret value by corresponding partial private key.During node authentication phase,this protocol introduces node authentication mechanism based on scalar multiplication of elliptic curves,determining the nodes identity information by calculating scalar multiplication of partial private key and temporary public key with authentication information.During session key generation phase,session key is generated by utilizing scalar multiplication to reduce the computational overhead.Finally,we analyzed computational overhead and communication cost.The results show that this protocol can not only ensure security of node communication,but also reduce computational overhead.

Key words: Wireless sensor network,Group key agreement,Pairing-free,Certificateless