Abstract: Wireless sensor networks consist of autonomous sensor nodes attached to one or more base stations. Security is critical for many sensor network applications. Traditional key management techniques, such as public key cryptography or key distribution center (e.g., Kerberos), are often not effective for wireless sensor networks for the serious limitations in terms of computational power, energy supply, network bandwidth and defection of center authority. In order to balance the security and efficiency using group key agreement protocol and also support dynamic operations like join, leave, merge, etc. by using ECC based Diffie Hellman key exchange. This protocol employs ternary tree like structure instead of binary tree in the process of group key generation.

Keywords: ECC, group key agreement, ternary tree, ECC based Diffie-Hellman.