Efficient three-party password-based key exchange scheme

In three-party password-based key exchange protocol, a client is allowed to share a human-memorable password with a trusted server such that two clients can negotiate a session key to communicate with each other secretly. Recently, many three-party password-based key exchange protocols have been developed. However, these proposed schemes cannot simultaneously achieve security and efficiency. Based on elliptic curve cryptography (ECC), this paper will propose a new simple three-party password-based authenticated key exchange scheme. The proposed method not only reduces computation cost for remote users and a trusted server but also is more efficient than previously proposed schemes. It is better suited for resource constrained devices, such as smart cards or mobile units.