Simple Three Party Key Exchange Protocol via Twin Diffie-Hellman Problem

In 2005, Abdalla and Pointcheval suggested a new variation of the computational DH assumption called chosen based computational Diffie Hellman (CCDH) and presented SPAKE-1 and SPAKE-2 simple password based authenticated key exchange protocols. Since then several three party password authenticated key agreement protocols have been proposed based on CCDH assumption but most of them broken. In this paper, we propose two password based simple three party key exchange protocols via twin Diffie-Hellman problem and show that the proposed protocols provide greater security and efficiency than the existing protocols. The protocols are also verified using Automated Validation of Internet Security Protocols and Applications (AVISPA) which is a push button tool for the automated validation of security protocols and the result shows that they do not have any security flaws.