A secure and efficient conference scheme for mobile communications

A growing application area in mobile communications is mobile teleconferencing, in which a group of mobile users collaborate in an interactive procedure, such as a board meeting, a task force, a scientific discussion, or even a virtual classroom. Wireless communications transmit conversations via radio, making them more susceptible to eavesdropping and unauthorized access than are conversations carried via wires. Therefore, it is crucial to ensure confidentiality and authenticity in mobile teleconferencing. When deploying secure services in mobile teleconferences, it has to be taken into account that the mobility of users is usually built on portable devices with limited computing capability. A secure conference scheme for mobile communications needs to be executed efficiently on portable devices. We propose a new secure and efficient conference scheme for mobile communications. Based on a modular square root technique, this scheme is secure against eavesdropping, impersonating, and tracking attacks and allows a participant to join or quit a mobile teleconference dynamically. In addition, the scheme is particularly efficient on the mobile user's portable device because the mobile user needs to perform only single modular multiplication plus encryptions and decryptions of a secret key cryptosystem.