An ID-based cryptographic technique for IFF

A new IFF (identification, friend or foe) scheme is proposed for the Air Defense System. This scheme is based on the modern cryptographic technique, the difficulty of computing a discrete logarithm over a finite field GF(p) with p a prime number. The proposed scheme can be easily implemented and can provide the Air Defense System with a means to achieve aircraft authentication and access control simultaneously without exchanges of coded secret messages through encrypted communications links. The integrity of the air defense protection mechanism can also be enhanced significantly by employing a challenge-response type interrogation protocol.