A new quantum authentication and key distribution protocol

Abstract

Key distribution is a fundamental problem in cryptography, in both symmetric and asymmetric ciphers. Symmetric ciphers usually resort to a courier-based method for key exchange, as do quantum key distribution systems. On the other hand, a schema for using hash functions as a medium for key exchange in both symmetric and asymmetric cipher was proposed by several investigators. However, if the schema is to be successful, the channel utilized should be substantially authenticated. Furthermore, and quite recently, the advancement in quantum-based communications has provided better means for authentication, which is utilized in this work. This thesis builds a novel key distribution protocol, based on cascaded hash functions, utilizing a communication channel that is authenticated based on the quantum-authentication by a deterministic six-state protocol (6DP). The basic idea is to divide this key distribution protocol into two processes; the control process where the 6DP is utilized to authenticate the channel, and the second process where cascaded hash functions, based on key distribution techniques, are used to construct the key at the sender and receiver sites. The hardware built for quantum authentication process is a field programmable gate array (FPGA) at the sender site, to control the setting of the quantum states through a random generator built into the FPGA. In addition, the FPGA is used to synchronize the laser timing pulses and opening/closing of the detectors gates to prevent eavesdroppers from compromising the security, hence authentication is established.