International Journal of Scientific and Research Publications, Volume 5, Issue 1, January 2015 1 ISSN 2250-3153 www.ijsrp.org Single Wavelength Entangled Pair in Quantum Channel Authentication for QKD Mohamed Youssef Khalaf Elwadeya * , Khalid S. A. Al-Khateeb ** , Nurul Fadzlin Hasbullah ** * Department of Electrical and Computer Engineering, International Islamic University Malaysia ** Department of Electrical and Computer Engineering, International Islamic University Malaysia *** Department of Electrical and Computer Engineering, International Islamic University Malaysia Abstract- The photon splitting of an UV into entangled pair of different wavelengths using non-linear crystals is a complicated procedure in the quantum authentication process (QAP) as presented in the six states deterministic protocol (6DP). A simplified process is proposed; the photon splitting process is replaced with basic polarization splitting of a single wavelength in the visible range. The quantum states are prepared, as usual, using retardation wave-plates. The transmitting station sends to the receiver a sequence of random polarized pulses via a quantum channel. The receiver blindly flips the quantum states using half wave-plate before sending back to the transmitter. The transmission of quantum states is made within a secret time interval which, based on preset path length and pulse travel time, triggers the detection device, and eventually achieves authentication after two more iterations. Index Terms- quantum channel, authentication process, photon polarization, deterministic states. I. INTRODUCTION uantum key distribution algorithms are implementations of certain quantum laws and principles for secure cryptographic applications. In QKD systems, users are enabled to have access to a quantum channel through which photons carrying secret information are exchanged securely. Therefore, the establishment of a secure authenticated quantum channel is one characterization of QKD systems which are physically realizable with optical fibers or free space optics (FSO). In general, one station (commonly known as Alice) prepares a sting of photons in certain quantum states and sends them to the intended stations. The receiver (commonly known as Bob), upon reception of photons, examines them in order to extract the encoded cryptographic key. The key is used to decrypt the cihper-text transmitted over the classical channels, e.g. internet. The quantum states according to the no-cloning principle can never be copied which means that any attempt of eavesdropping can be easily detected [1] In QKD systems, new cryptographic keys are created uniquely and randomly; then automatically shared between Alice and Bob [2]. The key is created from a string of 0s and 1s encoded based on photons‟ states of polarization. Single photon sources are not physically applicable; however, the additional path loss approximates the single-photon situation. Quantum bits (qubits) are the basic representation of quantum information. A qubit is a superposition of two different quantum states: The complex coefficients and are related by: Deterministic quantum protocols mostly implements the quantum entanglement phenomenon between two photons such that acting on one of them significantly alters the quantum state of the other; which therefore can be used as a security indicator for several services but more prominently for authentication. The remainder of this paper is organized as the following; section II presents related QKD work. In section III the simplification on the QAP-6DP is discussed. The results are shown and analyzed in section IV. Finally, discussion over quantum channel and conclusion are presented in sections V and VI respectively. II. QUANTUM PROTOCOLS Developing quantum protocols for cryptographic applications started in the 1980s. Different protocols are characterized by different security aspects and limitations. The most obvious limitation of earlier quantum crypto algorithms is mainly the physical realization; for example single photon sources and detectors. Years after, the realization of quantum entanglement has significantly enhanced security (e.g. source authentication) when implemented deterministically. The first quantum cryptographic protocol is BB84 developed in 1984 and named after Charles Bennett and Gilles Brassard. Both Alice and Bob are connected via two channels; classical channel and a quantum channel [3]: Alice prepares quantum states on a random rectilinear or diagonal basis then sends it to Bob. Bob measures the quantum states with a basis he chooses randomly. If the chosen basis matches, the corresponding bit is decoded correctly. Otherwise, a random result (0 or 1) with equal probability of half. In the public channel, Alice and Bob compare the decoded bits. Bits corresponding to mismatched bases are removed resulting in the shifted key. Finally, Alice and Bob obtain a joint secret key from the remaining bits by performing error correction. Q