Quantum Encryption Algorithm Based on Modified BB84 and Authentication DH Algorithm

This thesis will describe two main contributions to quantum cryptography. First of all the well-known BB84 protocol for quantum key exchange is modified to eliminate the originally high bit error rate completely without compromising on the security. As the classical channel is the only place where eavesdropping could be possible, any attempt to eavesdropping is prevented. Secondly, the Quantum Linear Feedback Shift Register is proposed as a tool to generate the key matrix for the classical Hill-Cipher algorithm. Finally, all proposed methods are combined in an encryption process, proving to be secure, i.e. the resulting quantum encrypted message is less susceptible to attacks as shown in the detailed security. Keywords : Network security, Quantum cryptography, Quantum computing, BB84 Protocol, Quantum encryption algorithm , polarization filter, Multi-qubit Quantum shift register matrices,.