Secure sharing of secret key on insecure channel using Quantum key distribution

In today’s era of internet and network application, need for security has become of vital importance. Most of our important data is stored in computer and recently on cloud, also whenever we need to send data to some other person, we make use of internet thus, need of data security becomes increasingly important. Protecting important sensitive data against any unauthorized access is a major concern. Cryptography is one of the methods to safeguard all our important data from being stolen or intercepted by unwanted person. We can rely on classical cryptography for securing our data however, with the advancement of computation they are being phased out. Therefore, Quantum Key Distribution promises a secure key agreement by using law of quantum mechanics thus, QKD becomes a significant trend of new cryptographic revolution. This paper explains how QKD is used for secure sharing of key between two entities i.e. Alice and Bob and further using this shared key for encryption and decryption of text data. In addition to this, paper also discuss about implementation of QKD-BB84 protocol and test result indicates that QKD is secure against man-in-the-middle attack. However, physically implementing QKD is a greatest challenge due to need of Quantum computers and cost of setup