Information Security is a major problem nowadays because the information contains personal info, company's transactions etc., and with that information anyone can harm anyone's life. Every System in the world tries to peer into the network and want to manipulate or want to access the data. In addition to this nowadays IoT, IoE came into picture where people's personal data can be gathered. Mainly in IoE, people's data is given high importance. So, there is great need of providing security for the data. In this kind of situations, Cryptography plays a key role to protect the data. Classic Cryptography algorithms like RSA, ECC are not more efficient in protecting the data as they are based on mathematical calculations. These mathematically based algorithms may be decrypted in one or other way. So, to enhance the security for data, Quantum came into the picture. This Quantum Cryptography is more efficient when compared to other algorithms as it is based on the concept Quantum Entanglement and Heisenberg uncertainty principle. This paper deals with all aspects of quantum key distribution which are major primitive for Quantum Cryptography along with Quantum Key Distribution Protocols used for developing IoE security.
