Abstract: A simple technique to secure quantum key distribution relay networks is presented here. The paper introduces the concept of logical channels that uses a random dropout scheme. The paper also presents an enhanced protocol for key distribution in the relay networks. Previous techniques relied on creating distinct physical paths to create shares. Hence the compromise of one relay must compromise the entire channel. The concept of logical channel ensures that an attacker must compromise all the relays in order to access the key.

Keywords: Quantum cryptography, Quantum Key Distribution, Relay networks, Random dropout