Indian Quantum Communication Enabled Space Security

Quantum key distribution (QKD) is the most common secure techniques for exchanging key between two or more legitimate users using some insecure network. Despite much progress, ground-based secure communication systems using QKD is not feasible due to high atmospheric loss in free space communication where the range of communication may be extended. Thus, the physicists will be able to create satellite based QKD network for secure communication. This manuscript summarizes research and development from QKD protocols between two legitimate users to Ground to satellite based QKD network. It includes the progress of secure protocols using QKD around the world in respect with infrastructure, security and the technical challenges.