Research On Quantum Key Distribution Technology In TT&C Network

Space TT&C network uses wireless channel to transmit information. To improve the security in wireless channel, this paper uses the quantum key distribution technology to get a shared key that is used to encrypt information to keep it from being tapped. Quantum key distribution technology is an emerging technology, which combines the shared key which can’t be tapped and one time pad which can’t be cracked. Both sides of the communication can detect any eavesdropper by bit error rate increasing abnormally and keep it safe in space TT&C network.BB84 protocol is the first quantum communication protocol which uses single photon’s polarization to transmit information to keep the process of generating shared key safe. As the quantum channel being susceptible to be interfered by noise in the quantum key system of space TT&C network, there will be a certain bit error rate even without eavesdroppers in the shared key. As a result, the error bits should be dropped on classical channel using reconciliation method. To improve the efficiency of reconciliation, this paper has improved the protocol binary in reconciliation with CRC and MD5 to find error bits separately. In the self-designed simulation platform, the results show that the efficiency has improved a lot and cut down the time of generating shared key.This paper presents a model of application of quantum key distribution technology in distributed space TT&C network with the method of delay tolerant network. It sets up the quantum key distribution system between ground station and artificial satellite and uses artificial satellite to encrypt the key and transmit it as an agency to make two ground stations get shared key safely. The shared key is used to encrypt the information in public channel to keep it safe. In the process of transmit shared key, in view of the characteristic of delay tolerant network, this paper has improved the epidemic routing algorithm and simulated it with computer. The result shows that the efficiency of epidemic routing algorithm after improvement has increased a lot.