Quantum cryptography

Li Fan

At the time when man enter the Information Age in the twenty-first century,how could we guarantee that the communications systems can't be decrypted? In this respect,quantum cryptography has made great progress.By analyzing the development of cryptography both scientifically and philosophically from the non-quantum cryptography phase to the quantum cryptography phase,we conclude that the ancient cryptography is of weak uncrackability,and when it developed into the stage of the classical cryptography its theory and practice take on the strong-uncrackability,while the quantum cryptography tends to be uncrakable,and it is gradually becoming imperatively uncrakable.

Nuno Crato

HE Xiang-chu

This paper first gives a brief introduction of quantum cryptography and several principal quantum effects involved by quantum key; then it describes in detail the development history of quantum cryptography at home, gives some topics in the research of quantum cryptography, including quantum key distribution, quantum signature, quantum identity authentication, quantum encryption, quantum secret-sharing, and their brief descriptions, and analyzes in depth some hindering factors in practical quantum cryptography; finally, the development of quantum cryptography is forecasted.

Toshio HASEGAWA, Tsuyoshi Nishioka, Hirokazu ISHIZUKA

Mustafa Toyran

In this paper, the elementary aspects of quantum cryptography are presented. First, we start with the introduction and history of quantum cryptography. Second, we give the definition of classical and quantum cryptography and emphasize the difference between the two. The idea of quantum cryptography will be explained further in the subsequent section, where the famous quantum key distribution example is presented. Lastly, we give the results of some computer simulations.