量子密钥分发技术的机遇与挑战

The Opportunity and Challenge On Quantum Key Distribution

量子密钥分发(QKD,quantum key distribution)具有理想的理论安全性,近十年来得到了快速发展。但是,理论上被证明完美的技术并不意味着一定能够实现完美的应用。一方面,越来越多的研究表明,旁路攻击将是QKD系统的一个主要威胁,而且针对实际QKD系统的旁路攻击才刚刚开始。另一方面,由于量子信号的传输不像经典电磁波那样具有很大的灵活性,致使QKD很难与传统通信网络进行无缝对接,也很难在广域网中得到广泛作用。另外,QKD也不能解决身份识别和数据存储安全等问题。因此,构建一个完善的QKD系统安全及其测评体系将是QKD得到实际应用的重要因素,而构建一个完善的抗量子计算的新型密码理论体系将是确保未来信息安全的关键。

In last decade, many important results on quantum key distribution（ QKD）have been achieved. QKD is physically secure in theory, however, it is not easy to realize an ideal QKD system in practice. On the one hand, side channel attack on QKD system will be a main threat which cannot be eliminated in the predictable future. On the other hand, QKD system does not have a full compatibility with conventional network because quantum signal is transmitted by fiber or free-space in point to point mode. Besides, the security of identification and data storage still cannot be solved by QKD. However, an integrated system on how to evaluate the security of QKD systemstill will play an important role in practical QKD system. Espe- cially, new cryptography system is still the key factor toward the bright future of information security.