From Quantum Cheating to Quantum Security

The contest between code-makers and code-breakers has been going on for thousands of years. Recently, quantum mechanics has made a remarkable
entry in the subject. On one hand, quantum computing can break standard
encryption schemes, thus threatening the very foundation of data security.
On the other hand, quantum cryptography can come to the rescue by allowing
perfectly secure communication guaranteed by the laws of physics. However,some cryptographic tasks such as bit commitment have been shown to be
fundamentally impossible, even with the help of quantum mechanics. Here, I survey the power and limitation of quantum cryptography. I also remark that quantum cryptographic products are currently available in the commercial market.

Hoi-Kwong Lo received his Ph. D. in Physics from the California Institute of Technology in 1994 respectively. From 1994 to 1996, he was a Member of the School of Natural Science, the Institute for Advanced Study, Princeton. In 1996, he joined Hewlett-Packard Labs, Bristol, UK as a postdoctoral fellow. In 1997, he became a Senior Member of Technical Staff there. In 1999, he took up the posts of the Chief Scientist and Senior Vice President of MagiQ Technologies, Inc., New York, which is a leading company in the commercialization of quantum information. In January 2003, he joined the University of Toronto as an Associate Professor, in both the Department of Electrical and Computer Engineering and the Department of Physics. His current research interest is quantum information, particularly, quantum cryptography. He is currently a consulting scientist for MagiQ Technologies, Inc. http://www.magiqtech.com/ He is a Founding Managing Editor of "quantum Information and Computation" (QIC), http://www.rintonpress.com/journals/qic/index.html which is a leading journal in the field. He has co-edited two books on the subject and published many original and survey articles in quantum information. He is currently a holder of a Canada Research Chair in Quantum Information. He is a co-winner of the 2003 Outstanding Young Researcher Award (OYRA) from Overseas Chinese Physics Association (OCPA).