%0 Journal Article
%T Eavesdropping on the `ping-pong'' quantum communication protocol freely in a noise channel<br>Eavesdropping on the＇ping-pong＇ quantum communication protocol freely in a noise channel
%A Deng Fu-Guo
%A Li Xi-Han
%A Li Chun-Yan
%A Zhou Ping
%A Zhou Hong-Yu
%A <br>邓富国
%A 李熙涵
%A 李春燕
%A 周萍
%A 周宏余
%J 中国物理 B
%D 2007
%I 
%X We introduce an attack scheme for eavesdropping freely the ping-pong quantum communication protocol proposed by Bostr\"{o} m and Felbinger Phys. Rev. Lett. 89, 187902 (2002)] in a noise channel. The vicious eavesdropper, Eve, intercepts and measures the travel photon transmitted between the sender and the receiver. Then she replaces the quantum signal with a multi-photon signal in the same state, and measures the returned photons with the measuring basis, with which Eve prepares the fake signal except for one photon. This attack increases neither the quantum channel losses nor the error rate in the sampling instances for eavesdropping check. It works for eavesdropping the secret message transmitted with the ping-pong protocol. Finally, we propose a way for improving the security of the ping-pong protocol.
%K quantum communication
%K ping-pong protocol
%K eavesdropping<br>量子通信
%K 乒乓协议
%K 干扰信道
%K 偷听
%U http://www.alljournals.cn/get_abstract_url.aspx?pcid=6E709DC38FA1D09A4B578DD0906875B5B44D4D294832BB8E&cid=47EA7CFDDEBB28E0&jid=CD8D6A6897B9334F09D8D1648C376FB4&aid=FF458534E88FE56F7D84090AFE4B7FE5&yid=A732AF04DDA03BB3&vid=7801E6FC5AE9020C&iid=0B39A22176CE99FB&sid=CAA7BAE04CB631A1&eid=C1B34927D429E92F&journal_id=1009-1963&journal_name=中国物理&referenced_num=0&reference_num=47