We describes the extensive applications of Photonic Bandgap-photonic Crystal Fibers in High-power laser beam transmission, particle transfer, sensor and soliton compression in detail.

The research of multiplexing and transmission efficiency of SDH;

Study on the transmission efficiency of optic fiber probe;

Transmission efficiency of high power density soft X-ray through capillary;

The key idea of the improvement is to increase the transmitting efficiency through the third common public channel without affecting the safety of quantum cryptographic key distribution protocol.

Its main idea is to find secret listener-in from trap and improve the transmitting efficiency.

The paper,under the premise of guaranteeing the security in practice,introduces a compromising method to improve the transmitting efficiency by way of decreasing the degree of cryptograph security in quantum communication,which is also a more practical method to balance the transmitting efficiency and the transmitting authentication.