Title:
量子暗号を使用するキー配送システムおよび方法
Document Type and Number:
Japanese Patent JP3756948
Kind Code:
B2
Abstract:
PCT No. PCT/GB94/01953 Sec. 371 Date Mar. 8, 1996 Sec. 102(e) Date Mar. 8, 1996 PCT Filed Sep. 8, 1994 PCT Pub. No. WO95/07583 PCT Pub. Date Mar. 16, 1995A method of communication based on quantum cryptography is modified to include an initial step of outputting from, e.g., a transmitter, a single-photon signal, which may be unmodulated. A receiver then randomly selects one of a plurality of encryption alphabets corresponding to different, non-commuting quantum mechanical operators. The receiver modulates the single-photon signal with the selected operator and returns the signal to the transmitter. The transmitter in turn randomly selects a quantum mechanical operator and uses that operator in detecting the returned signal modulated by the receiver. Alternatively, the transmitter may randomly select one of a plurality of encryption alphabets and use that encryption alphabet in modulating the signal. The signal is then further modulated at the receiver using a predetermined encryption alphabet. When the signal is received back at the transmitter, it is detected using the same quantum mechanical operator as was initially used to modulate it. Comparison is made of the states of the single-photon signals as transmitted and received to detect the presence of any eavesdropper.
Inventors:
Townsend, Paul David
Blow, Keith James
Blow, Keith James
Application Number:
JP50854295A
Publication Date:
March 22, 2006
Filing Date:
September 08, 1994
Export Citation:
Assignee:
British Telecommunications Public Limited Company
International Classes:
G02F3/00; H04B10/00; G02F1/1347; G09C1/00; G09C5/00; H04B10/07; H04B10/272; H04B10/275; H04B10/278; H04B10/524; H04B10/532; H04B10/54; H04B10/556; H04B10/572; H04B10/70; H04L9/08; H04L9/38; G02F1/139; G02F1/141
Domestic Patent References:
| JP5160794A | ||||
| JP4336829A | ||||
| JP2202732A |
Other References:
S. J. D. Phoenix and P. D. Townsend, “Quantum cryptography and secure optical communications”, BT Technology Journal, 1993年 4月,Vol.11, No.2, pp.65-75
Attorney, Agent or Firm:
Takehiko Suzue
Sadao Muramatsu
Ryo Hashimoto
Hanawa Yoshio
Sadao Muramatsu
Ryo Hashimoto
Hanawa Yoshio