The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 12, 1996
Filed:
Dec. 29, 1994
Tomoyuki Ueno, Kawasaki, JP;
Mitsuru Seta, Kawasaki, JP;
Fujitsu Limited, Kanagawa, JP;
Abstract
An enciphered communication system is provided which has a plurality of cipher keys selectively used for enciphering data, wherein even when a cipher key number used at a transmitting side is not correctly transmitted to a receiving side, the receiving side can change the cipher key to a correct one. A transmitter has appendant data affixing means for affixing appendant data to information to be enciphered, and a receiver has appendant data detecting means for detecting the appendant data from deciphered data, and cipher key determining means for successively changing the cipher key of the receiver when the appendant data is not accurately detected. Consequently, when the cipher key is changed, for example, the receiving side itself can restore data even if the cipher key number is not correctly transmitted thereto.