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:
Jul. 14, 1987
Filed:
Nov. 09, 1984
Satoshi Ikeuchi, Kawasaki, JP;
Ikuo Taniguchi, Inagi, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A line protection switching system of improved reliability decreases the time for protection line switching. In order to increase reliability, service signals are sent in parallel via a plurality of transmission lines, using a service bit area of PCM bit frames. The system switches a failed transmission line to a stand by line, at a local station where trouble is detected without waiting for the switching of an opposite station. At the same time, a switching command is sent to the opposite station. If the switching of the opposite station fails, the local station commands a retry of the switching operation. If it again fails, the local station returns the transmission line to the initial state. In addition, a low priority signal is transmitted through the stand by line, so that the total system operates more economically.