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, 1992
Filed:
Mar. 30, 1990
Hajime Kawamura, Tokyo, JP;
Keisuke Kuroyanagi, Tokyo, JP;
NEC Corporation, Tokyo, JP;
Abstract
A data communication system comprises a network management center and switching nodes which are interconnected by regular and spare routes. Each of the regular and spare routes comprises data channels and a control chnanel, the data channels of the regular routes forming a data network for carrying signals to and from user terminals and the control channel of each regular or spare route is connected to the control channels of other regular or spare routes to form a control network of multidrop structure for carrying a network management signal from the center to the nodes as well as network response signals from the nodes to the center. Each of the nodes transmits a request signal through the control network in the event of a line fault in the transmission lines to request permission to establish a new regular route to an adjacent node and transmits a grant signal through the control network in response to receipt of a request signal from an adjacent node indicating that the request is granted if an alternate route is available. The control network is dynamically reconfigured in accordance with the presence and absence of the request signal and the grant signal received from adjacent nodes.