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:
May. 06, 1997
Filed:
Mar. 15, 1995
Morihito Miyagi, Tokyo, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A defect notification method and apparatus for use in a multipoint ATM network so as to avoid the transmission of defect notification cells in an overlapped manner. In the invention when a connecting point detects a defect in a lower layer and when the connecting point is not a branching point the connecting point sends a first defect notification signal in the downstream direction of a first connection. When the connecting point receives the first defect notification signal and when the connecting point is a branching point, the connecting point terminates the first defect notification signal, sends a quasi-defect notification signal in the downstream direction of the first connection, and returns a second defect notification signal in the downstream direction of a second connection in the opposite direction of the first connection. Connecting points in the downstream direction of the first connection transfer the quasi-defect notification signal in the downstream direction of the first connection without processing and end points, upon receiving the quasi-defect notification signal, execute a predetermined state transition.