NODE TO BE USED IN AN ASYNCHRONOUS TRANSFER MODE (ATM) TRANSMISSION SYSTEM

摘要

PROBLEM TO BE SOLVED: To attain high speed restoration within a processing limit at a cost of a node with protection switching for each virtual channel by utilizing a node that recognizes a defect specific to ATM and employing a virtual path group technology allowing'ltigh speed ATM virtual connection/restoration with a minimized processing. SOLUTION: Supposing that a physical layer defect takes place between a virtual path group(VPG) source node 101 and a VPG intermediate node 102, the VPG intermediate node 102 uses a transmission path/ATM adaptive function to detect the defect and generates a virtual path segment level alarm instruction signal (VP-AIS) cell for all virtual path identifiers(VPI) receiving the effect and inserts the signal to a cell stream. A VPG SYNC node 103 monitors continuously the reception of the VP-AIS and a VPG selector selects a protection VPG upon the receipt of it. Thus, high speed restoration is attained through protection switching or each virtual channel within a processing limit at a node cost.