NODE DEVICE FOR ATM COMMUNICATION NETWORK AND FAILURE ALARM NOTIFYING METHOD

摘要

PROBLEM TO BE SOLVED: To quickly send an AIS to the downstream side by extracting and using a VPI(virtual path identifier) of an up direction cell header when a down path has a failure and a virtual path-failure alarm signal VP-AIS cell is sent in the down direction via a circuit processing interface part. ;SOLUTION: When a circuit failure occurs at the upstream side of an ATM communication network, a circuit receiving part 511-1 receives no data and the receiving signal cutoff is detected and notified to a cell extraction/generation part 517-1 via a failure notifying part 512-1. Thus, the notification is decided for detection of the circuit failure. Then a cell put on a circuit to be paired with the faulty circuit is copied, and the VPI that is written into the header of the copied cell is extracted and written into the header of a VP-AIS cell. The VPI is transferred to an ATM switch 502 from a cell inserting part 515-1. The VP-AIS cell is continuously transferred to the part 515-1 at a prescribed interval until the recovery of failure is notified and then multiplexed with an ordinary user data cell.;COPYRIGHT: (C)1999,JPO