Patent ID: 7596094

Claim:
In an ATM network carrying an ATM connection across a core MPLS network in a label switched path (LSP), an ATM/MPLS edge node for notifying the ATM network of a failure in the LSP, the edge node comprising: an MPLS interface for monitoring operation of the LPS, and generating a failure state indication if the failure affects a routing path across the MPLS network or a MPLS port of the routing path on the edge node; an ATM interface for generating and transmitting an ATM OAM alarm indication signal (AIS) packet on receipt of the failure state indication; and, a controller for monitoring operation of the routing path within the edge node, and operation of the ATM and MPLS interfaces; wherein the MPLS interface transmits the ATM OAM AIS packet transparently over the LSP when the failure affects the MPLS port of the routing path on the edge node, and generates and transmits an MPLS OAM forward defect indication (FDI) packet over the LSP when the failure affects the routing path between the ATM network interface and the MPLS network interface; and, wherein the MPLS network interface comprises: a MPLS GAM state machine for each LSP tunnel originating at the edge node for receiving an MPLS OAM frame indicating a change of state of operation of the routing path carried in a LSP tunnel across the MPLS network; and, an OAM task module for placing change of state signals from all MPLS QAM state machines in a queue and for informing a LSP management system of each change of state in order.