METHOD FOR ESTABLISHING A DETOUR ROUTE IN A MULTIPROTOCOL LABEL SWITCHING NETWORK, PARTICULARLY FOR MINIMIZING DATA LOSS IN OCCURRENCE OF A FAILURE AND MAXIMIZING UTILIZATION OF NETWORK RESOURCES

摘要

PURPOSE: A method for establishing a detour route in an MPLS(Multiprotocol Label Switching) network is provided to effectively manage network resources by not establishing a BLSP(Backup Label Switch Path), namely, a detour route, until a failure occurs and maximize the efficiency of the network resources by selecting the detour route for recovering a failure based on network topology when a failure occurs. CONSTITUTION: When a transmission LER-A(Label Edge Router-A) transmits traffic(S2), a PLSP(Primary Label Switched Path) is set by way of an LSR(Label Switched Router)-B, LSR-D and LSR-F, and the traffic is transmitted to a reception LER-H(S4). When a failure is detected and if the failure is a link failure between the LSR-F and the LER-H(S6,S10), the LSR-F sets itself as a transmission LSR, the link between the temporary transmission LSR-F and the reception LER-H is designated as the first failure recovery interval(S12), and it is determined whether the temporary transmission LER is identical to the LER-A(S16). If they are not identical to each other, an optimum route for the first failure recovery interval is searched(S20). If the optimum route is successfully searched, detour route information is transmitted to every LSR belonging to the optimum route and each LSR stores the detour route information in an internal FIB(Forwarded Information Base)(S24). The LSR-F transmits the traffic through the detour route to the reception LER-H(S26).