In a packet switched communications transport network a method for re-routing traffic flow is provided. The invention based on the recognition of actual utilization of transport resources. In accordance with the implementation, Fast Re-Route detour paths are recalculated each time after new bandwidth information is received. The detours are re-established on new computed paths if needed, i.e., if an optimized path has been found. A node and a system are also disclosed, referring to MPLS network. Also a node is described acting as a Point of Local Repair for link failures. The node comprises a Routing engine, a Link state database, a Detour path calculator and a Detour path establisher in order to capture bandwidth information of the network links and to calculate detour path information for the nodes.