Resilient network admission control

Network admission control (NAC) limits the traffic in a network to avoid overload and to assure thereby the quality of service (QoS) for admitted flows. Overload may occur due to exceptional traffic demand, but it is mostly caused by redirected traffic due to link failures. Conventional NAC methods cannot cope with network outages and fail when they are needed most. This paper categorizes existing and new NAC methods and makes them resilient to network failures by a resilient resource management. We compare the efficiency of the NAC methods with and without resilience requirements and show that they have a significant impact on the required backup capacity when resilience is required.