ES-TMP: Inter-Domain Egress Selection Based on Traffic Migration Prediction

Abstract

Hot-potato routing is commonly used to break tie among multiple equally-good exit points associating with inter-domain BGP routes. However, hot-potato routing only takes the network control plane into consideration, where it provides the routers the possibility of enabling early exit of traffic using barely protocol-related information of IGP distance. In this paper, we argue that egress selection of inter-domain routing should pay more attention to traffic forwarding, because the large traffic migration caused by egress change, although not quite often, can degrade the network performance or even make the network crash. We propose Egress Selection based on Traffic Migration Prediction (ES-TMP). We use traffic demand to predict the traffic migration, which is used as important criteria for egress selection. If the volume of traffic migration is large, ES-TMP keeps the egress unchanged. Otherwise, the small traffic migration enables the routers use the closest egress without apparent influence on network performance. ES-TMP can either be implemented with standard BGP protocol or by dedicated servers to perform global routing optimization.