Router-based traffic engineering in MPLS/DiffServ/HMIP radio access networks

We proposed and evaluated a traffic-engineering algorithm for use in Internet Protocol (IP) radio access networks. The goal of the traffic-engineering algorithm was to reduce network congestion while increasing the availability of QoS, when compared to traditional routing techniques like current IP routing. This traffic-engineering algorithm was required to be as simple and fast as possible, and place very little demand on the network resources. The radio access network used Multiprotocol Label Switching, Differentiated Services, and Hierarchical Mobile IP to support mobile nodes. The traffic-engineering algorithm was router based. Routers on the edges of the network made the decisions about on to which paths to place admitted traffic. Sets of label switched paths were set up between all destinations in the network upon instantiation of the network. Using only local QoS state and network physical design information, each router determined its share of the radio access network core bandwidth using a proposed bandwidth allocation algorithm. Each router then used a widest-shortest path decision method to choose paths from the already established path sets. Our evaluation compared this traffic-engineering algorithm to standard IP routing and a similar algorithm that used global QoS state. We determined that our traffic-engineering algorithm performed very well across a wide range of network conditions. In most cases it outperformed current IP routing as measured by QoS parameters. Its performance was generally quite close to that of the global QoS state algorithm.