Server based QoS routing

We discuss schemes for a centralized implementation of a QoS routing protocol, where a route server is responsible for determining QoS routes on behalf of all the routers in a network. We argue that this centralized organization has some advantages, when compared to a conventional distributed link state implementation. We discuss techniques for efficient maintenance of QoS topology information at the server and for reducing the amount of requests for routes that the network will generate. Using a comprehensive cost model based on measurements taken from a real implementation, we evaluate the feasibility and the cost of server based QoS routing in a variety of network configurations. Our results show that such an implementation is well within the capabilities of off-the-self routing equipment.