An integrated anycast end-to-end QoS routing on DiffServ networks

An anycast service in a QoS-based network requires to setup paths with bandwidth guarantees and to select a server with capacity guarantees. This paper proposes an architecture which integrates both network layer anycasting service and application layer anyscasting service in order to select both a path and a server that satisfies the client QoS constrain in DiffServ networks. To perform a path selection algorithm, the proposed protocol uses the idea of residual capacity to select all paths which match the client bandwidth requirement. To perform the server selection process, each server resource management (SRM) uses server weight of each server to select a best server that has available capacity for the client request. Furthermore, the design of multiple SRMs eliminates the single point of failure and increases reliability in a DiffServ network. The simulation results have shown that the proposed protocol has much faster server response time and has lowest request blocking rate than other existing protocols, especially in the case where the traffic load is high.