In order to accommodate the new generation of Internet applications, routers need to be designed to support QoS, policy based management, and mobility. This paper presents an architecture for the control plane of a software router that integrates signaling protocols and control mechanisms for QoS, policy based management, and mobile IP. The architecture has the flexibility of using policy control to dynamically configure routers to act as nodes in an IntServ or DiffServ domain. Within each domain the routers can be configured to control their resource usage or to implement Service Level Agreements. Implementation of a software router based on Linux and the experimental results are presented. The results show that with software routers this architecture can be used to meet the end-to-end QoS performance for most Internet applications.