End-to-end QoS guarantees over Diffserv networks

The integrated services (Intserv) architecture provides the Internet the ability of delivering end-to-end QoS to applications over heterogeneous networks. Existing approaches for providing Intserv require routers to manage per flow states and perform per flow operations. Such a stateful network raises the scalability concerns when the network size or the number of flows is significantly large. The differentiated services (Diffserv) approach proposes a scalable means to deliver IP QoS based on aggregate traffic handling. We present end-to-end QoS guaranteed services over Diffserv network. This is implemented by introducing an sender-initiated resource reservation mechanism over Diffserv. This way we simultaneously achieve scalability and better control on the services. We present a detailed experimental study of the end-to-end QoS behaviour. Our results demonstrate that it is very desirable to implement the reservation mechanism over Diffserv to achieve more flexible and efficient end-to-end guaranteed QoS.