DiffServ operational model

RSVP (ReSerVation Protocol) is the signaling protocol defined by IETF (Internet Engineering Task Force) to guarantee QoS (Quality of Services) per flow in IntServ network. This paper presents a simple and yet effective new RSVP/COPS signaling model to support the delivery of end-to-end QoS across IntServ network and DiffServ domain. In this model the end-to-end RSVP messages are carried in the content of COPS (Common Open Policy Service) across DiffServ domain, which eliminates the requirement of both COPS-PR (COPS usage for Policy Provision) and COPS-ODRA (COPS usage for Outsourcing DiffServ Resource Allocation) protocols. An admission control algorithm has also been developed in this model for bandwidth broker to check QoS parameters when communicating with routers and to dynamically provide resources provisioning for DiffServ domain. The new model along with statistical methods are applied to analyze the typical DiffServ operations and to compute the probability of directional Internet flow moving from one router to another. Simulation result shows that the proposed model can provide lower setup time than others.