Mapping application service into transport service and its QoS assurance issues

Internet only provides users with best effort services, today, with the development of next generation Internet. next generation Internet will provides users with tremendous services, how to manage these tremendous services and provides users with differentiated services automatically, must be solved for service providers and network providers. A two planes' service management architecture is proposed, the one is application service management based on application plane, and the other is transport service management based on transport plane. In this paper, mapping application service into transport service and issues for QoS are studied, primarily. It is well known that different application services correspond to different QoS requirement during they are transported in network, likewise, the different users need different QoS requirement for the same application service. Therefore, Firstly, application services are classified, and QoS requirement for different application service is studied; secondly, the NPLs(Network Performance Level) are studied, and draw a conclusion, if NPL array corresponding to application service is assured in network, the application service of quality can be assured also. Thirdly, as an interface between application service and transport service can be expressed in policy, thus, mapping application service into transport service can be implemented by configuring the policy. Finally, WFQ (Weighted-Fair-Queue) algorithm is researched primarily based on DiffServ, and several simulation models based on NS2 are designed and different algorithms are simulated, the simulation results show that different application service of quality can be assured by corresponding to scheduling algorithm in DiffServ mechanism model. By means of policy idea, the complicated issues for mapping application services into transport service can be solved, and different scheduling algorithm in DiffServ are fit for different application services' QoS assurance.