The Research On Core Realization Technology And Architecture For DiffServ Model

DiffServ model is one important model of the IP QoS, this model works on the basis of packet classification granularity , so it can overcome the limitation of the IntServ/RSVP model and it is easy to be realized on the big networks. Di ffServ model is composite of data path and control path, the data path finishes packet pretreatment and forward while the control path finishes resource manage. The thesis ,on the basis of the DiffServ model architecture, study the key realization technology of the data path and control path.On the aspect of data path, this thesis focuses on the realization technology of the traffic conditioner and PHB. Traffic conditioner's key logic components is the meter and shaper, according to the analysis of the theory basis to realize ihe two logic components and the present algorithms limitation in detail, the thesis designs related algorithms to upswing the present algorithm. PHB is the core component of DiffServ model. According to PHB's characters, the thesis firstly give out packet hiberarchy scheduling method, this method can be f lexibl y realized and efficiently deals with burst data. Buffer manage is anther important mechanism to realize PHB, the thesis emphatically analyses active buffer manage algorithms and gives out new muti-level buffer manage algorithm-QPRED and VPRI:D algorithms, this two algorithms are fit to DiffServ model needing of priority and realize fair buffer manage on the basis of priority.The difficulty of DiffServ model control path is to realize end to end resource manage. On the basis of resource reserving method, this thesis give out two level muti_agents resource manage mechanism, and in order to realize communication among different nodes, it modifies RSVP and COPS protocol to contain DiffServ model characters. This resource manage mechanism avoids the present mechanism's difficulty to be realized and it can efficiently finish end to end resource manage of DiffServ model.