| Satifying with QoS requirements of beared services and making any users obtain services with QoS guarantee anytime and anywhere, is one target of designing networks. With the broadband development of mobile telecommunications network and the mobility development of broadband wireless networks, all-IP heterogeneous networks coexistence and integration is becoming an important feature of next generation wireless networks. In the all-IP integrated networks, multiple networks coexist. Various networks have different transmission rates, channel characteristics, system capacity, resource conditions, QoS classifications, resource reservation methods and so on. The capabilities and methods to bear services are different from each other. To meet the high QoS requirements for next generation heterogeneous networks in service access, end-to-end establishment and maintenance, and even in mobile scenarios, are the key problems to realize the seamless integration of wireless heterogeneous network.The thesis firstly summarized the development and evolution of wireless networks and analyzed the all-IP trend of future networks. Definition and classification of QoS were also explained. Moreover, QoS related technologies were investigated in mobile telecommunication and IP networks. The difficult problems in end-to-end, access and mobile scenarios for QoS guarantee for all-IP heterogeneous networks were also addressed on.In the aspect of end-to-end QoS, the thesis defined an end-to-end QoS provisioning framework, which based on policy and NSIS (Next Steps in Signaling). Vertical management in intra-domain and horizontal signaling negotiation between different network domains were also defined in detail. Based on the proposed framework, the thesis proposed an end-to-end SLA negotiation mechanism taking use of least mean square algorithm. According to the error between measured and negotiated ideal performance along end-to-end path, the proposed mechanism can adjust the level of service in different QoS domains adaptively. Simulation results proved that the proposed mechanism can adjust level of services adaptively, negotiate between different network domains, and satisfy with the QoS requirements along end-to-end path.In the aspect of service access, the thesis proposed hierarchical joint admission control mechanism (HJCAC, Hierarchical Joint Call Admission Control) for heterogeneous integrated networks. Two entities, which included LCAC (Local call admission control) and HJCAC (hierarchical joint call admission control), were added in the side of networks. LCACs and HJCACs cooperated with terminals to make the admission decision and selected the best network for service to access. Traditional admission control policy in each network did not need to make any change. Simulation results proved that proposed mechanism can unify resources in every network, improve the acceptance ratio by 10.96% in light load and 4.71% in heavy load. Moreover, the thesis proposed an adaptive access mode selection algorithm. Mobile terminals can choose access mode between multi-hop and cellular mode by monitoring the interface performance periodly. Simulation results indicated the proposed algorithm can select the most appropriate mode to access the network, enhance the network throughput and keep the fairness among different multimode terminals.In the aspect of mobile scenario, a mobility-aware QoS signaling mechanismQNFH (QoS NSLP with FHMIPv6) was proposed. The aim of the proposed mechanism was to solve the double reservation problem in mobile environment for traditional QoS signaling. The proposed mechanism associated the FHMIPv6 with NSIS. L2 location information can trigger the L3 handover and the resource reservation in advance. Once the L3 handover finished, only the activation of stateless reservation along the previous reservation path was needed. With the increase of hops in the common part of new path and old path, the proposed mechanism can reduce the reservation re-establishment delay by 1.06ms and signaling re-establishment cost by 1.87% for each hop in C-mode. In D-mode, the proposed mechanism can reduce the reservation re-establishement delay by 0.98ms and signaling cost by 1.09% for each hop.In order to solve the conflict between slow routing algorithm convergence rate and rapid change of network topology, an intelligent QoS routing algorithm based on location information was proposed. The proposed algorithm took use of ant colony algorithm. Location judgement function was added in the tabu list in order to reduce the search area. Also the location related information and QoS requirement information were added in the heuristic function, which can force the algorithm to converge to the best solution. Comparing with traditional algorithm, simulation results verified that the proposed algorithm can not only find the best path for the algorithm, but also improve the convergence rate of the algorithm by 36.96%.Finally, the summary of the thesis was given. The shortcomings of the research were pointed out and suggestions for future research were also listed.
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