Research On Key Technologies Of Network Adaptation Layer For Modern Service Industry

Modern service industry is not only a new strategic industry but also a new growth point for the development of national economic and social development. And then information and communication technology is the engine and platform of modern service industry. The goals of national "Eleventh Five-Year Plan" projects are to create a common technical support system and application demonstration environments. Thus, the requirements put forward new demands and challenges for the supporting platform of modern service industry. In this dissertation, a research method is adopted based on theoretical analysis, experimental simulation and plat-form software development to discuss some key issues, which include system ar-chitecture and interface, capability adaptation, intelligent handoff, admission con-trol and load balancing and other related technologies. The innovations of this dis-sertation are concluded as follow.Firstly, according to the applications of modern service industry, a new system architecture is proposed based on the network adaptation layer for heterogeneous networks, and a set of standard interfaces are defined by modifying Parlay X APIs and raising new service interfaces. Furthermore, the architecture and the interfaces have been applied to setup the platform for modern service industry. Network Ad-aptation Layer realizes the network capability abstraction from data plane, man-agement plane and control plane, which is lied between Access Network Layer and Service Layer. It is used to shield the complexity of the underlying heterogeneous network downward to support the telecom networks, the Internet, satellite and other network access technologies, and to expose the standard service interfaces upward to realize the applications of modern service industry.Secondly, in order to meet the needs of multi-networks and multi-terminals, a new management method and a capability adaptation algorithm are proposed to achieve user-center personal mobility. The management method builds a "user- terminal-network" of multiple correlation mechanism to manage the users and ter-minals especially when one user has several terminals. Capability adaptation algo-rithm can collect users, terminals and network information by network measure-ment, and select the optimal network and the ideal terminal for the user considering the user preferences, service QoS parameters, network status and other factors. Simulations show that that the algorithm can effectively manage the users and ter-minals and select the best available network and terminal.Thirdly, according to the requirements of service continuity for modern ser-vice industry, an intelligent handoff algorithm based on capability adaptation is proposed to realize the seamless handoff across terminals and networks. The objec-tive network and terminal selected by capability adaptation module are compared with the current ones to determine the handoff type. And then the handoff proc-esses across networks and terminals are implemented based different handoff sig-naling flow, which includes network vertical handoff, terminal handoff and joint network and terminal handoff. Simulations and platform tests are conducted ac-cording to the corresponding handoff functions, which can ensure the service con-tinuities and user's QoS performance.Fourthly, because the application of modern service industry includes a vari-ety of different service types, utility functions are defined respectively for different services, and call priorities are defined according to different call types such as a new service call and a handoff call. Therefore, an admission control algorithm and a load balancing mechanism are propped based on the pre-estimation of utility gain, which respectively achieve admission control for the new call and handoff call and to make heterogeneous networks balanced on traffic load. Simulations shows that the can improve the total system utility, drop the call blocking probability and en-sure the QoS performance of the business.In sum, the contents of this dissertation are discussed as a part of the modern service industry project, and simulations and analysis are taken to illustrate the key technical schemes and algorithms, which have been applied to the development and implementation of demonstration platform. The demonstration base is estab-lished to provide an effective instruction for the further development of modern service industry.