| The development of mobile telecommunication is very rapidly in recent years. The development and update speed of mobile telcommnuication systems is also an amazing especially in the recent two deceads. Mobile communications radically meet people's growing need of exchange information anytime and anywhere. And the mobile communication's final destination is personal communication, that means everyone can communicate anywhere with any other people at any time in any way they want.With the rapid development of mobile communication technology and the widespread use of distributed technology, distributed systems are playing an increasingly important role in communication field. Because distributed systems are networking and isomerization, they can combine with mobile telecommunication. The emergence of middleware promotes more development of the distributed system. The middleware technology, CORBA (Common Object Request Broker Architecture), has become mainstream standards when we develop object-oriented distribution applications in network environment. OMG also puts forward a specification for mobile terminal and wireless access that can make CORBA technology play a role in the field of mobile telecom.But in the mobile communication field there are also some technical problems, such as resolving the core network's mobile IP in wireless communication and mobility management and so on. For mobile communication system, it still lacks support to rapid seamless handoff mechanism and the realization to the function of accessing and updatingand real-time positions. To solve these problems, we must adopt the new network structure and routing management optimization scheme and need to adopt efficient delivery and handoff protocol that must can well solve the problems that delay and loss of data.Based on CORBA technology, in this paper we combine the relevant knowledge of CORBA and mobile communication, and then make a design and implementation. First we analyze the background of this research subject, and analyze the present research circumstances at home and abroad. Then we introduce some knowdedge about CORBA technology and mobile communication. Then we detailed introduce communication model of CORBA and make a deep research to communication protocol of CORBA. At the last we make a detailed studie to GIOP message and GTP protocol and make a study to each component of architecture that CORB A application in mobile communication, then analyze handoff mechanism between mobile terminal and network. We also make design and implementation to relevant interfaces of handoff mechanism. We give two different handoff patterns of handoff mechanism, their timing diagram, and flowchart and IDL language description of each interface, and implement them. At last we propose a new model named WAP-CORBA, and illustrate its services. |
