Based On Key Technologies And Implementation Of Corba Distributed Communications Management System

With the development of network technology and computer applications, distributed system has become the most popular software system of many industries. Distributed system has many advantages, but it also faces a lot of challenges during the development. These challenges include: how to make users access the remote resources of heterogeneous platforms expediently, how to improve the reliability and the capability of fault tolerance, how to realize the openness of distributed system, how to improve the scalability of software structure and the reusability of code, how to solve the problem of cross-platform development, how to manage the resources in distributed systems effectively and so on. With these problems really solved in the design and implementation, distributed system will be able to exert a huge advantage.It's an effective way to solve the above problems by applying the middleware technologies to distributed systems. Intergrating the middleware into system according to a specific architecture, the differences between distributed platforms can be shielded, and the design and implementation of upper applications will be easier. CORBA is an excellent representation of middleware technologies. This thesis studied and analyzed the technical characteristics and related concepts of CORBA, and finally applied it to a specific distributed communication management system. Core modules of this system were completed and the implementations were studied, while the application effects were tested and analyzed also.This thesis first analyzed a variety of popular middleware technologies and illustrated the advantages of CORBA by contrast. After listing the challenges of distributed dystem development, this thesis preliminarily proposed the feasibility of dealing with these challenges using CORBA and other related technologies. Next,this thesis introduced the theories and technologies related to the topic:Introduced related concepts and technical characteristics of CORBA; introduced the basic knowledge of ACE and analyzed its supporting effect to CORBA programming; introduced related concepts of framework and analyzed its relationship with design patterns. Finally, this thesis analyzed and studied the design, implementation and applications of the core modules in this distributed communication management system in detail, including CORBA framework, reliability guarantee layer and resource management module. Among them, CORBA framework shielded the access details of heterogeneous platform resources, and achieved access transparency by encapsulating the standard CORBA interface.CORBA framework improved the scalability of software structure and the reusability of code by importing design patterns and the thought of framework. At the basis of CORBA framework, reliability guarantee layer layer designed and implemented the functional reconstruction strategy and files deployment algorithm, which provided fault-tolerant function for distributed system and a good solution to the problem of failure transparency. Resource management module is also based on the CORBA framework.It designed and implemented a distributed resources management model, which provided a simple and effective function to manage the distributed resources.In addition, all these core modules conformably used the ACE interface while using thread operations, UDP communication, timer and other APIs closely related to the operating system, which improved the portability of code and solved the problem of cross-platform development of distributed system. Reliability guarantee layer and resource management module completed object-oriented interface design by using OMG's IDL language, which ensured the openness of the distributed system.