Research And Implementation Of Corba Object Transaction Service (ots)

The coexistence of heterogeneous entities in the large scale distributed systems makes it more and more difficult to develop distributed applications. CORBA provides distributed objects the ability of transparent interaction even if they are on different platforms or written in different language,so recently it becomes an important research field in the distributed computing domain. The Object Transaction Service(OTS) brings the powerful computing concept of transaction processing into CORBA and it assured the integrity and reliability of the interaction between distributed objects. The paper does some research on the CORBA and distributed transaction processing, and an implementation of OTS is presented.Firstly, the architechure of CORBA is described, including object request broker, interface define language, interface repository and implementation repository, language mapping, stub and skeleton, object adaptor, etc. And the concept of transaction is introduced, including the two-phase commit protocol of distributed transaction. Then it addresses the specification of OTS in detail and the software architechure of transaction processing in OTS is analyzed.In the following the Portable Object Adapter is studied, which is the key to write scalable and high-performance CORBA server. Using Object-Oriented method it designes the objects in the OTS , describes the functions and relations for each object, analyzes how those objects coordinates to implement the transaction processing.X/OPEN defined the Distributed Transaction Processing model in 1991 , the XA interface in which was supported by most database manufacturers such as Oracle, IBM, Sybase and Microsoft. Finally how to integrate the XA-compliant resource manager with OTS is studied and implemented.Based on the research and development given above, an available object transaction service(NOSEOTS) is implemented for a CORBA middleware ?NOSEware.