Research On Several Key Technologies Of Web Services Based SBA System

Simulation Based Acquisition (SBA) is a new theory and method of defense equipments acquisition. By apply modeling and simulation (M&S) technologies to all stages of the acquisition process collaboratively, SBA can make the acquisition of complex products and equipment better, faster and cheaper. One of the prerequisites to implement SBA is the support of a robust information infrastructure, which should achieve on-demand access to information in a timely manner, interoperability of M&S tools and resources, collaborative working of participate, and so on. However, there is a lack of such information infrastructure currently. Fortunately, web service is a service-oriented distributed computing technology, with features of modular, loosely coupled and platform-independent. And it has advantages in the realization of wide-area, heterogeneous cross-platform software system, which meet demand of information infrastructure for SBA. In this dissertation, web services are utilized to construct architecture of SBA software support system, and the dissertation focuses on some key technologies, such as dynamic forecast of Quality of Service (QoS) and double access control for web service.Firstly, as domestic acquisition process was serial-style, a spiral-style process for SBA of complex product is designed, which adopts concurrent engineering. Furthermore, the dissertation proposes a web service based software architecture for SBA, and then discuss some major research thrusts: quality of web service, web service based system security, etc.The QoS of Web service is affected by many factors and they change frequently, and it is a challenge to collecting QoS timely for other QoS-based researches. Thus, it presents a feedback-based web service QoS dynamic collection method (FQCM). FQCM extends UDDI to UDDI-Q, which has capability of collecting and storing QoS information from service requesters. Without changing UDDI, UDDI-Q appends some QoS-related functions and interfaces, and it is compatible with the classic web service architecture.Web service QoS forecast can be combined with collected data to improve QoS assessment quality and to reflect the trends of web service QoS timely, but research of Web service QoS forecast in domestic is still at an initial stage. By introducing bayesian dynamic model, the dissertation proposes a novel QoS forecast method of web service and describe the forecast steps of dynamic linear model. The dissertation also discusses some problems of QoS forecast, such as determination of parameters, solution of non-uniform time interval, active intervention. The results of experiment in running system indicate that the forecast method is valid.Because the functions and resources of web service based system are separated and loosely coupled, the traditional access control models are difficult to deal with such situation. In this dissertation, after analyzing security requirements of web service based system, an attributed based double access control model (ABDAC) is presented to achieve access control of functions and resources in the web service based system. The dissertation proposes access control policy and attributes-privileges mapping algorithms of ABDAC, and discusses consistency and integrity of ABDAC. Moreover, XACMLis used to realize an application of ABDAC and test the impact to system performance.At last, the dissertation introduces web service architecture with QoS and security extended, and then we implement two sub-systems of software infrastructure to SBA: Hall for Workshop of Metasynthetic Engineering and Product Data Management System. These two sub-systems have been applied in projects of complex product acquisition.