Research On Key Technologies Of Service-Oriented Computing

With the development of Internet, more and more software technologies are needed to research. Enterprise applications should respond rapidly to change, to integration and reorganization of the way to adapt to the new business mode. The development of the software engineering has played a strong role in promoting this. The traditional software business mode, namely, the sale of software License is difficult to meet future demand. Center for the products to the Internet customer-centric paradigm shift triggered a next-generation software business model, that is, on-demand service model. The software business model has been the industrial and the academia is highly valued. But the traditional computing paradigm is relatively static, closed computing environment, and can not match the new challenges.Service-oriented computing (Service Oriented Computing, SOC) is becoming the next generation of computing paradigm. SOC use of a service as basic structural units, distributed application support the rapid, low-cost modular development. Web services (Web Services) is the most promising technologies to realize SOC. Web services have lots of advantages, such as the use of XML language to describe service interfaces and service calls, using Internet standards such as HTTP communication protocol transmission. The above good features enable SOC the key core technologies to solve on-demand service. In an on demand business, process should be transparent to users, users do not care about the background of logic is how to organize, how to implement, and the only requirement is automatically get the correct and efficient solution. At present, there are many key technical problems constraining the process automatically, efficiently solved. Automatic and efficient business processes is very important for application logic provider. If not provide effective mechanism, may result in services that fail to meet anticipated demand, which eventually led to declining customer satisfaction. Especially in the military, financial, medical and other high performance requirements of the application scenes, if not efficient completion of user needs will cause incalculable losses. Therefore, the study of automatic and efficient service technology is very important to academic and industrial. In this paper, we do some research on the area of automatic and high performance service-oriented computing.First, in the service selection stage, Multi-QoS constrained Web services selection is a NP hard problem and its difficulty lies in the huge solution space. The NP hard problem can not be solved in polynomial time, which results in a combination of multi-service QoS constraints can not choose the time of the urgent application in use. In this paper, we propose a high performance approach for multi-QoS constrained Web Services composition. The correlations of all the candidate services are collected to construct a constrained model, which can reduce the search space efficiently. By using the constrained model, a heuristic algorithm is proposed to find the feasible solution with high performance and high precision. We performed experiments to evaluate the validity and efficiency of the model. The results show that the same level of success ratio, our approach can achieve a lower level of computational complexity. In addition, the existing single service discovery methods have lots of problems and could not be executed automatically. In this paper, based on the gene sequence of services matching algorithm, as well as active semantic extraction technology, we proposed a novel service selection approach to support semantic level match.Secondly, in the client generation stage, Message Exchange Pattern (MEP) is a challenging problem in the interaction of Web services. However, it is difficult to enact the MEPs automatically, which means the Web services infrastructure has to hard-code the support for various MEPs and it is also difficult to extend. In this paper, we propose an automatic enactment of MEPs for Web services. The enactment consists of two parts. The first part is the formal description method for MEPs, which is used to define MEP accurately with no ambiguities. The second part is the automatic enactment framework, which will automatically enact a new MEP through a MEP process machine that is generated according to the MEP definition. New MEPs would become easy to be engaged in Web services.Finally, in the service logic executed phase. SOAP, based on Extensible Markup Language (XML), inherits not only the advantages of XML, but its relatively poor performance. This makes SOAP a poor choice for many high-performance web services. In this paper, we propose a new approach to improve Web services performance. Focusing on avoiding traditional XML parsing and Java reflection at runtime, we create a service-specific SOAP processor to accelerate execution. Through our experiments in this paper, we observed that our approach obtained about a treble performance gain (maximum) by incorporating the SOAP processor into the Axis SOAP engine. In addition with the rapid development of Web Services, providing quality of service (QoS) becomes a key factor to achieve success in business. At present, a lot of enterprises systems do not provide QoS-Enabled Web Services. However, modifying the implementation of those systems to satisfy the requirements of consumers is exorbitant. To solve this problem, this paper proposed a dynamic QoS guarantee approach, which can provide a flexible mechanism for managing and deploying QoS handler, and makes legacy systems provide QoS On-Demand Web Service to consumers without changing the implementation.