Research Of Migrating B/S Architecture Legacy Systems To The RIA/SOA

Over the last four decades IT systems have grown exponentially, leaving companies to handle increasingly complex software architectures. With business continuity, these systems need to be updated to meet the new business requirement. Also, it is important to improve the customers'experience of applications. At the same time, new IT solutions are emerged quickly to meet the business'requirement. Service Oriented Architecture (SOA) is developed to help enterprise to build "on demand" information system; Rich internet Application (RIA) is adopted to improve the user experience of web application. RIA combines the advantages of desktop application and browser based application.Seeing that SOA is the trend of backend organization and RIA is the trend of front-end, IT executives combine the RIA GUIs with SOA-empowered middleware to offer new enterprise service architecture. Thus, enterprise applications architecture is moved from client-server (C/S), to browser-server (B/S), and now RIA/SOA.As a result of architecture evolution, more and more applications are moved to RIA/SOA architecture. Currently, more than 90% of the internet applications are based on B/S architectures. This brings our research to on migration process model and methodology to help IT executives to migration from B/S to RIA/SOA.In this paper, a reference model on the process of migrating B/S applications to RIA/SOA architecture is introduced. This model is mainly consisted of four steps: 1,extract presentation logic; 2,extract SOA services; 3,choreograph SOA services and make a Facade for RIA client; 4,rebuild the RIA client. For every step in the model, migration strategies are presented. In the third step, "design by contract" is introduced to strengthen the Facade definition to contract between client and server. Further, a way to check the compliance of contacts is also presented here. Another focus of this paper is the migration solutions. We presented our innovative solutions in this paper. Choreographing the services in both client and server, moving the server side session in B/S to RIA client, adding local file system support into the new RIA client are presented in this paper.At last, these methodologies and process model are applied on a real project:migrate a B/S based data dissemination application to RIA/SOA architecture for a finance company. The project is in production now. The customers are satisfied with the improved user experience and performance and flexibility.