A Pattern-Based Design Approach for Subscription Management of Software as a Service

Software as a Service (SaaS) is essentially about delivering a software application as a service over the Web with a usage-based charging plan. Existing Web service subscription models do not consider the complexity of the application and the business environment; for example, multiple service elements with mutual dependencies derived from one application, or various business partnership models for reselling and cross-selling services. Therefore the design of subscription management is critical for a SaaS provider to appropriately decompose its application into service elements and then package them into service offerings for a client or business partner to subscribe according to the nature of the application and the overall business design. In this paper, we propose a pattern-based approach for the subscription management design of SaaS. A subscription model is introduced first to capture the different entities and their relationships involved in SaaS subscription. Then a method supported with service structure patterns and business interaction patterns analysis is presented to empower a SaaS provider to design an appropriate subscription model for its service offering. A case study is made to demonstrate the effectiveness of the method at the end of this paper.