E-Services

Mobile devices allow users to access information resources and services over many different distribution channels – anywhere, anytime, anyhow. Technical and usage characteristics of mobile systems are highly variable with respect to user capabilities and context characteristics. Therefore an immense level of flexibility is required. This book presents a framework for mobile information systems, focusing on quality of service and adaptability at all architectural levels. These levels range from adaptive applications to e-services, middleware, and infrastructural elements, as developed in the "Multichannel Adaptive Information Systems" (MAIS) project. The design models, methods, and tools developed in the project allow the realization of adaptive mobile information systems in a variety of different architectures. In particular, this chapter introduces the E-service model on which the adaptive information systems are based