Techniques for Dynamic Adaptation of Mobile Services

Abstract

This chapter discusses the dynamic adaptation of software for mobile computing. The primary focus of the chapter is to discuss a number of techniques for adapting software as it runs, and managing the application of those adaptations. In a mobile computing environment the need for adaptation can often arise as a result of a spontaneous change in the context of the operating environment, ancillary software, or indeed the user. To exacerbate this problem, if that contextual change is in some way unanticipated, then the required adaptation may be itself unanticipated until the need for it arises. For this reason, this chapter is particularly concerned with supporting adaptations that are ?completely unanticipated?` [19]. The chapter discusses reflective and aspect-oriented techniques for dynamically adapting software for mobile computing. Policy-based management is then discussed as a mechanism to control such dynamic adaptation mechanisms. The chapter then introduces the Chisel dynamic adaptation framework, which supports completely unanticipated dynamic adaptation, and discusses a case study whereby Chisel is used with ALICE, a mobile middleware, to provide a flexible and adaptable middleware framework for mobile computing.