Functionality adaptation: a context-aware service code adaptation for pervasive computing environments

Pervasive computing has attracted a lot of attention in recent years. There are now proxy servers that are specially designed for pervasive computing. To enable content viewing in small devices, different kinds of content adaptation techniques have been used (such as distillation and transcoding) to adapt Web contents in content-rich servers to resource-constrained devices. Adaptation of Web contents has been widely discussed, but little attention was paid to the adaptation of services (or service code), which is equally important for computing anytime, anywhere, and on any device. We present an approach to adaptation of service code which is proxy-based and context-aware, called "functionality adaptation". The main difficulty of such an adaptation is to estimate the resource usage required for an execution, which varies with the input size and is available only at run-time. We propose a conservative solution. A simple prototype has been implemented to evaluate our adaptation approach.