Flexible and adaptive services in pervasive computing

Availability of services to users and applications is a critical issue in mobile and pervasive computing environments replete with hundreds and thousands of smart devices. In such environments, devices such as sensors, embedded processors, personal servers, cell phones and PDAs have limited resources in terms of CPU, memory, communication bandwidth, and battery energy. Therefore, it is extremely important as well as challenging to conserve device resources while providing software services in a timely fashion for a variety of application scenarios. The solution lies in the deployment of software services in pervasive computing environments that can be used by mobile and wireless clients on resource-constrained devices. In this chapter we discuss issues in providing services in pervasive environments and give a summary of related work. Furthermore, we propose a service provisioning framework that is not only flexible in defining and generating services, but also adaptive to the environment. The service provisioning mechanism based on the community computing framework captures the essence of devices and services around users, and facilitates the creation and composition of flexible and adaptive services. We develop an elegant Petri net based modeling of the framework and present several case studies to demonstrate and validate the model. © 2005 Elsevier Inc. All rights reserved.