Pervasive computing applications allow users to access information from anywhere while traveling and using variety of devices. Heterogeneity and limitation of resources involved in this application demand adaptation of content according to the current context (device, user, network etc.). The dynamic nature of adaptation mechanisms together with emerging opportunities of Web Service technology provides new approach of adaptation which is service-based. While this approach would provide a valuable service for the end customer, the service provider, and the content provider, it is important to have an architectural framework which is simple, scalable, flexible and interoperable. Moreover, in order to provide a complete service-based content negotiation and adaptation solution, we must have a model, or a tool, that allows defining environmental constraints, mapping them to appropriate adaptation service requirements and finding an optimal service configuration. In this paper, we present ...