Pervasive services vs. Web services: Survey and comparison

After the vision of Mark Wieser, and the advent of 3G connection with a large number of mobile computing devices(PDAs, Smartphones, Tablet, etc.) that have democratized access to information anywhere, we live in a new era of ubiquity where a set of services are offered in our environments. In this work we try to review the conception, discovery and composition of these services called pervasive in a comparison with web services that have a great popularity in the conception of information systems. This comparison will allow us to clarify the points of similarity and dissimilarity between the pervasive services and web services in order to reduce the gap between them.