The tighter and tighter converging integration of fixed and mobile telecommunication networks along with the telecom-IP network convergence have opened up the enormous market potential for a rich ecosystem of Next-Generation (NG) converged network technologies and services. Such NG services are envisioned to have the capability of seamlessly exploiting all the population of Web applications already available in the IP network and at the same time of leveraging the legacy capabilities and functions of typically proprietary and less open telecommunication networks. To some extent, the evolution trend is similar to what is happening for pervasive and ubiquitous services in all IP-based mobile computing. Since device miniaturization and wireless communications are making more and more feasible mobility-enhanced services to exploit all potential and opportunities of mobile computing, the goal of the mobility scenarios is becoming the realization of easily and automatically integrated services, towards the ultimate objective of disappearing computing, i.e., the seamless and transparent collaboration of wireless devices to most human activities without the need of explicit user/administration intervention.