There are currently several impediments delaying the rapid introduction of Active Networks. A basic one is the impossibility of updating Internet overnight, even the access nodes only, to support active network applications. The deployment of active networks will be gradual, beginning with only few active nodes. However, the provision of active services requires that the traffic visits active nodes. Clearly, a ubiquitous service cannot be provided with just a few active nodes and current Internet routing. That is, with the routing used to cater for fixed hosts. In case of mobile hosts using Mobile IP, there is a way to circumvent the need to update a substantial amount of Internet routers, and still to offer omnipresent active services. When Mobile IP is seen as a fundamental capability of almost every future end-user host, and that the users most certainly appreciate the mobility support, and that the active services are most suited for mobile environment, we can draw the following conclusion: An active network “overlay” based on Mobile IP routing is both reflecting user needs and suited to remove the need for extensive updating of Internet nodes prior active network service provision. This paper presents a viable architecture for a Mobile IP based active network overlay, capable of dynamically assigning suitably located active nodes to cater for traffic sources involved in a particular session. The design and implementation of the proposed architecture will be carried out in Eurescom project P926 (Caspian).