In both the Intranet and the Internet environments, access to services is usually based on a Client-Server model. In this scenario the server's role is a critical one as any malfunctioning will jeopardize the functioning of the system as a whole and in some cases may totally prevent access to services that are of vital importance for the normal working activities.Traditional servers offer little support to handle situations like these. Intervention is normally in the form of duplication of services on several mirror servers which start to function when the main server crashes.Our work comes into this scenario. The solution we propose consists of organizing a pool of hosts in a single logical entity, called a Virtual Service Provider (VSP), addressed by client using a unique IP address. The system exploits the mobile agent technology provided by the Mobile Agent Platform (MAP) implemented in Java.