In the Cloud Computing Context, a virtual Machine (VM) can be migrated from one physical host to a remote physical host while keeping it's address to avoid service discontinuity. The service application is so no more hosted on a particular physical machine but can move from one to other. We define therefore a new mobility context where the services provided by VMs move from one location to another during the continuous execution of the service application. This mobility requires the establishment of Layer-2 pipes to ensure that the VMs keep their initial addresses. We propose SMVN (Service Mobility Virtual Network), an MPLS/VPLS virtual network for the seamless VMs mobility. We state a MILP formulation of the proposed problem and solve it optimally using the TOMLAB/CPLEX solver. To deal with the latency constraints of VMs mobility, we propose also a Multi-Weighted Pareto Heuristic (MWPH) to solve the SMVN problem.