A communication network, such as a mobile IP network, includes at least one mobile terminal and a plurality of home agents adapted to provide, within working sessions, communication services to the above mobile terminal. An electromagnetic switch element that is activated by displacement of conducting elements, the displacement being forced through electrostatic, electric field, magnetic field, thermal or other means. According to one aspect of the invention, the piezoelectric device can be formed from lead zirconate titanate. The signal paths each use identical filter parts.