RES156 – 247 – 3 that the notifying administration for the satellite network within which the earth stations in motion operate by means of fixed, mobile or transportable terminals shall ensure that they have the capability to limit operations of such earth stations to the territory or territories of administrations having authorized those earth stations and to comply with Article 18; 4 that administrations authorizing earth stations in motion shall require the operators to provide a point of contact for the purpose of tracing any suspected cases of interference from earth stations in motion.