A communication system including a terminal, a base station of a first public land mobile network, PLMN, a mobility management entity, MME, and a home subscriber server, HSS, the communication system comprising: the terminal configured to transmit, to the base station a measurement report; the base station configured to: transmit, to the MME, a closed subscriber group, CSG, identity, ID, related to a target cell of a second PLMN for a handover of the terminal, and transmit, to the terminal, a handover command related to the target cell; and the MME configured to: transmit, to the HSS, a request message, the request message comprising the equivalent PLMN list in case that the MME supports inter-PLMN handover to a CSG cell in the equivalent PLMN list, receive (401.b), from the HSS, closed subscriber group, CSG, subscription information for an equivalent PLMN list in response to the request message, validate a CSG membership of the terminal in the target cell for the handover based on the CSG ID related to the target cell of the second PLMN and the CSG subscription information for the equivalent PLMN list related to the terminal. the terminal configured to transmit, to the base station a measurement report; the base station configured to: transmit, to the MME, a closed subscriber group, CSG, identity, ID, related to a target cell of a second PLMN for a handover of the terminal, and transmit, to the terminal, a handover command related to the target cell; and the MME configured to: transmit, to the HSS, a request message, the request message comprising the equivalent PLMN list in case that the MME supports inter-PLMN handover to a CSG cell in the equivalent PLMN list, receive (401.b), from the HSS, closed subscriber group, CSG, subscription information for an equivalent PLMN list in response to the request message, validate a CSG membership of the terminal in the target cell for the handover based on the CSG ID related to the target cell of the second PLMN and the CSG subscription information for the equivalent PLMN list related to the terminal. transmit, to the MME, a closed subscriber group, CSG, identity, ID, related to a target cell of a second PLMN for a handover of the terminal, and transmit, to the terminal, a handover command related to the target cell; and the MME configured to: transmit, to the HSS, a request message, the request message comprising the equivalent PLMN list in case that the MME supports inter-PLMN handover to a CSG cell in the equivalent PLMN list, receive (401.b), from the HSS, closed subscriber group, CSG, subscription information for an equivalent PLMN list in response to the request message, validate a CSG membership of the terminal in the target cell for the handover based on the CSG ID related to the target cell of the second PLMN and the CSG subscription information for the equivalent PLMN list related to the terminal. transmit, to the HSS, a request message, the request message comprising the equivalent PLMN list in case that the MME supports inter-PLMN handover to a CSG cell in the equivalent PLMN list, receive (401.b), from the HSS, closed subscriber group, CSG, subscription information for an equivalent PLMN list in response to the request message, validate a CSG membership of the terminal in the target cell for the handover based on the CSG ID related to the target cell of the second PLMN and the CSG subscription information for the equivalent PLMN list related to the terminal.