A communication control method, and network apparatus includes receiving a PLMN identifier and a first identifier from a first user terminal, where the first identifier is included in a discovery signal which the first user terminal has received from a second user terminal, determining, in response to receiving the first identifier, whether the first identifier is an identifier allocated in the first PLMN. In response to a determination that the first identifier is not the identifier allocated in the first PLMN, sending the first identifier to a second network apparatus belonging to a second PLMN, and receiving the information of an application used by the second user terminal, from the second network apparatus. In response to the controller determining that the first identifier is the identifier allocated in the first PLMN, transmitting, to the first user terminal, information of the application used by the second user terminal.