A base station according to a first aspect includes a controller configured to perform a process of receiving, from a mobility management apparatus, a paging message used for paging of a radio terminal. The paging message includes a first field for idle mode non-extended DRX and a second field for idle mode extended DRX. If information indicating a DRX cycle of the idle mode extended DRX is included in the second field, the controller is configured to determine that the idle mode extended DRX is configured to the radio terminal.