The present application relates to a user equipment, a base station, a core network and a method for data transmission. The user equipment transmits capability information to the core network for indicating to the core network at least one downlink data transmission procedure supported by the user equipment. The core network transmits a first paging message to the base station. The base station transmits a second paging message to the user equipment. The user equipment selects a downlink data transmission procedure from the at least one downlink data transmission procedure after receiving the second paging message.