A network device, comprising: • a sending module , configured to send a radio resource control, RRC, downlink message to a user equipment, UE; • a processing module , configured to preallocate, within a time range of a radio resource control procedure delay, RRC procedure delay, of the RRC downlink message, an uplink grant of an RRC uplink response message corresponding to the RRC downlink message, wherein • the sending module is further configured to send the uplink grant within the time range of the RRC procedure delay to the UE; and • a receiving module , configured to: ∘ receive, on an uplink resource indicated by the uplink grant, the RRC uplink response message on an RRC layer from the UE, ∘ receive an acknowledgement of the RRC downlink message from the UE, • wherein: ∘ a sending time of the uplink grant is later than a sending time of the RRC downlink message and the sending time of the uplink grant is not later than a receiving time of the acknowledgement message of the RRC downlink message, ∘ when the RRC downlink message is sent in a transparent transmission mode, TM, the acknowledgement message of the RRC downlink message is a feedback message at a Medium Access Control, MAC, layer; ∘ when the RRC downlink message is sent in an acknowledged mode, AM, the acknowledgement message of the RRC downlink message is a feedback message at a Radio Link Control, RLC, layer. • a sending module , configured to send a radio resource control, RRC, downlink message to a user equipment, UE; • a processing module , configured to preallocate, within a time range of a radio resource control procedure delay, RRC procedure delay, of the RRC downlink message, an uplink grant of an RRC uplink response message corresponding to the RRC downlink message, wherein • the sending module is further configured to send the uplink grant within the time range of the RRC procedure delay to the UE; and • a receiving module , configured to: ∘ receive, on an uplink resource indicated by the uplink grant, the RRC uplink response message on an RRC layer from the UE, ∘ receive an acknowledgement of the RRC downlink message from the UE, ∘ receive, on an uplink resource indicated by the uplink grant, the RRC uplink response message on an RRC layer from the UE, ∘ receive an acknowledgement of the RRC downlink message from the UE, • wherein: ∘ a sending time of the uplink grant is later than a sending time of the RRC downlink message and the sending time of the uplink grant is not later than a receiving time of the acknowledgement message of the RRC downlink message, ∘ when the RRC downlink message is sent in a transparent transmission mode, TM, the acknowledgement message of the RRC downlink message is a feedback message at a Medium Access Control, MAC, layer; ∘ when the RRC downlink message is sent in an acknowledged mode, AM, the acknowledgement message of the RRC downlink message is a feedback message at a Radio Link Control, RLC, layer. ∘ a sending time of the uplink grant is later than a sending time of the RRC downlink message and the sending time of the uplink grant is not later than a receiving time of the acknowledgement message of the RRC downlink message, ∘ when the RRC downlink message is sent in a transparent transmission mode, TM, the acknowledgement message of the RRC downlink message is a feedback message at a Medium Access Control, MAC, layer; ∘ when the RRC downlink message is sent in an acknowledged mode, AM, the acknowledgement message of the RRC downlink message is a feedback message at a Radio Link Control, RLC, layer. <EOS>