An information transmission method by a terminal, the method comprising: receiving, from a base station, minimization of drive test, MDT, configuration information in radio resource control, RRC, connected mode, the MDT configuration information including duration information related to the MDT; transmitting, to the base station, MDT available information via a radio resource control, RRC, connection setup complete message, if the terminal has an available MDT measurement information generated based on the MDT configuration information, the MDT available information indicating that the terminal has the available MDT measurement information the method being characterized by further comprising: receiving, from the base station, a request message comprising a request for radio link failure, RLF, information and random access channel, RACH, information; and transmitting, to the base station, a response message including the RLF information and the RACH information according to the request message, wherein the response message is transmitted via a signaling radio bearer 2, SRB2, if the request message includes a request for the MDT measurement information and the MDT measurement information is presented in the response message, and wherein the response message is transmitted via a signaling radio bearer 1, SRB1, if the request message does not include the request for the MDT measurement information and the MDT measurement information is not presented in the response message. receiving, from a base station, minimization of drive test, MDT, configuration information in radio resource control, RRC, connected mode, the MDT configuration information including duration information related to the MDT; transmitting, to the base station, MDT available information via a radio resource control, RRC, connection setup complete message, if the terminal has an available MDT measurement information generated based on the MDT configuration information, the MDT available information indicating that the terminal has the available MDT measurement information the method being characterized by further comprising: receiving, from the base station, a request message comprising a request for radio link failure, RLF, information and random access channel, RACH, information; and transmitting, to the base station, a response message including the RLF information and the RACH information according to the request message, wherein the response message is transmitted via a signaling radio bearer 2, SRB2, if the request message includes a request for the MDT measurement information and the MDT measurement information is presented in the response message, and wherein the response message is transmitted via a signaling radio bearer 1, SRB1, if the request message does not include the request for the MDT measurement information and the MDT measurement information is not presented in the response message. receiving, from the base station, a request message comprising a request for radio link failure, RLF, information and random access channel, RACH, information; and transmitting, to the base station, a response message including the RLF information and the RACH information according to the request message, wherein the response message is transmitted via a signaling radio bearer 2, SRB2, if the request message includes a request for the MDT measurement information and the MDT measurement information is presented in the response message, and wherein the response message is transmitted via a signaling radio bearer 1, SRB1, if the request message does not include the request for the MDT measurement information and the MDT measurement information is not presented in the response message.