A standby control method performed by a terminal, wherein the terminal comprises a first communications module and a second communications module, and wherein the method comprises: after a standby instruction is received by the terminal, sending first notification information to a relay device through a first communication link, wherein the first communication link is a communication link between the first communications module and the relay device, and the first notification information is used to instruct the relay device to serve as a proxy for the terminal to send a first keep-alive packet to a cloud server to inform the cloud server that the terminal is online; and, disabling the first communication link and a main control central processing unit, CPU of the terminal, characterised in that the method comprises: receiving a second keep-alive packet sent by the relay device through a second communication link, and returning acknowledgement information of the second keep-alive packet to inform the relay device that the terminal is online, wherein the second communication link is a communication link between the second communications module and the relay device, and wherein a communication rate of the second communication link is lower than a communication rate of the first communication link, and a number of bytes occupied by the acknowledgement information of the second keep-alive packet is less than a number of bytes occupied by the second keep-alive packet. after a standby instruction is received by the terminal, sending first notification information to a relay device through a first communication link, wherein the first communication link is a communication link between the first communications module and the relay device, and the first notification information is used to instruct the relay device to serve as a proxy for the terminal to send a first keep-alive packet to a cloud server to inform the cloud server that the terminal is online; and, disabling the first communication link and a main control central processing unit, CPU of the terminal, characterised in that the method comprises: receiving a second keep-alive packet sent by the relay device through a second communication link, and returning acknowledgement information of the second keep-alive packet to inform the relay device that the terminal is online, wherein the second communication link is a communication link between the second communications module and the relay device, and wherein a communication rate of the second communication link is lower than a communication rate of the first communication link, and a number of bytes occupied by the acknowledgement information of the second keep-alive packet is less than a number of bytes occupied by the second keep-alive packet. receiving a second keep-alive packet sent by the relay device through a second communication link, and returning acknowledgement information of the second keep-alive packet to inform the relay device that the terminal is online, wherein the second communication link is a communication link between the second communications module and the relay device, and wherein a communication rate of the second communication link is lower than a communication rate of the first communication link, and a number of bytes occupied by the acknowledgement information of the second keep-alive packet is less than a number of bytes occupied by the second keep-alive packet.