An electronic device (101, 310) comprising: a wireless communication module; a processor operatively connected to the wireless communication module; and a memory operatively connected to the processor, wherein the memory stores instructions causing, when executed, the processor to: perform (301, 601) a negotiation procedure for Internet protocol multimedia subsystem, IMS, session establishment for a multimedia service with audio-visual profile feedback, AVPF,-off with a counterpart electronic (102, 104, 320) device by using the wireless communication module; when the negotiation procedure is performed with AVPF-off, after the IMS session is established, include, in a first packet, a string-based first message indicating a quality improvement function supported by the electronic device, and transmit (303, 603) the first packet to the counterpart electronic device (102, 104, 320), the first packet being continuously transmitted while the multimedia service is being performed; receive a second packet including a string-based second message indicating a quality improvement function supported by the counterpart electronic device (102, 104, 320); analyze an identifier of the second message by parsing the second message of the received second packet; if the identifier of the second message belongs to a recognizable identifier, determine (307, 605) that the counterpart electronic device (102, 104, 320) is a device available for the multimedia service based on the quality improvement function; compare first function information of the first message with second function information of the second message based on the identifier; enable (311, 607) at least one quality improvement function supported concurrently between the electronic devices regardless of the negotiation by AVPF-off; and while the multimedia service is being performed, transmit (315, 609) a packet having an improved quality to the counterpart electronic device (102, 104, 320) on the basis of the quality improvement function. a wireless communication module; a processor operatively connected to the wireless communication module; and a memory operatively connected to the processor, wherein the memory stores instructions causing, when executed, the processor to: perform (301, 601) a negotiation procedure for Internet protocol multimedia subsystem, IMS, session establishment for a multimedia service with audio-visual profile feedback, AVPF,-off with a counterpart electronic (102, 104, 320) device by using the wireless communication module; when the negotiation procedure is performed with AVPF-off, after the IMS session is established, include, in a first packet, a string-based first message indicating a quality improvement function supported by the electronic device, and transmit (303, 603) the first packet to the counterpart electronic device (102, 104, 320), the first packet being continuously transmitted while the multimedia service is being performed; receive a second packet including a string-based second message indicating a quality improvement function supported by the counterpart electronic device (102, 104, 320); analyze an identifier of the second message by parsing the second message of the received second packet; if the identifier of the second message belongs to a recognizable identifier, determine (307, 605) that the counterpart electronic device (102, 104, 320) is a device available for the multimedia service based on the quality improvement function; compare first function information of the first message with second function information of the second message based on the identifier; enable (311, 607) at least one quality improvement function supported concurrently between the electronic devices regardless of the negotiation by AVPF-off; and while the multimedia service is being performed, transmit (315, 609) a packet having an improved quality to the counterpart electronic device (102, 104, 320) on the basis of the quality improvement function. perform (301, 601) a negotiation procedure for Internet protocol multimedia subsystem, IMS, session establishment for a multimedia service with audio-visual profile feedback, AVPF,-off with a counterpart electronic (102, 104, 320) device by using the wireless communication module; when the negotiation procedure is performed with AVPF-off, after the IMS session is established, include, in a first packet, a string-based first message indicating a quality improvement function supported by the electronic device, and transmit (303, 603) the first packet to the counterpart electronic device (102, 104, 320), the first packet being continuously transmitted while the multimedia service is being performed; receive a second packet including a string-based second message indicating a quality improvement function supported by the counterpart electronic device (102, 104, 320); analyze an identifier of the second message by parsing the second message of the received second packet; if the identifier of the second message belongs to a recognizable identifier, determine (307, 605) that the counterpart electronic device (102, 104, 320) is a device available for the multimedia service based on the quality improvement function; compare first function information of the first message with second function information of the second message based on the identifier; enable (311, 607) at least one quality improvement function supported concurrently between the electronic devices regardless of the negotiation by AVPF-off; and while the multimedia service is being performed, transmit (315, 609) a packet having an improved quality to the counterpart electronic device (102, 104, 320) on the basis of the quality improvement function.