Each of electronic devices, such as smartphones or tablet computers, may perform a variety of functions such as wireless communication functions and media output functions. The electronic device may use various communication manners for transmitting and receiving data with peripheral external devices while performing the functions. For example, the electronic device may transmit data about an output image to a peripheral display device (e.g., a TV and a monitor) using mirroring technologies. The display device may output the same image as an image output a screen of the electronic device in real time (or within a predetermined time difference).
The electronic device may transmit data to an external device using wireless-fidelity (Wi-Fi) communication. The Wi-Fi direct communication may be a communication method of directly and wirelessly connecting the electronic device to the external device and communicating data, not a communication method of communicating with another device through a separate communication network such as the Internet. Wi-Fi display (WFD) or Miracast of the Wi-Fi direct communication may be technologies in which the electronic device sends data to the external device to output the same screen on the external device. If the electronic device connects to the external device in a Miracast manner, screen information of the electronic device may be streamed on the external device through a real-time transport protocol (RTP). To output a screen on the external device in the Miracast manner, a search procedure of the external device should be previously performed.
FIG. 1 is a signal sequence diagram of a process that is known in the art.
Referring to FIG. 1, to establish a WFD connection, an electronic device 101 may connect with a network using tunneled direct link setup (TDLS). The TDLS may be network communication technologies for providing support to share data without the necessity of a separate medium for an inter-device network. The electronic device 101 may connect to an external device 102 through a communication connection of a layer 2 (L2) in an open system interconnection (OSI) 7 layer.
In operation 110, the electronic device 101 may broadcast a tunnel probe request based on an L2 frame to an AP 103. The request may include a WFD information element (IE), a basic service set identification (BSSID) (e.g., a medium access control (MAC) address) of the AP 103, an IP address of the electronic device 101, and the like.
In operation 120, the AP 103 may broadcast the request to the external device 102.
If receiving the request, in operation 130, the external device 102 may transmit a tunnel probe response to the AP 102. The tunnel probe response may be transmitted in a unicast manner.
In operation 140, the AP 103 may transmit the tunnel probe response to the electronic device 101.
The above-mentioned device searching method according to the related art is performed according to the L2 frame. Therefore, it is necessary to encapsulate or parse the request or response. If a peripheral is changed, it is necessary to correct a hardware chip (e.g., a Wi-Fi driver).