Disclosed are a terminal, an operating method thereof, and a computer-readable recording medium. The operating method includes establishing a video call session between a first terminal and a second terminal, receiving, by the second terminal, data obtained by the first terminal, sequentially storing, by the second terminal, the data received from the first terminal in a buffer size, performing, by the second terminal, a validity check on the data stored in the buffer, and processing, by the second terminal, the data in response to a result of the validity check.