Automatic Repeat reQuest (ARQ)

Automatic Repeat reQuest (ARQ) is a protocol used in data communication to ensure reliable transmission of information. When data is sent, it is expected to arrive correctly at its destination. If the receiver detects an error or doesn't receive the data at all, it sends a request back to the sender to resend the missing or erroneous data. This process continues until the data is received correctly. ARQ helps maintain the integrity of data transfer over networks, making it essential for applications where accuracy is critical, such as in file downloads, online communications, and video streaming.