Stations send RTS/CTS packets before sending data packets

RTS/CTS packets are represented by one circle. Data packets are represented by two circles. Data packets move slower than RTS/CTS packets. First, A wants to send a data packet to B, so it broadcasts a RTS packet. When B receives the RTS packet from A, it replies with a CTS packet. At the same time, C sends a RTS packet to B. B however, doesn't reply to C because it is waiting for the data packet from A. So, C waits. The waiting time is calculated using the exponential backoff function. After B has received the packet from A, C sends a RTS packet again. This time, B replies because it is ready to receive the data packet from C. No collision occurred due to the RTS/CTS packets.