Although flow control was briefly described earlier, this section contains more detail.
Flow control
is responsible for ensuring that the transmitting station does not send data faster than the
receiving station can process it. This is done by establishing a window size for the transmission.
Look at Figure 36.6 to see how windowing works. Notice that the originating system sends
out a specified number of PDUs. Once that number is reached, the originating system waits for
a response from the destination system. After the response is received, the system continues to
transmit data.