frames are generated at node A and sent to node C through node B. Determine the minimum data rate required between nodes B and C so that the buffers of node B are not flooded, based on the following:

• The data rate between A and B is 100 kbps.

• The propagation delay is 5 ms/km for both lines.

• There are full-duplex lines between the nodes.

• All data frames are 1000 bits long; ACK frames are separate frames of negligible length.

• Between A and B, a sliding-window protocol with a window size of 3 is used.

• Between B and C, stop-and-wait is used.

• There are no errors.

Hint: In order not to flood the buffers of B, the average number of frames entering and leaving B must be the same over a long interval.