The Need for a Two-Lane (Network) Road

The Need for a Two-Lane (Network) Road

In Figure 4-3, PC2 sends an electrical signal to PC1. As it turns out, if PC1 tried to send some electricity to PC2 at the same time, over the same wire, the electrical signals would overlap, and neither PC1 nor PC2 could understand what was sent.

To solve the problem, PC1 and PC2 need to use two wiresone for PC1 to send bits to PC2, and one for PC2 to send to PC1. Figure 4-4 shows two wires, with PC1 and PC2 sending and receiving at the same time.