If we can attend the LAN then why we need a WAN?

Answer 1

We can extend LAN by using repeaters. If we increase LAN by using large number of repeaters than this arrangement does not guarantees sufficient signal strength. Each repeater and segment along the path increases the delay. If the delay becomes too large scheme fails. In fact, repeaters are part of the Ethernet standard, which specifies that the network will not operate correctly if more than four repeaters separate any pair of stations. i. If we can extend the LAN then why we need a WAN? ii. How can a bridge know whether to forward frames? iii. Can the length of an Ethernet be increased to many segments of 500 meter each merely by adding a repeater to connect each additional segment? iv. How can a computer attach to a network that sends and receives bits faster than the computer's CPU can handle them?