Ethernet Video Series

Episode 03, Segment 04 of 04

Ethernet Cables (continued)


At this point it’s time to think back to our original Ethernet tutorial, the one in which we compared an old-style Ethernet to a rope stretched tight between two springs. You may be wondering, as you think about that, “Why do these new Ethernet cables need 8 wires?” A good question.

Well, some of the wires are actually unused. But an extra pair of wires is used in the most modern versions of Ethernet with these cables in order to accomplish two conversations simultaneously in both directions. Obviously, these wires have two stations, one at each end. With two pairs of wires, each can transmit to the other at the same time in a point-to-point fashion, without collisions. This is called, “full duplex.” Some hubs, and some routers and some switches support full duplex, and some do not. But the most modern of these kinds of this equipment also automatically negotiate that capability. So you don’t need to worry about it as a general rule. And these modern cat5 cables are compatible with all of those options.

End of Episode 03. Continue with Episode 4:

Episode 04, Segment 1 of  3