Ethernet: The Definitive Guide

Chapter 17. Ethernet Repeater Hubs

A repeater is a device that allows you to build multi-segment half-duplex Ethernet systems. Repeaters do this by linking the segments together, making the whole system function as though it were a single large segment. Individual half-duplex media segments are of limited length to ensure acceptable signal timing and signal quality for the entire length of the segment. When linking segments together, repeaters act upon the Ethernet signals, regenerating the signal and restoring the timing. This ensures that each frame makes it through the entire Ethernet system intact, and that every station in the Ethernet system will receive the frame correctly. The configuration guidelines that apply to all types of half-duplex systems are described in Chapter 13.

Repeaters have been widely used to build extended Ethernet systems for years. However, many network designs today are based on switching hubs to take advantage of the extra bandwidth and other capabilities that switching hubs can provide. The cost of switching hubs has rapidly decreased in recent years, and therefore many network designers use switching hubs instead of repeaters for all new network installations and for upgrades from older systems. Switching hubs are described in Chapter 18.

A repeater is intended to provide a simple and inexpensive way to link two or more network segments. By using repeaters, you can build large half-duplex Ethernet systems that can span the maximum distance allowed ...