Network+

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Be sure to match or exceed the rating for existing cabling. Using a Category 3 patch panel with Category 5 cabling makes the network a Category 3 network.

The Repeater


As we discussed in Chapter 2, “The OSI Model,” a repeater amplifies (or repeats) network signals to extend the maximum reach of a network. Repeaters receive network signals on one port, amplify them, and repeat them out on the other port. Since they operate only at the Physical layer of the OSI model, repeaters can interconnect different media types but cannot convert protocols.


The main purpose of a repeater is to extend the maximum distance of a single network segment. Let’s say you have a workstation that is 150 meters (about 450 feet) from a hub. If your network is 10BaseT Ethernet, you won’t be able to connect the workstation directly to the hub because the distance between the hub and the workstation is longer than the maximum segment length of 10BaseT Ethernet (100 meters). For this reason, you place a repeater about 50 to 100 meters between the two.


If it’s practical, you could also move the hub. But since hubs are usually close to where all wires come together, this is often neither the best nor the most practical solution.


A repeater is the least expensive of all network devices, but since a repeater can do nothing to segment network traffic, it does little to decrease network traffic. A repeater can actually do more harm than good because it propagates everything, including noise and error packets.

The Hub


A hub, which we also discussed in Chapter 2, is the central device in a star topology. Hubs are most commonly used in 10BaseT or 100BaseT Ethernet

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