10BASE5

10BASE5

The 10BASE5 cabling topology (Thicknet) uses an external transceiver to attach to the network adapter card (see Figure 4.10). The external transceiver clamps to the Thicknet cable (as described in Chapter 3). An Attachment Universal Interface (AUI) cable runs from the transceiver to a DIX connector on the back of the network adapter card. As with Thinnet, each network segment must be terminated at both ends, with one end using a grounded terminator. The components of a Thicknet network are shown in Figure 4.11.

The primary advantage of 10BASE5 is its capability to exceed the cable restrictions that apply to 10BASE2. 10BASE5 does pose restrictions of its own, however, which you should consider when installing or troubleshooting a 10BASE5 network. As with 10BASE2 networks, the first consideration when troubleshooting a 10BASE5 network should be the established cabling rules and guidelines. You must follow several additional guidelines, along with the 5-4-3 rule, when configuring Thicknet networks, such as the following:

The minimum cable distance between transceivers is 2.5 meters (8 feet).
You may not go beyond the maximum network segment length of 500 meters (1,640 feet).
The entire network cabling scheme cannot exceed 2,500 meters (8,200 feet).
One end of the terminated network segment must be grounded.
Drop cables (transceiver cables) can be as short as required but cannot be longer than 50 meters from transceiver to computer.
The maximum number of nodes per network segment is 100. (This includes all repeaters.)

The length of the drop cables (from the transceiver to the computer) is not included in measurements of the network segment length and total network length. Figure 4.12 shows two segments using Thicknet and the appropriate hardware.

As Chapter 3 mentions, Thicknet and Thinnet networks are often combined, with a Thicknet backbone merging smaller Thinnet segments. (See Chapter 3 for more on 10BASE5’s Thicknet cabling.)