Data Acquisition

Figure 9.2AUI cable connectorsThere are certain requirements if this cable architecture is used in a network. Theseinclude:• Segments must be less than 500 meters in length to avoid signal attenuationproblems• No more than 100 taps on each segment i.e. not every connection point cansupport a tap• Taps must be placed at integer multiples of 2.5 meters• The cable must be terminated with a 50 ohm terminator at each end• It must not be bent at a radius exceeding 25.4 cm or 10 inches• One end of the cable must be earthedThe physical layout of a 10Base5 Ethernet segment is shown in Figure 9.3.Figure 9.310Base5 Ethernet segmentThe Thicknet cable was extensively used as a backbone cable until recently (1995) but10BaseT and fiber are becoming more popular. Note that when a MAU (tap) and AUIcable is used, the on board transceiver on the NIC is not used. Rather, there is a