Data Cabling Techniques
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2165 ns. Propagation delay of 10BASE5 Ethernet coax is calculated at 4.33 ns/
meter. Both ends of the segment must be terminated with a 50
Ω
termination
with a power rating of 0.5 watts or greater. Earth grounding of the segment
shield must take place at only one point on the cable.
AUI Drop Cables
AUI or Drop cables can be no longer than 50 meters (164 ft.) each.
Attachments may be made only to the cable ends at the 15-pin D-shell
connector. AUI cables may have a maximum 257 ns propagation delay, as
used for computing the worst case propagation delay of a cable system. AUI
cable propagation delay is approximately 5.13 ns/meter. This cable internally
consists of four shielded twisted pair wires with an overall shield and drain
wire; a 15-pin D-shell male connector at one end and a 15-pin D-shell female
connector at the other end. Cable impedance is nominally 78
Ω
. The AUI
cable typically connects a transceiver attached to a coaxial segment to a DTE
(workstation).
