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3-1
Chapter Three Installation
In planning or expanding a Token Ring LAN, the best place to start
is a map showing workstation locations and wiring closets. All cable
distances should appear on this map. Distance related to each MAU
lobe connection and each MAU Ring In and Ring Out connection are
factors of concern. A repeater can link MAUs separated by distances
beyond the limits of a direct connection.
You should locate any repeaters in the same wiring closet as your
MAUs. In instances where you have a non-powered MAU, the total
distance from the repeater to the MAU plus the cable distance from
the highest numbered MAU lobe to a workstation should not exceed
360 feet (110 meters) when operating at 16 megabits per second.
Table 3-1 shows the maximums for workstations and cable distances.
NOTE:
The current accepted building standard (EIA/TIA 568 A/B)
defines the maximum workstation-to-wiring closet cable
length to be no more than 330 feet (100 meters) for Category
5 cable.
Table 3-1. Cable Characteristics.
Network Cabling Medium Transmission Distance (max.)*
UTP Cable Workstations 16 Mbps 4 Mbps
Type 3 72 (max.) 180 ft (55 m) 450 ft (137 m)
Category 4† 225 (max.) 300 ft (91 m) 750 ft (229 m)
Category 5† 260 (max.) 330 ft (100.6 m) 825 ft (251 m)
STP Cable
Types 1 & 2
260 (max.) 400 ft (122 m) 1000 ft (305 m)
*
Maximum lobe length equals maximum transmission distance with all MAUs in same closet.
† UTP categories have improved distances due to more frequent and uniform twists per foot.
Category 5 can support 100 Mbps.
Those wishing to fabricate their own cables can find pin-out
information in Appendix A.