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ETWORK
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LANNING
2-810 Mbps Ethernet Collision Domain

Maximum Ethernet Cable Distance

Maximum Network Diameter Using Repeaters

SMC 5-4-3 Rule

Cable Type Maximum Length
Twisted Pair, Categories 3, 4, 5 100 m (328 ft)
Thin Coax 185 m (607 ft)
External Transceiver Drop 50 m (165 ft)
Repeater Type
and Number
Twisted Pair
100BASE-TX
1 Class I 200 m (656 ft)
1 Class II 200 m (656 ft)
2 Class II 205 m (672.4 ft)
Between any two PCs or other stations in the same 10 Mbps collision domain,
there may be:
• up to 5 link segments in series
• up to 4 repeaters (hubs)
• up to 3 populated cable segments, that is, segments attached to two or
more PCs (coax networks only)*
* The remaining two segments are unpopulated; these are known as inter-
repeater links or IRLs. This distinction between populated and unpopulated
segments is significant for coax networks only.