First two sites have good answers at my question:
http://wwwhost.ots.utexas.edu/ethernet/ethernet-home.html
http://www.smc.com/fe/fetech.html
In fact in depends on type of fiber ( monomode or multimode), on type of
hubs ...
Summary of Connectivity Rules
Fast Ethernet
Maximum Network Diameter
Repeater Type Twisted Pair Fiber
Twisted Pair/Fiber
and Number 100BASE-TX/-T4 100BASE-FX
100BASE-T4/-FX 100BASE-TX/-FX
One Class I Repeater 200 m (656 ft.) 272 m (892.2 ft.) 231 m
(757.7 ft.) 260.8 m (855.4 ft.)
One Class II Repeater 200 m (656 ft.) 320 m (1,049.6 ft.) 304 m
(997.1 ft.) 308.8 m (1,012.9 ft.)
Two Class II Repeaters 205 m (672.4 ft.) 228 m (747.8 ft.) 236.3 m
(775.1 ft.) 216.2 m (709.1 ft.)
Maximum Cable Distances
Cable Type Connecting Link Segment
Twisted Pair Any two devices 100 m (328 ft.)
Fiber Switch to Switch, Server or PC
Half Duplex 412 m (1,351.4 ft.)
Full Duplex 2 km (1.24 mi.)
MII Any two devices 0.5 m (1.6 ft.)
SMC Rule
Max. Between Any Two Stations: Two Class II Repeaters One Class I or
Class II Repeater
Number of Link Segments 3 2
Number of Repeaters 2 1
Ethernet
Maximum Distances
Maximum Attachments
Cable Type Cable/Link Segment Diameter Per
Coax Segment/Network
Twisted Pair (10BASE-T) 100 m (328 ft.) 500 m (1,640 ft.) Thick
Coax Segment 100
Fiber (FOIRL) 1.0 km (0.62 mi.) 5 km (3.1 mi.) Thin
Coax Segment 30
Fiber (10BASE-FL) 2.0 km (1.24 mi.) 10 km (6.2 mi.)
Network 1,024
Thin Coax (10BASE2) 185 m (607 ft.) 925 m (3,035 ft.)
Thick Coax (10BASE5) 500 m (1,640 ft.) 2,500 m (8,200 ft.)
AUI 50 m (165 ft.) N/A
SMC Rule
Max. Between Any Two Stations: Thick/Thin Coax Twisted Pair/Fiber
Number of Cable/Link Segments 5 5
Number of Repeaters 4 4
Number of Populated Cable Segments 3 N/A
Thanks to all
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| Yves LAMBERT |
| Administration SUN |
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