Enterprise Design Guide - Public - CommScope

Fiber Optic Cable Distances for 100 Mb/s Networks
TIA/EIA 568 distance standards were initially written for a ‘FDDI (Fiber Distributed Data
Interface) grade’ 62.5 µm multimode 160/500 MHz•km bandwidth fiber powered by 850
µm Light Emitting Diodes (LEDs). These standards were written to support 100 Mb/s backbones
with 10 Mb/s horizontal links. Using a fiber with higher bandwidth, or even using single-mode
fibers, will produce longer transmission distances than defined by the standard.
Outlet
90 m
Outlet
300 meters in
collapsed
backbones
Equipment room
(intermediate
crossconnect)
In a 100 Mb/s network, the 90 meters of horizontal cabling can be either twisted pair or
multimode fiber. Collapsed backbone connections should be multimode fiber and limited to
300 meters. Campus links between active equipment should be limited to 2000 meters for
multimode fiber.
Single-mode fiber can be used anywhere in the network, but it is necessary where the
transmission distance exceeds 2000 meters. Remember that single-mode fibers require the use
of more expensive electronics.
Fiber
Description
Bandwidth (MHz•km)
850/1300 nm
100 Mb/s Range
with 850 nm LED
50 µm OM4 4700*/500 300 m 2000 m
50 µm OM3 2000*/500 300 m 2000 m
50 µm OM2+ multimode 950*/500 300 m 2000 m
50 µm OM2 multimode 500/500 300 m 2000 m
62.5 µm multimode 200 /500 300 m 2000 m
100 Mb/s Range
with 1300 nm LED
8.3 µm single-mode NA 2 km and up** 2 km and up**
* Effective Modal Bandwidth (EMB)
**using 1310 & 1550 nm lasers
Telecommunications Room
(horizontal crossconnect)
2000 meters multimode
3000+ meters single-mode
300 meters between
crossconnects
total cabled distance between active
(distributed
equipment shall not exceed 2000
backbones)
meters for multimode fiber
1700 meters multimode
2500+ meters single-mode
Central
equipment
room
(main crossconnect)
to Local
Access
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