Cabletron Systems 100BASE-FX, Cabling Manual

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Fast Ethernet Network Requirements
7-4 100BASE-FX (Multimode)
100BASE-FX (Multimode)
All Cabletron Systems 100BASE-FX products require that installed facility cabling
and cable hardware meet the following minimum specifications. If a network
cabling installation is not within the limitations presented here, the operation of
the 100BASE-FX products may be affected.
Cable Type
Networking devices built to the 100BASE-FX specification require specific types
of cabling. 100BASE-FX multimode fiber optic devices manufactured by
Cabletron Systems are able to support connections to and from 62.5/125
µ
m
multimode fiber optics.
Attenuation
Multimode fiber optic cables must be tested for attenuation with a fiber optic
attenuation test set. The test set must be configured to determine attenuation of
the cable at a wavelength of 850 nm. The attenuation test will confirm or deny that
the cable falls within an acceptable level. The acceptable level of attenuation for a
100BASE-FX cable is 11.0 dB.
Insertion Loss
The 100BASE-FX specification allows for a total dB loss of 10.0 dB or less between
any two stations or devices connected by fiber optic cabling. When calculating
insertion loss, you must consider and count any loss introduced by fiber optic
splices, barrel connectors, distribution boxes or other cable management devices.
The typical dB loss for a splice or a connector is less than 1 dB. The loss statistics
for any fiber optic cable management hardware should be available from the
manufacturer.