100Base-Fx (Multimode); Cable Type; Attenuation; Insertion Loss - Cabletron Systems 100BASE-FX Cabling Manual

Enterasys 100base-fx transceivers: user guide

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Fast Ethernet Network Requirements

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.

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 m

multimode ﬁber optics.

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.

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.

7-4

100BASE-FX (Multimode)

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