Length; Ethernet Foirl (Single Mode); Cable Type; Attenuation - Cabletron Systems 100BASE-FX Cabling Manual

Ethernet Network Requirements

Length

The 10BASE-F specification limits a multimode fiber optic cable segment to 2 km
or less. Assuming that a fiber optic cable meets all other limitations for 10BASE-F
usage, it is possible to extend a multimode fiber optic link to an absolute
maximum of 2 km. At a length of more than 2 km, the propagation delay
introduced by the multimode fiber optic cable segment may exceed the 25.6 s
limit of the Ethernet specification and cause excessive OOW errors. Cabletron
Systems does not recommend the installation or use of any multimode fiber optic
cable segment that exceeds 10BASE-F limitations of 2 km.
Older networking equipment for fiber optic connections may be built to the
FOIRL specification. FOIRL devices will support a multimode fiber optic link of
up to 1 km.

Ethernet FOIRL (Single Mode)

All Cabletron Systems FOIRL products require that installed single mode fiber
optic 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 FOIRL products may be affected.

Cable Type

FOIRL network devices require specific types of cabling. FOIRL single mode fiber
optic devices manufactured by Cabletron Systems are able to support connections
to and from the following types of single mode fiber optics:
•
•
Some Cabletron Systems single mode fiber optic devices may be connected to
multimode fiber optic cabling with measurements of 62.5/125 m, but the greater
optical loss characteristics of multimode fiber optics will limit the maximum
distance of the single mode fiber optic signal to approximately 2 km.

Attenuation

Single mode fiber optic cabling must be tested with a fiber optic attenuation test
set configured to determine attenuation of the cable at a wavelength of 1300 nm.
The acceptable level of attenuation for a single mode fiber optic is less than or
equal to 10.0 dB for any given link.
5-6
8/125 m
12/125 m
Ethernet FOIRL (Single Mode)