Fddi Standards; Multimode Fiber Standards - 3Com CoreBuilder 2500 Getting Started Manual

FDDI S
D
This appendix describes multimode and single
mode FDDI fiber standards. When planning your
installation, thoroughly inspect your present cabling
to determine if it meets the specifications in the
cabling system plan and standards used at your site.
In addition to adhering to your local standards, all
cable must conform to the American National
Standard FDDI Physical Layer Medium Dependent
(PMD) standard, ISO.166-1990, American National
Standards Institute, which defines the Physical
Medium Dependent (PMD) layer of the FDDI
network. Currently, there are two approved PMD
standards:
Multimode Fiber (MMF-PMD), which is defined
in ANSI standard X.3-166-1992
Single Mode Fiber (SMF-PMD), which is defined
in ANSI standard X.3-184-198x
For the CoreBuilder ™
multimode fiber (MMF-PMD) 62.5/125 mm and
Category one (1) single mode fiber (SMF-PMD).
When deciding whether to use multimode or single
mode fiber, determine the maximum interstation
distance (the distance from the CoreBuilder system
to any potential workstation):
TANDARDS
2500 system, 3Com supports
If the maximum interstation distance is less than
or equal to 2 kilometers (1.25 miles), use
multimode fiber (MMF-PMD).
If the maximum interstation distance is greater
than 2 kilometers (1.25 miles) and less than or
equal to 14.4 kilometers (8.6 miles), use single
mode fiber (SMF-PMD).
Standards for multimode and single mode fiber are
described in the rest of this appendix.

Multimode Fiber Standards

The MMF-PMD standards define the requirements
for an FDDI cable plant to support an interstation
distance of up to 2 kilometers (1.25 miles) of
multi-mode fiber. The cable plant includes all fiber
optic components between any two
communicating FDDI stations and their associated
"station-to-network" connectors at each end.
To determine whether your cable plant complies
with the MMF-PMD standard, take these steps:
Compare the specifications of the fiber you are
using to standard specifications, as described in
the next section.