Cabletron Systems 100BASE-FX, Cabling Manual

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FDDI Media
11-14 Connector Types
Figure 11-8. FDDI Media Interface Connector
The MIC connector is designed to prevent the mis-connection of segments and
devices. It is specifically constructed in an asymmetrical fashion that prevents the
connection of transmit strands in the connector to the transmit devices of an FDDI
device.
The sides of the FDDI MIC connector have built-in locking arms that snap the
connector into place once it has been fully inserted and keep it from being pulled
out.
The FDDI standard requires very precise alignment of the fiber optic strands in
order to make an acceptable connection. In order to accomplish this, FDDI
connectors and ports each incorporate “floating” ferrules that make the final
connection between fibers. These floating ferrules are held in place relatively
loosely. This arrangement allows the ferrules to move slightly when making a
connection. This small amount of movement manages to accommodate the subtle
differences in construction found from connector to connector and from port to
port.
The FDDI MIC connector also has a built-in guide channel along one surface. This
guide channel allows small plastic keys to be snapped into place and restrict the
connection of the FDDI MIC connector to certain types of FDDI ports. Keys are
available for FDDI ports of types A, B, or M. Once a MIC connector has been
configured with a B key, it will only fit properly in a B port on an FDDI device.
Locking Arm
Guide Channel
"Floating" Ferrules
1845n27