Making Connections
26
Fiber Optic Module (DFE-260FX)
A fiber optic module provides a standard Fast Ethernet 100BASE-FX fiber
optic connector. A fiber optic connection is particularly useful for creating
a link between two DFE-916 series hub stacks, placing them in separate
collision domains. A link of this sort eliminates the need for a separate
switch to separate stacks into separate domains. Separating the stacks into
separate collision domains overcomes the Fast Ethernet two-repeater limi-
tation, and effectively doubles overall bandwidth.
The fiber optic module includes the following LED indicators:
•
Power/Tx—This LED is lit when the hub is on and blinks when pack-
ets are being transmitted by the module.
•
Link/Rx—This LED is lit when the fiber optic ports are properly con-
nected to a powered-on device and blinks when packets are being
received by the module.
•
Collision—This LED blinks when there are packet collisions on the
fiber optic link.
•
FDX—This LED is lit when the fiber optic port is set for full duplex
transmit and receive. When the LED is off, the fiber optic port is in
half duplex mode.
The duplex mode DIP switch allows you to set the fiber optic link to full
duplex mode operation. Only the right-hand switch (number 2) is active.
Use it to set the duplex mode.
