Allied Telesis AT-MCF2012LC/1 - Manual (Page 31)

AT-MCF2012LC and AT-MCF2012LC/1 Media Converter Modules Installation Guide
31
Channel Operating Modes
A media converter channel has three operating modes. The
operating modes are:
ˆ Link Test mode
ˆ MissingLink mode
ˆ Smart MissingLink mode
The operating mode of a channel is set with the Mode
Selection button on the front panel of the module, as
explained in “Mode Selection Button” on page 36 or with the
optional management module for the chassis.
Link Test
Mode
Contrary to its name, the Link Test operating mode does not
test anything. Rather, what it does is it reflects the current
status of the link between a channel port and its networking
device on the port’s Link LED. The Link LED of a port in the
channel will be on when the port has a link to its networking
device and off when the port does not have a link. (Refer to
Table 3 on page 25.)
This mode does not interfere with the flow of traffic between
the two ports of a channel and so can be used during
normal network operations of a channel. This mode is
typically used when the networking devices connected to a
channel cannot take advantage of the features of the
MissingLink mode, or when you want to use the Link LEDs
of the ports of a channel to troubleshoot a network problem.
This operating mode is also useful after the installation of a
media converter module to verify whether the ports of a
channel have successfully established a link with a
networking device. This is explained in “Verifying the
Installation” on page 53.
MissingLink
Mode
The MissingLink mode enables the twisted pair port and the
fiber optic port of a channel on the media converter module
to pass the “Link” status of their connections to each other.
This ensures that both ports of a channel and,
consequently, the networking devices connected to the
ports, are always aware of a change to the status of the link
of the companion port in a channel.
When a channel in the MissingLink mode detects the loss of
a link on one of its ports, it replicates the loss on the
companion port in the same channel by disabling the