Allied Telesis AT-MCF112VF, SM, LH - Manual (Page 17)

AT-MCF106xx and AT-MCF112xx Installation Guide
7
The value to this type of network monitoring and fault notification is that
some hubs and switches can be configured to take a specific action in the event
of the loss of connection on a port. In some cases, the unit can be configured to
seek a redundant path to a disconnected node or send out a trap to a network
management station, and so alert the network administrator of the problem.
In the example above, once the AT-8224XL Ethernet switch realizes that its
connection has been lost to the media converter, and, consequently, to the
AT-FS709FC switch, the switch can send a trap to the management station,
alerting the network administrator of the problem.
Note
The MissingLink feature is disabled when you perform a link test
with the Link Test switch. Consequently, to ensure that the
MissingLink feature is enabled on the media converter, always set the
Link Test switch to the Normal position during normal network
operations.
Duplex Mode
The duplex mode refers to the manner in which a node sends and receives
data on the network. Depending on its capabilities, a node can operate in
either half-duplex mode or full-duplex mode. A node that is operating in half-
duplex mode can either send data or receive data, but not both at the same
time. A node that is operating in full-duplex mode can send and receive data
simultaneously. Naturally, the best network performance is achieved when a
node can operate at full-duplex, since the node is able to both send and receive
data at the same time.
The AT-MCF106xx and AT-MCF112xx Multichannel Media Converters are
transparent to the duplex mode of the nodes that are connected to their ports.
That is, the units can operate with nodes operating in either half-duplex and
full-duplex mode. However, the two nodes that are connected to the same
twisted pair and fiber optic ports of a channel on the media converter must
operate with the same duplex mode.
For example, assume that you connected a node operating at half-duplex to
the twisted pair port of a channel on the media converter and a node operating
at full-duplex to the fiber optic port of the same channel. This would be an
invalid configuration and could adversely affect the performance of the
network. Either the node connected to the twisted pair port would have to be
changed to full-duplex (if it supports that capability), or the node connected to
the fiber optic port would need to be changed to half-duplex.