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Dual Speed Functionality & Switching
The TN-5308’s 10/100 Mbps switched M12 ports auto negotiate with the
connected device to use the fastest data transmission rate supported by
both devices. All of Moxa’s ToughNet switches are plug-and-play devices,
so that software configuration is not required. The half/full duplex mode
for the switched M12 ports is user dependent and changes (by
auto-negotiation) to full or half duplex, depending on which transmission
speed is supported by the attached device.
Switching and Address Learning
The TN-5308 has a MAC address table that can hold up to 1000 node
addresses, which makes it suitable for use with large networks. The
address tables are self-learning, so that as nodes are added or removed,
or moved from one segment to another, the TN-5308 automatically keeps
up with new node locations. An address-aging algorithm causes the
least-used addresses to be deleted in favor of newer, more frequently
used addresses. To reset the address buffer, power down the unit and
then power it back up.
Switching, Filtering, and Forwarding
Each time a packet arrives at one of the switched ports, a decision is made
to filter or forward the packet. Packets with source and destination
addresses belonging to the same port segment will be filtered,
constraining those packets to one port, and relieving the rest of the
network from the need to process them.
A packet with destination address on another port segment will be
forwarded to the appropriate port, and will not be sent to the other ports
where it is not needed. Packets that are used in maintaining the operation
of the network (such as the occasional multi-cast packet) are forwarded
to all ports.
The TN-5308 operates in the store-and-forward switching mode, which
eliminates bad packets and enables peak performance to be achieved
when there is heavy traffic on the network.
LED Indicators
Several LED indicators are located on the TN-5308’s front panel. The
function of each LED is described in the table below.
LED
Color
State
Description
PWR
AMBER
On
Power is being supplied to the power
input.
Off
Power is not being supplied to the
power input.
TP
(10M)
AMBER
On
TP port’s 10 Mbps link is active.
Blinking Data is being transmitted at 10 Mbps
Off
TP port’s 10 Mbps link is inactive.
TP
(100M)
GREEN
On
TP port’s 100 Mbps link is active
Blinking Data is being transmitted at 100 Mbps.
Off
TP port’s 100 Mbps link is inactive.
