Switching And Address Learning; Auto-Negotiation And Speed Sensing - Moxa Technologies EtherDevice User Manual

Switching and Address Learning

MOXA EtherDevice Server has an address table that can hold up to 4K 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, MOXA
EtherDevice Server 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.

Auto-Negotiation and Speed Sensing

All of MOXA EtherDevice Server's RJ45 Ethernet ports independently support
auto-negotiation for speeds in the 10BaseT and 100BaseTX modes, with operation
according to the IEEE 802.3u standard. This means that some nodes could be operating at
10 Mbps, while at the same time, other nodes are operating at 100 Mbps.
Auto-negotiation takes place when an RJ45 cable connection is made, and then each time a
LINK is enabled. MOXA EtherDevice Server advertises its capability for using either
10 Mbps or 100 Mbps transmission speeds, with the device at the other end of the cable
expected to similarly advertise. Depending on what type of device is connected, this will
result in agreement to operate at a speed of either 10 Mbps or 100 Mbps.
If a MOXA EtherDevice Server RJ45 Ethernet port is connected to a non-negotiating
device, it will default to 10 Mbps speed and half-duplex mode, as required by the IEEE
802.3u standard.
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