Switching And Address Learning; Auto-Negotiation And Speed Sensing - Weidmuller IE-SW-VL09T-6TX-3SC Hardware Installation Manual

Switching and Address Learning

IE-SW-VL09-Switches have an address table that can hold up to 1K node
addresses, which makes i t suitable for use with large networks. The address
tables are self-learning, s o that as nodes are added or removed, or moved from
one segment to another, the Ethernet switches 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 the RJ45 Ethernet ports independently support auto-negotiation f or
speeds in the 10BaseT and 100BaseTX modes, with operation according to the
IEEE 802.3u standard. This means that some nodes could be oper ating 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. An IE-SW-VL09-Switch 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 agreemen t to operate at a spe ed
of either 10 Mbps or 100 Mbps.
If an RJ45 Ethernet port is connected to a non-negotiating device, the default
values 10 Mbps speed and half-duplex mode will be setup, as required by the
IEEE 802.3u standard.
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