Allied Telesis AT-8550SP - Manual (Page 18)

Overview
18
10/100Base-TX Twisted Pair Ports
This section applies to the AT-8524M, AT-8524POE, AT-8550GB, and
AT-8550SP switches.
Type of
Connector
The 10/100Base-TX twisted pair ports feature 8-pin RJ-45 connectors.
Only four of the pins are used when a port is operating at 10 or 100 Mbps
Speed The twisted pair ports are 10/100Base-TX compliant and are capable of
10 megabits per second (Mbps) or 100 Mbps speeds. You can set the
port speed manually or, because the ports are IEEE 802.3u Auto-
Negotiation compliant, you can let the switch set each port’s speed
automatically. With Auto-Negotiation, the switch automatically matches
the highest possible common speed between each switch port and each
end node. For example, if an end node is capable of only 10 Mbps, the
switch sets the port connected to the end node to 10 Mbps.
Note
Auto-Negotiation is activated as the default on all twisted pair ports
on the switch. To deactivate Auto-Negotiation and set the speeds
manually, refer to the AT-S62 Management Software User’s
Guide.
Duplex Mode Each twisted pair port on the switch can operate in either half- or full-
duplex mode. The twisted pair ports are IEEE 802.3u-compliant and will
Auto-Negotiate the duplex mode setting.
If desired, you can disable Auto-Negotiation on one or all of the switch
ports so that you can set the duplex mode manually through the
switch’s management software.
Note
In order for a switch port to successfully Auto-Negotiate its duplex
mode with an end node, the end node should also be using Auto-
Negotiation. Otherwise, a duplex mode mismatch can occur. A
switch port using Auto-Negotiation will default to half-duplex if it
detects that the end node is not using Auto-Negotiation. This will
result in a mismatch if the end node is operating at a fixed duplex
mode of full-duplex.
To avoid this problem, when you connect an end node with a fixed
duplex mode of full-duplex to a switch port, you should use the
AT-S62 management software to disable Auto-Negotiation on the
port and set the port speed and duplex mode manually.