Chapter 1: Overview
24
10/100/
1000Base-T
Twisted Pair
Ports
This section applies to Port 49R and Port 50R on the AT-8550GB and
AT-8550SP switches.
Type of Connector
The ports have 8-pin RJ-45 connectors. The ports use four pins when
operating at 10 or 100 Mbps and all eight pins when operating at
1000 Mbps.
Speed
The ports can operate at 10, 100, or 1000 Mbps. The speed is set
automatically through Auto-Negotiation or you can set the speed to 10 or
100 Mbps manually through the management software.
Note
Ports 49R and 50R can operate at 1000 Mbps only when set to
Auto-Negotiation. You cannot manually set these ports to 1000
Mbps.
Duplex Mode
The ports can operate in either half- or full-duplex mode. The ports are
IEEE 802.3u compliant and will Auto-Negotiate the duplex mode. If
needed, Auto-Negotiation can be disabled so that you can set the duplex
mode manually through the management software.
Note
In order for a 10/100/1000Base-T 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 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 10/100/1000Base-T 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.
Maximum Distance
The ports have a maximum operating distance of 100 meters (328 feet).
Type of Cable