Allied Telesis AT-8100S/24 User Manual

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Chapter 1: Overview
30
10/100Base-TX Twisted Pair Ports
The switches have 8 or 24 10/100Base-TX ports.
Speed
The ports can operate at either 10 or 100 Mbps. The speeds may be set 
manually using the management software or automatically with Auto-
Negotiation (IEEE 802.3u), the default setting.
Duplex Mode
The twisted pair ports can operate in either half- or full-duplex mode. The 
duplex mode determines the manner in which a port transmits data. A port 
set to half-duplex can either transmit or receive data at one time, while a 
port operating in full-duplex can transmit and receive data at the same 
time. The best network performance is achieved with the full-duplex 
setting, but not all network equipment is designed to support that duplex 
mode.
The duplex modes, like port speeds, may be set manually using the 
management software or automatically with Auto-Negotiation (IEEE 
802.3u), the default setting.
The speed and duplex mode settings of a port may be set independently 
of each other. For example, a port may be configured such that its speed 
is set manually while its duplex mode is established through Auto-
Negotiation.
Note
A switch port that is connected to a network device that does not 
support Auto-Negotiation and has a fixed duplex mode of full-duplex 
should not set its duplex mode with Auto-Negotiation. A duplex-
mode mismatch in which a switch port and a network device operate 
at different duplex modes, may occur. The duplex modes of switch 
ports that are connected to network devices that do not support 
Auto-Negotiation should be set manually through the management 
software.
Wiring
Configuration
The wiring configuration of a port can be MDI or MDI-X. The wiring 
configurations of a switch port and a network device connected with 
straight-through twisted pair cabling have to be opposite, such that one 
device is using MDI and the other MDI-X. For instance, a switch port has 
to be set to MDI-X if it is connected to a network device set to MDI.
You may set the wiring configurations of the ports manually or let the 
switch configure them automatically with auto-MDI/MDI-X (IEEE 802.3ab-
compliant). This feature enables the switch to negotiate with network 
devices to establish the proper settings, so that the ports on the devices 
are using different wiring configurations.