Autonegotiation; Important Considerations - 3Com corebuilder 3500 Implementation Manual

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HAPTER THERNET

Autonegotiation

Important
Considerations
This feature enables some ports to identify and negotiate speed and
duplex mode with a remote device.
You can use this command to configure the same setting on multiple
ports simultaneously. When you specify multiple port numbers, the
system prompts you to choose the setting and then applies it to all of
the ports.
In most cases, if autonegotiation does not properly detect the remote
port speed, the vendor of the remote device implemented either
autonegotiation or a change in port speed in a noncompliant way. If
autonegotiation does not properly detect the port speed, you can
manually set the port speed and duplex mode.
Table 6 lists Ethernet port types on your system, whether they support
autonegotiation, and which features they negotiate.
Table 6 Port Types and Autonegotiation Attributes
Supports
Port Type Autonegotiation?
10/100BASE-TX Yes
100BASE-FX No
1000BASE-SX Yes
1000BASE-LX GBIC Yes
1000BASE-SX GBIC Yes
* LX GBIC, and SX GBIC duplex modes are fixed at full-duplex at this release.
Default Values
Negotiable for Negotiable
Attributes Attributes
Port speed 10 Mbps
Duplex mode Half-duplex
Not applicable Not applicable
Duplex mode Full-duplex
Flow control If autonegotiation
is enabled, the
system's best
effort is On
Duplex mode * Full-duplex*
Flow control If autonegotiation
is enabled, the
system's best
effort is On
Duplex mode* Full-duplex*
Flow control If autonegotiation
is enabled, the
system's best
effort is On