Set Up Speed and Duplex

Overview

NOTE: This section applies to copper connections only. Fiber-based adapters operate at full-duplex only.

In the default mode, a WideBand Professional Series network adapter using RJ-45 connections will attempt to auto-negotiate with its link partner to determine the best setting. If no link is established with the link partner using auto-negotiation, you may need to manually configure the adapter and link partner to the identical setting to establish link and pass packets. See the instructions below for specific steps. 

When auto-negotiation is disabled, the possible settings available are:

10 Mbps, half duplex 10 Mbps, full duplex
100 Mbps, half duplex 100 Mbps, full duplex
NOTE: Per the IEEE specification, gigabit speed and duplex can not be forced. 

The setting you choose must be matched by the link partner. 

Manually Configuring Duplex and Speed Settings

If your switch supports NWay* standard and both the adapter and switch are set to auto-negotiate, full duplex is automatic and no action is required on your part. Not all switches support auto-negotiation. Check with your network system administrator to verify whether your switch supports this feature.

Configuration is specific to the driver you’re loading for your operating system. To set a specific Link Speed and Duplex mode, refer to the section below that corresponds to your operating system.

NOTE: Gigabit speed can not be forced. It can only be auto-negotiated. 
CAUTION: The settings at the switch must always match the adapter settings. Adapter performance may suffer or your adapter may not operate if you configure the adapter differently from your switch. 

Microsoft Windows* (98SE, Me, NT 4.0, 2000, XP)

The default setting is for auto-negotiation to be enabled. Change this only to match your link partner.

NOTE: The adapter will not operate at gigabit speed (1000 Mbps) if you disable auto-negotiation.

If Auto Negotiation is disabled, this lets you specify Forced Speed (to 10 or 100 Mbps, but not 1000 Mbps) and Duplex. In this situation, the Negotiable Speeds and Duplexes checkboxes are disabled, since these are set to advertise speeds during auto-negotiation. 

If Auto Negotiation is enabled, this enables the Negotiable Speeds and Duplexes checkboxes allowing specific speed advertisement and disabling the Forced Speed and Duplex selection buttons. 

If you need to manually change the settings:

  1. Double-click the PROSet II icon from the Control Panel or System Tray.

  2. Click the Link Config tab and highlight the desired adapter in the left window (see example below).

  3. Click the Disabled button and then set the speed and duplex parameters that match your switch.

  4. Click OK to finish.

  5. Restart your computer if prompted.

 

Novell NetWare*

The default setting for auto-negotiation is enabled. Change this only to match your link partner.

NOTE: The adapter will not operate at gigabit speed (1000 Mbps) if you disable auto-negotiation.

Use keyword commands in AUTOEXEC.NCF to force speed and duplex modes as follows:

Speed = 10 | 100 (10 Mbps, 100 Mbps)

This should be followed by one of the following:

Forceduplex = 1 | 2 (half, full)
Autoneg = see table below for settings and values

These keywords are not available in INETCFG. To use these or any of the advanced keywords, either configure the drivers manually, or change them in AUTOEXEC.NCF.

Default operation is auto-negotiation. In this mode, the adapter advertises all supported speed and duplex combinations, and will link at the highest common speed/ duplex combination. 

Speed

If you manually set (force) speed to 10 or 100, then both speed and duplex must be forced, and auto-negotiation is disabled. (Also be sure that the link partner settings match this.) The Autoneg parameter is ignored.

Autoneg

Use the Autoneg parameter when more control is required. When this parameter is used, the Speed and Forceduplex parameters must not be specified. This parameter is a bitmap, based on the following table, that specifies which speed and duplex settings the adapter advertises to a link partner. 

Setting

1000 Full

N/A

100 Full

100 Half

10 Full

10 Half

Value

32

16

8

4

2

1

This parameter is the sum of the values of each setting to advertise. For example, to advertise 1000-Full, 100-Full, and 100-Half modes, the parameter would be set to 32 + 8 + 4 = 44.

CAUTION: When the Speed and Forceduplex keywords are used, auto-negotiation is disabled. To ensure that link is established correctly, auto-negotiation must be disabled on the link partner, and the link should be forced to the same speed and duplex mode used on the adapter.

UnixWare* 7.x and Open UNIX* 8 Servers

The default setting is auto-negotiation enabled. Change this only to match your link partner.

Run the NETCFG configuration program to manually select the speed and duplex settings needed to match your link partner.

Linux*

See e1000.txt.

FreeBSD*

See read_me.txt.

Copyright © 2002, WideBand Corporation. All rights reserved.

WideBand Corporation assumes no responsibility for errors or omissions in this document. Nor does WideBand make any commitment to update the information contained herein.

* Other product and corporate names may be trademarks of other companies and are used only for explanation and to the owners' benefit, without intent to infringe.