How to Configure Duplex on a Router

Enabling duplex on a router can improve the efficiency of your network.

Enabling full duplex at a high speed can improve the efficiency of data transfer on your network for an office or business. Duplex mode allows for two-way communication, meaning that data can be sent and received at the same time. Not all routers have this capability. For the ones that do, the exact way to enable it varies, so consider a few general steps.

Instructions

1. Check to see if your router is already in duplex mode. Some routers, such as the Linksys WRT54G, are equipped with a light that says "full/coll." When solidly lit, this light indicates that the connection with the Ethernet port to which it corresponds is in full duplex mode. This light may periodically blink, but it doesn't indicate a loss of communication.

2. Make sure your network adapter is in full duplex mode. To do this, select the Start menu, "Control Panels" and then "Network and Internet" or "Network Connections." You should see an icon for your Local Area Connection in this list. Right-click on it and select "properties." Under the "General" tab of the popup window that follows, select "configure" and then the "advanced" tab. In the "Properties" list, select "Speed and Duplex." In the value column to the right, select "100 Mb full." Be sure to check this on every computer in your network.

3. Contact your router manufacturer. If all of your network adapters are set to full duplex and the indicator light is still off or constantly blinking, full duplex may not be enabled on your router. Not all routers have this capability. For the ones that do, the process on how to enable it varies considerably between manufacturers. If you are unable to locate your manual, contact the customer support department of your router manufacturer.

4. Reboot your modem. Another possible reason that your duplex indicator light is blinking could be a connectivity issue, such as packet loss. Sometimes these issues can be corrected by simply unplugging the power on your modem and plugging it back in after 20 seconds. If this hasn't corrected the issue, contact your Internet service provider to see if there have been any routing issues reported in your area.

Tips & Warnings

• Some routers may require the purchase of an additional switch to set a network in full duplex mode.

References

• My-Network.Info: How to Change Your Network Card to Half or Full Duplex
• Cisco: Home Support: Linksys WRT54G Users Manual