How to Use a Comcast Gateway with an Existing Router

Authored by: Support.com Tech Pro Team

1. Introduction

Your Comcast Wireless Gateway has a built-in router, providing a way to connect both your wired, and Wi-Fi devices. Sometimes, you may wish to use your own router instead, and have your Comcast Gateway act simply as a modem.

This is known as as 'Bridging' the Gateway. This guide will walk you through turning on bridge mode for your Comcast Wireless Gateway.

xFi Wireless GatewayxFi Advanced Wireless Gateway

Comcast Wireless Gateway first version.
Comcast Wireless Gateway second version.

2. Notification

Before continuing, it's important to understand what exactly bridge mode does.

By default, your Wireless Gateway offers all the functionality of a modem and router in one device. It turns the signal coming in from the cable line into something a computer can understand, provides a way to connect multiple wired devices, a way for Wi-Fi devices to connect, and offers basic firewall capabilities.

When Bridge mode is enabled, the only function that is still active is turning the signal from the cable line into something a computer can understand; the same function a modem does.

In Bridge mode, your Gateway:

  • Will not provide Wi-Fi, this must be taken care of by your own router
  • Will not provide multiple wired ports, only one will be active
  • Will not provide any routing services, only one device may be connected to your Gateway
  • Will not provide any form of security to your devices
  • In effect, it will act as a standard modem

In most cases, you will need to have your own, separate router available to provide services to your multiple Internet-capable devices.

In most cases, un-setting bridge mode will require factory resetting your Wireless Gateway, and possibly contacting your ISP to re-set this setting.

3. Gateway Connection Check

In order to make changes to the Wireless Gateway, you must be connected to it directly, and not to any other router you may have.

Computer connected to Gateway.

Before continuing, make sure your computer has an Ethernet connection to your Wireless Gateway, or you are connected to the Wi-Fi connection provided by your Wireless Gateway.

4. Bridge Mode

  1. On your computer, open your preferred web browser.
Main Desktop Browsers.
  1. In the address bar at the top, type in 10.0.0.1, and press return or enter.
Address bar with address entered.
  1. Enter your Wireless Gateway Administration Username and Password, then select Logon.If you have not logged in before, or never changed it, the default information is:Username:adminPassword:passwordThis username and password is case sensitive; in this case, it must be all lower-case letters.
Admin tool login with Username, Password, and Logon button highlighted.
  1. On the left, select Gateway > At a Glance.
Gateway administration page with Gateway, At a Glance highlighted.
  1. In the center, for Bridge Mode, select Enable.
Bridge Mode settings highlighted.
  1. A warning message will open, informing you again that the wireless and routing capabilities of your Wireless Gateway are about to be turned off. Select OK.
Warning about bridge mode with OK highlighted.
  1. Your Wireless Gateway will reboot, to complete Bridge Mode setup.

5. Using In Bridge Mode

When your Wireless Gateway is in bridge mode, there are some special considerations you must take into consideration.

Wireless

All wireless functionality is disabled. You will need to use your own router to connect anything wirelessly.

Routing

No routing is performed on traffic coming in. Because of how the Internet works, this means only one device, usually your own router, can be connected to your Wireless Gateway.

Protection

No protection in the form of firewall or even simple network separation is performed. Again, this is fine if the device you intend to connect is your own router, it can provide those services for you.

Only One Wired Connection

Only one Ethernet port on the back of your Wireless Gateway is active, Port One. This is where you will need to plug in your own router.

XB1, XB2, and XB3 Comcast Wireless Gateways

Port one is the only active port for Internet service when Gateway is in bridge mode.

Back of XB1 Gateway with Ethernet Port one highlighted.

XB6 Comcast Wireless Gateways

Port one is the only active port for Internet service when Gateway is in bridge mode.

XB6 Gateway with Ethernet port one highlighted.

6. Unable to Set Bridge Mode

In some cases, some older Wireless Gateways with outdated firmware installed on them can have problems showing the bridge mode setting.

You will need to reach out to Comcast to set bridge mode for you, or replace your Wireless Gateway with a newer model.

7. What's next?