What Is a Default Gateway in Networking?

A default gateway makes it possible for devices in one network to communicate with devices in another network. If a computer, for example, requests a web page, the request goes through the default gateway before exiting the local network (LAN) to reach the internet.

Think of a default gateway as an intermediate device between the local network and the internet. The default gateway transfers internal data to the internet and back again.

How Traffic Moves Through a Default Gateway

All the clients on a network point to a default gateway that routes their traffic. The default gateway device passes this traffic from the local subnet to devices on other subnets. The default gateway connects a local network to the internet, although internal gateways for communication within a local network are used in corporate networks.

The default gateway in a home network, for example, understands specific routes that must be taken to move internet requests from a computer out of the network and onto the next piece of equipment that can understand what needs to be done. From there, the same process happens until the data reaches its destination.

With each network that the traffic arrives at, that network's default gateway relays the information to the internet and back to the computer, which requested it.

When traffic is bound for other internal devices and not a device external to the local network, the default gateway is used to understand the request, but instead of sending the data out of the network, it points it to the correct local device.

This process is understood based on the IP address that the originating device requests.

Types of Default Gateways

Internet default gateways are typically one of two types:

• In home or small business networks with a broadband router to share the internet connection, the home router serves as the default gateway.
• In home or small business networks without a router, such as for residences with dial-up internet access, a router at the internet service provider location serves as the default gateway.

Default network gateways can also be configured using a computer instead of a router. These gateways use two network adapters: one is connected to the local subnet and the other is connected to the outside network.

Either routers or gateway computers can be used to network local subnets such as those in large businesses.

How to Find Your Default Gateway IP Address

You'll need to know the IP address of the default gateway if there's a network problem or to make changes to the router.

• In Microsoft Windows, the IP address of a computer's default gateway can be accessed through Command Prompt with the "ipconfig" command, as well as through the Control Panel.
• In macOS and Linux, the "netstat" and "ip route" commands are used to find the default gateway address.