What Is a Network Gateway?

A network gateway joins two networks so the devices on one network can communicate with the devices on another network. A gateway can be implemented completely in software, hardware, or in a combination of both. Because a network gateway, by definition, appears at the edge of a network, related capabilities like firewalls and proxy servers tend to be integrated with it.

Types of Gateways for Homes and Small Businesses

Whichever type of network gateway you use in your home or small business, the function is the same.

It connects your local area network (LAN) and all the devices on it to the internet and from there to wherever the devices want to go. Types of network gateways in use include:

• On home networks and in small businesses, a broadband router typically serves as the network gateway. It connects the devices in your home or small business with the internet. A gateway is the most important feature of a router.
• In some cases, such as in a residence that uses dial-up internet access, the gateway is a router at the internet service provider's location. This has become increasingly less common as dial-up access declines in popularity.
• Some small businesses configure a computer to serve as the gateway to the internet, rather than use a router. This method requires two network adapters—one connected to the local network and one connected to the internet.

Gateways as Protocol Converters

Gateways are protocol converters.

Often the two networks that a gateway joins use different base protocols. The gateway facilitates compatibility between the two protocols. Depending on the types of protocols they support, network gateways can operate at any level of the OSI model.