What does a default gateway do?

In computer networking, a gateway is a node (a router) on a TCP/IP network that serves as an access point to another network. A default gateway is the node on the computer network that the network software uses when an IP address does not match any other routes in the routing table.


In computer networking, a default gateway is the device that passes traffic from the local subnet to devices on other subnets. The default gateway often connects a local network to the Internet, although internal gateways for local networks also exist.

Internet default gateways are typically one of two types:

On home or small business networks with a broadband router to share the Internet connection, the home router serves as the default gateway.

On home or small business networks without a router, such as for residences with dialup Internet access, a router at the Internet Service Provider location serves as the default gateway.

Default network gateways can also be configured using an ordinary computer instead of a router. These gateways use two network adapters, one connected to the local subnet and one to the outside network. Either routers or gateway computers can be used to network local subnets such as those in larger businesses

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