What Is a Gateway?
a Gateway — a device (usually a router) that connects one network to another and translates between them — the exit point traffic uses to leave its local network.
How it works
A gateway sits at the boundary between networks. For a typical device, its "default gateway" is the router it sends traffic to whenever the destination is on a different network. More broadly, a gateway can also translate between different protocols or systems, but in everyday networking it means the router bridging your LAN to other networks.
Why it matters
The gateway concept is fundamental — every device needs to know its gateway to reach anything beyond its own subnet. "Can't reach the internet but local devices work" almost always points to a gateway problem. See default gateway for the detailed version.
Frequently asked questions
What is a gateway in networking?
A device (typically a router) connecting one network to another — the exit point traffic uses to reach destinations outside its local network.
What is the difference between a gateway and a router?
A router is a type of device; 'gateway' describes its role of bridging networks. A device's 'default gateway' is the router address it uses to leave its subnet.
Why can't I reach the internet if my gateway is wrong?
Without a correct default gateway, your device can't send traffic beyond its own subnet — local communication works, but nothing external is reachable.
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