Gateway - Your Door to the Internet
How your router bridges your home network and the wider internet
What Is a Gateway?
A gateway (or default gateway) is the device that connects your local home network to the internet. In almost every home, this is your router.
Think of your home network as a house and the gateway as the front door. All outgoing mail (internet requests) goes through the front door, and all incoming mail (website responses) comes back through it.
Your gateway's address is usually something like 192.168.1.1 or 192.168.0.1 - that's your router's private IPThe IP address your router uses on the local (home) side of the network. More Info… on the home network side.
How Does Your Computer Know the Gateway?
When your computer connected to the network, DHCPThe automatic address-assignment service on your router. More Info… told it: "The gateway is 192.168.1.1." Your computer saved this and now knows: anything that isn't on my local network should be sent to 192.168.1.1.
How Routing Works (Simply)
When your computer wants to send data somewhere, it makes a simple decision:
- Is the destination on my local network? (The subnet maskTells your computer which IP addresses are neighbours on the same local network. helps determine this)
- If yes → send directly to that device using its MAC addressThe hardware ID used for direct device-to-device communication on the local network. More Info…
- If no → send to the gateway (router), and let it figure out the rest
So when you visit google.com, your computer knows Google isn't on your home network, so it sends the request to the gateway.
NAT - How One Public IP Serves All Your Devices
Your router performs NAT (Network Address Translation). Here's what happens:
Your Phone (192.168.1.16) → Router → Internet
Websites see: Your Router's Public IP (e.g., 203.45.67.89)
The router keeps a table internally: "Request #1 came from the laptop, Request #2 came from the phone." When responses come back, it knows exactly which device to forward each one to.
This is why when you check your IP address from any device at home, they all show the same public IP.
Your Router Has Two IP Addresses
Your router sits between two networks, so it has an address on each side:
- LAN side (internal): 192.168.1.1 - this is what your devices see as the gateway
- WANWide Area Network - the outside connection going to your ISP. More Info… side (external): Your public IP (assigned by your ISP) - this is what the internet sees