Home Networks
Routers, gateways, ports and the small pile of jargon between you and a working connection.
What this covers
Most people arrive at this subject sideways: a game says your NAT type is strict, a camera app wants a port opened, or a support article says to log into your router and nobody said how. This pillar is the whole picture in one read, with each section also written up on its own page.
1. How a home network fits together
There are four pieces, and the router is the only complicated one because it wears two hats at once.
The modem converts your provider's signal, whether that arrives over cable, fiber or phone line, into ordinary networking. The router shares one connection among many devices and performs network address translation between the private and public sides. In most homes these are one rented box, which is why the distinction stays invisible until something breaks.
2. Finding your router's address
Full article →The router's private address is called the default gateway, because it is where your device sends anything not on the local network. It is also the address you type into a browser to reach the router's settings. Same number, two names, which is a large share of why this is confusing.
| Platform | Where to look |
|---|---|
| Windows | Command Prompt, run ipconfig, read "Default Gateway" |
| macOS | System Settings, Network, Details, TCP/IP, read "Router" |
| iPhone or iPad | Settings, Wi-Fi, the blue circle beside your network, read "Router" |
| Android | Settings, Network, your Wi-Fi network, Advanced, read "Gateway" |
| Linux | ip route | grep default |
3. What 192.168.1.1 actually is
Full article →It is a private address, and it is not special. It is simply the address most manufacturers picked as the default for the router itself, out of the 65,536 available in the 192.168.0.0/16 range.
Because it is private, it means something different on every network on earth. Typing it into a browser reaches your router, and typing it at a friend's house reaches theirs. There is no shared 192.168.1.1 out on the internet, and no way for anyone outside to use it to reach you.
Your router probably uses a different default. 192.168.0.1, 10.0.0.1, 192.168.1.254 and 10.0.0.138 are all common. Rather than guessing, read the actual gateway address using the table above. That always gives the right answer.
4. Ports and port forwarding
Full article →If an address is a building, a port is an apartment number. One address, up to 65,535 numbered doors, each one potentially a different service.
Outgoing connections work without any configuration, because your router records each one and knows where the reply belongs. Incoming connections are the problem: nothing inside asked for them, so there is no entry in the table and the router drops them.
That is genuinely useful and genuinely a hole. The address space is scanned continuously by automated systems, so an exposed service is found within hours regardless of whether anyone was looking for you specifically. Forward only what you need, keep it updated, and delete the rule when you stop using it.
5. NAT types, and why games care
Full article →Console games report a NAT type because peer-to-peer connections between players are difficult through translation. Both players are behind routers that drop unsolicited traffic, so something has to arrange the introduction.
| Type | What it means | Effect |
|---|---|---|
| Open, or Type 1 | No translation in the way, or everything forwarded | Connects to anyone. Rare and not really desirable at home |
| Moderate, or Type 2 | Ordinary NAT, with the console able to negotiate | Fine. This is the normal, healthy state |
| Strict, or Type 3 | Negotiation is failing | Party chat and matchmaking problems |
Strict usually has one of three causes: UPnP is turned off, so the console cannot ask for the ports it needs; there are two routers in series, each translating, which is double NAT; or your provider uses carrier-grade NAT, in which case the second translation is on their equipment and nothing you change at home will fix it.
Compare your router's WAN address with the one on our front page. If the router shows something between 100.64 and 100.127, they will never match and no amount of port forwarding will work. That is a phone call to your provider, not a settings change.
6. The problems that keep coming up
Double NAT
Two routers in a row, each performing translation. Usually a provider's combined modem and router feeding a router you bought. The fix is to put the provider's box into bridge or passthrough mode so only one device is translating.
An address that keeps changing on a device
Your router hands out addresses from a pool with a lease, so a device can come back on a different one. If something needs to be reachable at a fixed address inside your house, use a DHCP reservation in the router, which pins one address to one device. That is better than setting a static address on the device itself, which the router does not know about and may hand out to something else.
169.254 addresses
A device assigns itself one of these when it asks for an address and nothing answers. It is a symptom rather than a setting: a cable that is not seated, a Wi-Fi association that did not complete, or DHCP switched off on the router.
Reaching your home from outside
Your public address is likely dynamic, so anything relying on it will break when it changes. Dynamic DNS gives you a hostname that follows the address automatically, though a mesh VPN is often less work and much less exposure.