Securing a device on a public IP

A static public IP makes a device reachable from anywhere, which is the point: you can view the camera or manage the router from your desk. It also means automated scanners will find it, usually within hours. A device on a public address needs to be secured before it goes live, not after.

Why it matters on mobile in particular

Every ThingSIM SIM has a private IP address by default, which nothing on the internet can reach. Adding a static public IP (£8 a month per SIM) removes that protection on purpose. From then on, the device's own security is what stands between it and the internet.

The checklist

Work through this for every device before it gets a public address:

1. Change default passwords. Default usernames and passwords for cameras and routers are published and tried constantly. Use a long, unique password for each device.
2. Update the firmware. Install the manufacturer's latest firmware and turn on automatic updates if the device offers them.
3. Close what you do not need. Turn off services you do not use, such as old web interfaces, Telnet or UPnP, and forward only the ports you need.
4. Never expose the admin page. Keep the router's or device's management interface off the public address wherever possible.
5. Restrict who can connect. If the device or router can limit access to particular source addresses, such as your office, use it.
6. Prefer encrypted access. Use HTTPS or the manufacturer's secure app rather than unencrypted web or video ports.
7. Watch the data. A compromised device often shows up as unexpected data use. Usage alerts in the portal, or the usage webhooks, will flag it; see usage webhooks.

Know when not to use a public IP

A public address is the right tool for one or two devices you connect to yourself. For anything that must not be exposed, such as payment terminals, alarm communicators and fleets that a back office manages, a private network is the better design: a private APN keeps devices unreachable from the internet, and an IPSec VPN lets your systems reach them privately. The comparison guide helps you choose.

If something looks wrong

If a device starts using far more data than usual, or behaves oddly, take it off the public address first, then investigate. You can pause the SIM from the portal straight away to stop it passing data while you check the device, and remove the static IP if it is no longer needed.

Common questions

Is a device on a static public IP safe?

It is as safe as its own security. Change default passwords, update firmware, close unused services and restrict access before it goes live.

What is the safest way to reach devices remotely?

Keep them off the internet with a private APN, IPSec VPN or cloud interconnect, so your systems reach them privately and nothing is exposed.

How do I spot a compromised device?

Unexpected data use is a common sign. Set usage alerts in the portal or subscribe to the usage webhooks so a sudden rise is flagged.