Network security for homes and small businesses

Why it matters

The number of internet-connected devices in a typical home and workplace keeps rising: phones, laptops, TVs, doorbells, cameras, speakers, thermostats and more. Each one is a potential opportunity for malicious activity, and many receive far less attention than a computer would.

Common router and IoT attacks

Most of these are automated and untargeted — scripts sweeping the internet for anything left with weak defences:

• Botnet recruitment. Malware such as Mirai scans for devices with weak or default passwords, hijacks routers and smart appliances, and conscripts them into networks used to launch large denial-of-service attacks.
• Lateral movement. An attacker compromises a low-security device — a smart bulb or a cheap camera — then uses it as a foothold to reach the computers, phones and network storage that actually matter.
• Credential stuffing and default logins. Automated scripts continually test factory-default and reused usernames and passwords against any device login exposed to the internet.
• Traffic interception. On an unprotected local network, data passing between smart devices and their cloud services can be intercepted to harvest tokens or credentials — a “man-in-the-middle” attack.

Good practice that makes the biggest difference

Most of the benefit comes from a small number of changes:

• Change the router's default admin login. Factory usernames and passwords are public knowledge and the first thing an automated attack tries.
• Use strong WiFi encryption — WPA3, or WPA2 as a minimum.
• Rename the network (SSID). Choose something plain that gives nothing away — not your name, your address, or the router's make and model.
• Run a separate guest network. Visitors and untrusted devices stay isolated and cannot see your computers or private files.
• Put smart-home and IoT devices on their own network, with firewall rules so they cannot reach your phones and computers.
• Keep router and device firmware up to date, and switch off remote-access features you do not use.

Routers I recommend and fit

The routers I generally recommend and install come with up-to-date firewall defences and threat detection built in. With remote management available, it is also much easier for me to keep an eye on any issues and apply updates without another visit.

Where this connects to other work

Security is built into every WiFi and smart home installation I do — see WiFi for Home, WiFi for Business & Holiday Lets and Smart Home Technology. It can also be reviewed as a standalone piece of work on an existing network.