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What Counts as a Smart Device

The gadgets that quietly join your Wi-Fi, and why attackers like them.

Gadgets that join your Wi-Fi

A smart device is an everyday object that connects to the internet. People also call these gadgets IoT devices. IoT stands for the Internet of Things, which simply means things, not computers, that go online.

You may have more of them than you think. Walk through a typical home:

• Smart TV: streams shows and often has its own apps.
• Smart speaker: plays music and answers questions when you talk to it.
• Smart plug: plugs into the wall so you can switch a lamp on from your phone.
• Security camera: sends video to your phone.
• Video doorbell: a doorbell with a camera. It alerts your phone when someone rings or walks up.
• Smart thermostat: controls the heating and cooling, even when you're away.

Other common ones are light bulbs, baby monitors, robot vacuums, printers and even fridges.

Here is a simple test. If a gadget asks for your Wi-Fi password during setup, it is a smart device. If you control it from an app on your phone, it is a smart device.

Each one is a small computer. It has a chip, a little memory and its own software. It just doesn't have a screen and keyboard like a laptop. That matters, because every computer on your network needs care, even the tiny ones.

Most homes never count these gadgets. A quick count is a good first step. Your router's app or admin page lists everything connected. Check the number there.

Why gadgets get picked on

Attackers like smart devices for two simple reasons.

Weak passwords. Many gadgets used to ship with a default password. That is a password set at the factory, like "admin" or "1234". It is often the same on every unit. Lists of these passwords are easy to find online. If nobody changes it, anyone who finds the device can sign in.

Few updates. An update is new software from the maker that fixes problems, including security holes. Phones and laptops get updates often. Many cheap gadgets get very few, and some get none at all after a year or two. A hole that is never fixed stays open.

So what does an attacker want with your doorbell? Usually not your video. They want its power and its internet connection.

They take over thousands of gadgets and control them all together. A group of hijacked devices working for an attacker is called a botnet. The owners usually notice nothing.

The best-known example is Mirai. In 2016, it took over many cameras, video recorders and home routers. It got in mostly by trying a short list of default usernames and passwords.

The attackers then told all those devices to flood one company with traffic at the same moment. That company helped direct visitors to many big websites. For hours, lots of people in the US couldn't reach popular sites.

The lesson is hopeful. Changing default passwords and keeping gadgets updated stops this kind of attack. The rest of this course shows you how.