There’s a huge market for 433 MHz alarm system hardware out there ... that pulled them all together into a complete home automation system on the cheap.

He’s using an Arduino Uno and an Ethernet breakout board to hook it up to the network. This allows him to send text messages to himself when the alarm system is armed, disarmed, or triggered.

If your security system works with third-party accessories, you can link your Arduino alarm to that system and let it serve .