https://techcrunch.com/2017/09/20/nest-announces-the-499-nest-secure-its-new-alarm-system/

Nest announced a number of new security products today that all aim to keep your home safe from burglars and others you’d rather keep out. In addition to its new Nest Cam IQ Outdoor, the company also launched Nest Secure, its new, fully featured  security system.

The system consists of three hardware products that can also be integrated with the company’s cameras: Nest Guard, the hub of the alarm system with a backup battery and a motion sensor, as well as the Nest Detect, a sensor that checks if a door or window has been opened. Like competing system, the Guard features a siren and cellular backup (for $5 per month) in case your WiFi is down. There’s also a standard keypad on top of the Guard for arming the system.