NAS box, absolutely.
I have a 4 bay Qnap
TS-453a.
Built in functionality and application for receiving video from IP cameras.
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Comprehensive surveillance solution providing 24/7 security
Surveillance Station is a professional network surveillance Video Management System (VMS) that offers a user-friendly management interface, over 3,000 compatible IP camera models, and expandable IP camera channel licenses. It supports real-time monitoring, video & audio recording and playback with a wide range of customizable settings. You can also install the Vmobile app on your iOS® or Android™ devices to manage monitored channels anytime and anywhere to safeguard your office environment, or install the Vcam mobile app to turn your device into a network camera to instantly record to your TS-453A. The TS-453A includes 4 free IP camera channels and you can expand up to 40 channels by purchasing additional licenses.
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I'm not saying buy that particular model, but just as an example of what comes with these things.