You require a computer with a minimum ,
- 64-bit Windows 7+
- Intel® Core™ i7 +
- 32 GB+ RAM
- 6GB +Nvidia Graphic card ( however 6GB can support up 3-4 Camera Maximum) (Please see list of Compatible GPUs)
- Possibly PLC ( Programable Logic Controller ) this is depends on your the Door/Gate/Bollard/whether if they manufacture does provide SDK ( Software Development Kit)