CCTV
DVR or NVR: which CCTV recorder do you need
The difference between a DVR and an NVR, why the recorder decides your cabling, and how to size the hard disk for the retention you actually want.
CCTV
IP camera or analog CCTV: which to buy
IP and analog HD cameras compared for Indian homes and shops — cabling, cost, image quality, and when the cheaper option is genuinely the right one.