DVR / NVR - DVR is a security system device that records the video from up to 64 surveillance analog cameras on a hard disk. The frame rate can be switched from real time to time lapse in order to save disk space. Digital recorders are more flexible than earlier analog VHS tape systems, and the video can be easily transmitted over a computer network. NVR is a Network Video Recorder (NVR) is a digital device which sits on your IP CCTV camera to recieve live image/video streams and records them digitally to a hard disk. Quite similar to DVR but only serving the IP based camera.

Camera - Analog cameras are used most often in CCTV applications. Other examples of of Analog devices are security VCRs, switchers, multiplexors, and quads. CCTV systems that consist of Analog devices are considered Analog Systems. IP Cameras use the IP protocol, used by most LANs to transmit video across data networks in digital form. As its IP, video can also, but not necessarily, be transmitted across the public Internet, which allow homeowners and businesses to view their camera(s) through any internet connection available through a computer or a 3G phone. For professional or public infrastructure applications, IP video would always be restricted to within a private network or VPN.

Access Control - Access Control is any mechanism by which a system grants or revokes the right to access some data, or perform some action. Normally, a user must first Login to a system, using some Authentication system. Next, the Access Control mechanism controls what operations the user may or may not make by comparing the User ID to an Access Control database. Access Control systems include File permissions such as create, read, edit or delete on a file server, Program permissions such as the right to execute a program on an application server and Data rights such as the right to retrieve or update information in a database.