Hard Disk Drive / Primary Storage

A Hard Disk Drive (HDD) or hard drive is a data storage device that uses magnetic storage to store and retrieve digital information. It is often the primary data storage unit in a PC or computer Network.

The primary characteristics of an HDD are its capacity and performance.

Capacity is specified in unit prefixes corresponding to powers of 1000: a 1-terabyte (TB) drive has a capacity of 1,000 gigabytes (GB; where 1 gigabyte = 1 billion bytes).

Performance is specified by the time required or the speed at which the data is transmitted (data rate) to and from the HDD.

Direct / Digital Video Recorder Capability - Wired System (Analog Cameras)

A Direct/Digital video recorder is an electronic device that records video in a digital format to a hard disk drive, USB flash drive, SD memory card, SSD or other local or networked mass storage device.

The term includes direct to disk recording, portable media players and TV gateways with recording capability.

Personal computers are often connected to video capture devices and used as DVRs; in such cases the application software used to record video is an integral part of the DVR.

Network Video Recorder Capability - Wireless System (IP Cameras)

A Network Video Recorder is typically deployed in an IP video surveillance system.

Network video recorders are distinct from digital video recorders (DVR) as their input is from a network rather than a direct connection to a video capture card or tuner.

Video on a DVR is encoded and processed at the DVR, while video on an NVR is encoded and processed at the camera, then streamed to the NVR for storage or remote viewing.

Additional processing may be done at the NVR, such as further compression or tagging with meta data.

For integrating analog systems with the latest IP technology

A video encoder connects to an analog video camera and converts analog video signals into digital streams that are then sent over a IP-based network, such as a LAN, intranet or Internet.

It essentially turns an analog video system into a network video system and enables users to view live images using a Web browser or video management software on any local or remote computer on a network.

Contrast between wired NVR (IP cameras with wireless functionality) & DVR (Analog cameras with wired systems)