An NVR (Network Video Recorder) is an IP-based recorder that operates independently from a PC or other operation systems. Aimed to store digital video streams from network cameras, an NVR is usually incorporated with a large-volume hard disk to allow for a long period of recording.

An NVR differs from a traditional DVR in its network connectivity, which allows digital data to be transmitted to other networked devices over the Internet. Another difference is that an NVR can be directly connected to a network camera while a DVR is usually be connected to an analog camera.

in practice, an NVR is the heart of a sophisticated surveillance system featuring multiple feeds from wireless cameras strategically mounted around your property or properties. Many allow you to view in real time, store, retrieve, search, etc., and feature crystal-clear, high-resolution imagery. Frame rates up to 30 frames per second ensure that your video feed is smooth and natural looking. Choppy and grainy black and white video is very much a thing of the past. These types of high-end systems are usually most appropriate for large places of business, where security isparamount and many sensitive areas—indoors or out—require constant coverage. Some NVRs also allow audio recording and other features

An NVR is distinct from a DVR in that its inputs—from any number of surveillance cameras—is obtained from a network, rather than from individual feeds. This means that each individual camera in the network is assigned a specific IP (internet protocol) address, which the NVR recognizes and accepts. These addresses are unique, so your NVR knows exactly which camera is supplying feed from a given IP address. Unlike a DVR, which needs to be onsite, an NVR is capable of recording and managing feeds from cameras, no matter where in the world they may be located. The video feeds reaching an NVR are transmitted over the internet, so there’s no physical distance limitation. This would allow a business owner to monitor and manage feeds from multiple locations, for instance. It also makes it possible to store imagery at an offsite location, for an additional layer of security.