Digital And Network Video Recorder (DVR and NVR)

eSSL Security

NVRs (network video recorder) and DVRs (digital video recorder) are used to record, manage and store surveillance videos so that videos can be reviewed later.  These are available with a variety of software and hard drive sizes. Both NVR and DVR do the same job of saving and storing videos from surveillance. However DVR is used for analog camera and NVR is used for IP camera.

How DVR and NVR works?

DVR or digital Video Recorder is a consumer electronic device that records video in a digital format to a disk drive, USB flash drive, SD memory card or other local or networked mass storage device. Older systems would record video directly to tapes using a VCR; modern systems use DVRs to convert video files into digital formats, allowing you to store more videos. A digital video recorder configured for physical security applications record video signals from closed-circuit television cameras for detection and documentation purposes. Many are designed to record audio as well, whether at the camera or as a separate apparatus in an isolated area. DVRs have evolved into devices that are feature rich and provide options that exceed the simple task of recording video images that was previously done through VCRs. The DVR provides a convenient, if limited, replacement for the multiplexer + VCR combination and provides non-linear access to recorded material usually selected by camera ID, time and date. The consistency of quality of recorded material will in general be higher than that obtained with analogue tape although the actual quality achieved may or may not be better, depending on the compression algorithm and individual configuration.

NVR or Network Video Recorder is used when you have IP Cameras. The most obvious difference between the DVR and NVR is that whereas the DVR records from analogue streams provided from analogue cameras the NVR records video streams that have already been encoded at the cameras. This will typically be in either MPEG-4 or H.264 formats which have enjoyed widespread adoption in the CCTV industry as the compression technology of choice, due largely to their efficiency. These recording devices use the local network to send and receive data, and are ideal for remotely monitoring your surveillance system from your computer, smart phone, or tablet. Unlike its predecessor, the DVR, a NVR is not limited to be in the same area as your cameras cabling to one section. The unit can be placed virtually anywhere, it simply just needs to be on the same LAN network as the IP based cameras.