Comparing NVR Designs

The emergence of the NDVR — an NVR construct with several hybrid DVR features — has created a great deal of discussion and confusion among manufacturers, channel partners and end users alike. Why did they come into being, and what are they for?

The reason for the NDVR's existence is more evident; in larger and more complex video surveillance systems, the NDVR provides a unified, network-enabled platform for connecting all network cameras, routers/switches, video servers/encoders and capture cards. These devices can be accessed through a network, using client-server architecture, allowing remote access through any browser or server in the world. This enables remote monitoring as well as remote controls, for a network that is not quite like a DVR or an NVR.

The NDVR preserves the DVR's basic functions of recording and content management, while adding the NVR's advantages of Internet connectivity and remote storage. It also connects to analog cameras through video servers/encoders as well as network cameras. The NDVR enables long-term recording, remote monitoring and PTZ controls.

NDVRs straddle a blurred line between hybrid DVRs and pure NVRs, as the migration to IP continues. There is no doubt there is demand for DVRs with network connectivity or that NVRs enable more flexibility and are more future-proof. However, an NVR requires replacing all front-end devices and cabling with network cameras and Ethernet cables, driving up the cost of network-based surveillance. As hybrid deployments increase, NVRs are positioned as lofty and difficult-to-implement devices. Thus, the NDVR combines the advantages of DVRs and NVRs, contributing to its popularity.

NDVR APPLICATIONS
The NDVR's adoption of NVR advantages overcomes the limitations of DVRs. Network connectivity is the prime advantage, with the video management software (VMS) platform of NVRs being deployed for NDVRs. However, the NDVR supports analog as well as network cameras, much like a hybrid DVR. A crucial distinction is processing efficiency, with a Windows NT server or SQL server installed on the hardware to run the VMS. The NDVR is more of a NVR than a hybrid DVR with its NVR architecture, but adds the ability to integrate analog inputs.