Video management system

A video management system, also known as video management software or a video management server, is a component of a security camera system that in general:

A VMS can be the software component of a network video recorder and digital video recorder, though in general a VMS tends to be more sophisticated and provide more options and capabilities than a packaged NVR device.

Due to improvements in technology, it is necessary to make a distinction between a VMS and the built-in features of modern network based security cameras. Many modern network cameras offer internal capabilities to record and review video directly themselves via a web browser and without the use of a VMS. However a camera's built-in web interface is typically exclusive to the camera itself and does not normally provide a shared access capability across other network cameras.

Optionally, a VMS may also provide additional features and capabilities. The extent of these capabilities may be divided across several product tiers, with the lower cost VMS products having fewer features.

Rather than continuously recording data, a VMS may also implement motion detection to reduce the amount of data to be recorded.

In older analog security camera systems, the cameras were "dumb" devices only capable of producing a video signal continuously, and any video signal processing had to be done by the recording VMS. With modern megapixel network cameras, the cameras are much more sophisticated.

Motion detection can now be distributed, so that the cameras do motion detection themselves and only send video when motion is detected.

Alternately, motion detection can still also occur in the VMS. Some VMS do not have motion detection and rely exclusively on it being done in the camera.

A difficulty with modern megapixel network cameras is the variety of standards and industry compliance with those standards. If a VMS does not have built-in motion detection, and a camera that is only accessible via ONVIF does not expose a motion control interface, and the camera manufacturer has not provided a custom API to the VMS authors, then motion detection will not be possible even if the camera is theoretically capable of it.

For a very large and complex security camera system, there may be too many cameras, too much network bandwidth, too much data to be analyzed, or too much storage required for a single server device to handle the workload.

In this case the workload is divided across multiple server devices, each handling a slice of the overall workload.

The VMS provides a single management interface allowing clients to access camera sources across all servers, making them appear to be a unified collection rather than isolated on multiple independent sources.

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