NVR vs. DVR

Summary: A DVR is a great choice for budget-minded folks wanting a large fleet of wired cameras and straightforward continuous video recording.

A digital video recorder (DVR) connects to security cameras using an analog video cable. It sounds fancy, but an analog video signal is just a series of electrical pulses representing light waves hitting your camera’s lens. Like the human eye, light enters the camera, and it’s translated into electricity. But instead of an optic nerve, those pulses travel through a coaxial cable to the DVR for conversion into a digital video file.

Analog video is an old technology, but this makes it an affordable option for video surveillance that generally works well in multi-camera security systems.

But it has some limitations:

• Power and video require separate cables. If you look closely at the back of an analog camera, you'll notice two connections: one for video and one for power. While most analog cameras bundle these with a combined cable, you still need a separate power adapter because the DVR security system can't power the camera through the video cable.
• The analog signal's power drops with distance. The longer the cables, the more the signal decreases. So cables 300 feet or more won't work as well.¹
• There's no audio. With an analog security camera, there's no way to add audio to the video feed without running yet another cable. Some DVRs and analog cameras offer audio connections but don't have enough audio ports for every camera.

Summary: The NVR is a superior option for tech gurus who are fine spending extra for a feature-rich wired or wireless camera system.

A network video recorder (NVR) receives preprocessed video files from IP cameras over an Ethernet cable or wireless connection. With NVRs, IP cameras prepare the video files before sending them to the NVR for  . This is different from .

Think of it this way: Analog cameras send the raw ingredients of a cake and the DVR bakes it. While IP cameras make the cake for the NVR to store like a refrigerator.

Ethernet cameras are the most popular IP camera used with NVRs because they use Power Over Ethernet (PoE). This means your surveillance camera gets everything it needs from a single cable that plugs directly into the back of the NVR: video, power and audio.

Because NVR cameras have built-in processors and advanced hardware, they can send more information than an analog video feed. It's much easier to find NVRs and accompanying IP cameras that support audio recording, two-way audio, and smart motion detection that can differentiate between people, cars, and animals.

Plus, the video data is less susceptible to interference. As long as all the ones and zeros of the video file make it to the NVR, the video quality won't degrade. Although the physical signal strength decreases with distance, like on analog cameras, you can renew the signal as it passes through Ethernet switches.

Unlike the specialized coaxial cables on a DVR, an NVR works with PoE-compliant CAT5 Ethernet cables readily available at your local hardware store.