DVR vs NVR

DVR Security System – Pros & Cons

The advances in analog HD within the last six years have hugely reduced the gap in resolution between the two systems. You’ll notice that DVR based security systems are priced lower than NVR systems, with good reason. The lower price point is a great advantage of DVR based systems, but what are the negatives? We, therefore, need to break down each of the components of a DVR system.

Camera Type – Analog

The cameras used by a DVR system must be analog security cameras, better known as CCTV cameras. A large amount of the cost savings found by using this system is due to the camera. You can mix and match cameras, but there is less flexibility in the type of cameras you can use.

Using a DVR system, analog cameras stream an analog signal to your recorder, which then processes the images. An advantage of this system is in fact the reduced complexity that is required of the camera when in comparison to an NVR system.

Cable Type – Coaxial BNC Cable

Analog cameras connect to the DVR recorder via a coaxial BNC cable. The use of coaxial cable may not seem important, but it does have its limitations:

o  Coaxial cable doesn’t provide power to the camera. There are actually two cables included within one covering – a power and video cable. These cables separate each end to give the separate functions. Therefore, you’ll need to install your DVR near a power outlet.

o  Size and rigidity of coaxial cables make installation more of a challenge. Coaxial cable is wider in diameter compared to Ethernet cables used with NVR systems which can make it even more cumbersome to run cables in relatively tight spaces. Coaxial cables are more rigid, compounding this problem.

o  If your property has an existing coaxial connection for a previous security system, then you can use the same cable to connect your new system.

o  The standard coaxial cables don’t have support audio.

o  Image quality on the coaxial cable will begin degrading after about 300ft/90m, which ultimately will limit the ability to which you extend your security presence. The low-quality cable will lead to a signal loss at shorter distances.

Recorder

DVRs depend on a hardware chipset known as an AD encoder that is responsible for processing raw data streaming from the camera into legible video recordings. DVR systems have different necessities when it comes to the recorder. Basically in a DVR system, the user has to connect every camera directly to the recorder. In comparison, NVR systems only require that every camera connects to the same network. In a DVR system, the power to the cameras isn’t provided by the recorder. Every camera connection needs a splitter that will supply power to enable camera functionality.

System Flexibility

DVR security systems have less flexibility compared to their NVR counterparts in terms of the camera type and mounting options. Whereas NVR systems can integrate both wired and wireless security cameras, DVR systems only use wired security cameras. DVR systems have fewer flexible mounting solutions. That’s because routing coaxial cable can be more challenging in tight scenarios and power outlet is needed for each camera.

Image & Audio Quality

So far through this read, we have learned that in DVR systems the cameras transmit analog video via the coaxial cable directly to the recorder then images are processed. The analog signal will result in a lower quality image in comparison to NVR systems. Coaxial cables don’t natively transmit audio signals, and DVR recorders have limited numbers of audio input ports.

NVR Security System – Pros & Cons

NVR camera systems incorporate the newest tech to create an enhanced, feature-rich security system. Known as POE security camera systems, NVR based systems are flexible and complex in contrast to DVR systems.

Camera Type – IP Camera

NVR systems process video data at the camera rather than on the recorder. The cameras in NVR systems are more robust than their DVR counterparts. NVR systems use IP cameras - standalone image capturing devices. Every IP camera has a chipset capable of processing video data which is then transmitted to a recorder. In contrast to analog cameras, IP cameras are all capable of recording and sending audio. More powerful hardware on IP cameras also enables improved smart functionality and video analytics, like facial recognition.

Cable – Ethernet

NVR systems connect the camera to the recorder, in a similar fashion to DVR systems. However, the connection from the camera to the recorder is entirely different. NVR systems use Ethernet cables to transmit data i.e. cat5e and cat6. We prefer Ethernet cable due to a variety of advantages in comparison to coaxial cables:

o  Ethernet cable will power the camera using Power over Ethernet (PoE). In simple terms, it means your camera needs one cable running to capture video, audio, and power the camera, therefore eliminating messy splitters like a DVR system.

o  Ethernet cables tend to be much easier to route and terminate. This is because it’s thinner and has smaller connectors, therefore less drilling.

o  Ethernet is cheaper than coaxial cable and readily available, making cable replacement or system expansion accessible and affordable. Many modern homes and businesses are being built wired for Ethernet, making installation much easier.

o  An added advantage of using Ethernet cable is that every camera can transmit audio since Ethernet sends audio data natively.

o  Cables don’t need to be routed between every camera and the recorder. They only need to be on the same wireless network. Installation is straightforward and cleaner as multiple cables aren’t needed.

o  Despite a shorter max Ethernet cable length, 328ft or 100m, network switches can be extended without affecting image quality.

Recorder

The recorder in an NVR system doesn’t process video data, unlike a DVR system. That step is completed at the camera before transmission. NVR recorders are used for storing and viewing the footage.

System Flexibility

NVR systems are more flexible because security cameras don’t have to be physically connected to the recorder. Instead, IP cameras only have to be on the same network. You could feasibly have cameras anywhere in the world on the same network that connect to your NVR can then be viewed as one.

Image & Audio Quality

NVR recorders receive a pure digital signal from the cameras resulting in HD video quality compared to a DVR at the same resolution. More on that, Ethernet cables have audio transmission. This means the cameras with microphones can record audio to the NVR.

In Summary – DVR vs. NVR System

Both systems are reliable in recording video data. Although in the past the video quality of DVR systems lagged behind in comparison to NVR systems, today the gap is being closed. The difference between DVR and NVR systems comes down to cost, how data is transmitted, and the type of cameras. NVR systems tend to have much better picture quality, easier installation, increased flexibility, and native support for audio on cameras that have a microphone. NVR systems tend to be quite a bit more expensive in comparison to DVR systems - an important consideration for the budget-conscious consumer.

Anyone in search of a relatively straightforward security system, a DVR system is sufficient, especially if your property is already wired for a coaxial cable from an existing security system. If you are in need of a top of the line, very flexible solution, an NVR based system will be best. The deciding factor will be based on the specific security needs of your property.