A Network Video Recorder (NVR) is a complete IP video surveillance system that uses dedicated hardware for video capture. It records video, audio, and saves it to the recording medium such as a hard drive. You can playback footage on the NVR later. You also can access live video and images from the NVR.
NVRs are seen as the successor to digital video capture cards. As NVRs offer more flexibility, such as remote management over the Internet. They come with other benefits, including better viewing and recognition of faces and license plates.
How NVR Camera Systems Work?
There are three components in an NVR camera system: a network, cameras, and NVRs. All of these parts work together to function as one system.

Network video recorder systems are newer than the traditional security camera system. The benefits of recording and storing digital data which is more convenient than an analog Digital Video Recorder system (DVR), is what makes these systems so popular.
An NVR system consists of IP cameras that encode and transfer video footage over a WiFi or wired connection to the recorder. In a wireless network, the camera still needs to be connected to a power source, and video is transferred over WiFi. The wireless camera is NOT a wired-free camera. In a wired camera system, the power and video can be transmitted over one single cable by using the PoE (Power Over Ethernet) technology.
Let’s take a look at how three components of an NVR camera system work together
NVRs: Video is received over the network in the form of data, and is stored for later review. The NVR comprises corresponding Ethernet ports which can connect to multiple IP cameras on one side.
Cameras: The camera captures the image and digitalized it before it sends it to an NVR. In general, an IP camera must connect to the NVR via either Ethernet or Wi-Fi, although wired connections give a more reliable video feed than wireless.
Network connection: If you have a wired Ethernet connection, use an Ethernet cable to connect it to the NVR. For a wireless connection, you will need to configure your settings on the IP camera. As there is no screen to input the WiFi password like on your mobile phone, the connection could become a mess, especially if you are working with a WiFi mesh network.
What Are the Types of NVRs?
Network video recorders can be generally classified by whether they have PoE ports or not.
PoE NVR: This type of NVR has a PoE switch integrated into the box. All the cameras will be attached to the PoE ports at the rear of the NVR, and the NVR can provide both power and data exchange with all the cameras at the edge. The camera needs to be PoE compatible, there is no need for a power source present at each of the IP cameras.

Non-PoE NVR: A non-PoE NVR does not have any ports for cameras to plug into on the back panel and instead requires a separate power adapter for cameras to function. However, this can be solved with an independent PoE switch to supply the power and data exchange to each of the cameras.
According to the number of channels:
The number of channels of NVRs can be divided into 4, 8, 16, or 32, 64. These channels refer to the number of supported cameras. If you are just building a basic video surveillance system, 4 or 8 channels will be enough. They are the best option for homes, retail stores, or small office applications. 16 channels are better for large buildings and factories. If you need more devices, but also need to consider budget constraints, 32 channels are recommended.
Features of NVR Systems
There are many features of NVR systems, Some of them are listed below.
- NVR systems can record both video and audio.
- This leads to improved image quality over CCTV cameras.
- NVR systems provide higher image quality than traditional DVRs
- multiple lenses IP camera lets you cover more areas with a panoramic view.
- NVR can be wired or wireless.
- You just need only one cable for the video, audio, and power.
- NVR systems have the ability to identify faces, license plates, etc. due to high image quality.
Let’s answer some of the command questions below.
Will there be a video lag on an NVR camera system?
No lag should not be experienced on an IP camera system if the installation is correct. You will need to make sure that your NVR supports the cameras you want to connect, and it can handle the bandwidth and video quality. That being said, there may be some small lag in a properly designed network, but it should be minimal (0.5s or 1s). If you notice any lag after that, inspect your network for any bandwidth bottlenecks.
Does an NVR system consume more bandwidth than a DVR system?
The answer is that it doesn’t matter much, as long as the system is aware of all the recordings and saves. An NVR with a built-in PoE will have each camera connected to the back of the NVR, so the network stays unaffected. External PoE switches that are placed on a separate network will not affect the network at all.
Moreover, remember that NVR systems do not need to use the internet to save and store footage. You’ll only consume bandwidth when you connect to these systems remotely using your phone or computer——which really doesn’t matter since both systems use similar amounts of bandwidth. Additionally, these systems will only use substream mode when being accessed remotely, which has a lower bandwidth than mainstream mode.
What Cable Do I Need for a Network Video Recorder?
When it comes to wiring a PoE camera to the back of an NVR or PoE switch, Ethernet cabling is a good option. It provides power, audio, and video over one cable. Ethernet cabling comes in different standards. We recommend using CAT5e or CAT6. If you are getting the long run, it is important to choose the 100% pure copper-made cable. The CCA-type Ethernet cable causes serious power loss. The distance between the camera and PoE NVR is limited to 100 328ft (100 meters). You will need a PoE extender to extend the distance beyond 100 meters.
Can NVR Work Without Internet?
An NVR can be used without connecting it to an internet connection. However, NVRs offer features like remote viewing, and not being connected to the internet can make these features unavailable.
The recorder will still store video content, but you’ll have to watch at the site of the NVR which may defeat the point of having installed an NVR.