CCTV has come a long way. Today security cameras are affordable and a great addition to homes or businesses. In fact, these days the features they offer they act not just as surveillance but as an alarm security system. Having been in the security business, as well as a business owner, I would strongly recommend some type of video surveillance system for both your home and business. But it can be confusing selecting the right system. You may have come across the terms NVR and DVR and wondered what they are and what you should choose. In this article, we break down what an NVR and DVR do, where they differ, and the pros and cons of each: NVR vs DVR: what is best for video surveillance?
Video Storage and Access
For security cameras to be useful, they have two basic requirements: the provision to view the camera footage and the ability to store the camera footage. In most cases, especially in businesses, the video footage is stored on servers which also allows the cameras to be viewed. These are basically hard drives (with some bells and whistles) that are connected to your camera system and allow you to access the footage. Typically, these devices come in two varieties: NVRs and DVRs.
The core purpose of DVR and NVR systems is the same: video surveillance. But, it’s important to know the difference between NVRs and DVRs, especially if you are considering installing a security camera system in your home or business. Each has its pros and cons. Which you select will affect the video quality and amount of footage stored as well as your costs.
I have installed both DVR and NVR systems over the years, so in this article, I will summarize the difference between the two and their pros and cons.
Why you need a DVR or NVR
If you have a security camera system, you need somewhere to store the video footage. After all, the purpose of a security system is to capture events on video so that you can play them back at a later date. You may even have to export the video and share it with the authorities as evidence. And this is what a DVR and NVR allow. Both store video. And both will allow that video to be accessed easily for later reference.
Both Digital Video Recorders and Network Video Recorders are leaps ahead of older technologies that relied on tapes, CDs or DVDs. Instead, DVRs and NVRs use hard disk drives, often several of them, to store video from multiple cameras and allow easy access to the footage both in real-time and later on.
However, the manner in which the two transmit, communicate and store video is significantly different. And, this has implications for installation costs, access options, video quality and any more advanced options. So next, we will look at how these technologies work and the difference between NVR and DVR systems.
What is a DVR (digital video recorder)?
DVR stands for Digital Video Recorder. These are an older technology than NVRs. They also tend to be cheaper.
The main components of a DVR are:
- Analog cameras. These cameras transmit raw video data.
- Coaxial BNC cables. These connect the analog camera to the DVR and transmit the raw video.
- Camera power cables. Each camera requires it’s own power source.
- Digital Video Recorder. This is the processor that encodes the raw video to digital format and stores it on hard drives for access.
DVR systems connect HD or analog CCTV cameras to the main recording unit using coaxial cables, allowing for secure video recordings. Analog cameras do not process the video so the coaxial cables transmit raw video from the analog cameras to the DVR.
Coaxial cables do not transmit power either, so each camera requires it’s own power cable that runs to a transformer at an electrical outlet.
Coaxial cables also do not transmit audio. This means a separate RCA cable has to be run back to the DVR if audio is to be recorded at the site of a camera that has a mic.
Once the raw video has been transmitted to the DVR, the DVR encodes the video into a digital format. This enables the video to be stored and accessed and allows other more advanced features to be deployed (like motion detection zones, scheduled recording, etc).
There can be multiple cameras running into the DVR. DVRs will commonly come as 4-, 8- or 16- channel systems with each channel providing video transmission for one camera.
What is an NVR (network video recorder)?
NVR stands for Network Video Recorder. NVR security camera systems are the current preferred choice due to their advanced technology, and ease of installation.
An NVR system typically incorporates the following components:
- IP cameras. IP stands for Internet Protocol and means these cameras are addressable and accessible on the network. The IP camera itself will encode and process video taken. Then that video signal is sent to the NVR An IP camera is either wired using PoE (where video, audio and power are run on a single ethernet cable) or wireless (where video and audio are transmitted across the WiFi network)
- Ethernet cables. By connecting Ethernet cables to PoE cameras and the NVR, you can transmit data such as audio, video and power reliably through a single cable.
- NVR recorder. By encoding video before it reaches the recorder, an NVR fulfils one primary role – that of storing and allowing access to the footage.
NVR systems employ IP cameras to capture footage and compress it into digital data, sent either wirelessly through WiFi or by a wired connection. Wireless setups feature IP cameras linked up to an electricity source with video transmitted over the airwaves. Whereas, in wired solutions, POE (Power Over Ethernet) cables are used directly connecting the recorder; providing both power and signal simultaneously from its origin point. An IP camera also offers greater options for analysis like motion detection and person, vehicle or animal detection using AI (artificial intelligence).
What are the Pros & Cons of DVR & NVR Systems?
Because digital video recorder and network video recorder systems use different communication methods, there can be significant differences in the cost of installation, maintenance, video quality, storage capacity and the available advanced options for end users. Understanding these will help you decide which best suits your needs and budget.
Advantages of DVR vs NVR
Despite being older technology, there are a few advantages to DVR systems that are worth cosnidering.
Lower cost upfront
Because of their simpler design, analog CCTV cameras are generally more cheaper than IP cameras – except if you’re looking for a high-resolution one. As such, the initial installation costs of DVRs tend to be much lower when compared with other camera systems.
Camera compatibility
Unlike NVR systems, DVRs provide the advantage of being able to utilize a variety of analog security cameras from different manufacturers. This can be incredibly cost-effective if you ever need to replace one, as it eliminates having to buy another camera from the same brand.
Disadvantages of DVR vs NVR
You may already have gathered from the description of how a DVR works from above that there are some considerable shortcomings to DVR systems.
Running cables
Setting up DVR systems often proves trickier than NVRs since the coaxial and power cables are thicker and less flexible. Squeezing them into tight spaces can be difficult. And, unfortunately, DVRs do not play well with wireless cameras. However, if you already have pre-installed coaxial cables, then configuring a DVR system should be simpler.
Cable Length Limitations
Generally, an analog camera should be connected to no more than 300 feet or 90 meters of cable in order for the video signal not to deteriorate.
Lower-quality video
Analog cameras and coax cables have certainly improved, but their quality cannot match the video resolution or frame rates that NVR systems offer. Coax cables generally possess restricted bandwidth, leading to a 4CIF resolution (704×480) with 7-15 frames per second. There are some newer analog HD systems providing 720p or 1080p video clarity but these are not common. DVR-quality video may be adequate for security recordings, but enhanced processing using analytical software or AI will be limited (e.g. license plate or face recognition tracking).
Limited audio capabilities
Audio transmission requires an RCA connection. But, DVRs usually have very limited audio inputs, and that means the number of cameras that can capture sound is limited.
Lower coverage area
DVR coverage is usually limited by the wire runs. Analog cameras runnign on coaxial cable should not exceed 300 feet from the DVR box. Plus, the cameras must usually be close to power sources.
No network connectivity
DVR systems aren’t connected to a network by default, which means you can’t remotely access or manage your security footage unless network access is set up, and that usually requires some technical know-how.
Limited supply
Due to the fact that many vendors have ceased production of this older technology, supplies are dwindling and maintenance costs are rising.
Advantages of NVR vs DVR
Overall the benefits of NVR systems are significant. But when deciding on a system, you should make sure that any benefits are applicable to your circumstances. So it’s important to understand the advantages that an NVR offers and whether these are suitable for your application.
Video image quality
IP cameras offer higher-quality video, typically between 2MP (1080p) to 12MP (4K) with a frame rate of 30 fps (real-time video)—much better than the image quality of analog video in in DVR systems.
Wiring installation
Wired IP cameras require a single ethernet cable for each camera. This makes installation much easier compared to coaxial cable required in the installation of analog cameras. Ethernet cables are more flexible and less rigid than coaxial cable.
Power over Ethernet
The ethernet run to and from IP cameras can also often provide power. Again, this means fewer cables have to be run than with a DVR because analog cameras require separate power wires to be run in addition to the coaxial cables for every camera. That’s money and time saved. There are siamese cables. These have the power cable attached to the coaxial cable. This reduces the number of cable runs, but the wires are still less flexible and more difficult to run than ethernet.
Easy wireless options
Because the cameras simply require access via the network, wireless WiFi cameras are easy to incorporate with an NVR and wireless router or access point. And this adds the benefits of reduced wiring and easier camera installation
Flexible camera placement
With the availability of wireless cameras and PoE extenders, it has become easier to install cameras in any place desired. Wireless IP cameras can now be conveniently placed outdoors with minimal effort.
Network connected
NVRs are network-ready. That means they are easily accessible both from within the network and remotely across the internet from web portals or smart devices using secure access and protocols.
Audio included
The ethernet cables can transmit audio with the video. The audio data is encoded along with the video data at the camera. No extra cables are required, and each camera can record audio whereas a DVR usually has a limited number of audio inputs.
Greater distance covered
It is suggested that your PoE devices should not run for more than 328 feet or 100 meters. But the beauty of ethernet is that you can extend the distances with PoE extenders, network switches and hubs. Even with wireless IP cameras, WiFi extenders can allow signals to be received from much greater distances than typically possible with a WiFi router or access point.
Video analytics
Another significant advantage of NVR systems is the greater number of video analytics offered. There are growing options to track and record events, objects, people, animals, and decipher patterns, making NVR systems “smart.”
Cloud-based storage options
Because of the network-based nature of NVRs, many can be integrated with cloud-based (internet) storage. This can reduce the dependence on local storage and opens up options for offsite storage and backup of recordings. Doing so is a lot more difficult with DVRs.
Disadvantages of NVR vs DVR
NVRs are newer technology and the number of devices and the bells a whistles available and marketed can be enticing. But, you also need to consider the drawbacks to NVRs. These include:
Lower security
NVRs can pose security risks. Because of their networked nature, unapproved access is a possibility. If you have limited network security, it’s possible to hack into your system. So pay attention to your network, passwords, etc.
Camera compatibility
If you don’t purchase IP cameras from the same manufacturer, it can be difficult to get multiple compatible ones that will work with a single NVR system.
Lower life span
The average lifespan of most NVR system components is only 3-8 years, and certain parts such as hard drives have a significantly shorter life expectancy.
Greater upfront cost
Despite the many advantages of NVR systems, they can be costly when compared to other technologies.
Common Questions About NVRs and DVRs
There are some frequent questions that crop up about DVRs and NVRs. We try to answer some of these below…
Is an NVR more reliable than a DVR?
Yes, an NVR is generally more reliable than a DVR. This is because the video data is encoded before it reaches the recorder in an NVR system. Conversely, in a DVR system, raw video data needs to be transmitted from the camera to the recording unit via coaxial cable. The encoding provided by an NVR also helps reduce bandwidth requirements and makes it easier to store more video on one device compared to a DVR. Additionally, since most of today’s internet protocol cameras are backed up with advanced functions like motion detection and scheduled recording at no extra cost, this adds another layer of reliability for both personal and business use.
Can I use NVR without Internet?
Yes, you can run an NVR system without having internet access. If your internet connection is down, an NVR camera system will still function and record and store video. However, you will not have remote access to view the footage, because that will require internet access. Instead, you will have to view footage within the same local network. For example, if your NVR device is attached to a router or switch, then even without the internet, you can access the recordings and settings on a computer or smart device also attached to that router.
What about cloud cameras?
Cloud-based security cameras have become incredibly popular in recent years. These are IP cameras that use cloud computing (the internet) to store and manage recordings. They usually have a dedicated smartphone app or web portal for users to remotely access the recorded footage. And this can be done anywhere in the world, as long as they have an internet connection. This offers huge convenience for homeowners.
One of the biggest advantages to using cloud cameras is the ability to access footage from multiple devices and locations. So, you can access your cameras from home, the office, or even halfway across the world. With cloud storage, you can view recorded surveillance footage from anywhere with an internet connection.
There are a couple of drawbacks with cloud-based security cameras.
- Cost. Unlike most traditional DVR or NVR systems, cloud cameras will require a subscription. This means access to recordings and settings will cost you. This can add up over time, especially if you have multiple cameras in your home or business.
- Internet required. Because the recordings are stored in the cloud, you can’t access them if there is an internet outage. This could be a major downside for businesses that rely on 24/7 surveillance coverage. For this reason, NVR and DVR systems may still be the preferred option for most businesses that require uninterrupted coverage.
- Security and Privacy. Because your recordings and access to cameras are provided as a service, the security risks and privacy issues are increased. Make sure you use adequate security measures like 2FA and secure passwords.
Cloud-based options with NVR
An NVR is closely tied to networking services. This means most NVRs can use cloud storage capabilities for video surveillance data. This will help reduce the load placed on local storage capacity but also can act as a fail-safe backup of sorts if local footage is lost. DVRs however, do not have access to such cloud services.
Can I view DVR cameras on the Internet?
Yes, you can view DVR cameras on the internet. Most modern DVR systems come with a web interface that allows users to access their recordings from anywhere in the world. However, this may require some technical know-how like port forwarding and setting up a DDNS (Dynamic Domain Name System) in order to remotely access the camera’s settings and live-streaming video. If you don’t have the technical skills or knowledge, you may want to hire a professional to help set up your system.
NVRs on the other hand will typically be “internet ready” out of the box, just requiring plugging into your network/router. The options for viewing and accessing video recordings and live footage will also depend greatly on your DVR brand since the video comes from analog cameras. This means the DVR does all the heavy lifting. The DVR will process video data at the recorder, rather than receiving pre-processed video data from the cameras.
What’s the average cost of a DVR vs NVR?
The cost of a system will partially depend on the number of cameras to be installed, whether cabling has to be run (and how much of it), as well as the brand. Generally speaking, the equipment cost of an NVR will be higher than that of a DVR. But there will probably be savings in the labor to run NVR cabled. DVR systems are more budget-friendly on equipment since they employ older technology analog CCTV cameras. Whereas, NVR systems offer advanced capabilities with digital IP cameras, and those are more expensive.
Geovision offers a large lineup of NVRs but also the older tech DVRs that I have worked with. And I can recommend systems from Amcrest, Lorex, and Reolink,
The Final Score- NVR vs DVR: what is better for video surveillance?
So hopefully you have a better understanding of why an NVR and DVR system are required, how they basically function, and what the pros and cons are of each. But you may still be wondering which of these surveillance systems you should go with, a NVR or DVR.
If you have existing analog cameras that are wired, you may consider a DVR because of the ease of install and cost saved. However, for new installs, I would personally shy away from DVR technology with their lower quality, analog cameras. Having personally seen the added benefits of easy remote access, improved video quality, helpful advanced features and the far simpler wire runs offered with NVR, that’s what I would recommend for both home and business installations. Additionally, NVRs can accommodate wired or wireless cameras. But for simple home security camera installs where you have stable consistent internet service, I would also recommend you look at wireless camera systems like those from Arlo or Reolink.
Be smart and stay safe.