Commercial CCTV systems are available from a number of manufacturers in differing configurations to suit the needs of companies big and small – and one of the first choices a purchaser normally needs to make is whether to opt for a ‘DVR’ or an ‘NVR’ system.
DVR stands for ‘Digital Video Recorder’ while NVR is an acronym for ‘Network Video Recorder’. The terms refer to the type of recording technology used. DVR systems are traditional local storage devices – i.e. footage recorded by directly connected analogue cameras is processed and stored within the central unit. These systems are usually cabled, and the technology used is very similar to consumer devices like the Tivo.
By contrast, NVR systems could be described as ‘internet storage’ devices. They are typically used with internet protocol (IP) cameras, which process their own footage and then transmit this wirelessly over a defined network to a recording system. From there it can be viewed or accessed remotely. NVR system cameras use cabled ethernet connections but their cameras can also operate entirely wirelessly, a feature that allows considerable flexibility in layout and installation.
Which type of commercial CCTV is right for you? Well, that depends. If your requirements are relatively uncomplicated and suitable coaxial cabling is already in place, a straightforward DVR installation may be all you need for your business or office. But if comprehensive coverage is a priority, your premises are larger or there are multiple sensitive areas on site, a more modern and flexible NVR system is most likely the right choice for you.
Let’s take a look at the differences between DVR and NVR systems in more detail.
Typically, commercial DVR security systems are less expensive than the NVR equivalent because they use well-established technology.
They generally offer a similar camera resolution to NVR systems. The overall image quality is likely to be lower but the gap has narrowed considerably in recent years: even analogue cameras have benefited from advances in camera technology.
DVR systems use BNC coaxial cables similar to those paired with other audio-visual equipment. Coaxial cables are thicker and less flexible than ethernet cables, so it can be difficult to install them in areas where space is limited. They also do not provide power, which means the camera must be stationed within reach of a power outlet and a power line fitted to the camera alongside the coaxial cable. Sometimes the two cables are bundled together and separated at the end via a splitter.
Coaxial cables do not support audio so this must be sent down a separate RCA cable. Multiple camera set-ups can pose a problem here because DVR recorders only feature a limited number of audio ports.
Finally, coaxial cabling can only transmit high quality imagery over a limited distance – about 90 meters, limiting expansion options.
NVR systems represent the latest and greatest in multifunctional business CCTV.
Their greater sophistication starts with the IP camera. Video footage is processed via an onboard chipset before its transmission to the recording device, and these cameras feature full native support for audio via built-in microphones. Digital footage is accessible via the cloud and can be analysed in a more sophisticated ways: for example, facial recognition algorithms can be used to identify individuals, enabling access control to specific areas or even your entire premises.
Ethernet cabling offers a number of significant advantages over the coaxial equivalent:
- It can provide power to connected cameras while transmitting audio and video, so no awkward additional power line is needed.
- It is thinner and more flexible, with smaller connectors, making installation easier.
- It is generally cheaper, making any subsequent expansion of a security network more feasible for business operators.
- Network switches allow ethernet cabling to be extended for longer distances with no loss of image quality.
For informed advice, discuss your specific needs with a security system expert today.