One of the biggest areas of confusion within CCTV surrounds the decision on whether to fit an IP or an Analog based CCTV System. What are they and how do they differ?
IP CCTV uses your network which in a home or small business will be based around your internet router to constantly stream images from the cameras to an NVR or network video recorder. Each individual camera is assigned an internal IP address on the network as is the NVR. Power for the cameras is fed into the network by a power injector, this is known as power over ethernet or PoE. There may be a number of network connectors or switches and possibly a separate network storage device that holds all the footage.
You can use high-resolution cameras but there is a danger that as the number of cameras increases too much strain is placed on the network and frames start to drop off. Don’t forget that as well as the CCTV system your network will also be handling internet, streaming television, Netflix, video games, phone internet and so on. You also need to balance camera resolution with how long you are able to store footage.
One appeal of IP systems is the ability to integrate wireless cameras but there are some things to keep in mind. UK law dictates that the carrier strength must be very low and HD video is a complex signal which needs a good carrier. Walls and distance all serve to reduce signal strength and interference comes in many forms. There is a lot of stuff out there using the same frequency bands such as baby monitors, alarm systems and of course internet routers. You still need to power wireless cameras which will mean running cable.
Fixed lens wide angle IP cameras tend to be cheap and prolific but as we are constantly saying wide-angle spreads pixels rapidly and you soon become a small blob in the middle of the screen with no detail captured. Longer range IP cameras are less widely available and much more expensive so for outdoor use this is something to consider.
An IP CCTV system ends up being quite complex with several components having to talk to each other. The cameras will use a protocol that must be recognised by the NVR and the NVR needs to talk to the network as well as anything connected to it such as the data storage device, your computer, tablet, phone and so on. If there is a failure within the network then the CCTV won’t work. Fault diagnosis can be tricky if you aren’t an IT god and remote support is extremely difficult.
Some people think that if you want to remote access a CCTV system over the internet it must be IP based. This is not true. All our analogue DVR recorders allow remote access.
There is one other thing to consider with IP CCTV systems and that is data protection compliance. As a result of potentially huge fines GPDR rules have focussed attention on CCTV and one concern is the ability to tap into IP CCTV cameras on a network. People think about protecting the main access point to a CCTV system, the NVR or DVR but with IP CCTV each camera can be accessed fairly easily. Unless there is individual password protection to each camera anyone on the network could tap in and view the feed which would contravene ICO and GPDR regulations. With analogue CCTV this isn’t possible because the cameras are hard-wired directly into the DVR.
Traditional analogue CCTV is based around a DVR or digital video recorder with cameras hard wired to it using either coax cable or CAT5e / CAT6 ethernet cable. You only need a single cable running to each camera as this can also provide 12-volt power as well as transfer video signal back to the DVR. At CCTV42 we sell high definition analogue CCTV and it is our preferred solution.
Because cameras wire directly into the DVR no strain is placed on your network regardless of resolution. The only time you use the network is if you want to remote access the system and it will keep recording even if the network fails or phone lines are cut. Fault diagnosis is much easier as there are fewer components talking to each other.
Over the past few years, there have been significant improvements in analogue CCTV so it is now possible to get good quality high definition images. The one thing to watch out for with HD analogue CCTV is which protocol or language is used. We use HD-TVI cameras for a number of reasons but you can also get HD-AHD, HD-CVI and HD-SDI. Then there are a number of different resolutions. We use HD 1080P or 2.1 megapixels. Camera resolution is explained here on the website.
Our HD cameras come in a variety of lens options, not just wide-angle and it’s possible to get genuinely long optical range cameras without spending too much money.
One common misconception is that only IP camera systems can be remotely accessed over the internet. This is not true. All our analogue DVR recorders have the ability to connect to your network and can then be accessed within the property over the local network or from anywhere in the world over the internet using a computer, phone or tablet.
One potential advantage IP CCTV has is the ability to include cameras from other networks on your CCTV system. You could theoretically have a camera in another part of your building or even a different location on your CCTV system linked via the internet, but a word of caution. You are introducing even more links in the chain all of which have to be working in order for the system to work. We are firm believers in the adage "keep it simple".
Using analogue CCTV we would suggest fitting a local DVR recorder into which the remote camera or cameras are connected. This remote DVR records locally and doesn’t rely on the network to do so. If you want to view live camera footage or previously recorded material simply log into the remote DVR. We even have software that allows you to view live camera feeds from different DVR recorders anywhere in the world on the same screen. But regardless of network status, the cameras are always recording locally onto the separate DVR.
Using this method of remote DVRs provides an element of built-in redundancy and reduces the chances of total CCTV failure.
This is an extreme scenario for very large sites, in most situations it won't be applicable but we thought we'd throw it in just in case.