Coaxial cable

Analog Vs. Digital

Network IP Cameras have been around for at least a decade now. Only recently have cabling installers began to pay attention to the technology because surveillance cameras have traditionally run on separate coaxial cable. Around 10 years ago, the fist digital IP camera connected directly to a data network which changed the future of the surveillance camera industry.

During the early stages, the technology was not as professional as analog cameras. Most cameras were seen as ‘web cameras’, which were used to view objects or events over the internet or a LAN. Because of this perception, many users directed their investment to analog technology and decided to digitise video by other methods.

To bridge the ‘gap’ or to digitize the analog signal many people installed digital video recorders (DVR’s). DVR’s typically add digital recording to an analog camera system by replacing VCR’s with DVR’s. A problem with DVR is that compression is done at the DVR level, so it is difficult for it to handle inputs from too many cameras. The more analog cameras installed, the more DVR’s needed. IP decentralised recording can decrease the amount of DVR’s required by up to 10 times!

Today IP network cameras meet the same requirements and specifications as analog counterparts and in many areas surpass analog camera performance. Forecasts show that the network camera market is growing at a much faster rate than its analog competitor. It is predicted that by 2008 digital surveillance will surpass analog.

Analog as technology is static or ‘dumb’. It lacks the flexibility and performance needed for today’s digital world. Network cameras move digitisation and compression out of and away from DVR systems. In this sense IP video is an ‘intelligent’ form of technology that can scale to handle thousands of cameras, with cost effective, industry standard servers for recording and storage. Many new ‘intelligent’ IP Cameras have a large range of advanced features built into the cameras which are simply not available through traditional offerings.

When converting to the new technology it is wise to look at some of the key differences between the technologies.

- Interlacing. Analog technology even at (4CIF) has a significant problem with interlacing, causing moving objects to blur. A network camera can progressively scan moving objects more clearly. There are no separate interlaced lines, so this method provides a much clearer image.

- Power. Powering an analog camera can be costly and difficult. Firstly coaxial cable must be installed to transport the video then power cabling fed to each camera. Network cameras can be run from the Power over Ethernet (PoE) standard, which means cameras can be run over the same cable that transmits data and power.

- Ups Integration. An additional advantage of using PoE enabled Cameras and LAN Switches that is often overlooked is the fact that protection against power loss can be implemented much more cost effectively and simply than for analog CCTV. Traditional analog CCTV cameras require power at each location, thus providing backup power for each camera can often be very expensive. However an IP camera system using PoE, power is injected centrally at the network switch thus one or two UPS’s supplying that switch automatically provide backup power to all the cameras. Often it may be the same UPS already in place for the PC and Servers

- Resolution. Analog cameras cannot provide resolution above television standards, which corresponds to 0.4 mega-pixels at 4CIF. Many analog systems run at a much lower resolution due to technical and cost restrictions, operating at 0.01 mega pixels. Network Video technology can provide a resolution up to 15 times the quality of analog video. The latest cameras now can process video up to 3Mbitp/s.

- Intelligence. Network video technology allows the cameras to have a much higher range of ‘built in’ features. For example cameras can be programmed to only record on movement, vastly reducing network load. Other features include sun and backlight compensation, dual lenses technology, internal digital storage, audio and SIP telephony.

IP Video is a proven technology that has many advantages over traditional analog CCTV systems. It is estimated that 25% of security users use IP, while 45% have plans to upgrade. IP technology is very easy to upgrade and expand. With new technology developing IP surveillance systems will become more ‘intelligent’ and give greater return on investment. The total cost of an IP based system including cameras, cables, and recording is considerably less expensive than analog.

Please feel free to call us to discuss your specific needs, we will tailor a solution for you.