However, different cameras perform best under different lighting conditions, and it is important to determine if there is not only a sufficient level of nighttime light, but also if the type of lighting is optimum for the cameras being considered. Additional or different luminaries may be required, or the budget may be better spent on higher-quality cameras capable of producing adequate video under existing conditions.
Space. At the other end of the system is either a video recording system or a monitoring station, or both, and space is needed to accommodate these. DVRs and NVRs take up little physical space and, being computer systems, may be best mounted in a vertical rack in a computer room or LAN/IDF closet. Monitoring usually requires multiple video screens that are traditionally housed in a console. Since the displays are now more often flat, thin, LCD screens, special tables with screen support columns-more commonly seen in IT help desks-are starting to replace the older multi-bay consoles.
What Staffing Issues Will Be Raised?
Discussion of monitoring equipment and its space requirements should be preceded by serious questions regarding real-time monitoring and recording schemes. Real-time monitoring is defined as a trained individual watching the camera scene as the original image is being displayed; any image that is recorded/archived can be viewed later but not while the action is occurring. The options available for monitoring and recording of video images are many, and they're not exclusive. For example, an image can be recorded only on "alarm" activity but monitored at all times. However, "No monitoring" and "No recording" indicates a dummy camera, which is not recommended under any circumstances. Indeed, if any camera is overt but not monitored, signage should be used to remove patrons' expectations of responsive security. The word "alarm" is in quotes because the activity may be automatically initiated by an off-normal sensor signal, such as a perimeter intrusion detector, or by digital processing of the video image itself, as described above.
Calculating the quantity of cameras, the time required to monitor them, and the time required to review recorded security incidents will provide an indication of staffing requirements. Of course, this is in addition to other security officer duties such as patrol and response. Typically, monitoring video scenes is very boring-imagine the worst TV show with almost no action and the sound turned off-and consideration should be given to frequent rotations at the monitoring desk.
We can only skim the surface of security video system design in a single article. The intent is to provide some direction and indicate areas of future research. In the last decade video systems have evolved from the connection of a few simple components to an integral piece of the information technology world. The IT professionals control the networks that may be needed for video signal transmission, and they control IP addresses required to connect to their media. Where CCTV system layouts required the designer to know the transmission limitations of coaxial cables, video system design needs someone who speaks the IT language of bandwidth, chokes, Category 5, and fiber.
The end user should understand the design process and the skill sets needed to develop the technology solutions, but, as in other areas of IT, the application software is the driver. The security practitioner needs to keep abreast of current, off-the-shelf capabilities, and of the exciting new capabilities that are being developed each day.
David G. Aggleton, CPP, is president and principal consultant at Aggleton & Associates, the New York City-based security consulting firm. Mr. Aggleton has been gaining experience in the security industry since 1978 and as a security systems consultant since 1985. He has taught the principals of the security technology design process at ASIS workshops, at ASIS, IFMA, and other industry conferences, and at John Jay College of Criminal Justice.
This article was published in the March 2005 issue of ST&D magazine.