By Richard Koharik
The current popularity of horizontal wiring and expanded use of Internet protocol in buildings are driving a demand for products that can capitalize on these technologies. Not surprisingly, this demand has extended into the security realm, with building developers asking for the integration of video systems into their IP networks that may be used for surveillance, loss prevention, training, and management control.
The migration to IP-based surveillance solutions is making the costs of installation and ownership for fsuch systems increasingly affordable. In fact, many security integrators report cost reductions of as much as 20 percent when installing an IP solution. And the savings escalate over time, as systems require expansion. With no need for dedicated wiring, IP systems can start small and have additional cameras and storage space added as needed, at any time, by making use of simple network connections.
Components of an IP Video System
The components of an IP video system include both "video source" devices, such as cameras, lenses, encoders, transmission paths, and power sources, as well as "receiving/management" elements, including PCs, viewing monitors, software, and recording media.
Cameras are typically divided into the categories of "box" and "dome" cameras. "Cylinder" cameras are box cameras integrated into their own cylindrical enclosures for a softer profile and protection from the elements.
Technological innovations and new features appear first in box cameras. The major benefits of box cameras are a wide selection of available lenses; easy-to-reach controls and connections that make installation less costly; and easily identifiable camera shapes that act as a deterrent.
Dome cameras, by contrast, are designed to be discrete. There are two subgroups of dome cameras: fixed and moveable (known as pan-tilt-zoom or PTZ). Moveable domes offer the ability to cover large areas with one camera. Most security specialists will agree that moveable domes are best used either as an attended device for surveillance or to provide an automated response to alarm conditions, such as a door opening. Moving cameras should not be used to cover a wide, unattended area, as events may occur where the camera is not looking. For the most thorough coverage, security designers suggest installing low-cost fixed domes that cover everything and using moveable domes for special conditions and active surveillance. Both dome types are available in vandal-resistant and tamper-resistant models, along with versions that can be mounted on walls and flush in ceilings. When used in combination, it's difficult for observers to tell which are which - especially when the domes are smoked to conceal the camera inside.
Special-purpose cameras are available in box, dome, and cylinder form for conditions such as hazardous areas, low-light conditions, and environmental extremes. However, keep in mind that as any camera moves beyond offering the basics, the system designer must examine its feature set and quality more closely. Figure 1 shows common camera types.
Lenses are available in two types: fixed and varifocal. Fixed, or "prime," lenses are less expensive and deliver the best quality pictures, but are only able to focus at a single distance. Varifocal lenses can focus on a range of distances (within limits). When varifocal lenses are used within movable cameras, the lens can focus on different distances as it pans from scene to scene.
Lens size determines the size of a target on a viewing screen, or the degree to which it appears magnified. Therefore, it is important to understand how an end-user plans to use a given camera when specifying the lens that will be used. Different size lenses are used for monitoring, detection, recognition, and identification (see Figure 2). For example, a lens intended for monitoring an entire parking lot area will probably not provide the ability to read individual license plates.
After camera and lens selection, powering the camera is the next step. In a perfect IP environment, Power over Ethernet (PoE) is the best choice but not always possible.
The current IEEE standard for PoE is 17 watts. For powering basic, indoor IP video cameras, this is sufficient. However, there are many situations in which cameras require more than 17 watts to operate, such as outdoor cameras with heaters and cooling fans, and moveable cameras with motors.
Until a new PoE standard (PoE Plus, 30 watts) is adopted by switch manufacturers, most mainstream environmental and moveable cameras will require an external power source. In these cases, conventional CCTV power can be used.
For IP cameras that do not require more than 17 watts to operate but have not been designed with PoE, it is still possible to bypass the need for conventional power by using a device called a power injector. This will allow a non-PoE camera to receive its power via category wire.Encoders
Using IP cameras exclusively is not always practical. In situations where analog cameras need to be integrated into an IP system, encoders convert the analog video into a digital stream. For example, certain desired camera locations - such as elevator cabs - may only have coax cable or twisted pair available for signal transmission. An analog camera mounted in the elevator could transmit through prewire travel cable to the outside of the elevator shaft, at which point an encoder would convert the signal to digital and serve as a gateway to the network. IP video encoders are also well suited for integrating existing cameras with a new IP system and for use with special cameras that are only available as analog devices.
Current network technology provides more than enough bandwidth to support a typical IP-based video viewing and recording system. Most new networks offer 1 Gbps (gigabits per second) total bandwidth with 750 Mbps operating capacity. A typical video system of 10 cameras might use 15 Mbps,* consuming only a fraction of the total. It is common for the video system to ride along with normal IT work flow.
In those situations when there is a high demand for bandwidth, such as when a network is performing daily backup tasks, a "Quality of Service" or QOS feature allows a network to determine which tasks receive priority. If it is imperative that streaming of surveillance video not be interrupted, then the network can allocate the required bandwidth to support the video system at all times, with other network tasks only using the remaining balance.
Video management software (VMS) is the heart of an IP video system, allowing the various components to "speak" with each other and enabling the playback of recorded video. Many software providers build all features into the software but do not make all features accessible at the basic cost. The higher-end features, only required by a small subset of users, can be "unlocked" for an additional fee.
At the basic level, the ability to select cameras for viewing live and recorded video should always be included. The interface for viewing should be easy to understand and the management program easy to set up.
To optimize a system's performance, many VMS providers package the management software and the computer it resides on. However, because most business owners standardize on one brand of computer to simplify IT, VMS manufacturers also offer software available separately.
Viewing apparatus for an IP video system can be as simple as a PC monitor or as elaborate as a video wall. Other choices can be handheld devices for on-site security personnel and purpose-limited software on laptop computers used by non-security employees. Public view monitors placed where they can be easily seen by visitors and contractors add an important deterrent factor.
Through the magic of IP, off-site video system monitoring is easy to accomplish. Network attack risks do need to be addressed, but video system access poses no more risk than any other outside access.
How Everything Fits Together
Using simple drawings to reinforce an IP video proposal will promote understanding of the concepts. Block diagrams in your presentation will allow the quick addition of new features brought out in your conversations about the project. Figure 3 demonstrates a complete basic system. As you can see, additions can be added as your discussions with clients progress. Your end product may be as simple as a one-page specification or concept drawings that are turned over to a security design professional for further refinement.
Video system design should be guided by an interview with the owner, during which the owner should define his or her expectations. Some questions to ask include: Will the building be open to the public? Will a reception person control access to the building? Do employees enter and exit only during normal business hours? Would you like to view your building activity while you travel? Do you employ contractors and/or casual labor to perform work in your building with no supervision?
The type of business the owner engages in may also point to the need for IP video. The regional office of a multilocation business, such as a fast food franchise, requires not only a surveillance system for the building itself but also remote access to the video from each store location. An IP solution allows for integration of both on-site and remote video into a single system.
Obviously, the layout of both the interior and exterior spaces of the building will also drive the video system design. Enclosed exterior areas such as a parking garage or storage buildings are good candidates for video observation. Control for shipping and receiving areas and rear employee entrances are often areas of concern that can be addressed with correctly placed cameras.Component Selection
During the interview stage of the project, the purpose for each camera should be addressed. "I want a parking lot camera" is generally not enough information from the client. "I want a parking lot camera that allows employees to view the parking lot prior to going to their cars after dark" is information that can guide the selection of camera placement, camera type, and lens type.
If the purpose of a camera is to act as a deterrent to bad behavior, making the camera visible is the best. Looking at the performance of a camera is just half the task; size, appearance, and mounting method all play a part in the design.
Light ratings of 2 lux, in a color that is close to natural daylight, will assure the best pictures from a color camera. However, today's cameras have low-light capabilities well below 0.008 lux. Often, that performance is achieved by amplifying the light - an effective solution for viewing, but one that has side effects. In the process of amplifying the light, picture noise is inadvertently added to the image. This is translated to additional data that will require more recording space (requiring a larger hard drive).
For special applications that require cameras to operate in low- or no-light situations, cameras can be equipped with IR light sources. Many manufacturers also offer wide dynamic range (WDR) versions of their cameras. These cameras are designed to provide a clear image of an entire area when parts of the view may be bathed in bright light and other parts are in shadow. Without a WDR camera, such an image might appear washed out and without adequate contrast.
Going "wireless" presents advantages both in terms of cost and ease of installation. Cameras may be installed just about anywhere, including far away from buildings, without the hassles and expense of installing underground wiring.
Adding a secure wireless access point may also provide the ability to view indoor cameras from outside the building. The Columbine incident may not have had as tragic an outcome had responding police been able to view the existing inside cameras from a remote command center. Choosing the right wireless platform is best left to an IT professional trained in this area.
Technical advances in what IP video systems can offer are leading to a new recognition by many companies that properly designed video viewing and recording systems can increase efficiency, reduce labor costs, and enhance marketing efforts.
IP-based video systems can start saving money for a building owner as early as the construction phase. IP cameras installed at a construction site can allow design professionals and engineers to supervise and document projects remotely via webcams, ensuring that on-site work is being done correctly and according to schedule.
Retail business is using remote viewing to assure that stores are open, staffed, and meeting standards of cleanliness. Routine tasks, such as supervising contract labor and inspecting remote buildings and grounds, can be done by remote video.
Intelligent video, or "video analytics," is now providing retailers with added value from their surveillance systems. Although originally designed and intended for high-level security applications, video analytics is now being used by major retailers to gather marketing information and alert managers on such issues as long checkout lines. This video technology can be used to detect motion, lack of motion, direction, and crowd density. The solutions that video analytics can provide seem endless.
Video surveillance systems have evolved a great deal from the traditional, hard-wired CCTV systems of merely a decade ago. While lowering the total cost of ownership, IP technology has simultaneously expanded the possibilities of what these systems can do in countless ways. Remote viewing, flexible system design, integration of analog and digital components, unlimited potential for system expansion, and value-added features such as video analytics have made the exclusion of a video surveillance system in any future building plans an impractical proposition.
With a little bit of education and the right tools, technology specialists at A&E firms should find it easy to specify IP video systems into their plans. The result will be more initial revenue for the design firm, ultimate savings for the end-user, and, most importantly, a more thorough and functional solution that will meet the client's needs for years to come.
Richard Koharik (firstname.lastname@example.org), manager of A&E Services at Vicon, has been involved in electronic security for more than 25 years. His experience includes employment with a major international security provider as a project manager, trainer, national account manager, and general manager. For the past 10 years, he has concentrated on video surveillance technology within the security industry.
*Based on 10 cameras recording and viewing at five frames per second each