Ask The Expert
This month's expert delves into the new technologies being used today for protecting a perimeter
- By Mike Painter
- Jul 01, 2006
MOST security directors and facilities managers take the approach that it is never too early to stop a potential intruder. Fortunately for them, there are plenty of perimeter security options -- from low-tech fences to intelligent video software -- available to help keep the bad guys at arm's length.
The costs, benefits and drawbacks of lighting, fences and concrete barriers are well-known. Following is a look at some of the more sophisticated choices on the market.
ISSUE: What are some of the technologies being used for perimeter protection?
SOLUTION: The wave of the future in perimeter protection seems to be headed toward the use of video and related technologies. Intelligent video, or video analytics, is one of the latest technologies being used for perimeter protection. Highly complex algorithms are used to automatically analyze live video images to detect differences between events such as a moving person or a tree blowing in the wind. Users can create virtual tripwires on the video displays, and the intelligent video software will generate an alert when violations are detected. The technology can even create an alarm when suspicious objects are left in critical areas.
A major benefit of intelligent video is that it automates video monitoring, allowing security personnel to handle other areas of concern. However, the technology does have some limitations. For instance, the software depends upon light to detect images. Darkness or poor weather can limit its effectiveness. Infrared cameras can be used to spot intruders in those situations, but the cost of thermal imaging is still very high.
Intelligent video is getting close to being ready for general application, but for now, its costs limit it largely to homeland security and other government applications.
ISSUE: Are there any other technologies being used for perimeter protection? If so, what are they?
SOLUTION: Another choice for perimeter protection that is limited in its application involves the use of vibration detectors. Currently, the Border Patrol counts on this technology to protect hundreds of miles of uninhabited areas along the border with Mexico. However, vibration detectors require a quiet environment, making it ineffective for areas with regular vehicular traffic or movement of large numbers of people or animals.
For perimeters of up to 200 yards, microwave technology may be a good choice. Microwave systems use pole-mounted transmitters and receivers to set up a volumetric pattern. These systems can interface with video surveillance and access control systems, so that breeches can be displayed on monitors, and surveillance cameras are automatically pointed to provide live video of an intrusion area.
The cost of a microwave system is moderate -- especially compared to intelligent video -- and the technology generally produces relatively few false alarms. And since the transmitters and receivers are almost impossible to conceal, a microwave system may act as a deterrent to would-be intruders.
However, microwave systems are less accurate than some other technologies in pinpointing an intrusion site. Most systems are only accurate within 5 feet.
One more technology has been in use for more than 30 years, but is still considered a viable way to protect perimeters at airport, military and nuclear facilities. Leaky coaxial cable (LCX) works by outlining a facility's fenced perimeter with parallel LCXs buried just inches underground. One cable transmits an electrical signal, while the other acts as a receiver. The pair creates a continuous electromagnetic field that is generated above ground. Intruders passing over the cables disturb the field and create an alert.
Leaky coax, however, may not work well in areas that experience extremely cold winters. Frozen ground and several inches or feet of snow can significantly reduce the sensitivity of the buried cables.
In the end, the best advice to designing a perimeter protection system is to work with an experienced security system integrator to determine which solution will fit your budget, the environment and the scope of the project. The integrator plays a major role in making sure that the perimeter technology your organization selects will work seamlessly with your existing video surveillance and access control systems.
This month's question from a reader asks:
ISSUE: Just over two years ago, my company, a large tool manufacturer, made the switch from VCRs to DVRs. Now, I am starting to read about NVRs. As we begin to update our CCTV system, we are considering changing to IP-addressable cameras. If we do, are the NVRs really ready and a good choice from both performance and investment points of view?
SOLUTION: We recently responded to an RFP that addressed the replacement of an existing CCTV system. Their current system is made up of a DVR and traditional analog cameras. The RFP was written because the DVR, as well as some of the analog cameras, had begun to fail, and the camera coverage requirements had changed.
DVRs are built using industry standard hardware. The life expectancy of computer hardware is limited. The migration paths to upgrade a DVR is limited, and with all the responsibilities placed on the IT department to secure the network, it is becoming more and more difficult to attach DVRs to the network and take advantage of the network infrastructure to share video.
IP-based video solutions and NVRs have shed some light on this fast-paced technology.
1. NVRs allow the IT department to build, maintain and control the servers used to store the video and the software to run them.
2. Existing network infrastructure can be used to move and add cameras.
3. The IP video market is quickly becoming the standard for the future.
Overloading the network with streaming video is a concern. As network technology has advanced, so has the ability to handle streaming video on the network. IP-based cameras and IP converters are continually being deployed with the latest and best compression algorithms that deal directly with bandwidth and storage requirements.
The NVR solution is definitely the next generation in the video management evolution process. As more people learn and understand the benefits, we expect to see the deployment of NVRs increase.