By Mark Jarman
April, 2008
In any type of commercial setting it is essential to have a functional and reliable intrusion system to ensure the security of employees, customers, business assets and overall investments. The integration of such systems is facing greater challenges as security budgets shrink and the timeframe demands for installations tighten. As a result, innovations to the traditional hardwired approaches are being tackled wirelessly, and wireless intrusion systems are being recognized by many commercial enterprises as a faster-to-install, less expensive, easier-to-maintain, flexible intrusion solution.
Wireless intrusion detection devices send an alarm signal when there is an inappropriate entry or unusual activity in an area. Devices are typically independently placed at a variety of entry points including any sensitive location that requires additional monitoring, alleviating wires and conduit. The system is made up of transmitters to detect an open window or door, passive infrared motion sensors to detect uninvited guests, or glass-break sensors that indicate a broken window, door or display case.
Simply being wireless enables far less labor and, therefore, less cost - there aren't any wires to run; just place the sensor and turn it on. It also allows for easy changes to the configuration at any time. The real innovation is in how these wireless devices can be effectively used in large commercial buildings as wireless mesh networking.
Operating an intrusion system through a mesh network is becoming increasingly popular. In the current marketplace there are a number of definitions and details about the infrastructure; however, much of today's talk is based around two ideas:
- Mesh networking is a way to route data, and instructions between nodes or endpoints
- Wireless mesh is a wireless cooperative communication infrastructure among a massive number of individual wireless transceivers
"There's some confusion regarding mesh networks," says Chris Larcinese, vice president of sales and marketing at Inovonics. "Coupled with the abundance of wireless intrusion products and set-ups, it makes the selection and installation process seem like a daunting task. Simply put, a mesh network is an advanced way to transfer information that is reliable and scalable."
When it comes to intrusion detection, the definition itself isn't as important as the benefits mesh network provides: scalability, reliability and flexibility.
Expanding Scalable Options
In simplest terms, a wireless mesh network is designed with the growth of a business, a campus or a facility in mind. As additional applications - such as submetering, fire extinguisher monitoring and environmental sensors - converge in the same building, the mesh network can be leveraged to support these additional demands. For that to be a reality in wireless systems, greater intelligence has been built directly into the latest generation of infrastructure to manage those endpoints.
In addition to scaling the number of applications supported on a mesh network, scalability can also refer to the ability of extending the native range and the number of end devices beyond its initial design, allowing coverage of a large or growing facility. Advanced wireless technologies use an intelligent repeater network to create wireless coverage throughout the entire building.
As the desired areas of coverage for security and intrusion detection devices expand, the network can expand with it. Simply integrate additional repeaters into the infrastructure and it will automatically reconfigure itself to optimally include these new components. For example, on a municipal campus, when the number of buildings expands, the number of repeaters and endpoints can be adjusted requiring minimal labor hours, thus saving thousands of dollars. If offices or buildings are added to the campus or a department is physically moved, the network easily scales to accommodate the new endpoints. "Applications and equipment can be integrated into the wireless mesh network by simply mounting devices where they are needed," says Doug Yarger, owner of Southcross, a security integrator in Houston. "This process doesn't disrupt employees, their workflow or even the architecture itself."
Reliable Message Relay
Wireless networks are as reliable - if not more so - than their wired counterparts. Mesh networks are designed to get messages from endpoint to endpoint as efficiently as possible. Since these devices can be installed at remote locations, the ability to verify the endpoint is present and working properly is critical.
Verifying endpoints is managed by system supervision. The endpoint and repeaters send "state of health" check-in messages to notify the receiver of their presence and condition. When used in security and other life-safety systems, the time between check-in messages is critical and should ideally be configured to occur several times in an hour.
If the wireless environment should change due to a manual reconfiguration/relocation of devices or device failure, the system will "heal" itself by finding an alternate path of communication from any specific endpoint to target destination.
"Don't overlook the self-healing benefits of wireless mesh. That's a real advantage over wired security systems. If a wire corrodes, is damaged or otherwise rendered inoperable, that's it. There's no communication to that point and it has to be repaired," says Yarger. "But if a network can 'heal,' it reroutes the messages through a path that works."
Another important component in a mesh network is the ability to intelligently route those messages depending on their priority through the system. For example, a life-safety or intrusion alarm message must always take priority over a meter-read or a temperature report. The mesh network infrastructure messages must carry a high level of intelligence and the infrastructure itself must be smart enough to interpret those messages correctly. If an intrusion alarm attempts to send a message from a broken window in a manufacturing center but the path to the typical receiver is blocked, this innovation pushes the message through an alternative path, avoiding other notifications such as an environmental alert because of the intrusion alarm's priority level.
Additionally, mesh networks based on frequency-hopping spread-spectrum radio technology are inherently more reliable when compared to single-channel technologies. Frequency-hopping radio regulations allow for more frequent system supervision and greater transmission power, which results in a larger coverage area with an overall, more robust system performance.
Flexibility for the Future
The best wireless systems are designed to provide maximum flexibility for the user. Once a wireless mesh network infrastructure is installed at a site, more applications can be added to the intrusion system resulting in more cost-effective deployments. Being able to amortize the cost of the mesh infrastructure across multiple applications presents the end user with a much better way to manage the operating expenses of the facility.
Integrating security pendant or panic button devices wirelessly gives key employees the ability to trigger an alarm from anywhere in the building without the encumbrance of wiring. In addition, pendants can be used as safety buttons for workers in case of an accident. This added measure of security works alongside of the intrusion system and enhances the overall value and dependability of the wireless mesh network.
One of the major benefits wireless mesh networks offer is ease of installation. By definition, wireless doesn't have wires to run through or between buildings. Wireless deployments also greatly reduce the impact on the facility as the new endpoints are being installed. Wireless installations also allow for easy and inexpensive reconfiguration of the endpoints if the physical layout of the environment changes.
For example, in a distribution center with a number of overhead doors, high ceilings, large open areas, multiple entry points and millions of dollars of inventory, an intrusion system must have numerous monitoring and detection points. Hardwiring a distribution center is extremely costly and would require pipe and conduit, hangers, wire, installation labor costs, and the equipment to lift the installers into position.
Installing a mesh network to monitor the access gates, the roadways to and from the building, and the building itself, saves thousands of dollars in equipment and supplies, and hundreds of unnecessary labor hours. If the site or floor plans require an adjustment, this system is much more flexible than a conventionally wired system.
Most locations have an existing security system in place, but successful enterprises are usually performing a number of upgrades somewhere in their facilities. "We see a lot of older buildings with a wired system that we augment with wireless as the client needs evolve over time," says Yarger. "It's a simple matter to add wireless mesh and its endpoints to an existing system and panel."
The ideal mesh network solution for life-safety or security systems will allow this advanced technology to work seamlessly with the control panel of preference, not just the ones offered by the maker of the mesh devices.
Time-Tested for Success While it's true wireless mesh networks are becoming more and more commonplace, they've also been around a lot longer than most people realize. There are thousands of security installations around the globe utilizing wireless infrastructures to help protect buildings and the lives within.
Many high-security government buildings, sprawling campuses, historical sites and high-profile commercial settings utilize wireless mesh networks to secure themselves from intrusion. These commercial wireless mesh networks - through scalability, reliability and flexibility - are providing immense benefits to the installers, owners and employees of those facilities.
Mark Jarman is the president of Inovonics, a provider of commercial wireless solutions. He can be reached via E-mail at mark.jarman@inovonics.com.