Wireless Technology: What you need to know to be successful
By Matt Nelson, CEO and President of AvaLAN Wireless Systems, Inc.
Wireless technology enables quick and easy installation of security cameras and access control systems. Wireless can eliminate the need to pull data cables in a security network which can save time and cost. In addition to cost savings in the initial installation and deployment of security network, the creation of a wireless network infrastructure can enable a platform for future sales of additional equipment and services. Embracing wireless data networking technologies also enables integrators, dealers and installers of security systems to offer more to their customers in terms of additional remote monitoring services and on-going network system management and support. Having over 25 years of wireless industry experience, I hope to impart some of the tips and tricks that I have learned for the successful deployment of a wireless security network. To begin, it is helpful to know what wireless technology is being used and deployed in today’s marketplace.
Wireless technology continues to improve each and every year. Two main characteristics drive most of the wireless technology changes we have seen in the past and what we can expect to see more of in the future. First, data rate continues to improve each year. Similar to other data networking technologies, data rate plays a major factor in the cost and configuration of any wireless data networking system. Today’s data rates seem to be climbing from 10s of megabytes, to hundreds of megabytes, to even gigabyte speeds. Higher data rate wireless networks are being deployed today in direct response to higher resolution and higher frame rate cameras that are now available. In addition to higher and higher data rates being available, encryption technology has also been evolving. Data encryption is important on wired as well as wireless networks. Wireless encryption technology is important to protect and secure video and data across the network. NIST (National Institute of Standards and Testing) certified 256-Bit AES (Advanced Encryption Standard) encryption technology is some of the best technology deployed today and will serve a basis for good quality encryption for most installations. Sometimes, simple password access and encryption key exchange to a wireless system is not sufficient. In addition to encryption technology, proprietary over the air protocols and non-standard wireless frequencies can be explored. Knowledge is money when it comes to understanding the advantages and dis-advantages of different encryption technologies being deployed on your wireless security network infrastructure.
Different security applications require different types of wireless technology. IP video surveillance systems require large data rates. Wireless access control systems require only small amounts of data rate. As the number of IP cameras that you have on your network increases so must the date rate capacity of your network. Access control systems that are opening and closing doors and gates use very small amounts of data but, security of the data is paramount. If biometric data is being sent then the encryption and data integrity validation is critical and may require additional network specialization. In general, wireless security networks need to be reliable and function to meet the needs of your customer. Wireless technology that has a proven track record in the security industry is typically your best place to start when choosing a vendor or particular product. Those of us that have been in the wireless industry for a period of time have learned a few tricks for what works and what does not.
Due to the very nature of wireless being unseen, the technology itself can seem mysterious. The following tips and tricks can help you in your deployments of a wireless security network.
- Understanding what is in the air can be half your battle - Using everything from your laptop to a sophisticated spectrum analyzer there are a number of tools that can be used to see and detect what is in your wireless environment. Many industrial wireless devices include some level of wireless environment analysis tools built into the device. Knowing how many WiFi access points and devices are in the same general area of deployment can be critical to understand where and how to deploy your wireless security system. Other radio frequency (RF) emitting devices can impact your signal quality and reliability. Remember that every laptop, phone, and headset will be fighting for use of the RF spectrum in any given area. Alternative frequencies should always be considered. In the USA, 900Mhz and 5.8Ghz can be used as alternatives to the more commonly used 2.4Ghz frequency band. Additionally, municipalities can register to use the 4.9Ghz frequency as another alternative to using the more common 2.4Ghz Wifi. Mitigating interference using frequency, channelization, antenna location and directional antennas can all help to insure a robust and reliably performing wireless security network.
- Line of site (LOS) and non-line of site (NLOS) wireless - One aspect of wireless technology that many integrators seem to ignore is the issue of how wireless performs in different environments. Using your common every day experience with Wifi and GPS wireless technologies you can gain a better understanding of how wireless signals propagate. Standard rule of thumb for any integrator or dealer when configuring a system is that wireless prefers open air line of sight connections to every other alternative. Now, that being said, wireless RF signals do go through walls and objects. Generally, if the object is wood the signals will pass through better than metal or water. Different wireless frequencies have different propagation characteristics. Frequencies below 1Ghz can pass through and around objects better than frequencies higher than 1 Ghz. Additionally, narrow bandwidth signals and higher RF power signals pass through objects better than wider bandwidth, lower power signals. In general though, most RF (radio frequency) guys like line of site and open air connections.
- To mesh or not to mesh that is the question - Wireless “Mesh” networks are all the rage these days, gaining a reputation among customers of various industries where fixed wireless Ethernet installations are required. The allure is great, we get it. The idea that a professional design and installation company can buy multiple radios with mesh networking firmware and scatter them wherever they need an Ethernet device and then connect them back through the mesh to the head end network location. It sounds as simple as hitting the easy button but it has proven to be both tall on excitement and small on performance. Whether it’s a PLC or IP camera, the “magical mesh theory” that promises to make challenging installations simple and reliable has bitten many a professional installer in the backside. Mesh is a great theoretical technology yet more often than not it comes up short in the real world. Simply put Point-to-Point (PTP) and Point-to-Multipoint (PTMP) wireless Ethernet installations are still more predictable, more reliable, and more cost effective. The benefits of the PTP and PTMP far outweigh the risks of Mesh. It will benefit you to take the time in the design phase and architect a “predictable path wireless system” of overlapping PTMP (Star) topologies. We all have lived long enough to know there is no true “easy button” in life. The great allure that wireless Mesh networking will magically solve all fixed wireless installations challenges has proven to once again remind us why professional design and installation will be required for years to come. Perhaps it will be solved one day. Until then stay PTP or PTMP friends.
- Wireless wires - Many dealers and installers start down the wirelesspath and forget about electrical power. Wireless systems can carry your video and data wirelessly but the cameras and wireless networking devices still require power. Wireless power today only comes in the form of solar, wind and batteries. Make sure you wireless networking configuration has a power plan. There are some great wireless devices that now support power over Ethernet ( IEEE 802.3af-2003 and IEEE 802.3at-2009 ). The IEEE 802.3at standard supports up to 25 Watts of power which is adequate to support most 802.3at standard POE cameras. Using POE can help to minimize power cabling and make for a cleaner installation. One other tip is to be sure to use outdoor cat5 if your installation is outdoors because indoor networking cables do not last in the outdoor environment.
At the end of the day, wireless networking technology has become common place in security systems today. Using tools to survey your customer’s wireless environment can significantly reduce issues in any deployment. Fully understanding your camera resolutions and frame rates required will dictate the amount of data rate you will require for each networked camera. Picking the right frequency and the right topology for you wireless network is also a key to insuring all devices on the wireless network will work with adequate performance. Knowledge is power. Just like your laptop and your cell phone, wireless networking technologies continue to improve and change each year. The more you learn and understand the better you will be able to serve your customers. Wireless technology can save you and your customers cost and greatly ease the burden and complexity of many complex security system installations.