By Tom Condon, RPA, FMA
Published in the March 2008 issue of Today’s Facility Manager
The management of facility systems is increasingly moving toward computer based technology and becoming IP (Internet Protocol) enabled. While this scenario offers amazing functionality, I have been hearing from many facility managers (fms) lately that these new technologies are often failing to live up to their expectations.
As I have counseled a good number of fms on this topic, I have seen a clear trend emerge. The number one item causing problems with computer based facility systems is the IP network upon which they operate. This often forgotten component is actually the key to advanced facility technologies like Voice over Internet Protocol (VoIP), Wireless Local Area Networks (WLANs), and digital video surveillance. Fms need to understand network systems and the impact that they will have on facility technologies.
First, a quick review of networking basics is prudent here. In order for computers to communicate with each other or with devices such as IP cameras, VoIP phones, or wireless access points (WAPs), they are connected by cables through which tiny electrical impulses race back and forth at almost the speed of light. These signals are, at their most absolutely basic level, either on or off; so, modern networking is essentially an extremely complex Morse code operating at near light speeds. The electrical signals are grouped into packets that carry a small amount of information; multiple packets are used to send larger files. IP is basically a set of rules that governs the way the signals are organized and how the equipment handles those signals.
The CAT5 or CAT6 cable that comes out of your computer goes to a wall jack, where more cable inside the wall leads to a port on a network switch. And that’s where the magic happens. The switch knows what is connected to it and sends information back and forth as the computers request connections. The switch is intelligent and can identify a computer on the network by reading its individual IP address (this is why you can move a computer from one office to another and the network still knows where you are).
So why do some facility technologies have problems because of these networks? Let’s look at two common scenarios.
The first example concerns an fm who installed a VoIP system and was having trouble with dropped calls and delays. After she called me, I had a Cisco Certified Network Associate (CCNA) technician perform a capacity test on the network and found that it was overloaded from the VoIP system. Telephone conversations require far more network resources than more mundane applications like e-mail or most Web surfing. Also, phone calls are real time and cannot tolerate the kind of delays that don’t matter for e-mail. If an e-mail arrives a few seconds late, you probably wouldn’t notice, but if your phone conversation has a two second delay, it is infuriating.
In this case, we had the network technician do a survey of the network equipment, and it appeared that the switches were rated to have a capacity to handle the load, but they were not doing so. What we finally found was that the switches’ internal programming had never been modified from the factory generic scripts. Switches have an embedded script that tells them how to route network traffic, and this has a huge effect on the network capacity.
The technician re-programmed the switches to take advantage of some advanced features to help balance the load. He created separate Virtual Local Area Networks (VLANs) that divide traffic into different “lanes” inside the network; although they run on the same wires, each lane acts as a separate network. The technician created a VLAN for the VoIP system and assigned it the highest priority over the other VLANs, so that less time-sensitive traffic (such as e-mail) would wait if VoIP needed the bandwidth.
Another scenario where the network affected the performance of a facility system involved an fm who had installed 45 IP cameras throughout his facility. He had first done a pilot implementation with only three cameras, and it worked great. The picture was clear, the Web-based interface allowed him to see the cameras from his computer desktop or from any Internet-connected PC, and the security director loved the system. But when more cameras were installed the video became choppy and then unresponsive. Facility occupants also began complaining about slow Internet and e-mail.
The system vendor said it was not the fault of the product and suggested the facility network might not be robust enough for video. I had a CCNA technician perform a capacity test on the network and found it was overloaded from the video cameras. Like VoIP, video requires far more network resources than more mundane applications. One frame of video can be larger than hundreds of e-mails, and a video camera transmits up to 15 frames per second!
The prognosis here was not as simple as with the VoIP installation. There were several major problems in this network. First, the switches were completely obsolete and not capable of handling even half of the video load. The switches were replaced with new models, but when the system was tested, it was still slow.
The CCNA technician dug a little deeper and found a problem that many overlook: the network cable terminations were poor quality and were slowing transmissions. The contractor who had installed the cabling had done a poor job, leaving many of the terminations loosely connected. Just as in the VoIP example, the reduced network capacity was not noticed when the only network traffic was e-mail or Web surfing, but the use of video overwhelmed these shoddy connections. The cables were re-terminated, and the network’s capacity was restored. The video then streamed smoothly, even with all 45 cameras being viewed simultaneously.
There are a few important things to know when installing a facility system that will depend on a network:
Look before you leap: When considering implementing any new technology that uses your LAN, have an assessment done to determine the impact on your network.
Test, test, test: Before implementing any large scale system on your LAN, test for capacity without the new equipment to establish a benchmark. Then test again during implementation at various points to assess how it is affecting the system.
Any time you have network cabling installed or altered, insist that the vendor give a guarantee on throughput. Also, have them test their cables and connections for signal quality and report the test results for every port.
Get the right expertise: Networks are complex, and they require properly trained specialists. When doing network assessments and installations, get certified network technicians.
Check cables: Sometimes, network problems can be as simple as a loose or poorly terminated connection. Also, check to make sure CAT cables are not running next to fluorescent light fixtures; the high-frequency magnetic fields from the ballasts can interfere with IP transmissions.
Don’t give up hope; get creative: Some fms get discouraged because they cannot afford to upgrade their networks and cameras for IP-based video. Replacing an entire network can be very costly, but it is not always necessary. Consider hybrid video systems that use existing cameras and coaxial cable, but then digitize those signals to gain some of the features of full IP-based systems.
Get a realistic picture of the costs: When doing an IP-based facility technology, be sure to factor in cost of network upgrades. The fm who installed the video IP cameras ended up spending almost as much on the network as on the camera system.
With a few precautions and a basic understanding of networks, fms can cruise the information superhighway without a network crash.
Condon, a Facility Technologist and former facility manager, is a contributing author for BOMI Institute’s revised Technologies in Facility Management textbook. He works for System Development Integration, a Chicago, IL-based firm committed to improving the performance, quality, and reliability of client business through technology.