Managing Infrastructure Impact
The issue of network impact when utilizing an existing LAN is of utmost importance. One way to entirely eliminate the impact of video on the campus’ existing network is to utilize a separate physical LAN for video surveillance. This network can then be connected to the building’s LAN through a switch. Another way to minimize impact is to create a virtual LAN within the network, which will allow you to regulate data traffic for better control and performance.
Another option is to use intelligent IP camera technology, placing it on the edge of the network. This will reduce bandwidth concerns as video is then stored in the camera where it can be downloaded during off-peak periods.
“The advantage of recording video on the edge is you only bring the changes [down the wire], or you can do that between certain hours,” says Roberto Testani, senior product manager, Honeywell Video Systems. “You have control of what you want, or you can record at the edge and then periodically pull all motion generated alarms. You also can pull that data down according to schedule.”
Bandwidth is especially important when working at the enterprise level where several video networks from multiple facilities are linked together. This is because the available bandwidth among facilities is usually less than what is available to IT within the LAN in each building or campus.
“You have to control the data coming down the wire,” says Testani. “For example, if your bandwidth is provided by a T1 line, in the majority of installations the video info is sent directly from the camera to the recording device. But it can be expensive to have a dedicated IP line for video surveillance.”
This is where the ability to download changes that take place in video images at certain times of the day, or under certain conditions, is important.
The other issue is the additional impact on network resources when IP cameras are selected for outdoor applications.
“Lighting is important. You can have a million-dollar system and if it’s not built for low light, it’s worthless when the lights go out. IR illumination is becoming a necessity,” Testani claims.
He points out bandwidth use at night greatly increases. “It doubles or triples your bandwidth and that is why illuminators are so important for IP cameras,” he adds. “When it goes into low-light mode, the bandwidth will go off the chart.”
IP cameras offer many more benefits and features than analog cameras. But having a firm understanding of the technology as well as networking details is essential to a successful deployment. Campuses must be prepared and ready for the day when IP overtakes analog video, and for many that day is already here.
Al Colombo is a long-time trade journalist and copywriter in the electronic security industry. He has 15 years experience as a field technician and 28 years in technical writing.
