Video surveillance has traditionally been a closed-circuit analog affair run by the physical security staff. But with the rise of IP-based digital systems, video surveillance has become another application on the corporate network managed by the IT department.
Motion-activated digital surveillance cameras, including those from Mobitex and Axis, are IP-based and capture better detail than analog cameras, with video footage typically stored in corporate servers and shared over IP networks. But digital cameras tend to be almost double the price of analog cameras, so organizations think twice about throwing their old cameras out. A transition step often involves converting analog to digital streams to transmit video surveillance traffic over corporate LAN and WAN links.
That's the approach that the state of Utah is taking in two separate agencies, the Utah Department of Alcoholic Beverages (UDABC) and the state's Department of Transportation.
The Department of Transportation owns 700 miles of fiber-optic cabling, and among other purposes, it's been used to stream traffic from 445 analog cameras from several manufacturers, including Pelco, back to a central data transportation monitoring center in Salt Lake City.
Richard Manser, the department's specialist for intelligent transportation systems, says the agency is halfway through a process of converting analog video streams to digital through hardware upgrades, decoders and changes to its Transcore management application to support IP-based monitoring.
"IP Ethernet is much more flexible," Manser says. "Analog requires dedicated fiber strands for each group of eight cameras. The cameras are streaming all the time and tying up bandwidth, typically 4.5 to 6Mbps per second per camera. With IP-based digital video, you can use on-demand and multicasting, which definitely is less bandwidth. Maintaining it is easier because we have people in IT experienced in network management."
UDABC, which controls liquor sales in the state, also decided on a similar analog-to-digital transition step for its 38 state-run retail liquor stores that are monitored for theft by Toshiba cameras.
"We can convert the analog Surveillix-brand cameras from Toshiba with their video-capture board now," says Kevin Perry, UDABC's tech support specialist supervisor. The state agency would prefer fully IP-based digital cameras because "digital's quality is better and analog cameras are not motion-sensitive." But due to considerations about expense, the decision was made more than a year ago to make a gradual transition.
If a store manager suspects a theft has occurred, a review of video footage stored locally in servers may result in a video extraction that can be remotely viewed by authorized state employees or law enforcement.
The decision to share video surveillance footage over the state's WAN prompted bandwidth questions.
"We first looked at streaming 100 percent of the data from the cameras across the network" to the UDABC's main data center in St. Lake City, Perry says. But with 15 frames-per-second video taking up about 2Mpbs of bandwidth, that idea was viewed as too bandwidth intensive. The state of Utah decided to set up storage-area networks locally in the liquor stores to warehouse a month or two of captured video.
As with other Windows XP-based computer systems, the Surveillix pan, tilt and zoom system has to undergo maintenance.
"We do patch management and run antivirus on it," Perry says.
Managers of video surveillance systems need to be sure they understand the federal and state laws that may apply concerning privacy, Perry points out. And there are laws specifically prohibiting recording conversations so surveillance systems typically are visual but not audio recorders.
Network-equipment giant Cisco is bullish on IP-based video surveillance, getting into the business earlier this year through its acquisition of SyPixx Networks, a maker of physical-monitoring systems that support both pure digital IP-based video cameras or analog-to-digital and digital-to-analog traffic.
"Ninety-eight percent of the installed video cameras are analog today," says Mark Farino, general manager of converged security in Cisco's Emerging Market Technologies Group. Farino says Cisco's strategy is to support the transition from analog to digital, while introducing innovations of its own in the coming year.