Recording, management, and storage. Because video servers use standard PCs for video recording and management, they are easy to integrate with existing IT systems and can be managed as part of that infrastructure. Video servers allow video to be stored with standard storage solutions, including network attached storage (NAS), storage area networks (SAN) and Redundant Arrays of Independent Disks (RAID). These storage systems are easily expandable, reliable, cost effective, and repairable or replaceable in case of failure. By contrast, DVR systems require proprietary hardware, which is more costly and difficult to replace or upgrade. CamCentral and the Alaska DOT also took advantage of the video servers' ability to handle firewalls, passwords and other network security technologyâ€”something that can rarely be done with DVRs.
Scalability. Both video servers and DVRs leverage existing investments in analog cameras, but only video servers make total use of network infrastructure. This is particularly important when expanding the network video system. An IP surveillance system is expandable in one-camera increments. DVR systems, on the other hand, expand in larger increments. Once the capacity of a DVR is maximized, a new DVR box with 16 or more channels must be added to the system, even if only a handful of cameras need to be accommodated.
Remote recording and monitoring. Video servers allow users to access and record video at remote locations, provided they have the appropriate authorization and login information. Off-site recording can be beneficial in retail environments where it guarantees that video is protected during a theft on the premises. Off-site viewing allows security personnel to keep an eye on their establishment without being on the premises.
Decentralization. Video servers decentralize digitization and compression functions, so information is handled at the source instead of in a centralized place. This opens the door for up-and-coming applications like intelligent video, which can be used in identifying abandoned luggage at an airport or reading a license plate number in a parking garage.
In the case of the Alaska DOT, using video servers allowed CamCentral to create specialized motion-detection software that was optimized for the marine environment. A centralized processing system, like a DVR, cannot handle such applications because computing power is a scarce resource that video and analysis are forced to share. Even networked DVRsâ€”which incorporate an Ethernet port for network connectivityâ€”do not provide the same functionality as a video server system.
Video servers can provide cost savings and more functionality than analog or DVR systems. They create a truly digital surveillance system and allow users to capitalize on almost all the benefits of network video while incorporating network cameras as expansion and upgrades are required.
About the author: As the general manager for Axis Communications, Fredrik Nilsson oversees the company's operations in North America . In this role, he manages all aspects of the business, including sales, marketing, business expansion and finance. He can be reached via email at Fredrik.Nilsson@axis.com.