Government agencies have experienced a dramatic demand for surveillance technology development to protect people as well as private and public assets. Recent security challenges — from boarding airplanes to protecting embassies — highlight the growing need for increasing security, especially surveillance.
One of the most challenging dilemmas that homeland security managers face is when and how to take the leap from an analog to an IP/digital video system. They want to jump to IP surveillance, but in a cost-managed way that extends the life of existing equipment. For most sites, this migration will take place gradually and, during the process, analog and IP solutions will have to coexist — in some cases, for many years to come.
Five major system areas need to be considered:
- Transmission and cabling, including power supplies;
- Storage and retrieval;
- Command and control; and
Cameras – Throw Out the Analog or Keep Them
A key consideration for homeland security executives is whether or not existing analog cameras or new IP ones will provide the image quality needed to achieve the functional requirements of the system. Different applications have different requirements — for example, some users require the ability to see and track suspects in changing lighting conditions, while others simply need to see that a corridor is clear. In many migration plans, specific locations of greater vulnerability or image detail requirements are ideal places for IP-based cameras, including megapixel and high definition models. One needs to ask if higher resolution cameras can help at each location.
As part of a co-existence plan, analog-to-digital encoders at the camera end can transform images from an analog camera for digital transmission and storage. The analog control room equipment gets scrapped, but the new IP control room equipment controls the already-installed analog cameras.
Another approach holds down the budget at the beginning — the existing analog equipment, including cameras, control room, video wall and cabling remains untouched. VMS software, integrated with the present keyboard, sits on top of the system to manage the new IP equipment and the already-installed analog system.
Coaxial, shielded twisted pair and unshielded twisted pair cable, fiber optics and — to a lesser degree — a variety of wireless approaches, carry most homeland security video. The difference and business advantage of the various transmission schemes are in cost of installation and cost of maintenance. A question to ask is whether or not the new IP cameras will eliminate long-distance analog cabling.
One strategy to handle both analog and digital networks is to transmit all the signals over a single fiber optic cable that is secure and immune to electrical or environmental interference. Installation is dramatically simplified by eliminating the need for multiple fibers, transmitters and receivers.
Not to be forgotten are power supplies. Following a co-existence plan, power supplies that are multi-tap, addressable and programmable have advantages.
Other considerations include the increased bandwidth impact on the enterprise’s network. This is a tricky assignment, and IT can help. Will newer types of compression, decompression or codec, such as H.264, reduce bandwidth traffic load but at a cost of more storage and command center processing? Can the budget afford the increased transmission and storage associated with megapixel cameras?
Storage and Retrieval Challenges
Though being analog-based, most homeland security organizations already have digital and network video recorders for storage and retrieval. However, storage solutions have their own challenges, thanks to myriad features and benefits that can range from common specs to helpful elements such as intelligent PTZ control with preset positions and e-mail or SMS message notification upon motion detection or event alerts.