The physical topology of CCTV system designs is undergoing some exciting transformations today. Until the last 20 years or so, CCTV designs really hadn't changed much. However, the events of the last couple of years have created a need for more sophisticated CCTV system designs on the market. Companies are converging their networks so that IT infrastructure serves as part of the CCTV network. They are demanding that integrated systemsÃ¢â‚¬â€CCTV, access control, biometrics, building automationÃ¢â‚¬â€be made available over the network. They want secure network access to recorded and monitored video from a common database.
The traditional analog CCTV designs cannot accommodate all of the new products and technologies being incorporated into video surveillance solutions. Newer, more innovative video surveillance designs have been created to accommodate some of the latest trends, products and technologies being deployed in the marketplace, including
Ã¢â‚¬Ë˜ digital IP cameras and a large installed base of analog cameras
Ã¢â‚¬Ë˜ high-bandwidth networks and wireless LANs
Ã¢â‚¬Ë˜ handheld communication devices integrated with video surveillance
Ã¢â‚¬Ë˜ mass storage solutions
Ã¢â‚¬Ë˜ higher-quality video cameras
Ã¢â‚¬Ë˜ Web/XML applications.
Basic Questions to Consider
Before exploring some of the new video surveillance system designs, let's review some of the basic questions you should be prepared to answer prior to purchasing a new video surveillance system or working with an integrator or distributor on a video surveillance system design.
Ã¢â‚¬Ë˜ What specific organizational or departmental goals would you like the surveillance system to address?
Ã¢â‚¬Ë˜ What business issues would you like to address (i.e. security, liability, theft)?
Ã¢â‚¬Ë˜ If you currently have a video surveillance system, what have you liked and disliked about it? How happy have you been with the integrator? How many monitoring hours are currently being used? How much manpower is necessary to effectively use the system?
Ã¢â‚¬Ë˜ Do you plan on monitoring your video surveillance system over the IP network?
Ã¢â‚¬Ë˜ Do you plan on integrating your video surveillance systems with other security systems, such as access control, fire or burglar alarm?
Ã¢â‚¬Ë˜ Do you have a specific video surveillance manufacturer or group of manufacturers in mind or do you need assistance evaluating your options?
Having the answers to basic questions similar to the ones above can help with your site survey and ensure that your CCTV purchasing process runs smoothly. A site survey will need to be conducted at your location in order to determine the appropriate products required to meet your needs. Integrators, architects, consultants, engineers and value-added distributors are available to assist you in making the right choices for your surveillance system design.
Designs That Make The Grade
It's important to design a video surveillance system that meets your needs today and well into the future. You want to purchase a solution that not only provides a great return on investment in the future, but that is also able to accommodate future products and technologies as they emerge. Below are some recommendations to make to your integrator or distributor to ensure the video surveillance system you choose meets all your requirements.
1) Select a video surveillance cabling infrastructure that can support tomorrow's technologies (i.e. new and emerging digital and IP-based technologies).
2) Choose DVRs over VCRs in your video surveillance system designs. Why? A 50GB hard drive in a DVR can store the same number of images as 10 VHS tapes.
3) Determine if you will implement an analog, digital or IP-only system. If you are interested in implementing a proactive, preventative video surveillance system, you should choose a digital system. Among other things, digital systems allow for content analysis, which provides you with searchable access to the valuable data and information your system is monitoring.
4) Video surveillance is migrating towards the network. A parallel video surveillance network, one that adheres to standards in network cabling, is recommended in addition to your data network.
5) When considering IP/digital video, choose a file transfer and compression technology that provides you with the image quality you require. Be sure to implement a standards-based, open file format.
6) Partner with a company that understands the latest products and technologies in the video surveillance market and can help you make informed decisions about your video surveillance purchases.
Next, we'll take a look at the traditional CCTV coax-based system designs and explore some of the newer, more innovative approaches being implemented today.
Video Surveillance Designs for the 21st Century
As the video surveillance industry evolves and new digital and IP-based technologies are developed, the cabling infrastructures that support these advances must also evolve. As an end user, you have several decisions to make when it comes to selecting the infrastructure to support your video surveillance system. These decisions can be very difficult to make in an industry that is going through rapid change. Today, video surveillance infrastructures range from cabling systems such as traditional coaxial and multi-conductor cables, to unshielded twisted pair (UTP) solutions, to wireless infrastructure solutions. As a result, the biggest challenge faced by end users is selecting a video surveillance infrastructure that is cost effective, provides room for future growth and offers the ability to migrate to future technologies. The following overview of the various video surveillance infrastructures that exist today will help you choose the solution that best meets your current and future needs.
Traditional infrastructures have been the main distribution media in the video surveillance market for the past 20 years or so. These infrastructures basically involve sending video signals over a coaxial cable like RG59 or RG6, while power and control data are sent using multi-conductor cables such as two-conductor 18 AWG.
Currently, there are two methods of installing traditional infrastructures.
Ã¢â‚¬Ë˜ Home run approach. The most popular way of installing traditional infrastructure is to use bundles of "home run" cabling from every camera to a central security head-end location where monitors, controls and recording equipment are maintained.
Ã¢â‚¬Ë˜ Star wired approach. A "star wired" traditional infrastructure is not a commonly used design, but it does tend to be a more maintenance-friendly design. Rather than using home run cables, the star wired design uses wiring closets where the cable runs from each camera are terminated into a BNC patch panel. From there, bundled coaxial and multi-conductor cables are run in a backbone design to the security head end. The cables are finally terminated into another BNC panel for breakout to recording and monitoring equipment.
The drawback of implementing a home run cabling system is that there are no national standards for cable distance, installation practices or cable performance. A lack of standards permits poorly installed or poorly designed infrastructures. Video signal noise, power phase differential and unintended ground loops can be the result. Electromagnetic interference, unsynchronized power and ground loops are common in traditional video surveillance infrastructures and will result in video signal noise and loss of image quality.
Traditional infrastructures were also designed to support only 75-ohm analog video surveillance technologies and do not provide a migration path to future 100-ohm IP-based technologies. These traditional infrastructures are still popular in the video surveillance industry today. However, as more and more IP-based technologies appear, the need for traditional infrastructures will rapidly decrease. According to security industry researcher JP Freeman, 30 percent of video systems were connected to the LAN in 2002. In 2007, it is estimated that 71 percent of video surveillance systems will be connected to the LAN.
Wireless video surveillance infrastructures are perfect for customers that have widespread, multiple remote or mobile locations that are scattered throughout a town, city or large campus area. Wireless video provides a cost-effective method of distributing video signals over the air at great distances and in mobile applications where it is either too expensive or too difficult to install a cable infrastructure.
In a crisis situation, first responders can use wireless video infrastructures to send and receive live streaming video and mission-critical data simultaneously from their vehicles and in command centers. Wireless video infrastructures can also be used by corporations or educational facilities that may have deployed surveillance cameras at multiple sites throughout a city.
Wireless infrastructures work through receivers and transmitters that are mounted on buildings, water towers and other high structures to permit optimal communication between receivers and transmitters. Today, wireless infrastructures are capable of transmitting video surveillance images beyond 50 miles to recording and monitoring equipment.
There are two main types of wireless infrastructures.
Ã¢â‚¬Ë˜ Point to point (PtP). This is a wireless infrastructure that uses only one transmitter and receiver. Point-to-point infrastructure is perfect for a single-camera scenario or a grouping of several cameras from a single location tied through a network.
Ã¢â‚¬Ë˜ Point to multipoint (PtMP). Point to multipoint uses multiple transmitters and receivers. This type of infrastructure is perfect for large-scale video surveillance systems that have a deployment of cameras in multiple locations either mobile or stationary.
Fiber-optic video surveillance infrastructures are perfect solutions for camera installations that exceed the distance limitations of coaxial and UTP cabling. These systems use either multimode or single-mode fibers to transport video images and control data from cameras to recording and monitoring equipment. Fiber infrastructures use various multiplexing electronic devices to convert video and data signals into optical signals at the camera site or in wiring closets. The video and data signals are then reconverted back to either 75-ohm (traditional) or 100-ohm (digital/IP) signals in the security head end for connection to recording and monitoring equipment.
Long-haul fiber solutions are very popular with transportation departments. Many highway and tollway authorities use fiber solutions to monitor traffic through video cameras. These solutions are perfect for customers who have large LANs and WANs.
UTP infrastructures are beginning to emerge and become a major support infrastructure in the physical security industry. These infrastructures are ideal for supporting both legacy analog systems and digital/IP-based video surveillance technologies if properly designed to data transport standards.
There are many ways to use UTP infrastructures to support IP-based technologies.
Today, there is a small group of customers that use their current data network infrastructure to support IP cameras and various other IP-based technologies such as network monitoring equipment. Basically, the new IP-based devices act as any other node or workstation on your network. They fit right into an existing Ethernet network by simply plugging into an open port. Usually, a new horizontal run of cabling will need to be run so cameras can be placed high on a wall or in a ceiling. Such cameras should be powered locally.
Data networks can also be used to support existing analog technologies through the use of video baluns that convert 75-ohm analog video signals to 100-ohm video signals for distribution across an existing data network. The major drawback of putting IP cameras on an existing UTP network is the amount of bandwidth consumed by IP cameras. A parallel network is recommended to segment the bandwidth requirements of the video surveillance network from the data network.
Another type of UTP replacement technology being installed today replaces the coaxial cable with a pair of UTP cables. This reduces the installed cost but doesn't support Ethernet-based IP devices such as cameras or servers, which require high-performance four-pair UTP cables that meet industry standards such as TIA/EIA-568B.
Closed circuit twisted pair (CCTP), addresses the standard's requirements for data capabilities. CCTP, by Anixter, is a new method of transporting video, data and power signals over unshielded twisted pair (UTP). CCTP was designed to provide a video surveillance infrastructure that can address current technology cost effectively, while supporting migration to rapidly evolving IP-based surveillance systems.
As you can see, the video surveillance market is undergoing some dramatic changes. There are many resources available to assist you in making informed decisions about your next enterprise video surveillance system. Partner with companiesÃ¢â‚¬â€integrators, value-added distributors, industry trade associationsÃ¢â‚¬â€that understand the latest products and technologies in the video surveillance market and can help you make informed decisions about your video surveillance purchases.
Pete Lockhart is vice president of new technology with Anixter Inc. He was instrumental in the creation of the original Anixter Levels Program in 1989, and helped to create the Level 5 cable concept in 1991 that led to the Category 5 cables in the current ANSI/TIA/EIA-568-A Standard. Mr. Lockhart is a member of BICSI and the IWCS Symposium Committee, and past member of ACUTA, HIMMS, ATM Forum and EIA/TIA.