Linking into a system from a remote site is no longer the frustrating issue it once was. Most systems in the marketplace are capable of remote connection, it is the degree of connection and what this offers that now makes the difference.
Check out the full capabilities before you purchase your system as there is a tendency for sales people to say that all systems are the same and offer full access - you pay for what you get.
Bandwidth issues
'The size of the pipe' is the simplest way of understanding remote site video surveillance. If you have a 56 k/bits Public Switching Telephone Network (PSTN) connection ie an ordinary standard modem connection through normal voice copper telephone wire, then this a 'pipe' of a certain diameter which allows through a certain amount of information per second. In this case 56 Kb; there are 8 bits in a byte, therefore our 56 Kb must be divided by 8 to give a figure of 7 KB, a term we are more used to seeing and using. So, if one has a video frame of 7 KB, it is reasonable to assume that one frame will be transferred each second (this is a general concept as there are other factors to be considered).
Similarly, the same rules apply for a 64 Kb integrated services digital networks (ISDN) line giving a pipe size of 8 KB, and a 128 Kb ISDN giving 16 KB. At the time of this publication the new asymmetric digital subscriber line (ADSL) will be launched by Telkom, offering downloading speeds of up to 1,5 Mb and uploading speeds of up to 512 Kb with the G.lite version and then download speeds of up to 8 Mb and uploading of up to 640 Kb with the full rate G.dmt ADSL. What I am saying is that new developments will give very much enhanced options with remote video surveillance, but remember that the fastest point-to-point speed available on ADSL will be 640 Kb or 80 KB per second as the smallest part of the pipe.
Application theory
Now that we understand a little more about what we are transferring through (the pipe) we can look at how this might help our specific requirements. There has been significant growth of TCP/IP cameras transferring a full image over a network to a central point; if we are using a single camera from a point-to-point basis then this should work well with the current 'pipes' available. Remember that the image is transferred in a very limited compression format giving a fairly large per-frame size, meaning that your pipe is filled very quickly. Adding a second and third camera then starts restricting, data flow.
As a result there is still a requirement for on-site recording if you are looking at utilising a full range of 8, 12, 16 or more cameras. This allows selective viewing of key event cameras whilst being assured that other incidents are being covered by recording on site. Post-event download is then easily carried out through file transfer protocol (ftp) transfer allowing for playback at the speed of local recording. Further analysis can then be achieved off site, allowing for digital enhancement, snapshots and printing out of key scenes all in the main control room.
Digital video recorders (DVRs) have come a long way in recent months and most will offer the basic options of live viewing and ftp transfer. Developments are now moving forward to the ability to remotely control all aspects of the DVR from a remote control room: alarm triggers, PTZ control, frame rate adjustment, changing daily schedule planners, instigating new alarm set-ups, remote audio, passwords, and many other features. For example, the SecureVu VC 2000 has now expanded its abilities with a new remote station including a number of individual server modules, an expanded remote module and then ftp/http Web browsing for full control of key utilities functions.
Add to this the open architecture ability of a nonproprietary PC-based system and you can link into full management systems allowing total remote control room integration with all of your on site requirements. With VC 2000's integration into the Pen Control Management Information System (MIS), key security controllers are now able to respond to an alarm, follow a set course of actions while monitoring the situation, and full post-event audit trails to check back on response times and the effective resolution of the event at hand.
British Telecom implemented a total upgrade of its security utilising the Pen Control system encompassing over 6000 sites, reducing their security manpower from over 12 000 security officers to less than 300. This alone has resulted in a cost saving of over 12 million pounds sterling over two years. BT's management no longer view security as an expense but see it rather as an asset. Future local developments will see Pen Control installed in a number of prominent Blue Chip organisations. The system will incorporate a total remote video surveillance solution for over 100 sites integrating all SecureVu VC 2000 operations. In addition the non-proprietary nature of Pen Control will further incorporate access control, building management, fire control and many other key features.
Conclusion
Remote video surveillance has moved a long way over the past two years. Integration is now the name of the game; do not restrict yourself to purely a simple remote dial in, unless that is all you need, but look at the scalable options you now have. Open architecture is the way forward. Integration of nonproprietary systems will give you the flexibility to plan your budgets in line with your key needs. Add to this the options for hardware and software upgrades, as well as a progressive roll-out of your security and management needs, tied in with a clearly structured bandwidth policy and you will have remote video surveillance second to none.
For more information: Niall Beazley, Vision Catcher 011 465 6396, [email protected]
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