Bandwidth Math for City-Scale Wireless Digital Video Surveillance Systems with Many Cameras per Square Mile

THE OPPORTUNITY AND THE PROBLEM

Outdoor video surveillance is a communications problem, first, and a video problem, second. -- Steve Morton, Boundless CEO

Demand for outdoor video surveillance cameras to fight drug crime, street gangs and terrorists is exploding. Major communications providers who previously resisted providing city-scale and municipal-scale wireless Internet access are now moving aggressively to provide it. Leveraging the use of large, public wireless networks for video surveillance for public safety has the potential to drastically reduce the cost of providing outdoor video surveillance. Cost reductions of 75% or more are possible using Boundless' unique technology.

Unfortunately, few system architects appreciate the complexity and difficulty of operating video surveillance cameras over wireless networks. Even a small number of video surveillance cameras alone per square mile can use all of the wireless capacity usually provided for end-users to access the Internet, nullifying the revenue-producing capacity of the network.

The critical issue is to ensure that the "Bandwidth Balance Sheet" works. One must assess how much usable, revenue-producing, wireless communications capacity, i.e., bandwidth, per square mile, the asset, is available. One must deduct how much communications capacity per square mile is required for video surveillance, the (expense), so that the bottom line result provides sufficient capacity for paying customers to access the Internet.

Fortunately, city-scale and municipal-scale wireless networks CAN provide end-users access to the Internet as well as comprehensive, city-scale outdoor video surveillance IF Boundless' unique, ultra low bandwidth, video surveillance products are used and the Bandwidth Math is done right.

Not just an incremental improvement over conventional technology, Boundless Security Systems, Inc. (www. BoundlessSecurity.com ), in Newtown, CT has made a breakthough in the ability to economically handle hundreds of outdoor cameras per square mile without hopelessly flooding wireless networks with video. And, Boundless also enables the latest, multi-mega-pixel, High Definition TV cameras to be used for sharp images over large fields of view, rather than limiting cities to Standard Definition CCTV cameras that use 50-year old video technology.

The following drawings give details of the Public Safety application, competition, and Boundless and its unique solution:

1.  Ultra Low Bandwidth, Boundless Security System™ solves cities' video bandwidth problem, enabling public wireless networks to handle large numbers of surveillance cameras

2.  Ultra low bandwidth, Boundless Security System™ provides continuous, wireless, real-time remote access to live and recorded mobile video surveillance in patrol cars

3.  CASE STUDY: Comparison of wireless, ultra low bandwidth, IP-based, Boundless Security System™ digital video surveillance system with wireless IP camera system

4.  Boundless' Storage Operating System™ provides ultra low bandwidth, hybrid wireless outdoor digital video surveillance systems with the best of DVR and NVR capabilities

BANDWIDTH MATH REQUIRED FOR SUCCESS

Here's the Bandwidth Math for wireless video surveillance in a nutshell. It's in the context of a hypothetical city-wide WiFi wireless network for a small city in the USA:

Public wireless networks typically provide 10 to 15 Mbps per square mile of communications capacity. We optimistically assume that this entire capacity usable and that it is available for either upload or download. However, only about 1/3 of this capacity may be usable in a peak usage situation, and some networks have much lower upload speed than download, and video cameras require upload speed. Ideally, this much capacity can service about 100 to 150 typical users per square mile with speeds comparable to wired broadband speeds. Each user's wireless traffic ebbs and flows, depending upon the information they're accessing at any given instant in time.

Conventional outdoor IP-video streaming using Standard Definition TV cameras requires 2 to 3 Mbps per camera continuously using MPEG-4, a leading form of video compression. Rather than ebbing and flowing like users' access to the Internet, conventional IP-based, outdoor video surveillance systems create continuous wireless traffic since it's required for continuous remote recording. Using emerging High Definition TV cameras would require 6 times this much data.

Suppose the small city wants an initial 7 cameras in a square mile for public safety. This is a very small number of cameras per square mile. More about this later.

Here's the bandwidth problem:

7 cameras x (2 to 3) Mbps/camera = 14 to 21 Mbps of continuous uplink wireless traffic just for the cameras alone. This is 100 to 150% of the TOTAL wireless communications capacity per square mile that's usually available.

There are two solutions:

1) Cities can install a dedicated, extra high speed, wireless network just for outdoor video surveillance. This is what New Orleans did two years ago at great expense. It also means that (a) mobile police officers will have a hard time accessing the video due to the high bandwidth required for mobile access, (b) wireless networks have to be custom-designed for each specific camera placement, (c) it's not practical to move cameras around depending upon where recent crimes occurred, and (d) it's not practical to have live video feeds from mobile vehicles.

Or,

2) Cities can use Boundless' ultra low bandwidth, multi-stream, IP-based, digital video surveillance system with its Storage Operating System™ instead of a conventional, IP-based, video surveillance system. Boundless (a) reduces wireless video traffic by 99% without sacrificing the quality of recorded video, (b) makes it easy for mobile police officers to access live and recorded surveillance video, (c) makes it practical to temporarily place cameras where recent crimes occured, (d) makes it practical to provide multiple live and recorded video feeds from police and emergency vehicles, and (e) makes it possible to remotely and centrally archive the recorded video during offpeak hours for vast storage capacity.

How many cameras would one use to protect a city if communications bandwidth weren't a problem ?

If one places one stationary camera to watch each street at an intersection, then one needs 100 to 400 cameras per square mile because most cities in the USA have 100 to 400 blocks per square mile.

An alternative is to use one pan-tilt-zoom (PTZ) for every 4 to 8 city blocks. The problem is that a PTZ camera is like a telescope, and the chance that it's looking in the right direction at the right time is slim. In addition, the constant movement of a PTZ camera makes it impossible to use image analytics / content analysis software to automatically "watch" the video for certain threats so that people don't have to constantly watch the cameras.

Ideally, one should pair an ultra wide angle, fixed camera for full situation assessment with each PTZ camera. A 4-way intersection would need four cameras, two ultra wide angle cameras and two PTZ cameras. One ultra wide angle camera and one PTZ camera would look up the main street, and one ultra wide angle camera and one PTZ camera would look down the main street. Thus four cameras are required at each intersection.

CONCLUSION

Demand for outdoor video surveillance cameras to fight drug crime, street gangs and terrorists is exploding.

Operating video surveillance cameras over city-scale and municipal-scale wireless networks is complex. City-scale and municipal-scale wireless networks CAN provide end-users access to the Internet as well as comprehensive, city-scale outdoor video surveillance IF Boundless' unique, ultra low bandwidth, video surveillance products are used and the Bandwidth Math is done right.