Going Mobile with Video Surveillance on Chicago's Bus System

As surveillance video has grown increasingly popular, it's popped up in more and more everyday places. It watches the cashier in fast-food restaurants. It captures identities of customers at convenience stores. It watches from the corners of downtown office buildings. It pans, tilts and zooms from dome cameras mounted on lampposts in urban districts.

It's even been found to some extent on transit system buses, though a mobile bus system has always presented a unique challenge. First, only today's newer buses have cameras built in (like the one's Bombardier is providing to Toronto's transit system -- see story); the others require time-consuming retrofits. Secondly, bus systems need to be "hardened" type systems to deal with the rough city streets, so not just any mounting system and DVR will do. And finally, the problem has always been that the video resides on the bus, making it a time-consuming and sometimes labor intensive task to take video off the bus. It's complicated by the fact that buses are designed to spend their time on the streets, delivering passengers, rather than back at a bus depot, downloading video via a network cable.

That's the situation that Christine Beaudin, principal of network services for IBM, found when IBM landed a $2.4 million project with the Chicago Transit Authority. IBM was selected to be the networked services and security integrator for the beginning of a massive mobile bus security project that would eventually place cameras on all of the city's buses. But it wasn't just a job of wiring up cameras to DVRs -- that was already done. Chicago's Transit Authority wanted the video to be useful; it wasn't good enough for the video to simply sit on the bus as an archive of the incident. The CTA and Chicago's police representatives wanted to be able to access the video in real-time if an incident was occurring.

It patterned well with what Chicago and Illinois' Cook County area was already doing in high-crime areas with its "eyes in the sky" street cameras and gunshot detectors that fed to a police monitoring station. The problem, of course, was how to make that video accessible.

That's where IBM network services crew stepped in, headed up by Beaudin and her team.

"Essentially what the CTA is trying to do is to build a broadband system across the city in order to be able to provide video surveillance on all the buses," explains Beaudin. "They currently have over 600 cameras across the bus and rail systems, and 400 cameras in the bus system itself. Right now the video is local to the bus itself, and what they wanted to do was provide connectivity back to the main central office so they could be more proactive and be able to work closely with the Chicago Police Department, so if there is an incident, they can react more quickly."

Fortunately for IBM, the new buses coming online with the CTA were being delivered with cameras, and some of the old buses had been retrofitted. Most of the buses have between four and six cameras, so there was no shortage of available video, whether that was looking forward at what the driver sees, or looking back into the bus where the passengers were seated. Many of the cameras are capturing 30 frames per second, but according to Beaudin the system is designed such that the recorder on the bus may capture 30 fps on all the cameras, but due to bandwidth limitations, they may only push 10 fps over the wireless network.

Thus, IBM's part of the project was to build out a broadband 4.9 Ghz and 2.4 GHz wireless infrastructure so the CTA could connect with the surveillance video it already had. According to Beaudin, their task was to add wireless nodes to the buses and to initial fixed-installation sites, such as a bus terminal.

Then, says Beaudin, with the buses wired up for cameras, recorders and wireless nodes to transmit video, the Chicago Police vehicles were also set up with mobile access routers from Cisco and Panasonic's Toughbook computers so they could connect to a bus if they are in the vicinity.

"Those mobile access routers," says Beaudin, "shake hands to say, yes, you are allowed to see that video. And essentially what happens is that the police responder's vehicle becomes another node on the network."

Then, once they are connected to a bus, the responder can select which cameras they want to see. And while the network connectivity is off to a great start, the software for viewing the system is still in development, says Beaudin, who notes that her department has traditionally worked with an Insight or Genetec surveillance software package.

But the solution doesn't come without challenges, and it's not an instantaneous solution.

"It teaks a lot of time to deploy a wireless network," explains Beaudin. "It's not like a cellular phone. A lot of people think that once you put a router in a bus you can automatically connect and start receiving and sending data, but actually you have to have a connection outside of the bus to start sending video data back to the central office. And obviously, Chicago does not yet have the infrastructure -- the wireless "cloud" -- across the entire city. So until that happens, what the CTA has to do is that they have to go to a bus terminal where we have also installed another 4.9 Ghz radio and then they can communicate that video from the bus through the terminal connection and back to the central office.

"The eventual dream is that they're going to be able to communicate [video back to the central office] from anywhere in the city, but for the time being, they have to go from bus terminal to bus terminal."

Fortunately, the wireless hotspots are growing. As of late December, there were 39 bus connection hotspots, and Beaudin hoped that number could double soon. For some of the bus lines that means a wireless connection about every 10 minutes -- so while it's not an always-on connection like a cell phone, the infrastructure is being planned to eventually reach that goal. It's aided by the fact that there's a fiber optic system built alongside the rail system. That trunk will be a core backbone of the system, says Beaudin, when the network of wireless hotspots is fully built.

In the first phase of the hotspots connection that IBM is building, the buses will have to pause at those terminal to let the video download, but Beaudin says that in a later phase, IBM will connect all of the terminals and then create a wireless mesh among those hotspots so that the buses wouldn't have to pause to transfer video, but that the system would simply pick back up downloading at the next hotspots where it left off at the previous hotspot.

Of course, not all of the video will have to be downloaded on the wireless mesh. The camera and DVR system is designed to delineate between important video and unimportant video. For example, if the bus driver applies the brakes strongly, the system buffers back before that application of the brakes and records the video coming up to that and for a specified period of time after that. And if an incident is happening in the bus, the driver (who can have a view of the video as well) can select a panic button to mark the video as "of interest".

And while the implementation will take time -- the initial installation for this pilot project was finished in October 2006 and will stay in pilot mode for about four months -- it's a start of a model for a wireless system that could become applicable for not only all manners of transit system, but also applicable for mobile security forces. Eventually the system should cover the CTA's 2,100 buses, so it clearly is a full-scale, real-world test of how to make mobile surveillance work. And as the project expands to the Chicago rail transit system, it will have to solve even more unique connectivity challenges like getting individual train cars to work together like a single unit in a mesh framework.

But as Beaudin notes, the project, while driven by security and police, is not just about adding security technology and exploring new system design avenues.

"The biggest thing about this project is that they want their riders to feel safer, and that will help increase ridership."