The Mumbai Metro is deploying a realtime, mobile wireless video surveillance network, the first transit agency in India to do so. The network will broadcast text messages and provide onboard video surveillance to passenger information displays.
Currently under construction, the three-line, high-capacity rapid transit system will span 40 miles in Mumbai, the financial capital of India. The first phase of the metro is scheduled to be completed in 2010. Thales Portugal has been tapped to provide the required communication systems, which will include wireless infrastructure mesh technology. The evaluation and field testing period was extensive.
To build a real-time video surveillance network, wireless mesh nodes will be placed on the trains, as well as along the tracks at intervals of 500 meters. The system will allow 10 MBps speed between the train and ground nodes at all points of the track at a speed of 50 mph.
Eighty-eight percent of the Mumbai population takes public transportation. In recent years, the city’s popular Mumbai Suburban Railway has become a magnet for terrorist attacks, hence the Mumbai Metro designers’ desire to protect the passengers, identify culprits in real time and ensure the fastest possible response should man-made or natural disasters occur.
Since 2003, Mumbai Suburban Railway has suffered eight blasts and at least 318 people are believed to have died as a result:
•March 14, 2003: A bomb went off on a train in Mulund, killing 10.
•July 11, 2006: A series of seven bombs went off on trains, killing 207.
•Nov. 26, 2008: Chhatrapati Shivaji Terminus was attacked, killing at least 10 people.
Potential terrorism aside, the system also will support day-to-day operations of the metro and will discourage vandalism, tagging and other undesirable behavior on the trains.
Seoul Subway: a Pioneer in Wireless Mobile Video
After 198 people perished in the Daegu, Korea, subway fire of 2003 -- when an arsonist set fire to a car train stopped at the Jungangho station and the blaze spread to a second train -- officials began investigating real-time wireless video surveillance systems as a means to help protect subway riders and transit workers against potential fires, accidents, thefts and other harmful incidents.
Seoul Metropolitan Rapid Transit Corp. wanted a system that provided train operators live video of station entrances. That way, a driver could decide not to enter a station in case of accidents or other problems such as a person on the track.
The ability to stream video from a station’s cameras to a monitor on a train moving at speeds of 50 mph was critical. Wireless mesh technology was the only option to transmit video to and from subway cars, as it provided seamless hands off and roaming along the fixed wireless infrastructure.
SMRT’s planned network will provide video surveillance from the inside of passenger trains to a monitoring center video streaming of public announcements and commercial advertisements onto passenger train monitors. A total of 1,000 mesh nodes are being deployed for all four of SMRT’s subway lines, along with 350 cameras in the stations and 300 in the trains. The wireless infrastructure delivers 20 MBps of capacity, enabling real-time streaming video to and from the trains moving at 50 mph.
Wireless Ad-hoc Video
Massachusetts Bay Transportation Authority, the fifth-busiest transit system in the United States, transporting nearly 1.2 million passengers daily, implemented a wireless surveillance system combining on-board cameras and video recorders with wireless mesh networking for real-time ad-hoc connectivity. The $1.4 million project, partially funded by a Department of Homeland Security grant, called for the installation of onboard surveillance systems on 155 new buses.
The solution enables transmission of live video feeds to laptops in MBTA police officers’ networked vehicles, allowing first responders to view an onboard incident as it unfolds, in real time. Responders can now plan and execute tactics faster and smarter, enhancing the safety and security of passengers, officers and transit staff alike.
The MBTA busses are equipped with eight cameras: four inside and four outside. Inside each bus, two cameras are mounted near the ceiling at each end of the aisle and look down the aisle. The other two cameras watch the two doors and record people getting onto the bus. Outside the bus, one camera looks straight ahead to capture accidents that may occur.
On the curbside of the bus, a camera watches people getting on and off. A roadside camera looks for accidents, and, finally, a camera on the rear of the bus monitors the back.
The wireless video network operates in the 4.9 GHz spectrum, which is designated by the FCC for public safety and provides secure connectivity for first responders.
Technology Behind Real-time Mobile Video
Real-time video is what a lot of transit agencies and industrial companies are looking for because it allows officials to view a situation as it unfolds to know what’s ahead. Mobile real-time video is the wave of the future -- for city-wide public safety and industrial, campus, mining and transportation applications.
Wireless mesh maintains real-time connections between fixed and mobile nodes moving at high speeds -- without dropping packets and introducing latency or jitter. Additionally, mesh supports real-time video streaming and VoIP for infrastructure mobility and challenging environments, unlike Wi-Fi, which supports only low-bandwidth data.
Similarly, users cannot truly implement mobility with point-to-multipoint equipment because of the central command- and-control architecture, which does not allow for roaming. Mesh, with its distributed architecture and intelligence, can support mobility within the mesh, and even roaming across multiple meshes.
Real-time Video, New Trend in Transit?
So is this a trend for transit security? Transit agencies are not only deploying cameras on trains and busses, but also implementing real-time video streaming to and from moving trains, buses and shuttles.
There are interesting parallels between the Seoul and Mumbai rail system deployments. Rail systems have the necessary right-of-way for the deployment of fixed infrastructure. Both systems have fiber along the tracks, so engineering and cost-justifying the systems is easier, as they “only” need to deliver the “meshing” capability between the fixed infrastructure and the mobile mesh nodes.
Apart from security and safety, the traveling public today expects more than a comfortable ride. It expects to stay connected while on board trains and busses. Wireless access solutions can bring Wi-Fi connectivity to passengers. The same infrastructure deployed for video can serve double duty and provide the backbone for Wi-Fi traffic, which tends to have much lower bandwidth requirements compared to video and does not require real-time connectivity in most cases. Once passengers have access to Wi-Fi, they may want to conduct Skype VoIP calls or conduct video conferencing on their smart phones.
It’s not surprising that the first realtime video surveillance deployments are being rolled out in subway and light rail systems. The Seoul subway system takes advantage of the existing fiber assets to place the fixed mesh nodes so that the wireless connection is dedicated to transmitting a wireless signal between the fixed and mobile nodes.
In contrast, a real-time video system on busses requires deploying mesh infrastructure along the bus routes, which establishes the wireless backbone for communicating the signal coming from the bus back to the command center. Eventually, as wireless technology advances, these projects will become feasible to transit agencies outside of major metropolitan centers.
Transit agencies do not have to wait for grants to deploy a full-fledged, mobile- to-fixed real-time video infrastructure for wireless capabilities. Using the inherent capability of wireless mesh to establish ad-hoc self-forming connections, as illustrated in the MBTA application, agencies can simplify retrieval of recorded video when busses pull into the depot.
The system provides fast and secure data download when busses arrive to the depot. Communications provide trip data including distance and G-force data -- breaking, turning, starting forces -- as well as video surveillance recordings.
When implemented as a peer-to-peer mesh network, the system supports not only data transfer from busses, but data transfer in the other direction, from the depot to the bus.
Author: Ksenia Coffman, Firetide