IP Case in Point: Wireless to the Rescue

Advances in video surveillance and IP-based network cameras are opening doors to wider adoption. Municipalities and government agencies, along with transportation, education and retail industries are not only implementing sophisticated IP-based network systems because they increase public safety and security, but these advanced systems also provide greater scalability and flexibility, enabling companies and organizations to expand their surveillance capabilities as their needs and environments change. Wireless networks are just one of many advancements changing the landscape of IP surveillance.

As indoor and outdoor IP surveillance networks within buildings and city centers are becoming more common, companies and organizations are finding that non-wired solutions are increasingly appealing. Wireless solutions offer financial benefits, increased functionality, greater flexibility, and are typically quicker installations than more traditional wired installations. The combination of these benefits was exactly what the City of Savannah, Ga., needed as they faced a difficult installation due to time constraints and tricky environmental obstacles.


Savannah Charm Turns Into a Challenge

The City of Savannah exudes old Southern hospitality with its historic town squares, colonial homes, cobblestone streets and lush foliage. Unbeknownst to many people, the features that create so much of the town's charm presented great challenges to local police, who wanted to install a surveillance system for the city's upcoming St. Patrick's Day celebration.

Savannah is home to the second largest St. Patrick's Day parade in the United States , welcoming more than 700,000 people into the city to experience age-old traditions of song and dance. While thousands of residents and visitors were coming to enjoy the city's picturesque landscapes and renowned celebrations, city and public safety officers were focusing on IP surveillance efforts in order to keep danger at bay.

Savannah presents a challenging environment because of its marshy coastal lands and low-hanging trees in addition to several canals, which run throughout the city to alleviate flooding. Savannah is the state's oldest city with limited power sources, older building structure and buildings that vary in height. These unique set of circumstances posed unique difficulties when the city was considering installing a surveillance system for the 2007 St. Patrick's Day Parade.


A Solution With No Strings Attached

The city's public safety officers decided to install a temporary wireless IP surveillance system to increase public safety during the celebrations and help public safety and emergency personnel police the streets more effectively. Savannah officials first started using network video solutions in 2004 when the G8 Summit was held in the city; however, the system was considered impractical due to the slow speed of cable modems and the limitations on where cameras could be installed because of older city layouts and streets. A wireless surveillance system was a much more practical solution for the city because of the speed with which they needed to have their surveillance system up and running and because of the scalability it provided officials who could change the system easily for future events.

There are two categories of wireless communication, Wireless Local Area Networks (WLAN) and wireless bridges.

WLAN are designed to work over short distances and generally indoors including indoor gathering places like community centers, sports arenas and large office spaces. WLANs work best in these types of locations because it allows for the installation of cameras without having to run additional cable through the walls and ceilings. In addition, WLAN systems make a wireless surveillance system within a facility, such as retail outlet, highly functional. Cameras can easily be moved to new locations on a regular basis without having to pull new cables with each change, making it very flexible.

Wireless bridges are generally used in outdoor situations and are becoming more common in city surveillance efforts. Buildings and sites can be connected through point-to-point data links capable of high speeds and communication over long distances. Commonly used technologies include optical systems such as laser links, and radio frequency such as microwave links. For locations that are outside of the range of laser or microwave links, users have the option to connect wireless networks systems through satellite communication.

One way of using a wireless bridge is through a wireless mesh network, which is what Savannah used in its IP-based surveillance operation. A wireless mesh network offers multiple point-to-point data links creating a larger network within a well-defined area. Many cities are beginning to use wireless mesh networks as the framework for the communication networks. By establishing private wireless bridges that use radio frequency, cities have the ability to create secured wireless networks for city government use and city surveillance.

Wireless mesh technology is also easily scalable and reliable. The technology is based on nodes that transmit data to other nodes. Each wireless node is connected to the network. If one node drops out, the transmitted data is sent to the next available node and the system remains intact. Plus, additional nodes can easily be added to existing systems.

Wireless mesh systems function well in difficult environments and offer practical solutions for cities like Savannah looking for coverage in challenging environments and rough terrains. Because wireless mesh systems do not rely on existing infrastructure and the labor intensive installation of cabling through city centers, they can easily be set up for permanent and temporary surveillance efforts.


Fast and Flexible Installation

Three-months prior to the St. Patrick Day Parade, Savannah officials discussed the possibility of creating a temporary wireless surveillance installation with systems integrator NetMethods.

City leaders had partnered with the Louisiana-based company on a previous wireless network installation in a small area of town just a few months prior and experienced initial success. They wanted to continue that success and build a larger wireless system that would scale to the project at hand – and quickly as the Parade was around the corner. One-month prior to the Parade, Savannah officials approved the wireless surveillance project, and NetMethods began an accelerated planning schedule for wireless installation.

The target area for the proposed temporary wireless installation was the historic Riverfront area and its side streets. NetMethods worked with its partner, Tropos Networks, and designed a system that overlaid Axis Communications wireless network cameras on a Tropos MetroMesh network. The installation included the AXIS 232D, a network pan/tilt/zoom (PTZ) dome camera with day and night function; the AXIS 221, a fixed-view network camera with day and night function; and the AXIS 214, a PTZ network camera. The project ran on On-Net Surveillance Systems Inc. (OnSSI) software and tapped directly into the City of Savannah 's core PC servers for video management. Police officers and public safety officials were able to remotely view surveillance footage through IP-enabled laptops in squad cars or by logging on with computers to a secured connection. In addition, officials were able to quickly task employees with constant surveillance of high-traffic areas during the festival weekend.

NetMethods deployed a team to install the proposed wireless system in Savannah with less than two-weeks to go before St. Patrick's Day. When the team took a closer look at the planned camera locations, they realized that some installation points were no longer viable. For example, there were limited mounting assets and power supplies from what they originally anticipated; foliage in between camera points was much thicker than they thought; and nearby water threatened to change the way signals were received from node to node. However, because officials chose a wireless system affording greater flexibility, the team was able to find alternative options on the spot and the installation was able to proceed with minimal disruption to the original timeframe.

The wireless surveillance system designed for the City of Savannah was in place within one week. It was considered a great success and enabled local police, emergency personnel and public safety officials to provide increased security for the visitors and citizens celebrating in the historic city and its streets. Ultimately, the wireless mesh network provided an affordable solution that did not require large-scale cabling through old city streets; it provided a flexible and scalable solution that could be implemented and deployed within their time constraints; and it provided city officials the ability to access surveillance remotely and quickly.


Moving Forward With Wireless Surveillance

The St. Patrick's Day installation was initially developed as a quick, temporary solution to accommodate the surveillance of a large influx of people into a small city center under varying physical conditions. However, because officials chose a wireless mesh network, they had the option of expanding the surveillance project to accommodate their long-term needs. The scalability, combined with the success of the St. Patrick's Day installation, prompted city officials to deem the wireless surveillance operation a permanent part of the City's ongoing surveillance efforts. Since the city's most recent installation, officials have agreed to add even more cameras to the historic Riverwalk area as determined by public safety needs.

The City of Savannah will continue to use wireless networks in expanded phases throughout the city. Its long-term goals are to leverage the power of the network beyond traditional policing and into other environments including schools, community centers, and local ports. The ease of connectivity and scalability offered by Axis' network cameras with a mobile mesh network will allow the City of Savannah to become a more mobile government, allowing officials to easily adjust to the growing needs of citizens.


About the author: Fredrik Nilsson is general manager of Axis Communications, a provider of IP-based network video solutions that include network cameras and video servers for remote monitoring and security surveillance.