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CASE STUDY - COW To The Rescue
by Mark Gilbaugh, Keith Lewis, and Tac Berry

Fighting fires in California is a nasty business; add in the additional problems of remote locations, non-existent cellular communication channels, and coordination of multiple fire companies, and the business gets worse. In July, 2008, a large fire in Northern California near Big Sur (Basin Complex fire) required the call-out of 3,000+ firefighters from more than 50 crews, almost 100 engines, and more than 20 aircraft. The initial area of the fire was the beautiful but remote Los Padres National Forest and Park, south of Monterey (Ventana wilderness area).

For vacationers, this area has traditionally been one of the most beautiful drives along the Pacific coast. But due to the terrain and remote areas, mobile phone service in this area is sketchy at best and often non-existent. An annoyance is not being able to call home while touring the California coast — the annoyance turns into total frustration when supporting thousands of firefighters and there is no cell service to aid critical communications.

To solve this problem, several companies worked together to quickly install a communication system known as a ‘COW’. COW stands for Cellular on Wheels, an industry description for a transportable mobile communications access point. The COW is a system designed to provide mobile services for short periods of time during potential high cell traffic periods (Cell On Wheels - Wikipedia) Think of communities holding major events, such as the Super Bowl, that require additional mobile connections, but just for a few days. During such situations, the unusually high volume of mobile calls can often overwhelm a standard cellular network. Adding temporary cellular switching capacity has become a standard practice by all mobile service providers to help alleviate the call volume problems and assure mobile phone access for all callers.

Normally the COW can be rolled into a parking lot, powered up, and then connected to local switching equipment using standard Telco T1 interfaces (wired or wireless). The system then performs like a reserve switching point for the overload of mobile voice and data traffic. As was shown during the Big Sur fires, a COW can also be used in emergencies to extend cellular services to remote areas with the right combination of technology and expertise.

In the case of the Big Sur fire, of course, there were no local switching points for a COW interface. There were not even T1 connections within reasonable reach of the equipment installation site. The COW, by itself, does not solve any cellular access problems without a connection to the main telephone switching network.
Additionally, the complexity and technical requirements for installation increases significantly when a COW is required for communications outside the reach of typical Telco interfaces. But, making cell service available for the fire fighters was a necessity — a solution had to be implemented.

With the remote locations of the Basin Complex fire, the COW access to the PSTN (Public Switched Telephone Network) was to be more than 50 miles away from the actual COW equipment. The U.S. Forest Service contacted ComCentric and asked for their assistance in the installation of cellular access equipment for the firefighters that could be remotely connected using satellite data circuits.

Satellite communications has becoming significantly more available and more economical with the addition of IP, packet-based circuits. Using packet protocols mean that a satellite link does not have to be dedicated to a single broadband user, like a T1 connection must be. The bandwidth per satellite can be shared by more users and each user gets the bandwidth they require when they have data to transmit. If the connection to one user is idle, the bandwidth is available for another user’s IP packets. This ‘sharing’ of the satellite bandwidth means lower costs and more connections being completed.

To use a packet-based satellite backhaul path, the COW interfaces would have to be converted to IP packets to support the satellite protocol standards. Satellite networks and IP backhaul over satellite is ComCentric’s expertise. The company is a Washington-based reseller and system integrator specializing in highly secure, mobile communication solutions. Their experience is derived from years of designing secure networks to provide remote connectivity and highly reliable services for local and Federal government requirements. Experience with using satellite communication connections for network backhaul meant the company offered significant expertise when engineering the system infrastructure and technical specifications.

ComCentric had to determine the technical requirements for engineering a satellite communications link for backhaul from the remote COW equipment to the switching network point of presence (POP). To make the network connection in this remote environment, ComCentric contacted ATCONTACT COMMUNICATIONS, a leading Ku- / C- and Ka-band satellite services provider. ComCentric worked with ATCONTACT to provide custom network technical services and satellite capacity extending access to the Cell On Wheels even in the remote environment.

With a satellite link now being engineered, ComCentric needed to convert the existing telecom T1 interfaces, standard with the COW equipment, to a packet-based interface for the AtContact satellite backhaul. This is where Engage Communication became involved in the project. Engage provides a series of high-speed TDM to IP conversion products specifically designed for backhaul of legacy telecom circuits over packet-based networks. Engage has had significant experience in using packet technologies for traditional telecommunication connections, such as IP over Satellite, as well as in designing solutions for connectivity to COWs.

The key when adapting a packet network for communication services is to maintain proper interface timing and communication standards. This is even more important when converting cell voice and data traffic to IP and then transmitting these packets over satellite links. Satellite communication has inherent latency in delivery of traffic due to the time delay of satellite interfaces. The conversion equipment must be able to handle these inherent delays and maintain proper network timing.

ComCentric and Engage designed an interface using the latter’s products that were available in a short timeframe as well as reliable and robust enough to handle the satellite links as part of the network. Engage provided their IP-Tube, T1 to IP converter. The IP-Tube encapsulates full and fractional T1 circuits into IP packets. This enables legacy telephone circuits to be carried over high-speed packet network connections. The product maintains all required signaling interfaces and protocols for telephone network control and allows standard telephone test patterns to be used for end-to-end circuit testing and maintenance.

The communication from the COW became packet based and was carried over satellite from the fire locations to the receiving station at the ATCONTACT facility. The call traffic had to be carried from the receiving location to the public switching network. This demonstrated another benefit of using packet protocols for the connections.

By using ATCONTACT’s VSAT IP Network, traffic from the receiving station site could still be transported as IP packets on the final leg to the public switching network. Using legacy Telco type of transmission interfaces would have required multiple protocol conversions and could have delayed the project due to T1 availability issues on the terrestrial side of the installation. Instead the packet-based data protocols made it possible to use the existing broadband services for the final terrestrial leg of the network.

ATCONTACT’s advanced Internet backbone network transported the packet-based traffic (encrypted) from the receiving Earth station to the public network access point, providing an end-to-end IP Network, with only 11 hops from satellite to switch. Engage IP conversion products were again installed at the termination of the final transmission leg to change the packet information back to TDM voice circuits. The voice traffic was then available to the public switching network.

The final technical solution was capable of handling thousands of mobile phone calls in even the remotest areas of the Big Sur Wilderness. The crews fighting the fires in those remote locations definitely appreciated the equipment, which permitted personal and official communications over previously unavailable cellular networks. The fire resulted in more than 162,000 acres of wilderness area destroyed. The cost to fight the fire, protect structures, and finally contain the fire, was more than US$77 million.

High technology can provide solutions to problems caused by the most primitive of situations and locations. The correct blend of technical expertise, desire to solve problems, and reliable equipment can be combined to meet even the most critical of emergencies.

ComCentric, designs and installs emergency satellite internet and phone service to the U.S. Forest Service. ComCentric is a veteran owned small business located near Olympia, Washington specializing in emergency wireless and satellite communications. More information at http://www.comcentricusa.com.

Engage Communication manufactures transmission interface products that enable existing voice circuits and PBX connections to be converted to Ethernet or IP for backhaul and automatic path switchover. Engage products can provide compression of voice information and encryption of voice, serial and IP circuits to meet AES standards and can network SS7 data messages for billing and call management. Engage IP products are SNMP manageable and provide SSH security for in-band control and configuration. More information: http://www.engageinc.com.

ATCONTACT provides comprehensive broadcast, streaming and data services using satellite technologies from its secure satellite earth station in Colorado. ATCONTACT provides affordable VSAT IP services through its iDirect VSAT hub to rural locations in the Lower 48, Alaska, Central and South America including the Caribbean. ATCONTACT is a leading provider of custom Satellite communication solutions and networks for Telcos / Government / Oil and Gas, Mining and Business sectors. For more information, please visit http://www.atcontact.com.

About the authors
Mark Gilbaugh is the President of ComCentric and, prior to establishing the Company, he served in the U.S. ARMY as a Med-Evac Instructor Pilot. During his tenure, Mark deployed twice to Iraq and has held the positions of Med-Evac Team Leader, Information Management Officer, and Military Assistance to Safety and Traffic (MAST) Frequency Coordinator. Prior to joining the U.S. Army, he had been a lead technician for a telecommunications provider installing systems for state and federal government agencies, including the Tennessee Highway Patrol’s E-911 system. Mark is a BICSI certified technician, and has over 12 years of experience in the telecommunications industry.

Keith Lewis is in the Business Development division with ATCONTACT. Before to joining the Company 10 years ago, Keith spent 5 years in Bahrain, consulting for telephone and data companies in the adoption of secure smart card based technologies for ecommerce, streaming media for live and on demand applications, multimedia, and audio advertising production for clients such as Coca Cola, KLM Airlines, Quantus, Batelco, Brtish Airways and Starbucks. Keith joined ATCONTCACT as IT Manager and built the entire IP and streaming architecture for the Teleport. He broadened his knowledge in to VSAT and Satellite communications with network design, operation, and maintenance of all platforms.

Tac Berry (with Luke) is the Vice President of Business Development at Engage Communication. He has worked in the telecommunications industry for more than 30 years. After 6 years as a MTS with Bell Laboratories, he held Marketing and Business Development positions for companies that include Granger Associates, Digital Link, Amati Communications, and Jetstream.