Saturday, October 1, 2005

Supporting combat operations using mobile ad-hoc networks


By Humayun Bakht

The history of the mobile ad-hoc networks goes back to the early 1970s, when they were first used in DARPA (Defense Advanced Research Projects Agency). Handheld multimedia terminals were designed to establish a tactical Internet and were used to allow each wireless terminal to function as an independent, intelligent, router and repeater. Another important aspect of these terminals was their support for the simultaneous operations of VoIP (Voice over IP), data, and multimedia at a higher data rate in the battlefield environment where no infrastructure was available.

Ad-hoc networking offers a self-organizing and multi-hop network structure. Each routing terminal acts as a router that forwards data packets to all the other nodes in the network, thereby extending the range and the coverage of communications links among the soldiers, troop transports, and control centers.

Some of the essential requirements of a combat operation include network deployment, network security, end-to-end IP, high mobile connectivity, and anti-jamming mechanisms. In most cases, military operations are often set up with little or no fixed network infrastructure. These operations require a communications solution where the soldiers can form a network when and where it's needed. The network should also be able to set up automatically when the troops leave a transport, helicopter, or ship.

In a combat operation, it's essential to be able to locate the troops. Mobile ad-hoc networks can support the built-in geographical location by using an extremely accurate form of triangulation. This feature enables soldiers in a military operation to triangulate its position based on the mobile enabled vehicles or other devices. In mobile ad-hoc networks, readings are faster than GPS (global positioning systems) because the soldiers don't have to wait for multiple satellites to acquire a centralized security.

The devices used in combat operations must be able to address both communications security and a way to secure the network from unauthorized use. Communications can be more secure when mobile ad-hoc networks allow for route diversity. Mobile ad-hoc networks also allow devices to transmit at a lower output power to other devices in the network, which benefits the overall network by lowering the probability of detection and by increasing the battery life of the participating devices.

Through anti-jamming mechanisms, the soldiers in a military operation are neither dependent on a single frequency nor are they constrained to any military band. Mobile ad-hoc networks are best suited to jamming because noise can now be routed around problem areas. These self-forming areas will have the ability to reduce the probability of jamming.