Troops on the move need to stay connected and that requires mobile communication. On the surface, this doesn’t seem like much of a demand considering how mobile communication and connectivity dominates so much of our modern civilian world.
Military standards are quite different, and it’s not just because milcom headsets are so much more specialized than your average cell phone. Tactical communications need to be far more secure and stable, even in some of the most inhospitable conditions. You can’t have any unauthorized parties listening in or any vulnerabilities that would cause a loss of connection at a critical time. Even the most reliable telecom and internet carrier cannot always ensure that.
One of the main problems with using conventional mobile for military applications is the reliance on hubs. These hubs can easily be destroyed, thus dismantling the network they connect. Peer-to-peer systems instead rely on nodes to complete the connection, as well as a series of hops based in the devices that rely on the network. These systems are more often static than mobile and requires advanced individual set up of each node. Constant reconfiguration is also needed to allow for mobility, which makes it a less than ideal solution in many situations.
A better system has been proposed but was until recently beyond the limits of current network design capabilities. MANET, a mobile ad-hoc network, works through a series of routing tables that track the shortest connections across all nodes. This tracking requires constant and increasing processing power for each additional node in the network. Constant messages must be sent to each node, which then crowds out all other traffic.
A few years ago, DARPA put out the call for plans that would allow for a MANET consisting of more than 50 nodes capable of supporting voice, text, and data. Just this year, a proposed system was tested that allowed for 320 nodes supporting all those capabilities at 30m bits per second. Each node was contained in a handheld unit that resembled an oversized smartphone.
By overcoming the routing-table and constant messaging problem, this MANET system was able to connect reliably, using a route “remembering” trick that bypassed the short routing from node to node. The network was further streamlined through a technique known as “overhearing”, which enables one node to pick up on connections to establish shorter paths than those planned.
In addition to serving the mobile communication needs of the military, this system could be used by search and rescue and emergency response workers to stay connected when other communication resources are unavailable.