Talking In The Dark
The recent experience of Hurricane Katrina was an excruciating lesson in the utter dependence we have on our communications systems: The panic and chaos that followed the storm were exacerbated by the failure of our communications networks, as the only devices that still worked for the weeks after Katrina hit were satellite phones and two-way radios.
Wi-Fi mesh offers a self-correcting communication system capable of surviving a disaster of Katrina’s magnitude. Conventional phone systems are centrally operated, meaning that the disruption of a small cache of switches affects service for a large portion of users; also, they are frequently overwhelmed in times of disaster, as they are only designed to allow 10 percent of customers to talk at once.
Wi-Fi mesh systems are inexpensive and decentralized, and can easily support a phone system impervious to disaster. Meshed Wi-Fi can be thought of as a widescale bucket brigade, as each node transmits data to the next, located only a few hundred feet away; Wi-Fi also supports VoIP, and enables widespread connectivity to the Internet if just one user is logged on.
Mesh networks are ideal for disaster situations, as the removal of a given node does nothing to disrupt a widely implemented Wi-Fi network. They are also remarkably efficient and inexpensive, as each node only consumes about 10 watts, and carries an implementation cost of around $350, a figure that increases to $650 with the addition of an emergency battery.
Though Wi-Fi nodes do require a clear line of sight to communicate with each other, their marginal cost makes their widespread implementation in densely clustered urban areas eminently viable.
Abstracted by the National Law Enforcement and Corrections Technology Center(NLECTC) from the New York Times Magazine (09/18/05) P. 24; Thompson, Clive.