Wireless Mesh Networks
Wireless Mesh Networks,
explained by the Wikipedia at http://en.wikipedia.org/wiki/Wireless_mesh_network
Wireless mesh networking is mesh networking implemented over a Wireless LAN.
"This type of Internet infrastructure is decentralized, relatively inexpensive, and very reliable and resilient, as each node need only transmit as far as the next node. Nodes act as repeaters to transmit data from nearby nodes to peers that are too far away to reach, resulting in a network that can span large distances, especially over rough or difficult terrain. Mesh networks are also extremely reliable, as each node is connected to several other nodes. If one node drops out of the network, due to hardware failure or any other reason, its neighbours simply find another route. Extra capacity can be installed by simply adding more nodes. Mesh networks may involve either fixed or mobile devices. The solutions are as diverse as communications in difficult environments such as emergency situations, tunnels and oil rigs to battlefield surveillance and high speed mobile video applications on board public transport or real time racing car telemetry. The best mobile networks are those that provide a seamless handover between the mobile device and the fixed infrastructure points." (http://en.wikipedia.org/wiki/Wireless_mesh_network)
"In basic terms,the mesh provides an alternative to established methods of linking computers together and connecting them to the internet. In practice,it can be used to build large networks far more quickly and cheaply than has previously been possible.As a result,wireless networks are viable in unexpected places. New Orleans,still without a phone service after Hurricane Katrina, recently began building a free,citywide network using mesh technology,while the whole of Macedonia is now one big wireless hotspot. Networks are also providing web connections to people in the parts of the UK untouched by phone-based broadband,as well as in developing countries that have never had effective telephone networks". (from Times Online, quoted by http://www.smartmobs.com/archive/2006/01/28/wireless_mesh_n.html)