Wireless ad-hoc network

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A wireless ad-hoc network is a computer network in which the communication links are wireless. The network is ad-hoc because each node is willing to forward data for other nodes, and so the determination of which nodes forward data is made dynamically based on the network connectivity. This is in contrast to older network technologies in which some designated nodes, usually with custom hardware and variously known as routers, switches, hubs, and firewalls, perform the task of forwarding the data. Minimal configuration and quick deployment make ad hoc networks suitable for emergency situations like natural or human-induced disasters, military conflicts, emergency medical situations etc.

The earliest wireless ad-hoc networks were called "packet radio" networks, and were sponsored by DARPA in the early 1970s. BBN Technologies and SRI International designed, built, and experimented with these earliest systems. Experimenters included Jerry Burchfiel, Robert Kahn, and Ray Tomlinson of later TENEX, Internet and email fame. Similar experiments took place in the Ham radio community. It is significant to note that these early packet radio systems predated the Internet, and indeed were part of the motivation of the original Internet Protocol suite. Later DARPA experiments included the Survivable Radio Network (SURAN) project, which took place in the 1980s. Another third wave of academic activity started in the mid 1990s with the advent of inexpensive 802.11 radio cards for personal computers. Current wireless ad-hoc networks are designed primarily for military utility; examples include JTRS and NTDR.

A list of some ad-hoc network protocols can be found in the Ad hoc routing protocol list. Types of wireless ad-hoc networks include Mobile ad-hoc networks (MANets), Wireless Sensor Networks, and Wireless Mesh Networks.

The MIT Media Lab $100 laptop program hopes to develop a cheap laptop for mass distribution (>1 million at a time) to developing countries for education. The laptops will use ad-hoc wireless mesh networking to develop their own communications network out of the box.

[edit] References

Packet Radio Papers:

Burchfiel, J., Tomlinson, R., Beeler, M. (1975). "Functions and structure of a packet radio station". AFIPS: 245.
Kahn, R. E. (January 1977). "The Organization of Computer Resources into a Packet Radio Network". IEEE Transactions on Communications COM-25 (1): 169–178.
Kahn, R. E., Gronemeyer, S. A., Burchfiel, J., Kunzelman, R. C. (November 1978). "Advances in Packet Radio Technology". Proceedings of IEEE 66 (11): 1468–1496.
Jubin, J., and Tornow, J. D. (January 1987). "The DARPA Packet Radio Network Protocols". Proceedings of the IEEE 75 (1).
N. Schacham and J. Westcott (January 1987). "Future directions in packet radio architectures and protocols". Proceedings of the IEEE 75 (1): 83–99.