Mobile ad-hoc network
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A mobile ad-hoc network (MANET) is a self-configuring network of mobile routers (and associated hosts) connected by wireless links—the union of which form an arbitrary topology. The routers are free to move randomly and organise themselves arbitrarily; thus, the network's wireless topology may change rapidly and unpredictably. Such a network may operate in a standalone fashion, or may be connected to the larger Internet.
The earliest MANETs were called "packet radio" networks, and were sponsored by DARPA in the early 1970s. BBN and SRI designed, built, and experimented with these earliest systems. Experimenters included Jerry Burchfiel, Robert Kahn, and Ray Tomlinson of later TENEX, Internet and email fame. It is interesting 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 MANETs are designed primarly for military utility; examples include JTRS and NTDR.
The popular IEEE 802.11 ("Wi-Fi") wireless protocol incorporates an ad-hoc networking system when no wireless access points are present, although it would be considered a very low-grade ad-hoc protocol by specialists in the field. The IEEE 802.11 system only handles traffic within a local "cloud" of wireless devices. Each node transmits and receives data, but does not route anything between the network's systems. However, higher-level protocols can be used to aggregate various IEEE 802.11 ad-hoc networks into MANETs.
A list of some ad-hoc network protocols can be found in the Ad hoc protocol list.
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.
See also
External links
- IETF MANET group (http://www.ietf.org/html.charters/manet-charter.html)
- Mobile Mesh Networking Blog (http://mark.cabiling.free.fr/mobilemesh/)
- CityMesh.de Info-Site about Meshing and MAN (German language) (http://www.CityMesh.de)
- Mobile Java based Mesh networking development at AirHive Net (http://www.airhive.net/)
- MIT Media Lab laptop program (http://laptop.media.mit.edu/)
References
Packet Radio Papers
- J. Burchfiel, R. Tomlinson, M. Beeler, "Functions and structure of a packet radio station", AFIPS 1975, p. 245.
- Kahn, R. E., "The Organization of Computer Resources into a Packet Radio Network," IEEE Transactions on Communications, Vol. COM-25, No. 1, pp. 169-178 (January 1977).
- Kahn, R. E., Gronemeyer, S. A., Burchfiel, J., Kunzelman, R. C., (1973) "Advances in Packet Radio Technology", Proceedings of IEEE. vol. (11):1468--1496, November 1978.
- Jubin, J., and Tornow, J. D., "The DARPA Packet Radio Network Protocols", Proceedings of the IEEE, vol 75, no 1, January 1987.
- N. Schacham and J. Westcott, "Future directions in packet radio architectures and protocols", Proceedings of the IEEE, 75(1):83-99, Jan 1987.