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 wired 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. It is also in contrast to managed wireless networks, in which a special node known as an access point manages communication among other nodes. Minimal configuration and quick deployment make ad hoc networks suitable for emergency situations like natural disasters or military conflicts. The decentralized nature of most wireless ad hoc networks makes them suitable for a variety of applications where central nodes cannot be relied on, and may improve the scalability of wireless ad-hoc networks compared to wireless managed networks, though theoretical[1] and practical [2] limits to the overall capacity of such networks have been identified. Types of wireless ad-hoc networks include Mobile ad hoc networks (MANets), wireless mesh networks, and wireless sensor networks. In most wireless ad-hoc networks the nodes compete to access the shared wireless medium (the "ether"), often resulting in collisions. Using Cooperative wireless communications improves immunity to interference by having the destination node combine self-interference and other-node interference to improve decoding of the desired signal. The earliest wireless ad hoc networks were called "packet radio" networks, and were sponsored by DARPA.
References
- ^ P. Gupta and P.R. Kumar. Capacity of wireless networks. IEEE Transactions on Information Theory, Volume 46, Issue 2, March 2000, Digital Object Identifier 10.1109/18.825799 [1]
- ^ Jinyang Li, Charles Blake, Douglas S. J. De Couto, Hu Imm Lee, and Robert Morris, Capacity of Ad Hoc Wireless Networks, in the proceedings of the 7th ACM International Conference on Mobile Computing and Networking, Rome, Italy, July 2001 [2]
