Saturday, October 10, 2015

History of Ad Hoc Network

The earliest wireless ad-hoc networks were called "packet radio" networks, and were sponsored by Defense Advanced Research Projects Agency (DARPA) in the early 1970s. Bolt, Beranek and Newman Technologies (BBN) and SRI International designed, built, and experimented with these earliest systems. Experimenters included Jerry Burchfield, Robert Kahn, and Ray Tomlinson of later TEN-EXtended (TENEX), Internet and email fame. Similar experiments took place in the Ham radio community.

 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 wireless ad-hoc networks are designed primarily for military utility


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Friday, October 9, 2015

What is Ad Hoc Network

Ad-hoc network

Ad-hoc is a Local Area Network that is built spontaneously and doesn’t rely on pre-existing infrastructure such as routers, etc.

Hence, all devices in an ad hoc network have equal status on a network and participate in  routing and data-forwarding. Data packets are dynamically forwarded to and from each other. It’s useful in areas where central nodes don’t exist or can’t be relied upon. This is widely used in emergency situations and  military conflicts.

Ad hoc networks can be easily and quickly deployed  which increases its application domain.

Two types of ad-hoc networks are possible depending upon the devices that are connected:

Heterogeneous, where each machine has different capabilities and hence performs different actions and Homogeneous, where all machines/nodes  have the same capabilities and hence the same responsibility.

Three types of ad-hoc networks exist on the basis of its application:

1. Mobile Ad-Hoc networks: A network of mobile devices.

2. Wireless Mesh networks: A network of radio nodes in a mesh topology.

3. Wireless Sensor networks: A network of distributed  autonomous sensors to monitor physical or environmental conditions.



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