Gugrajah_Yuvaan_ Ramesh_2003.pdf

Introduction Chapter 1
There are a variety of application areas for ad hoc networks. Search and rescue
missions in areas where existing infrastructure has been destroyed or is non-existent.
can benefit from these decentralized networks. Ad hoc networks could· also be an
advantage for data acquisition in inhospitable or unexplored terrain. Networks of
wireless devices for voice and video communication, digital maps, and mobile
sensors can provide valuable tactical information in military applications. The history
of ad hoc networks can in fact be traced back to 1972 [Ram02] when the US
Department of Defence introduced the Packet Radio Network (PRNet), which later
became the Survivable Adaptive Radio Networks (SURAN) program. The Near­
Term Digital Radio (NTDR) [Cotter02] is the latest incarnation of the US military's
mobile packet radio networks and is the only non-prototype ad hoc network in use
today.
The Institute of Electrical and Electronic Engineers (IEEE) replaced the designation
"packet radio network" with "ad hoc network" when developing the 802.11 standard'
for Wireless Local Area Networks (WLAN) in the hope that it would indicate a new
deployment scenario different from the associated multihop networks of large scale
military operations. Commercial applications, where individual users need to share
or exchange information without depending on a local network of access points, can
employ ad hoc networks for collaborative wireless networking. Ad hoc networks can
play a role in civilian forums such as classrooms, convention centJ;"es and office
blocks. Quick deployment and configuration can be used in rural areas where cellular
networks are unavailable. Personal Area Networks (PANs), which are small scale ad
hoc networks, allow intercommunication between a person's various mobile devices,
eliminating the need for cables and could also be used to extend the mobility
provided by the fixed network.
Two of the technologies that are currently competing for commercial applications are
the Bluetooth standard [Haartsen98], [Bluetooth] and the IEEE 802.11 standard
[IEEE99].
Bluetooth is a universal radio interface that uses a frequency-hopping spread
spectrum scheme in the unlicensed 2.4 GHz frequency band. Portable electronic
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