an intermediate router or routers are needed to help in forwarding the data among nodes. In
the absence of infrastructure in the ad hoc network, the router will be one of the nodes in the
network, thus every node in the network will act as host and as router. As a router, the node
should be able to forward data and run routing protocol. At the same time the node acts as a
host with an IP address in a traditional sense.
The wireless ad hoc nodes are often mobile. Two nodes at any time may be within each other
range, however due to their mobility the two nodes might be outside its counterpart range.
Change in topology related to node mobility may break the links between nodes and
therefore other links should be established. The paths between two nodes may consist of
many links passing over several nodes in the middle: a case that is called “multihop routing”.
2.3 Features and Applications of Wireless Ad Hoc Network
Wireless ad hoc networks are suitable for applications where there is a lack of infrastructure
or establishment of an infrastructural network is cost effective. Examples of wireless ad hoc
networks applications: Military operations, search and rescue operations, Bluetooth,
conference room and Personal Area Networks (PAN). The purpose of this section is to
highlight these examples.
2.3.1 Military operations
These kinds of operations are considered the primary application for ad hoc networks. The
military operations require high survivability, reliability and fast communication recovery,
but in an environment that does not possess infrastructure. Ad hoc network is the best
solution for this application considering these essential features.
2.3.2 Search and rescue operation
Ad hoc network is very beneficial when the infrastructure is damaged because of natural
disasters. Medical and other supporting teams working on disaster recovery need fast and
effective communications where they do not have time to wait establishment wired network
to start working in the area of disaster, and the nature of work during the disaster recovery
requires a flexible communication network. Ad hoc network can establish communication
network among disaster recovery teams very quickly and with flexible network topology.
11