The new generation network that includes the wireless devices which are able to move freely or independently in random directions and speed with regulation of any authority and connected through the wireless links can be termed as ad-hoc networks. Fast expansion of wireless communication technology and the broad usage of mobile communication tools, wireless ad hoc networks are getting more and more consideration. Nowadays, wireless ad hoc networks are not only used in military, but also been applied to civilian application, including home area networks, mobile communication networks, and so on. With the widespread rapid development of computers and the wireless communication, the mobile computing has already become the field of computer communications in high-profile link. An Ad hoc network is a collection of mobile nodes, which forms a temporary network without the aid of centralized administration or standard support devices regularly available as conventional networks. These nodes generally have a limited transmission range and, so, each node seeks the assistance of its neighboring nodes in forwarding packets and hence the nodes in an Ad hoc network can act as both routers and hosts. Thus a node may forward packets between other nodes as well as run user applications. By nature these types of networks are suitable for situations where either no fixed infrastructure exists or deploying network is not possible. Ad hoc mobile networks have found many applications in various fields like military, emergency, conferencing and sensor networks. Each of these application areas has their specific requirements for routing protocols.
MANET is a collection of two or more devices or nodes or terminals with wireless communications and networking capability that communicate with each other without the aid of any centralized administrator also the wireless nodes that can dynamically form a network to exchange information without using any existing fixed network infrastructure. And it’s an autonomous system in which mobile hosts connected by wireless links are free to be dynamically and some time act as routers at the same time. All nodes in a wireless ad hoc network act as a router and host as well as the network topology is in dynamically, because the connectivity between the nodes may vary with time due to some of the node departures and new node arrivals. The special features of Mobile Ad Hoc Network (MANET) bring this technology great opportunity together with severe challenges
Wireless ad hoc networks are envisioned to be one of the most important parts of future Internet. However, in civilian wireless ad hoc networks, nodes often belong to different parties who have their own interests and always want to maximize their own benefits. Such selfish behavior can hurt the robustness and availability of wireless ad hoc networks. Here solution concepts from microeconomics and game theory to study important incentive problems in wireless ad hoc networks, including spectrum allocation and routing. Here objective is to achieve a series of cooperation-incentive mechanisms with high availability, low cost, and high adaptability, through the following four closely related studies: game-theoretic problem modeling, impossibility analyzing, strong incentive mechanism designing, and systematic evaluation methodology is developing.
Figure 1: Wireless Ad hoc Network
Mobile ad hoc network is a new technology. That is basically invented for those conditions where the management of huge infrastructure and maintenance is costly, such as battle ground. MANET (Mobile ad hoc network) is defined by its own characteristics; it is self-organizing, mobile communication manner where topologies are dynamically created. Due to the ad hoc nature of the network infrastructure and mobility it is still an area of new research and development. Due to mobility of wireless communication two major issues are found in such kind of network i.e. performance and security.
Challenges of Mobile Ad Hoc Networks
Ad hoc networking has been a popular field of study during the last few years. Almost every aspect of the network has been explored in one way or other at different level of problem. Yet, no ultimate resolution to any of the problems is found or, at least, agreed upon. On the contrary, more questions have arisen. The topics that need to be resolved are as follows:
- Quality of service
- Client server model shift
- Energy conservation
- Node cooperation
Issues to be Considered when Deploying MANET
The following are some of the main routing issues to be considered when deploying MANETs:
- Unpredictability of Environment
- Unreliability of Wireless Medium
- Resource-Constrained Node
- Dynamic Topology
- Transmission Errors
- Node Failures
- Link Failures
- Route Breakages
- Congested Nodes or Links
Features of Mobile Ad Hoc Networks
The mobile Ad hoc networks has the following features:
- Autonomous terminal
- Distributed Operation
- Multi-hop routing
- Dynamic network topology
- Fluctuating link capacity
- Light-weight terminals
Application of MANET
Some distinctive MANET applications include:
- Military field: Ad-Hoc networking can permit army to exploit benefit of conventional network expertise for preserving any info network among vehicles, armed forces, and headquarters of information.
- Cooperative work: To facilitate the commercial settings, necessity for concerted computing is very significant external to office atmosphere and surroundings as compared to inner environment. People want getting outside meetings for exchanging the information plus cooperating with each other regarding any assigned task.
- Confined level: Ad-Hoc networks are able to freely associate with immediate, in addition momentary hypermedia network by means of laptop computers for sharing the info with all the contestants’ e.g. classroom and conference. Additional valid and confined level application may be in domestic network where these devices can interconnect straight in exchanging the information.
- PAN and Bluetooth: A PAN is localized and tiny range network whose devices are generally belong to a specified individual. Limited-range MANET such as Bluetooth can make simpler the exchange among several portable devices like a laptop, and a cell phone.
- Business Sector: Ad-hoc network could be used for rescuing and emergency processes for adversity assistance struggles, for instance, in flood, fire or earthquake. Emergency saving procedures should take place where damaged and non-existing transmissions structure and quick preparation of a transmission network is required.
- Sensor Networks: managing home appliances with MANETs in both the case like nearby and distantly. Weather sensing related activities. Backup Services: liberation operations, tragedy recovery, diagnosis or status or record handing in hospitals, replacement of stationary infrastructure. Educational sector: arrangement of communications facilities for computer-generated conference rooms or classrooms or laboratories.
 Saleh Ali K.Al-Omari and Putra Sumari, “An overview of Mobile Ad hoc Networks”, for the existing protocols and applications, International Journal on Application of Graph theory in wireless ad-hoc networks, Volume 2, Number 1, March 2010
 Naeem Raza and Muhammad Umar Aftab, “Mobile Ad-Hoc Networks Applications and Its Cha’llenges”, Communications and Network, 2016, 8, pp. 131-136
 Vinit Garg and Manoj Kr.Shukla, “Advance Survey of Mobile Ad-Hoc Network”, IJCST Volume 2, Issue 4, Oct. – Dec. 2011
 “Chapter – 3: Overview of Mobile Ad Hoc Networks”, available online at: http://shodhganga.inflibnet.ac.in/bitstream/10603/4106/11/11_chapter%203.pdf