Comparative Study of Routing Protocols in MANET

Routing protocol is the essential and vital performance factor in the Mobile Ad-hoc Network. The routing protocols in MANET are accomplished to handle a lot number of nodes with restricted resources. There is a variety of routing protocol exist in MANET. The routing protocol which is chosen may have an effect on the performance of network. In this paper, We perform a comparative study of DSDV, CSGR, WRP, AODV, OLSR, DSR, TORA, ZRP, ZHLS, DYMO routing protocol with respect to Routing Approaches, Routing structure, Route selection, Route, Routing table, Route maintenance, Operation of protocols, Strength, Weakness.


INTROdUCTION
MANET (Mobile Ad hoc Network) is collection ofmobile nodes which having the Autonomous Self -configuring network.In MANET, the nodes can flow freely and at any time it can connect to different nodes.Mobile nodes having the bandwidth restricted, dynamic topologies, Energy limited operation, variable infrastructure & capacity links.Routing protocol performs an essential function in any network 1 .Routing protocol specifies the routes between the nodes and disseminating information which choose the routes between any two nodes on a network.The rest of the paper is organized as follows.The classifications of routing protocol in MANET are explained in section II.Further the comparisons of routing protocols DSDV, DSR, AODV & OLSR are explained in Section III.Concluding remarks are given in section IV.

Classification of Routing Protocol
There are different routing protocols existing in MANET.Routing protocols can be classified into three types:Proactive, Reactive routing protocol and Hybrid protocols.The routing protocols in MANET are accomplished to handle a lot number of nodes with restricted LALAR & YADAV, Orient.J. Comp.Sci.& Technol.,Vol.10(1), 174-179 (2017)   resources.The major concern in routing protocol is disappearing/ appearing of the nodes in various places.It is important to reduce routing message overhead despite the growing number of mobile nodes.Another important concern is to maintain the size of routing table small because if the size of routing protocol is larger than it can affect the control packet transferred inside the network.
Routing protocol is categorized on the idea of how and at what time route are discovered, however both pick the shor test path to the destination.

Proactive Routing Protocols
This type of routing protocols uses link-state routing algorithms which floods link information about its neighbours frequently.Proactive routing protocol stores the routing information and maintains the information up to date by exchanging the control packet from their neighbours.The examples of proactive routing protocols are DSDV, OLSR, and WRP etc 8 .

Reactive Routing Protocols
Reactive routing protocols reduce overheads that are present in proactive protocols.It uses distance-vector routing algorithm and establishes the route to given destination only when a node request it by initiating route discovery process.There are number of reactive routing protocols available in MANET 4 like DSR, AODV, TORA and LMR etc.

Hybrid Routing Protocols
It is the mixture of reactive and proactive routing protocols.The example of Hybrid routing protocols are ZRP, BGP, EIGRP.Table 1 show the difference between the Proactive, Reactive routing protocol and Hybrid protocols in different features.
The figure 1 shows the example of the type of routing protocol.

CONCLUSION
This paper presents a comparative study of routing protocols in mobile ad-hoc networks.
These protocols are divided into three: proactive or table-driven, reactive or on-demand, and Hybrid routing protocols.For each of these classes, we have reviewed several representative protocols.Each routing protocol has unique features.The main factor that distinguishes the protocols is the method of determining routes within source destination pairs.The routing protocol DSDV, CSGR, WRP, AODV, OLSR, DSR, TORA, ZRP, ZHLS, DYMO is compared with respect to Protocol type, Routing Approaches, Routing structure, Route selection, Route, Routing table, Route maintenance, Operation of protocols, Advantages, Limitation.