International Journal of Engineering & Science Research - IJESR

IJESR/May 2013/ Vol-3/Issue-5/198-204

e-ISSN 2277-2685, p-ISSN 2320-9763

International Journal of Engineering & Science Research

EFFECTS OF ROUTING PROTOCOLS ON MOBILE AD- HOC NETWORKS Priyanshu Arya*1, Dr. Sandeep Vijay2, Isam Pal Chandra3 1

M.Tech Scholar, ECE Department, GRD Institute, Dehradun (UTU), India. 2

Prof. & HOD, ECE Department, DIT Institute, Dehradun, India.

3

M.Tech Scholar, ECE Department, GRD & IMT , Dehradun (UTU), India.

ABSTRACT A mobile ad-hoc network (MANET) is an autonomous system having the collection of mobile platforms or nodes where each node can move freely and arbitrarily without the benefit of any fixed infrastructure except for the nodes themselves. The performance of MANET is related to the efficiency of the routing protocols in adapting to frequently changing network topology and link status. Routing is one of the challenging issues in mobile ad-hoc network and plays a very important role in ad-hoc network. The contribution of this paper is to study the classification of various routing protocols also with its designing issues and various characteristics. This paper also helps in choosing the routing protocols according to desired application by understanding the advantages and disadvantages of each every protocol used in adhoc network. This in turn helps in the analysis the performance of various routing protocols over different parameters like overhead, average jitter, throughput etc

Keywords: Ad-hoc network, Routing protocols, Reactive Protocol, Proactive Protocol, Hybrid Protocols. 1. INTRODUCTION A mobile AD-HOC Networks (MANET) is basically a collection of various mobile nodes forming self configuring networks with various wireless links leading to an arbitrary topology. Because of less configuration and absence of any governing central authenticated body, makes an AD-HOC Networks suitable for emergency situation like natural disaster (earthquakes, flood etc), military battlefields, emergency medical situations etc. Most of the research in AD-HOC networks is simulation based which include various parameters including various Routing Protocols, Mobility Models & Communicating Traffic Patterns. Movement of data with the help of various routes between mobile nodes is based on various Proactive, reactive and hybrid routing protocols. The performance of any AD-HOC Network depends on the routing protocols used by it [1]. Examples of Various AD-HOC Networks are:

a) Mobile Devices

b) Vehicular network on Highway

c) Hybrid urban ad hoc network

Fig 1: Examples of Various AD-HOC Networks

2. ISSUES IN DESIGING A ROUTING PROTOCOLS IN AD-HOC NETWORKS There are various challenges faced by AD-HOC network in designing of routing protocols and they can be categorized as [3]: 2.1 Mobility Of Nodes: The network topology in an AD-HOC network is highly dynamic due to the movement of nodes. Hence an ongoing session suffers frequent path breaks. Thus routing protocols for AD-HOC networks must be able to perform efficient and effective mobility management.

*Corresponding Author

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2.2 Bandwidth Constraint: There is limited in wireless network which requires that the routing protocols use the bandwidth optimally by keeping the overhead as low as possible. 2.3 Error-Prone Shared Broadcast Radio Channel: It poses unique challenges in AD-HOC wireless networks. The wireless links have time varying characteristics in terms of link capacity and link-error probability. This requires that the AD-HOC network routing protocols interact with the MAC layer to find alternate routes through better quality links. It is also required that AD-HOC network routing protocols to find path with less congestion.

2.4 Hidden And Exposed Terminal Problem: The hidden problem refers to collision of packets at receiving nodes due to the simultaneous transmission of those nodes that are not within the direct transmission range of the sender, but are within the transmission range of the receiver. Thus routing protocols must be efficient to overcome such problem. 2.5 Resource Constraints: Two essential and limited resources that form the major constraint for the nodes in ADHOC network are battery life and processing power. Devices used in AD-HOC networks in most cases require probability, and hence they also have size and weight constraints along with the restrictions on the power source. Thus routing protocols must optimally manage these resources.

3. CHARECTERISTICS OF IDEAL ROUTING PROTOCOLS FOR AD-HOC WIRELESS NETWORK It must be fully distributed, as centralized routing involves high control overhead and hence is not scalable. It must be adaptive to frequent topology changes caused by the mobility of nodes. Routes consumption and maintenance must involve a minimum number of nodes. Each node must have quick access to routes. It must be localized, as global state maintenance involves a huge state propagation control overhead. It must be loop-free and free from stale routes. The number of packet collision must be kept to minimum by limiting the number of broadcast made by each node. It must converge to optimal routes once the network topology becomes stable and coverage must be quick enough. It must optimally use scarce resources such as bandwidth, computing power, memory and battery power. Every node in the network should try to store information regarding the stable local topology It should be able to provide a certain level of quality of services (QoS) as demanded by the applications, and should also offer support for time-sensitive traffic.

4. CLASSIFICATION OF ROUTING PROTOCOLS The deviation from the traditional routing metrics and path-finding process that are employed in wired networks makes it worth further exploration in this direction. The routing protocols for AD-HOC networks can be broadly classified into four categories based as[7]:

Routing information update mechanism Use of temporal information for routing Routing topology Utilization of specific resources.

A classification tree can be studied from figure given below:

Copyright © 2013 Published by IJESR. All rights reserved

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ROUTING PROTOCOLS FOR AD-HOC NETWORKS

Based On Routing Information Update Mechanism

Table Driven (Proactive)

On-Demand (Reactive)

Based on the use of Temporal Information for Routing

Based on Topology Information Organization

Path Selection Using Past History

Path Selection Using Prediction

Flat Routing

Hierarchical Routing

Hybrid

Based on Utilization of Specific Resources

Power-Aware Routing Routing Using Geographical Information

Routing With Efficient Flooding

Fig 2: Classifications of Routing Protocols

4.1 Based on the Routing Information Update Mechanism: Proactive or Table Driven Routing Protocols: Here every node maintains the network topology information in the form of routing tables by periodically exchanging routing information. Whenever a node requires a path to a destination, it runs an appropriate path-finding algorithm on topology information it maintain. Reactive or On-Demand Routing Protocols: These types of protocols do not maintain the network topology information. They obtain the necessary path when it is required, by using a connection establishment process protocols do not exchange routing information periodically. Hybrid Routing Protocols: They combine the best features of the above two categories. Nodes within a certain distance from the node concerned, or within a particular geographical region, are said to be within the routing zone of the given nodes. For routing within this zone, a table-driven approach is used. For nodes that are beyond this zone, an ondemand approach is used.

4.2 Based on the use of temporal information for routing Routing protocols using past temporal information: These routing protocols use information about the past status of the links or the status of links at at the time of routing to make routing decisions. Routing protocols that use future temporal information: They use information about the expected future status of the wireless links to make approximate routing decisions also include information regarding the lifetime of the nodes. Prediction of location and prediction of link availability.

4.3 Based on The Routing Topology Flat topology routing protocols: They make use of a flat addressing scheme similar to the one used in IEEE 802.3 LANs .It assumes the presence of a globally unique addressing mechanism for nodes in an AD-HOC wireless network. Hierarchical Topology Routing Protocols: They make use of a logical hierarchy in the network and an associated addressing scheme. The hierarchy could be based on geographical information or it could be based on hop distance.

4.4 Based on The Utilization of Specific Resources Power Aware Routing: It aims at minimizing the consumption of a very important resource in the AD-HOC Wireless networks. The routing decisions are based on minimizing the power consumption either locally or globally in the network. Geographical Information Assisted Routing: Here the protocols improve the performance of routing and reduce the control overhead by effectively utilizing the geographical information available.


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5. ADVANTAGES & DISADVANTAGES OF VARIOUS ROUTING PROTOCOLS 5.1 DSDV Advantages Much less delay is involved in the route setup process. It maintains an up-to-date view of the network topology at all the nodes.

Disadvantages This type of protocols suffers from excessive control overhead the is proportional to the number of nodes in the network. It is not scalable in AD-HOC networks. A node has to wait for a table update message; hence this kind of delay could leads in stale routing information at nodes [8].

5.2 WRP (Wireless Routing Protocols) Advantages It has faster convergence and involves fewer table updates. Here also less delay is involved in the route process.

Disadvantages • There is complexity in the maintenance of multiple tables. • It demands a larger memory and greater processing power. • It is not suitable for highly dynamic networks.

5.3 CGSR (Cluster - Head Gateway Switch Routing Protocol) Advantages

It enables partial coordination between nodes by electing cluster – heads. Here better bandwidth utilization is possible. It is easy to implement. It involves priority scheduling schemes with token facility and gateway code scheduling.

Disadvantages

There is increase in path length and instability in the system at high mobility. The rate of change of cluster head is high which leads in multiple path breaks . It requires more resources. The battery – draining rate at the cluster – head is higher.

5.4 DSR (Dynamic Source Routing Protocols)[6] Advantages It basically eliminates the need to periodically flood the network. It utililize the route cache information efficiently to reduce the control overhead.

Disadvantages

The route maintenance mechanism does not locally repair a broken link. Stale route cache information could also result in inconsistencies during the route reconstruction phase. The connection setup delay is higher. The performance degrades rapidly with increasing mobility.

5.5 AODV(AD-HOC On-Demand Distance-Vector Routing Protocol)[6] Advantages Copyright © 2013 Published by IJESR. All rights reserved

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Routes are established on demand and destination sequence numbers are used to find the route to the destination. The connection setup delay is less.

Disadvantages It a number of stale entries. It leads to heavy control overhead. The periodic beaconing leads to unnecessary bandwidth consumption.

5.6 TORA (Temporally Ordered Routing Algorithm) Advantage By limiting the control packets for route reconfigurations to a small region, TORA insures less control overhead.

Disadvantage Subsequent deletion of routes could result in temporary oscillations and transient loops.

5.7 LAR (Location - Aided Routing) Advantages It reduces the control overhead by limiting the search area for finding a path. Here is efficient utilization of geographical position information It increases the utilization of bandwidth.

Disadvantage • This type of protocol cannot be used in situation where there is no access to GPS infrastructure or similar source of information.

5.8 Associativity-Based Routing Protocols Advantage It results in fewer path break and which in turn reduces the extent of flooding due to reconfiguration of paths in the network.

Disadvantages Here the chosen path maybe longer than the shortest path between the source and destination because of the preference given to stable paths. It may result in high delays during route repairs.

5.9 Signal Stability- Based Adaptive Routing Protocols Advantages It finds more stable routes when compared to shortest path. This protocol accommodates temporal stability by using beacon counts to classify a link as stable or weak.

Disadvantages It consumes a significant amount of bandwidth It also increases the path setup time and path length.

5.10 CEDAR (Core Extraction Distributed Ad-Hoc Routing Protocols) Advantages It performs both routing and QoS path computation very efficiently with the help of core nodes. It provides reliable mechanism for establishing paths with QoS support.


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Disadvantages The movement of core nodes adversely affects the performance of the protocol. It cause significant amount of control overhead.

5.11 ZRP (Zone Routing Protocols) Advantages It reduces the control overhead compared to the Route Request flooding mechanism employed in on-demand approaches and the periodic flooding of routing information packets in table-driven.

Disadvantage It involves large number of overlapping of nodes.

5.12 WBPL (Weight-Based Prefferred Link Algorithm) Advantages It minimizes the broadcast storm problem prevalent in on-demand routing protocols. It has higher scalability compared to other on-demand routing protocols. Reduction in control overhead results in a decrease in the number of collisions and improvement in the efficiency of the protocols.

Disadvantages This type of protocols is computationally more complex than other RouteRequest forwarding schemes.

5.13 FSR (Fisheye State Routing Protocols) Advantages It significantly reduces the bandwidth consumed by link state update packets. It is suitable for large and highly mobile ad hoc wireless networks.

Disadvantages The choice of the number of hops associated with each scope level has a significant on the performance of the protocol at different mobility values and hence must be carefully chosen.

6. CONCLUSION The major challenges that an ad-hoc wireless routing protocol must address are the mobility of nodes, rapid changes in the topology, limited bandwidth, hidden and exposed terminals, limited battery power, time varying channel properties, and location dependent contention. Thus it is concluded that for any routing protocol to be worked efficiently it should have less overhead , limited utilization of band width , minimum number of path breaks and path delays , also less utilization of power resources.

REFERENCES [1] Survey of Routing Protocols for Mobile Ad-hoc Network. Humayun Bakht Taitec College Manchester, United Kingdom International Journal of Information and Communication Technology Research October 2011; 1(6). [2] Khatri N, Kumar A. Analyzing Performance Of AODV In MANET : A Survey. International Journal of Scientific and Engineering Research 2012; 3(6). [3] Nazari V, Ziarati K. Performance Comparison of Routing Protocols for Mobile Ad hoc Networks. IEEE 2006. [4] Ehsan H, Uzmi ZA. Performance Comparison of Ad Hoc Wireless Network Routing Protocols. IEEE INMIC 2004. [5] Bertocchi F, Bergamo P, Mazzin G. Performance Comparison of Routing Protocols for Ad hoc Networks. IEEE GLOBECOM 2003. Copyright © 2013 Published by IJESR. All rights reserved

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[6] Misra R, Manda CR. Performance Comparison of AODV/DSR On-Demand Routing Protocols for Ad Hoc Networks in Constrained Situation, IEEE ICPWC 2005. [7] Jayakumar G, Ganapathy G. Performance Comparison of Mobile Ad-hoc Netwrok Routing Protocol. International Journal of Computer Science and Netwrok Security (IJCSNS) 2007; 7(11). [8] Tuteja A, Mullana RG, Thalia S. Comparative Performance Analysis of DSDV, AODV and DSR Routing Protocols in MANET using NS2. International Conference on Advances in Computer Engineering 2010.


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