AODV Routing Protocol Modification with Broadcasting RREQ Packet in VANET

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International Journal of Emerging Technology and Advanced Engineering

Website: www.ijetae.com (ISSN 2250-2459,ISO 9001:2008 Certified Journal, Volume 4, Issue 8, August 2014)

439

AODV Routing Protocol Modification with Broadcasting

RREQ Packet in VANET

Soumen Saha

1

, Dr.Utpal Roy

2

, Dr. D.D. Sinha

3 1_{Dept of CST, ICVP Jhargram, West Bengal}

2_{Department of Computer & System Sciences Siksha-Bhavana, Visva-Bharati} 3

Dept of CSE University of Calcutta, Kolkata, India

Abstract-- Now a days a new ad-hoc type network is introduce for vehicle. This can be use for all type Vehicle propagation control in city and highway road map. This is called vehicle ad-hoc network (VANET). There is several open research topic for this VANET. The different routing protocols is used for this VANET . Such as Ad-hoc on Demand Distance Vector protocol(AODV) [1], Distance Routing Protocol(DSR)[1], adaptive distance vector protocol (ADV)[2] etc. The implementation and testing of those protocol is very costly and difficult in real life situation. Therefore we need some simulator for this purpose. Such as NCTUns, NS3, SUMO, OMneT++, MiXiM, Dia, Subversion (SVN). NCTUns-6.[3] is such kind of simulator so that it has graphical environment which help us to draw the various kind of graph easily and implement various types of routing protocol on this graph. Hear all well known routing protocol is available. But we found AODV is implemented on broadcast to it’s own network but multicast for global VANET network. Therefore it seems a wastage of Route Request(RREQ)[1] packet for it’s neighbour networks. Therefore we modify the conventional AODV to broadcast to global network and we got an enchantment in throughput for our modified AODV(MAODV).

Keywords--- VANET, Ad-hoc network, IP broadcast, AODV, Throughput, Packet Drop, Packet Collision, NCTUns6.0 network simulator.

I. INTRODUCTION

In VANET the different routing protocol work on ad-basis formed network(Fig.1). But, the ad-network is highly unstable as there is speed is important factor in VANET. The members of formed ad-hoc network when out of the range of the existing ad-hoc network, it may fails to move. Therefore, we need some external equipment(road side equipment) to help those node(Vehicle) to move. But, other than that if we taken the existing other Ad-hoc network, to help the re communicate with that isolate node (Vehicle), it will be more economic, as we do not need any extra equipment.

Fig1: Ad-hoc VANET

II. LITERATURE SURVEY

Earlier we have studies over VANET and found some different routing protocol performance[4-7] . There we have obtained the result for different scenario[4,5], different routing protocols [7], different type of data[6]. We finally found AODV is better than other routing protocol in VANET for non real time data.

We also studies the S.Y. Wang et al. [3], where we found the NCTUns[10,11] simulator for the VANET simulation. This simulator is such kind of simulator so that it has graphical environment which help us to draw the various kind of graph easily and implement various types of routing protocol on this graph. Hear all well known routing protocol is available. But, we found AODV is implemented on broadcast to it’s own network(ie basically multicast) but multicast for global VANET network. Therefore it seems a wastage of Route Request(RREQ)[1] packet for it’s neighbour networks.

III. PROPOSED WORK

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Now there is a situation, where a node (vehicle) is out of range of a communication node of left side (1.0.0.0/16) network. Therefore in this situation the out of range node will fail to communicate. But, according to our proposal, right side (2.0.0.0/16) network running with modified AODV routing protocol(MAODV) will help in this situation(Fig.2) to the node within the range of this network, as it is designed for broadcast(255.255.255.255).

Therefore the node has link breakage of right side network also able to communicate with left side ad-hoc network with the help of right side ad-hoc network.

Fig2: MAODV broadcast it’s packet

We have taken AODV(Fig.3) protocol for the routing as we found in our previous paper[4], this AODV is best performance compared to other routing protocols.

Fig3: AODV works[1]

Performance metrics

Different performance metrics are used to check the performance of routing protocols in various network environments. In our study we have selected throughput and packet drop to check the performance of VANET routing protocols against each other. The reason for the selection of these performance metrics is to check the performance of routing protocols in highly mobile environment of VANET. Moreover, these performance metrics are used to check the effectiveness of VANET routing protocols i.e. how well the protocol deliver packets and how well the algorithm for a routing protocol performs in order to discover the route towards destination. The selected metrics for routing protocols evaluation are as follows [8,9].

1) Throughput

Throughput is the average number of successfully delivered data packets on a communication network or network node. In other words throughput describes as the total number of received packets at the destination out of total transmitted packets [8]. Throughput is calculated in bytes/sec or data packets per second. The simulation result for throughput in NCTUns6.0 shows the total received packets at destination in KB/Sec, mathematically throughput is shown as follows:

Total number of received packets at destination* packet size Throughput (bytes/sec) = ---

Total simulation time

2) Packet Drop

Packet drop shows total number of data packets that could not reach destination successfully. The reason for packet drop may arise due to congestion, faulty hardware and queue overflow etc. Packet drop affects the network performance by consuming time and more bandwidth to resend a packet. Lower packet drop rate shows higher protocol performance.

3) Collision

The Collision of data packet is the number of packets collides to each other due to congestion. It affects the performance directly on the bandwidth. Lower packet collision rate shows higher protocol performance.

IV. RESULT AND ANALYSIS

A. Simulator

There are several types of simulator such as NCTUns, NS2, NS3, SUMO, OMneT++, MiXiM, Dia, Subversion (SVN). But we have chosen NCTUns-6.0 for simulation of our work. Before real-time testing we have run our work by using this simulator.

The main characteristics[10] of NCTUns-6.0 are given below(Fig.4)

 It directly uses the real-life Linux TCP/IP protocol stack to generate high-fidelity simulation results

 It can run up any real-life UNIX-based application program on a simulated node without any modification.

 It can use any real-life UNIX network monitoring tools

 Its setup and usage of a simulated network and application programs are exactly the same as those used in real-life IP networks

 It simulates many important networks.

 It simulates many important protocols.

 It finishes a network simulation case quickly

 It generates reliable and repeatable simulation results.

RREQ DATA RREP

AODV(1.0.0.0/16) With 1.0.255.255 multicast

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 It provides a highly-integrated and professional GUI environment

 It adopts a module-based architecture.

 It can be easily used as an emulator.



It supports seamless integration of emulation and simulation.

Fig.4 NCTUns6.0 simulator

B. Testing scenario conditions of VANET:

 Network is taken ad-hoc and the path is absolutely dynamic in nature.

 Lane Width is taken 30m

 Initial average distance is 500m in between different car.

 Simulation time is taken 400sec on average

 RTS threshold is 3000bytes

 The car profile is taken five (20%---speed is 18km/hour, speed is 36km/hour, 20%---speed is 50km/hour, 20%---speed is 60km/hour,20%---speed is 80km/hour)

 Number of lane is taken 2

 Number Network is taken 2(one of 1.0.0.0/16 net id another is 2.0.0.0/16 net id)

TABLE1

SIMULATIONS ENVIROMENT PARAMETER FOR VANET

Frequency (MHz) 2400

fadingVar 10.0

RiceanK 10.0

TxAntennaHieght (m) 1.5

System Loss 1.0

Trans Power (dbm) 3.0

AverageBuilding Height (m) 10

Street Width (m) 30

Average Building Distance (m) 80

Path Loss exponent 2.0

Shadowing Standard Deviation 4.0

CloseInDistance (m) 1.0

RxAntenna Height (m) 1.5

Number of Cars is taken for each network

5,15,25

Fig5: Simulation Scenario

The above scenario(Fig.5) designed with left side road structure with 1.0.0.0/16 sub net id and right side rode structure with 2.0.0.0/16 subnet id. And AODV run with Multicast in same network (1.0.255.255).But, MAODV run with broadcast (255.255.255.255) to left and right side both

C. Result:

I. car 5 of each network

1. Packet Broadcast output for car 5 of each network

Fig6: AODV Vs MAODV IP broadcast graph (X-axis is time in Sec and Y-axis is kb/sec)

We have found result in Fig. 6, our modified AODV (MAODV) working principal is almost same in number of packet for broadcast purpose compared to multicast in original AODV working principal in NCTUns simulator.

2. Collision of packets

The packet collision number is drastically reduced in the MAODV approach (Fig. 7). As the traffic is less and the left side(1.0.0.0/16) nodes absorbs the some right side(2.0.0.0/16) and this network packets is not confined within the network.

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International Journal of Emerging Technology and Advanced Engineering

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3. Drop of Packets

Fig8: Number of Packet drop in AODV vs MAODV(X-axis is time in sec and Y-axis number of packets)

The packet drop also much less in MAODV scheme (Fig.8), as it absorbs more compared to multicast.

4. In packet throughput to nodes

Fig9: In throughput of AODV vs MAODV(X-axis is time in sec and Y-axis is throughput in kb/sec)

The above Fig.9 indicates the in throughput is less for right side network (2.0.0.0/16) as it receive the same number of packet from it’s own network. The neighbour network (1.0.0.0/16) will not able to send any packet to the right side network as it is different network.

5. Out packet throughput to nodes

Fig10: Out throughput of AODV vs MAODV(X-axis is time in sec and Y-axis is throughput in kb/sec)

In Out throughput (Fig.10) we found almost same throughput for both AODV and MAODV. But, the interesting fact is, that the out throughput is same for both, although the AODV encounter more drop of packet and more packet collision. Therefore our proposal (MAODV) is better in terms of less packet drop and less collision.

Next we try to test further on more dance traffic situation.

II. car 15 of each network

1. Packet Broadcast output for car 5 of each network

Fig11: AODV Vs MAODV IP broadcast graph (X-axis is time in Sec and Y-axis is kb/sec)

Fig:12: Number of Packet in collision in AODV vs MAODV(X-axis is time in sec and Y-axis number of packets)

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International Journal of Emerging Technology and Advanced Engineering

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Hear we found the number of packet broadcast is again same for both(fig.11) . But the number of packet in collision(fig.12) and packet drop(fig.13) incising as the traffic incises. But incoming packet throughput (fig.14) is looks reveres with AODV compared to MAODV. As, traffic incises, the LHS side traffic need less reuse of neighbour (RHS) side packet for maintaining Ad-hoc network. But finally the out packet throughput is remain same(fig.15 )

III. car 25 of each network

1. Packet Broadcast output for car 5 of each network

Fig16: AODV Vs MAODV IP broadcast graph (X-axis is time in Sec and Y-axis is kb/sec)

Fig:17 Number of Packet in collision in AODV vs MAODV(X-axis is time in sec and Y-axis number of packets)

Fig19: In throughput of AODV vs MAODV(X-axis is time in sec and Y-axis is throughput in kb/sec)

On third testing results(fig.16-20) indicates almost same result compared to second test (15 car each side scenario)

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V. CONCLUSION AND FEATURE WORK

We have found a very interesting result in Fig. 6-10 that, our modified AODV (MAODV) working principal is far better in the link breakage and low traffic density situation. The performance with respect to broadcast throughput and Out throughput both situation is same compared to conventional AODV working principal in NCTUns simulator.

The only drawback of this proposal is, it will not work better if traffic density is more. As, the number of packet will increase (Fig.11-20) the performance is not progressive in our proposal. Hear the other network’s packet is not required for the neighbor. But it increases the unnecessary traffic density and it causes more packet drop and collision.

Therefore we have to propose some modification over the new scheme to reduce the overhead to the nodes.

REFERENCES

[1] RFC of AODV,DSR: www.ietf.org/rfc/rfc3561.txt ,

www.ietf.org/rfc/rfc4728.txt

[2] Boppana, et al. “An adaptive distance vector routing algorithm for mobile, ad hoc networks” INFOCOM 2001.IEEE Xplore,Vol-3, 1753 – 1762, 2001.

[3] S.Y. Wang et al. The Design and Implementation of the NCTUns 1.0 Network Simulator, Computer Networks, Vol. 42, Issue 2, June 2003, pp. 175-197.

[4] Soumen Saha, Dr. Utpal Roy, Dr.D.D. Sinha, Md. Arif , “Performance Analysis of VANET Scenario in Ad-hoc Network by NCTUns “, IJICT (ISSN 0974-2239) ,Vol-3, No-7 ,575-581 ,2013

[5] Soumen Saha, Dr. Utpal Roy, Dr.D.D. Sinha ,“VANET Simulation in diffrent Indian City Scenario” ,IJEEE(ISSN 2231-1297), Vol-3, No-9,2013

[6] Soumen Saha, Dr. Utpal Roy, Dr.D.D. Sinha, “Comparative study of Ad-Hoc Protocols in MANET and VANET” , IJEEE(ISSN 2231-1297) , Vol-3, No-9,2013

[7] Soumen Saha, Dr. Utpal Roy, Dr.D.D. Sinha , ”Performance comparison of various Ad-Hoc routing protocols of VANET in

Indian city scenario”, published at AIJRSTEM,

(ISSN(Online):2328-3580), Issue 5, Volume 1, 49-54, Feb 2014. [8] Francisco J. Martinez1, Chai Keong Toh, Juan-CarlosCano,

Carlos T. Calafate and Pietro , A survey and comparative study of simulators for vehicular and hoc networks (VANETs), published at Wairless communication mobile computing of Special Issue: Emerging Techniques for Wireless Vehicular Communications of Wiley online Publication, July 2011 , Volume 11, Issue 7, pages 813–828

[9] H. Kawashima, “Japanese Perspective of Driver Information Systems,” Transportation,vol.17,no. 3, Sept. 1990, pp.263–84 [10] The GUI User Manual for the NCTUns 6.0 Network Simulator

and Emulator. http://nsl.csie.nctu.edu.tw/nctuns.html- NCTUns-6.0 manual