COMPARATIVE STUDY BETWEEN UNICAST AND MULTICAST ROUTING PROTOCOLS IN DIFFERENT

DATA RATES USING VANET Dr.Parminder Singh, Assistant Professor, CEC Landran, singh.parminder06@gmail.com

Abstract-Vehicular Ad hoc Network provides a technology for communicating in between different vehicles. ] n this paper the performance of vehicular ad hoc network is evaluated using va rious QOS metrics, which affects the performance of network communication, also analyze the QoS performance with metrics routing overhead, packet delivery ratio and average delay with 1024 bytes packets for unicast routing protocols(Dynamic Source Routing, Ad hoc On demand Distance Vector routing) and multicast routing protocols (Adaptive Demand driven Multicast Routing, On Demand Multicast Routing Protocol) in urban environment . After evaluation results are compared with 512 bytes packets(3) to see the difference in performance of vehicles with different packet size. For investigation it uses the network simulator i.e. ns-2 with a car traffic movement tracing simulator SUMO.VANET simulation is implemented in a 5 0 x 5 0 meters grid model of city environment. The connectivity tests have shown that it is a realistic option to use ad hoc networks for vehicular communication. For unicasting DSR and in case of multicasting ADMR perform better as compared to other protocols.

Index Terms- V ANET, DSR, AODV, ODMRP, ADMR

I. INTRODUCTION

V ANET has become an active area of research, standardization, and development because it has tremendous potential to improve vehicle and road safety, traffic efficiency, and convenience as well as comfort to both drivers and passengers. Recent research efforts have placed a strong emphasis on novel V ANET design architectures and implementations .. V ANET research has attracted a lot of attention from researchers working in various fields including electronics, networking, security software engineering, automotive, transportation, and so on. Recent results covering V ANET -related issues include areas such as routing, Quality Service (QoS), broadcasting, security attacks and threats, capacity, collision and interference, the effects of transmission power on protocol performance and power control algorithms, congestion control, and service discovery. It is beyond the scope of this work to review each of these topics[l] . Routing of data in a vehicular ad hoc network is a challenging task due to the high dynamics of such a network. Communication between vehicles by means of wireless technology has a large potential to improve traffic safety and travel comfort of d rivers and passengers[ 4]. Traditional ad hoc routing protocols have difficulties in dealing with the high mobility specific to vehicular ad hoc networks. Vehicular ad hoc network (VANET) is vehicle-to-vehicle and vehicle-to-infrastructure communications using wireless local area network technologies. In general, V ANET is formed when vehicles need to transmit packets to each other using the wireless channel. Therefore, vehicles need to have wireless transceivers and computerized modules that let the vehicles to act as network nodes. There are a number of characteristics which differentiate V ANET from other types of ad hoc networks. Due to the movement and speed

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of the nodes, VANET's topology is very dynamic compared to traditional mobile ad hoc network (MANET), and because of that, V ANET's network is always partition, especially if the vehicle density is low. Unlike traditional MANET, V ANET does not have any restrictions in term of energy and storage, since nodes in V ANET are cars, not handheld devices[2]. This paper involves evaluation of performance in vehicular ad hoc network with various parameters, for this various protocols from tw 0 c1asses(unicast and multicast) of routing in V ANET are implemented on ns-2 network simulator. Routing is the act of moving information across the network from a source to a destination. It is also referred as the process of choosing a path over which the packets are sent. For this various routing protocols are used and these protocols are different from each other in technology, rules used for routing packets. Routing in vehicles is wide area of research. In this paper routing protocols are implemented to see the performance of those protocols when implemented in V ANETs and for comparison also use different packet size for same protocols. Routing can be done with various ways, in V ANETs unicasting , multicasting is possible and for different routing type different protocol is used. Routing protocols use several metrics as a standard measurement to calculate the best path for routing the packets to its destination that could be. Ad hoc networks are infrastructureless networks. In vehicular networks vehicles act as nodes and in Vehicular ad-hoc networks there is no infrastructure support as is the case with wireless networks, and since a destination node(vehicle) might be out of range of a source node(vehicle) transferring packets; so there is need of a routing procedure. This is always ready to find a path so as to forward the packets appropriately between the source and the destination. Nodes or vehicles in network are arbitrary, network topology changes frequently, bandwidth and battery power in ad hoc networks are limited, topology is unpredictable. All these issues make routing in vehicular environment challenging. Providing protocol for reliable routing in Vehicular Adhoc Environment is still wide area of research.

The remainder of this paper is organized as follows. In Section II, we discuss the related work. Various scenarios and methodology used are provided in Section III. Section IV involves description of simulation setup. Simulation study along with the results and discussion are presented in Section V. Finally, we draw conclusions and future work in Section VI.

II. RELATED WORK

Several studies have been conducted for comparing the routing protocols in MANETs. V ANET is type of MANETs. In our paper, we have varied the number of nodes and based our study entirely on V ANETs. Aslinda Hassan et aI. [2] evaluated the performances of various routing protocols for the Manhattan mobility model and concluded that the multicast routing protocols show a

consistent performance as the number of receivers increase.in our study we evaluate the performance of nodes in vehicular environment by breaking link in DSR. Jagdeep et al. [3] evaluate performance of VANETs nodes with metrics delay, Packet delivery ratio and routing overhead with packet size 512 bytes which is less. In this paper we evaluate the performance with same metrics and protocols but with different packet size and see the effect when implement with different packet size in urban scenarios.

A. Routing in V ANETs Routing is exchange of information between nodes. Protocols are set of rules to exchange data between nodes. Various protocols have been imposed in vehicular environment for routing, on the basis of basic type of routing these protocols are classified as unicast, multicast, broadcast, geocast routing protocols. Papers [8][9][10] discuss various routing protocols in V ANETs and advantages/disadvantages, the applications of various routing protocols for vehicular ad hoc networks and explores the motivation behind the designed, and traces the evolution of these routing protocols. In our study we evaluate the performance of AODV,DSR, ODMRP, ADMR protocols which are classified as:

RolIting prottXolsin VANETs

umca routing protocols

multicast routing protocols

Fig.l. Routing protocols classification

Unicasting is to one-to-one routing i.e one sender and one destination. Multicasting involves one sender and multiple destinations. Reactive routing is demand based routing. It opens the route only when it is necessary for a node to communicate with each other. It maintains only the routes that are currently in use, as a result it reduces the burden in the network. Reactive routing consists of route discovery phase in which the query packets are flooded into the network for the path search and this phase completes when route is found. The various types of reactive routing protocols are AODV, PGB, DSR and TORA[8]. AODV is a reactive routing protocol for MANETs. It operates in two phases namely route discovery and route maintenance[ll]. It has the ability of unicast & multicast routing. It uses a destination sequence number (DestSeqNum) which makes it different from other on demand routing protocols[9].

The Dynamic Source Routing (DSR) protocol presented in [12] which utilize source routing & maintain active routes. It has two phases route discovery & route maintenance. DSR is an on demand routing protocol in which a sender determines the exact sequence of nodes through which a packet is propagated[13]. In tree based multicast routing a sender initially floods a join message to all nodes in the network. Interested nodes reply to the sender via the reverse path. After all reply messages arrive at the sender, a multicast tree rooted at the sender is formed[14]. ADMR is tree based multicast routing protocol. In ADMR a multicast tree is created when a group sender originates a multicast packet for the first time. Interested nodes reply to the sender's packet to join the group. Each multicast packet includes the inter-packet time which is the average packet arrival time from the sender's application layer. The inter-packet time lets tree nodes predict when the next multicast packet will arrive and hence no periodic control messages are required for tree maintenance[18]. Mesh-based multicast protocols try to solve the robustness problem of tree-based protocols. They provide redundancy by using alternative paths in order to mitigate effects of fre-quent topology changes[I7].On-Demand Multicast Routing Protocol (ODMRP) [15] is a reactive mesh based multicast routing protocol. ODMRP uses a forwarding group concept for multicast packet transmission, in which each multicast group G is associated with a forwarding group (FG). Nodes in FG are in charge of forwarding multicast packets of gr oup G. In a multicast group of ODMRP, the source manages the group membership, establishes and updates the multicast routes on demand. Like reactive unicast routing protocols, ODMPR comprises two main phases: the request phase and the reply phase[16]

B. Challenges in V ANETs Main challenges to V ANETs are node density, movement pattern, node velocity,scalability which are to be addressed and keep in mind while designing and implementing routing in vehicular environment[7].Due to dynamic nature of VA NET finding and maintaining routes is considered a challenge. Many investigations have been done in this area and a lot of V ANET routing protocols have been proposed. vehicles in general are constrained to move within road infrastructures (highways, city roads). Furthermore, constraints imposed by this type of environment, namely the radio obstacles (ex: buildings) affect considerably the quality of radio transmissions. Finally, vehicle's mobility is directly related to the driver behaviour. VANET are characterized by a p otentially large number of nodes that are highly mobile (i.e. according to cars' speed). This high mobility can be more or less important depending on road nature (small streets vs. highways). Consequently, a node can quickly join or leave the network in a very short time leading to frequent network partitioning and topology changes. These characteristics imply a weak connectivity reducing the lifetime of the routes. In our current work, we focus on the routing protocol that is suitable for handling the characteristics of such environment[5].

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III. SCENARIO AND METHODOLOGY USED

V ANET simulation is implemented in a 50 x 50 meters grid model of city environment, which is based on Manhattan Grid mobility model, also known as City Section Mobility Model [19]. This model is based on several assumptions. The first assumption is that there are two directions in every street. For vertical direction, mobile node can move either to north or south, whereas for horizontal direction, it is either east or west. Based on this model, it is also assumed that mobile node can only move in the horizontal and vertical lines on the streets . Figure 2 shows the position of nodes in city model that is used for the simulation. The distance between each intersection is by 50 x 50 meters. Traffic lights are used in a number of intersections to replicate the natural city environment. For simplicity, the types of vehicles do not affect the result of the simulation.

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IV. SIMULATION SETUP

A. Mobility model Table 1 shows the mobility mode configuration for this simulation. This paper also used a tool called SUMO, which involves tools to provide a g raphical user interface for traffic mobility tracing and to set the simulation scenario with the parameters in Table I, further which is converted to NS-2 configuration to generate the network traffic trace.

Table I. Mobility Model Configuration

Parameter Value Micro-traffic Simulator Simulation Urban Mobility

(SUMO) Number of vehicles 21 Speed (m/s) 60 m/s Number of lanes 5 Simulation time lOO ms

B. Network model

The network model is simulated using NS-2[20][21] using the mobility trace that is generated by the SUMO engine[22]. Unicast and multicast routing protocols are used to transmit multicast packets to the group of receivers.

I

These nodes are randomly picked without any preferences and the unicast transmissions are done without any background network traffic. The simulation uses two unicast routing protocols as AODV and DSR, two multicast routing protocols- ODMRP and ADMR. These protocols are compared in terms of their performance using the following metrics: - Average end-to-end delay - measures an average delay time from a sender to a destination in second. - Packet delivery ratio - measures the percentage of the transmitted data packets that are successfully received. - Normalized routing load - measures the number of routing packets transmitted per data packet delivered at the destination[2].

Table II. Network Model Configuration

Simulation Parameter Value

Network Simulator NS-2 version 2.34

Area 50 m x 50 m

Number of nodes 21

Maximum speed (m/s) 60 m/s

MAC IEEE 802. l l b

Transmission range 250 meters in radius

Traffic model Constant bit rate (CBR)

Packet size 512 Bytes, 1024 bytes

V. SIMULATION RESULTS

A. Results with with 512 bytes!3) Average Delay with 512 bytes As the number of nodes increases average delay for all protocols increases. For DSR average delay is Jess as compared to other protocols, average delay is between 0 to 5, when number of nodes are upto 6 nodes. Fig 3 shows sudden decrease due to link down in DSR during transmission. After link-up average delay increases as the number of receivers increases. For 1 receiver delay is 0-3 seconds. In ODMRP and ADMR average delay increases with number of receivers. A ODV having maximum average delay. Graph shows no delays upto 2 nodes. After that delay increases with number of nodes. For I receiver delay increases as 4-7 seconds. For ADMR there is minimum delay upto 2 receivers, after that sudden increase and it increases with number of receivers. For single receiver delay of 2-4 seconds for ADMR protocol when size is 512 bytes.

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Average Delay

From figure 5 routing overhead in unicast routing with AODV protocol stays constant, its value does not vary with number of receivers. With DSR protocol routing overhead is minimum as compared to other protocols. Value of overhead stays constant and does not vary with number of receivers. In case of multicast routing for ADMR protocol routing overhead is bit more than DSR. There is small variation in load with variation in number of receivers. For ODMRP protocol overhead is maximum and vary with number of receivers.

B. Results with 1024 bytes Average Delay with 1024 bytes From the figure 3 and figure 6 It has observed that the delay almost same when compared to the data bytes of 512 Bytes and 1024 Bytes.

Average Delayll024 Bytes)

Fig.6. Average Delay(1024 Bytes)

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when packet size is 1024 bytes then average delay os DSR protocol for five nodes increase with value of 0 -3 second. For AODV average delay is highest as compared to other protocols.in starting when number of receivers are less then value of delay vary from 0-3 seconds for 1 node, as the number of receiver increases this value vary 0-4 seconds for 4 nodes. In case of multicast routing with ADMR protocol delay lies between 0 to 3 seconds upto 5 nodes, after that there is sudden increase in delay, it increases with constant value of 1 second per increase in number of node. For ODMRP protocol delay lies between 0 to 3 seconds upto 2 nodes. After that 0 to 5 seconds for single receiver.

Routing Overhead 1024 bytes The simulations conducted proved that V ANET operates in a 1024 Bytes desired and efficient way compared to 512 Bytes and simulation results analyzed almost similar. The very small communication overhead did not affect data transmission in a significant way(see ODMRP Protocol). Even multi-hop connections can be handled without any negative effects using the protocol. This method (V2V Communication) is very suitable for the use in a Vehicular communication environment with highly mobile nodes communicating with other Vehicles.

Routing overhead for lO24 bytes is same as with 512 bytes. From figure 7 routing overhead in unicast routing with AODV protocol stays constant, its value does not vary with number of receivers. With DSR protocol routing overhead is minimum as compared to other protocols. Value of overhead stays constant and does not vary with number of receivers. In case of multicast routing for ADMR protocol routing overhead is bit more than DSR. There is small variation in load with variation in number of receivers. For ODMRP protocol overhead is maximum and vary with number of receivers.

Packet Delivery Ratio with 1024 Bytes From the figure 8, It has observed that PDR almost same when compared to the data Bytes of 512 and 1024 over a same scenario.

282 2014 International Conference on Issues and Challenges in Intelligent Computing Techniques (ICICT)

, PacKet Delivery Ratio(1024 Bytes)

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There is less fluctuation in curve for 1024 bytes as compared to 512 bytes. In unicasting with DSR protocol, maximum value of PDR is 70% . there is sudden decrease in curve due to link down state. For AODV this ratio is 93-99%, i.e highest ratio as compared to other protocols. In case of multicast routing with ADMR this ratio is 70-72% upto 5 nodes. After that upto 7 receivers value of PDR for ADMR protocol is 73-88%, after that there is sudden decrease in value with increase in number of nodes. For ODMRP protocol PDR value for 2 nodes is 91-95 %, after this upto 8 nodes, value remain constant, then there is sudden decrease in value from 95 to 92 %.

VI. CONCLUSION

DSR is best as it has minimum delay and overhead as compared to other protocols, in multicast routing ADMR is better as compared to ODMRP. It is because DSR maintain information and routing information using cache, no need to update it again and again which results in less overhead on network and better performance in terms of va rious metrics even after link has been broken, but DSR in high mobility pattern performs worse. Though performance of AODV is less but it is widely used in networking, as it reduces excessive memory requirements and the route redundancy. AODV responses to the link failure in the network, It can be applied to large scale Adhoc network. AODV is not better as compared to other protocols as it require more time to set connection, more overhead on networking and consume extra bandwidth. In multicasting ADMR is better as compared to other protocols in V ANETs, It utilizes the application data sending pattern to avoid periodic control messages and it can adapt to the change of mobility but the joining and rejoining processes waste bandwidth and take time in ADMR. On the basis of results drawn ADMR having better performance in V ANETs. ODMRP having highest delay, PDR and overhead in V ANET i.e low performance. ODMRP offers

shortest paths reduces data delivery latency. It may be due to reason that it suffers from excessive flooding when there is a large number of senders and the duplicate transmissions that waste bandwidth at low mobility. Various tables given below show performance of these protocols in terms of Average Delay, Packet Delivery ratio and Routing Overhead with 512 and 1024 bytes both and what results show is given in brief.

Table III. Performance comparison of routing with 1024 bytes Parameters DSR AODV ADMR ODMRP

Average Less delay Highest Average Delay

delay delay delay increase with

number of

nodes

Packet Gradually Highest Sudden Mostly

Delivery decrease, PDR, decrease remain

Ratio maximum Value lies

after 7 nodes. constant vary

overhead is between between

70% 92-95%. 93-99%.

Routing Value remain Having Routing Highest

Overhead constant and maximum overhead overhead,

does not vary value of value is bit value vary

with link 2.1800 x more than with

state . having 103, in case DSR, there is variation in

value ofunicast small number of

1.2000xl03 routing. variation receivers,

Value does with number Maximum

not vary of receivers, value is

stable value 2.1900x103

is 1.2800x 103

and

mimimum

value is

2.1000x103

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Parameters DSR AODV ADMR ODMRP

512 bvtes 1024 bvtes 512 bvtes 1024 bvtes 512 bytes 1024 bytes 512 bvtes 1024 bytes Average 0-3 seconds 0-2 seconds 4-7 seconds 3-7 seconds 2-4 seconds Upt05 3-5 seconds Upt02

delay receivers receivers 0-3 seconds, 0-3 seconds, after that 3-5 after that 2-6

seconds seconds

Table IV, Average delay comparison between 512 and 1024 bytes

Table V, Packet Delivery ratio comparison between 512 and 1024 bytes

Parameters DSR AODV ADMR ODMRP

512 bytes 1024 bytes 512 bytes 1024 bytes 512 1024 bytes 512 bytes 1024 bytes bytes

Average Average Highest Less Packet More Remain Highest Highest value, value as variation in fluctuation in

Delivery fluctuation constant, value & PDR with value compared to curve with curve, value Ratio in curve less constant value lies other value lies between

fluctuation variation between 93 between protocols, 90-100% 92-97%. with value 90 to 99%

REFERENCES

[I] Sherali Zeadally et.al. "Vehicular ad hoc networks (V ANETS): status, results, and challenges", Springer Science+Business Media, LLC 2010, Telecommun Syst DOl 10.1 007/s11235-0 I 0-9400-5

[2] Aslinda Hassan et. a/., 'performance evaluation for multicast transmissions in vanet , IEEE CCECE 2011 - 001105

[3] Jagdeep Kaur, Dr.Parminder Singh,"Performance Comparison Between Unicast & Multicast Protocols in Vanet", International Journal of Advanced Technology & Engineering Research (!JATER),pp.109-115, Volume 3, Issue I, Jan. 2013

[4] Christian Lochert et.al. ," A Routing Strategy for Vehicular Ad Hoc Networks in City Environments"

[5] Moez Jerbi et. al.," An Improved Vehicular Ad Hoc Routing Protocol for City Environments ", 2007 IEEE

[6] Pranav Kumar Singh,Kapang Lego, "Comparative Study of Radio Propagation and M obility Models in Vehicular Adhoc Network" International Journal of Computer Ap-plications (0975 - 8887) Volume 16- No.8, February 20 II

[7] Rakesh Kumar et.al.," A Comparative Study of Various Routing Protocols in V ANET", IJCSI International Journal of Computer Science Issues, Vol. 8, Issue 4, No I, July 2011 ,pp-643-684

[8] Bijan Paul et.al.," V ANET Routing Protocols: Pros and Cons", International Journal of Computer Applications (0975 - 8887) volume 20- No.3, April 2011 ,pp-28-34

[9] Fan Li and Yu Wang, "Routing in Vehicular Ad Hoc Networks: A Survey ",University of North Carolina at Charlotte, IEEE vehicular technology magazine I june 2007,pp. 12-22

[10] Saishree Bharadwaj.P et.al..," Performance Evaluation of MANET Based Routing Protocols for V ANETs in Urban Scenarios", 20 II International Conference on Network and Electronics Engineering IPCSlT vol.l I (20 II) (20 I I) IACSIT Press, Singapore.pp.164-169

to 99% 53 to value lies 90% between 70

to 87%.

[II] Johnson, D. B. and Maltz, D. A. (1996), "Dynamic Source Routing in Ad Hoc Wireless Networks," Mobile Computing, T. Imielinski and H. Korth, Eds., Ch. 5, Kluwer, 1996, pp. 153-81.

[12] M.Uma," a comparative study and performance evaluation of reactive quality of service routing protocols in mobile adhoc networks ", Journal of Theoretical and Applied Information Technology, 2009 JATIT, pp. 223-229

[13] Uma Nagaraj et.al.," Study of Various Routing Protocols in V ANET", !JCST Vol. 2, Iss ue 4, Oct . - Dec. 20 I I ,pp. 45-52

[14] S.J. Lee, M. Gerla, C.C. Chiang, "On Demand Multicast Routing Protocol", Proceedings of IEEE WCNC'99, New Orleans, pp. 1298-1302, Sept 1999.

[15] kamal kant et.al," unicast and multicast routing protocols for manets: a comparative survey".

[16] Alberto Gordillo Munoz," Multicast over Vehicle Ad Hoc Networks",

[17] chen-che huang," a comprehensive survey of multicast routing protocols for mobile ad hoc networks", Department of Computer Science and Information Engineering National Dong Hwa University,Taiwan

[18] European Telecommunications Standards Institute, "Selection procedures for the choice of radio transmission technologies of the UMTS; TR 101 112 V 3.1.0 (1997-11)," Tech. Rep., November 1997.

[19] Ke Liu," Network Simulator 2: Introduction",Dept. Of Computer Science, SUNY Binghamton Spring, 2004

[20] The Network Simulator - ns-2 www.isi.edu/nsnamlns.html. [21] Michael Behrisch et.al ," SUMO - Simulation of Urban Mobility An

Overview", Institute of Transportation Systems German Aerospace Center ,germany, The Third international Conference on Advances in System Simulation, SIMUL 2011.

[22] Daniel Krajzewicz,"Recent Development and Applications of SUMO Simulation of Urban Mobility", Published under agreement with IARIA, International Journal on A dvances in Systems and Measurements, vol5 no 3 & 4, year 2012.

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