IJRIT International Journal of Research in Information Technology, Volume 2, Issue 11, November 2014, Pg. 149-160

International Journal of Research in Information Technology (IJRIT)

www.ijrit.com

ISSN 2001-5569

Critical Data Validation in Vehicular Ad Hoc Networks 1

Karthikeyan.K 2 Sandeep Polisetty,3 Swathi Pogadadanda , 4 Sowjayna Vagvala,5Shambhavi Srivastava

1

Associate professor SAS, VIT University,Vellore, Tamil Nadu, India. [email protected], 2 School of Information Technology & Engineering , VIT University, Vellore, Tamil Nadu, India [email protected] 3 School of Information Technology & Engineering ,VIT University Vellore, Tamil Nadu, India [email protected] 4 School of Information Technology & Engineering ,VIT University Vellore, Tamil Nadu, India [email protected] 5 School of Information Technology & Engineering ,VIT University Vellore, Tamil Nadu, India [email protected] ABSTRACT Vehicular Ad hoc networks (VANETS) are the class of mobile Ad hoc networks (MANETS). Vehicles communicate with each other in two ways: (1) Inter vehicle communication and (2) Vehicle to roadside communication. VANETs are based on short-range wireless communication between vehicles. Due to the high mobility of nodes network topology changes occur frequently. Some of the characteristics like unpredictable vehicle mobility, vehicle density, etc differ VANETS from MANETS. Important issues need to be addressed in VANETS are data gathering, data aggregation, data validation, data dissemination, efficient algorithms for media access control (MAC) , routing etc. In this project we provide a solution for data validation issue for critical information like accidents, environmental conditions etc based on the designed threshold value. Threshold value is designed based on number of previously and newly interacting nodes. Proposed work is planned to validate by simulation. The performance parameters evaluated are, Network configuration time, cluster head formation time, data validation time and threshold variation with respect to previously interacted nodes.

Keywords :- Vehicular Ad hoc networks, Threshold value, Data Validation

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I.INTRODUCTION The increasing demand of wireless communication and the needs of new wireless devices have tend to research on self organizing, self healing networks without the interference of centralized or pre-established infrastructure/authority. The networks with the absence of any centralized or pre-established infrastructure are called Ad hoc networks. Ad hoc network refers to a network connection established for a single session and does not require a router or a wireless base station. Ad hoc Networks are collection of self-governing mobile nodes. Vehicular Ad hoc Networks (VANETs) are a specific type of Mobile Ad hoc Networks (MANETs) that are currently attracting the attention of researchers around the world. With pervasiveness of mobile computing technology and wireless communications, VANETs could be a key networking technology of the future vehicle communications, where the communication is possible between vehicles within each other’s radio range as well as with fixed roadside infrastructure components and this could be propagating automated traffic information as well as street surface inadequacy warnings or basically any security issue concerning the traffic following behind, namely on-board active safety systems. VANETS are the envision technology for the intelligent transport system. VANET is the class of Mobile Ad hoc Networks (MANETs), where the nodes are replaced by vehicles

II.RELATED WORKs Recent advances [1] in hardware, software, and communication technologies are enabling the design and implementation of a whole range of different types of networks that are being deployed in various environments. One such network that has received a lot of interest in the last couple of years is the Vehicular Ad-Hoc Network (VANET). VANET 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 VANET design architectures and implementations. A lot of VANET research work has focused on specific areas including routing, broadcasting, Quality of Service (QoS), and security. In this work [5], present a method for accurate aggregation of highway traffic information in vehicular ad hoc networks (VANETs). Highway congestion notification applications need to disseminate information about traffic conditions to distant vehicles. In dense traffic, aggregation is needed to allow a single frame to carry information about a large number of vehicles. Our technique, CASCADE, uses compression to provide aggregation without losing accuracy. We show that CASCADE makes efficient use of the wireless channel while providing each vehicle with data that is highly accurate, represents a large area in front of the vehicle, and can be combined with aggregated data from other vehicles to further extend the covered area. In order to meet performance goals, it is widely agreed that vehicular ad hoc networks (VANETs) must rely heavily on node-to-node communication, thus allowing for malicious data traffic. At the same time, the easy access to information afforded by VANETs potentially enables the difficult security goal of data validation. The work [6] depicts a general approach to evaluating the validity of VANET data. In this a node searches for possible explanations for the data it has collected based on the fact that malicious nodes may be present. Explanations that are consistent with the node's model of the VANET are scored and the node accepts the data as dictated by the highest scoring explanations. The techniques for generating and scoring explanations rely on two assumptions: 1) nodes can tell \at least some" other nodes apart from one another and 2) a

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parsimony argument accurately rejects adversarial behavior in a VANET.Determining whether the number of vehicles reporting an event is above a threshold is an important mechanism for VANETs, because many applications rely on a threshold number of notifications to reach agreement among vehicles, to determine the validity of an event, or to prevent the abuse of emergency alarms. This work [8], present the first efficient and secure threshold-based event validation protocol for VANETs. Quite counter-intuitively, we found that the zsmallest approach offers the best tradeoff between security and efficiency since other approaches perform better for probabilistic counting. The work given in [9] proposes a novel broadcasting scheme for Vehicular Ad Hoc Networks (VANETs) in the service of Intelligent Transportation Systems (ITS). Designing efficient Broadcasting algorithms is critical as a fundamental service in supporting many other applications and protocols. Various broadcasting protocols have been proposed for Mobile Ad Hoc Networks (MANETs) in order to reduce the redundant retransmissions known as the “broadcast storm problem”. By takings advantage of the unique features of vehicular networks, this scheme provides an efficient and stable hierarchical network backbone, and in addition cluster heads and some selected gateway nodes are responsible for rebroadcasting. A simulation study has been conducted in an innovative and realistic vehicular network. The results show that this scheme significantly reduces the number of retransmissions, while improving the reach ability in comparison to other schemes. In this paper [11], they address this challenge by extending the traditional notion of trust to datacentric trust: trustworthiness attributed to node reported data per sec. They proposed a framework for datacentric trust establishment: First, trust in each individual piece of data is computed; then multiple, related but possibly contradictory, data are combined; finally, their validity is inferred by a decision component based on one of several evidence evaluation techniques. Here they consider and evaluate an instantiation of our framework in vehicular networks as a case study. The simulation results show that our scheme is highly resilient to attackers and converges stably to the correct decision. Vehicular networks aimed toward providing roadside services such as traffic alerts, estimated time to reach a destination, alternative routes, and in general improve the efficiency and safety on the road are emerging in both the United States and Europe. Information exchange in such networks occurs between vehicles (inter-vehicle communications) in an ad hoc manner and also with roadside base stations using so-called dedicated short range communication links. Research on technology related to vehicular networks is being conducted by many universities and is being widely reported in the mainstream media as well. Vehicular networks are thus expected to become an important part of community networks of the future. In this paper we will survey the different types of dissemination of information and the assurance of such information in vehicular networks.

III. CONSTRUCTION 3.1 Proposed work This section describes the proposed scheme. Determining whether the number of vehicles reporting an event is above a threshold is an important mechanism for VANETs, because many applications rely on a threshold number of notifications to reach agreement among vehicles to determine the validity of an event, or to

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prevent the abuse of emergency alarms. We present the efficient and secure threshold-based event validation technique for VANETs. In this project we provide a solution for data validation issue for critical information like accidents, environmental conditions etc using threshold based event validation method. We show that threshold-based validation schemes yield significant savings compared to just counting accurately and comparing to the threshold, because threshold-based validation schemes can output an accurate decision based on an inaccurate estimate. The proposed scheme operates in the following phases: 1.

Formation of Clusters in the given network.

2.

Determination of the Cluster Heads.

3. Determination of the Threshold value.

Phase 1: Formation of Clusters in the given networks Vehicles are randomly distributed in the given length and breadth of road. Positions of vehicles are randomly assigned. A vehicle is said to be connected with the other vehicle, if the other vehicle is in the communication range of the first. Communication by forming Clusters is a better approach of communication between highly mobile vehicles of a VANET which is essential for efficient and fast communication in the network. The clusters are done using the length of the road. Entire road of length ‘L’ is devided into 3 segments from 0(L/3),(L/3) –(2L/3) and (2L/3-L) .Thus three clusters are formed for a given length of road ‘L’.

Phase 2: Determination of the Cluster Heads The cluster heads of the clusters are determined using the Connectivity and range of a vehicle. The vehicle with high Connectivity i.e. the vehicle connected with more number of neighbouring vehicles and has the highest range of communication will be chosen as the cluster head of that particular cluster. This cluster head will communicate with the other cluster heads as well as with the vehicles of its own cluster. Thus communication between the vehicles of the network is established through these clusters and cluster heads. Phase 3: Determination of threshold value. Validation of the critical data communicated between the vehicles is done based on this threshold value .Determination of the threshold value and validation of the data using this threshold is done as follows. With ‘n’ as the messages received by cluster head, ’n1 ’as the messages from previously interacted nodes, ’n2’ as messages from newly interacting nodes, the probabilities of these messages is calculated first using the equations (1), (2) respectively. P(n1)=n1/n

------------- (1)

P(n2)=n2/n=1- P(n1) ------------- (2)

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The threshold value is decided using these probabilities using the equation Ti=0.3P(n1)+0.5P(n2) ------------ (3) From Equation 2 Ti =0.5-0.2P(n1)

------------- (4)

Total threshold value for 3 clusters is given by equation (5) T=∑Ti/3

------------- (5)

Total number of messages received by the clusters is given by equation (6) n'=∑ni

------------- (6)

Finally the data validation is performed by comparing the value (n’/vehqty) with the threshold value ‘T’. The data is said to be validated if (n’/vehqty) is greater than the value ‘T’ otherwise data is said to be non valid . Assumptions • • • • • • • •

Each vehicle is equipped with GPS (Global Positioning System), sensors, networking devices, digital map which has the road segment information, and computing devices. Technology used for communication is WiFi Length of each vehicle assumed is 4mts and width is 3mts. There is 1mt safety distance between the vehicles. Vehicles are assumed to be moving in one direction. Attacks that target in exhausting the node battery are not applicable here. Vehicles have the ability of constantly charging their batteries. The vehicle’s power supply is more than enough to support energy-demanding computational systems. As a result, authentication processes do not have to be light-weight.

3.2 Algorithm •

Input: length and breadth of the road [L and B], number of vehicles[n].



Initialization: length and breadth of vehicle le=4mts and wid=3mts.



Step1: Read the L, B and n. if ( vehqty > ((l/(le+1))*(b/(wid+1))) go to step1



Step2: Assign coordinates ,id and speed to all vehicles.



Step3: Formation of clusters for i ←0 to (vehqty-1) { dist = vehi(i).x If (dist>= 0 && dist <= L/3) vehicle belongs to c1 elseif (dist>=(L/3) && dist <= (2L/3)) vehicle belongs to c2 elseif (dist>=(2L/3) && dist <= L) vehicle belongs to c3 }



Step4: Cluster head selection for i ←0 to (vehqty-1)

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for j ←0 to (vehqty-1) { If (Euclidean distance(i.j)< Tx range(i)) Weight(i)++ } If(Weight(i)>large) Cluster haed id =i



Step5: Finding threshold n- messages received by cluster head n1- messages from previously interacted nodes n2- messages from newly interacting nodes P(n1)=n1/n P(n2)=n2/n=1- P(n1) Ti=0.3P(n1)+0.5P(n2) Ti =0.5-0.2P(n1) T=∑Ti/3 n'=∑ni



Step6: output if (T < n'/vehqty) data is valid else

data is invalid

3.3 EXAMPLE SCENARIO

Consider a network in a city scenario where the density of vehicles is more. The vehicles are considered to be moving in the same lane and in a single direction with random mobility. All the vehicles in the network are assumed to be equipped the GPS devices and hence each vehicle in the network knows the position of every other vehicle in the same node. All the vehicles in the network send messages and regular intervals of time which include speed, mobility and position of the vehicle. The user is asked to define the length and breadth of the road .The number of vehicles is defined by the user. Three Clusters are formed in the network based on the position of the vehicles. Cluster heads are selected based on the connectivity of the vehicles. After the cluster heads are formed ,user is asked to enter the source nodes from different clusters .Then threshold value required to validate the message is calculated and based on this threshold value ,the validation of the message is done.3.1 explains example scenario

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Cluster 1

Cluster 2

0

L/3

Cluster 3

2L/3

L

Fig 3.2 Highway scenario [1V] Simulation The simulation of the proposed model is done using C in WINDOWS platform on Pentium-i3 machine. We first discuss a generalized simulation model irrespective of programming language and number of nodes, area under consideration and various parameters. 4.1 Simulation model In the simulation we consider “N” number of nodes in the area of length “L” and breadth “B”, the area L*B may be defined. Mobility for each of these nodes is initialised. The initial positions of the nodes are within the area L*B. Positions and ID s of the vehicles are randomly chosen. The direction of node movement is assumed and remains fixed during simulation. The range of each node is fixed. Range can be same for all nodes. Nodes may enter or leave node’s range during the simulation. We have considered the road with single lane with vehicles moving in same direction. A safety distance of 1meterr for each vehicle is provided. We do not account for any traffic lights or stop signals. It is assumed that all vehicles are equipped with same communication device and knows the position, start time of vehicle and the speed at which it travels. 4.2 Simulation Procedure In this section we briefly outline the simulation procedure of the proposed system. Begin •

Enter the length and breadth of road



Enter the number of vehicles



Clusters are formed and cluster heads are selected



Source vehicle ids from different clusters are entered



Threshold value is calculated



Data is validated based on this threshold value.

4.3 Simulation Inputs To illustrate some results of the proposed VANET simulation, we have taken transmission. Transmission range=100 meters, safety distance=1 meters, the length and breadth can be defined by the user.

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4.4 Performance Parameters •

Network configuration time : It is time required to form the network environment.



Cluster formation time: It is time required to form the clusters from given length of road.



Cluster head selection time : It is time required to choose select cluster head from the cluster.



Data validation time: It is time required to validate the data.

[V] Results Analysis In the figure 5.1 shows that as the number of vehicles increases for the constant length the time required for network configuration time increases because it requires more time to compute each vehicles information like their id, speed, coordinates, etc. In the figure 5.2 shows that as the number of vehicles increases for the constant length the time required for cluster head selection increases because more time is required for calculating the neighbors and deciding the cluster head. In the figure 5.3 shows that as the number of previously interacted vehicles increases , the threshold value will decrease. Larger the percentage of previously interacted nodes less is the spoofing rate, since these vehicles will be validated in the previous session we assign lesser threshold value to these vehicles compared to the newly interacting nodes. In the figure 5.4 shows that as the number of vehicles increases for the constant length the time required for data validation increases. This is because as the number of neighbor nodes increases in a cluster, the time required for the cluster head formation and to calculate the threshold value also increases.

80 70 60 n/w configuration time in ms

50

1000mts

40

1500mts

30

2000mts

20 10 0 10

20

30

40

50

60

No of vehicles /road length Figure 5.1 : Network configuration time v/s Number of vehicles

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25

20 Cluster head formation time in ms

15 1000mts 1500mts 10

2000mts

5

0 10

20

30

40

50

60

No of vehicles/road length Figure 5.2 :Cluster head formation time v/s No of vehicless

0.6

0.5

0.4 Data Validation Threshold of a cluster

0.3

column 1

0.2

0.1

0 0

10

20

30

40

50

% of previously interacted nodes Figure 5.3 : Threshold of a cluster v/s % of previously interacted nodes

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350 340 330 320 1000mts 310 Data validation time In (ms)

1500mts 2000mts

300 290 280 270 10

20

30

40

50

60

No of vehicles/road length Figure 5.4 : Data validation time v/s Number of vehicles

VI.CONCLUSION AND FUTURE WORK VANET is a form of Mobile ad-hoc network, to provide communications among nearby vehicles and between vehicles and nearby fixed equipment (base stations) via radio waves. VANET’s have unique characteristics like high mobility, variation in density of the vehicles on the road with respect to time, routing management, information gathering, validation etc. VANET’s have interesting applications like traffic management, accident avoidance and monitoring of the environmental conditions of the road. This VANET’s will be a successful technology if appropriate information is given to the appropriate vehicles with time. In our project we are performing the data validation based on the threshold value. Threshold value is designed based on number of previously and newly interacting nodes. If the fraction of vehicles sending the message exceeds the designed threshold value, the data is considered to be a valid data. The performance parameters evaluated are, Network configuration time, cluster head formation time, data validation time and threshold variation with respect to previously interacted nodes. In future the work can be extended considering the mobility of the vehicles. Constants used to decide the threshold value can be made dynamic depending on number of times the vehicles interact.

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VII.REFERENCES: [1] Sherali Zeadally, Ray Hunt, Yuh-Shyan Chen, Angela Irwin, Aamir Hassan, ” Vehicular Ad Hoc Networks (VANETS): Status, Results, and Challenges”, Journal of Telecommunication Systems (9 December 2010), pp. 125. [2] Maxim Raya, Jean-Pierre Hubaux,” Securing vehicular ad hoc networks”, Journal of Computer Security 15 (2007)pp 39–68 39 ,IOS Press. [3] Hannes Hartenstein, Kenneth P. Laberteaux,” A Tutorial Survey on Vehicular Ad Hoc Networks”, IEEE Communications Magazine, pp 164--171, June 2008. [4] Prashant Krishnamurthy,”Information Dissemination and Information Assurance in Vehicular Networks: A Survey”, in A Conference Poster in Conference 08`, Los Angeles, Feb. 2008. [5] Khaled Ibrahim, Michele C. Weigle ,”CASCADE: Cluster-based Accurate Syntactic Compression of Aggregated Data in VANETs”, In Proceedings of IEEE AutoNet, New Orleans, LA, Dec. 2008. [6] P.Golle, D.Greene, J.Staddon,” Detecting and correcting malicious data in vanets”, In Proceedings of the first ACM workshop on Vehicular ad hoc networks ,2004. [7] Fabio Picconi, Nishkam Ravi, Marco Gruteser, Liviu Iftode,” Probabilistic Validation of Aggregated Data in Vehicular Ad-hoc Networks “,In proceedings of the 3rd ACM International Workshop on VehiculAr InterNETworking (VANET). pp. 85. ACM (2006). [8] Hsu-Chun Hsiao, Ahren Studer, Rituik Dubey, Elaine Shi, Adrian Perrig.” Efficient and Secure Thresholdbased Event Validation for VANETs”, In Proceedings of ACM Conference on Wireless Network Security (WiSec) , 15-17 June 2011. [9] Fan, Peng,” An Efficient Broadcasting Scheme in Vehicular Networks”, In Proceedings of Consumer Communications and Networking Conference, 2007. CCNC 2007, 4th IEEE. [10] Surabhi Mahajan, Alka Jindal,” Security and Privacy in VANET to reduce Authentication Overhead for Rapid Roaming Networks”, International Journal of Computer Applications (0975– 8887) Volume 1– No.20, February 2010. [11] Maxim Raya, Panagiotis Papadimitratos, Virgil D. Gligor, Jean-Pierre Hubaux ,” On Data-Centric Trust Establishment in Ephemeral Ad Hoc Networks”, IEEE Conference on Computer Communications, April 2008. [12] Chan Yeob Yeun, Mahmoud Al-Qutayri, Faisal Al-Hawi,”Efficient security implementation for emerging vanets”, Ubiquitous Computing and Communication Journal, Vol. 4, No. 4, October 2009. [13] Jiancai, Liu, Chen Feng, and Xu Jiakai. "The study ofrouting strategies in vehicular ad-hoc networks." Wireless Communications and Signal Processing (WCSP), 2010 International Conference on. IEEE, 2010. [14] S.S.Manvi, M.S.Kakkasageri, “Issues in Mobile Adhoc Networks for Vehicular Communication” IETE Technical Review, vol.25, No.2, pp. 59-72, March-April 2008. [15] Bakhouya,M., J. Gaber, and M. Wack. "Performance evaluation of DREAM protocol for inter-vehicle communication." Wireless Communication, Vehicular Technology, Information Theory and Aerospace & Electronic Systems Technology, 2009. Wireless VITAE 2009. 1st International Conference on. IEEE, 2009.

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[16] T. Leinmuller, E. Schoch, F. Karql, “Position verification approaches for vehicular ad hoc networks”, IEEE Wireless Communications 13 (5) (2006) 16–21. [17] V.Casola, J.Serna, J.Luna, M.Rak, M.Medina,”An Interoperability System for Authentication and Authorization in VANETs”, International Journal of Autonomous and Adaptive Communications Systems, Vol. 3, No. 2. (2010), pp. 115-135. [18] Zhen Cao, Jiejun Kong , Uichin Lee , Mario Gerla and Zhong Chen,” Proof-of-Relevance: Filtering False Data via Authentic Consensus in Vehicle Ad-hoc Networks”, IEEE INFOCOM 2008. [19] D. Jungels, M. Raya, I. Aad, J.-P. Hubaux,” Certificate revocation in vehicular ad hoc networks”,Technical Report LCA-REPORT-2006-006, EPFL, 2006.

[20] Y F Ko, M L sim & M Nekovee, wi-fi based broadband wireless access for users on the road, BT Technology journal, vol 24, no 2, pp123-129,April,2006

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Critical Data Validation in Vehicular Ad Hoc Networks

Assumptions. • Each vehicle is equipped with GPS (Global Positioning System), sensors, networking devices, digital map which has the road segment information, and computing devices. • Technology used for communication is WiFi. • Length of each vehicle assumed is 4mts and width is 3mts. • There is 1mt safety distance ...

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