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							                                                                                                                               ISSN: 2277 – 9043
                                                      International Journal of Advanced Research in Computer Science and Electronics Engineering
                                                                                                                    Volume 1, Issue 2, April 2012



         Implementation of Protocol for Efficient Data
          Storage and Data Dissemination in VANET
                                    Nisha K.Warambhe*1 and Dr. S.S. Dorle*2
                        1. Department of Electronics Engg. G.H.Raisoni College o Engg, Nagpur
                        2. Department of Electronics Engg. G.H.Raisoni College o Engg, Nagpur




Abstract— This paper deals with the protocol design for                  Most of the VANET application is based on disseminating
Efficient Data Dissemination and Data Storage in vehicular               data from an information source (data center) to many
adhoc network (VANET). Here a large amount of data is                    vehicles (destination) on the road. Data dissemination in
distributed to a dense vehicular network from roadside unit              VANETs not only helps drivers or vehicles to inform for
as well as from on board unit using WAVE and VIPER                       traffic jams but also to propagate emergency warning
protocol respectively. It is proposed that the system will
                                                                         among the vehicles to avoid collisions. Vehicles on road
consists of one control node as a roadside unit and two mobile
nodes as an on-board unit. Data is disseminated between the              face problems of heavy traffic flow and instability and
mobile nodes via control node using push-based V2V/V2I                   results in road accidents. By forwarding appropriate
dissemination technique, and then data which is disseminated             information to the driver or vehicle on the road like
through control node in all mobile nodes are stored into the             Congestion and traffic management, lots of lives, money,
memory of AVRATMEGA32. Stored data can be retrieved                      and time can be saved. Numbers of innovations have been
for analysis of accident cause or any emergency situation                done to increase safety, comfort, and convenience. Hence,
occurs. Analog to digital conversion is required during                  data exchanging or data disseminating on the roads is
disseminating data between control node and mobile node.                 becoming more and more interesting due to increase in the
The parameters used for the verification of data
                                                                         number of vehicles equipped with computing technologies
dissemination and data storage are Temperature, Location of
vehicle and accident cause which depends on the event                    and wireless communication devices. So data
occurred at the node. Also a hardware model is designed                  dissemination in VANETs plays an important role for
which uses AVR ATMEGA32 micro-controller and RF                          safety and non-safety application.
Trans-receiver module and WINAVR and Cygwin is used for
programming.                                                             Recently, efforts have been started to address data
                                                                         dissemination issues in the VANET. In this approach, a
Index Terms— Vehicular adhoc networks (VANET), Data                      data pouring (DP) and buffering approach to solve the data
dissemination concept, AVR ATMEGA 16 and Transreceiver                   dissemination problem in a VANET is. In DP, data are
module and VANET alert parameter.                                        periodically broadcast to vehicles on the road. In DP with
                                                                         intersection buffering (DP-IB), first data is poured from the
                    I. INTRODUCTION                                      source and then buffered. After that, rebroadcasting at the
Vehicular Ad-Hoc Network is a technology that uses                       intersections is carried out [3]. Also, a mobility-centric
moving cars as nodes in a network to create a mobile                     approach for data dissemination in vehicular networks has
network, comes under the class of mobile ad-hoc networks.                been designed to enhance reliability of the highly mobile,
In VANET, Vehicles are expected to communicate with                      partitioned nature of these networks [4]. In VANET, data
each other (V2V) and with roadside infrastructure (V2I) in               dissemination assumes either that mobile nodes move
order to enhance road safety applications and comfort                    randomly or any two nodes can be expected to be close to
applications such as collision avoidance, emergency                      each other from time to time because they have limited area
message dissemination, dynamic route scheduling, real-                   [5].
time traffic condition monitoring and any kind of
information spreading (i.e. movies, gaming and                           The challenging problem of data dissemination in VANET
advertisement. Hence, Vehicular adhoc network is                         are: the vehicular network consists of a number of data
becoming more interesting in order to provide convenience                sources and data users where each vehicle acts as a data
and efficiency to drivers on the road [1] [2].                           source and user at the same time and unpredictable and




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                                             All Rights Reserved © 2012 IJARCSEE
                                                                                                                              ISSN: 2277 – 9043
                                                     International Journal of Advanced Research in Computer Science and Electronics Engineering
                                                                                                                   Volume 1, Issue 2, April 2012


diverse type of applications like traffic management,                   vehicles, the connectivity among nodes could last only few
situational awareness, and commercial services The aim of               seconds, and fail in unpredictable ways.
data dissemination is to maximum utilize network
resources to fulfill the demand of all users participating in           2. Partitioned networks:
vehicular network. In this paper, the main goal is to solve             Vehicular ad hoc networks will be frequently partitioned.
the data dissemination problem for I2V2V communication                  The dynamic nature of traffic may result in large inter-
scheme and to increase efficiency, convenience, privacy                 vehicle gaps in sparsely populated scenarios, and in several
and safety of drivers and RSU present on the road. The                  isolated clusters of nodes. The degree to which the network
designed protocol can reliably disseminate the data and                 is connected is highly dependant on two factors, such as the
maximize the dissemination capacity. It uses a push based               range of wireless links and the fraction of participant
data dissemination approach where data is efficiently                   vehicles, since only a fraction of vehicles on the road could
pushed to the user present in transmission range. It helps to           equipped with wireless interfaces. Maintaining end-to-end
avoid collision of vehicles, monitoring traffic analysis.               connectivity, packet routing, and reliable multi-hop
                                                                        information dissemination will become extremely
                                                                        challenging in such networks. As it concerns specifically
Paper is divided into two sections; Section II narrates
                                                                        the data transmission in VANETs there are several
review and concept for data dissemination and data storage              additional issues to take into account:
approach and section III, IV and V narrates design for
hardware module and simulated results.
                                                                                  The signal fading, which becomes really fast due
                  II. OVERVIEW                                                     to the surrounding buildings;

A. Need of Data Dissemination and Data Storage in
VANET                                                                             The strong interference and collision related to the
                                                                                   high number of mobile transmitters (vehicles);
Vehicular ad hoc networks face a number of challenges
with the services they provide. The most common                                   The flapping links caused by fading effect and
challenges are in the aspects of security and privacy [7].                         vehicles speed.
With regard to security, VANETs can be exploited to send                These aspects make vehicular networks different and
out improper information to other vehicles [8]. This may be             significantly affect their design. The data dissemination
done for the purpose of either clearing up one's own way or             destination idea has to compete with the limitations of time,
throwing another vehicle out of its way by means of false               space and vehicles. There is a need to introduce push
traffic reports. On the aspect of privacy, VANETs allow                 strategies, where vehicles push data to their neighboring
access to information on speed, status and locations of the             vehicles so that other vehicles can easily access data when
vehicles within its range [9] [10]. This kind of information            necessary. These strategies in turn need to consider the
may be exploited by observers to draw conclusions about a               impact to data caching and aggregation.
driver's personality, lifestyle and social relationships. To
enhance the security and privacy of vehicular network,                  B. Data Dissemination in VANET
Data dissemination and data storage in VANETs must be
accurate. It is extremely important to consider several                 The data dissemination is the process of spreading some
aspects while considering any kind of data transfer or data             amount of data over a distributed wireless network. It is
dissemination in a VANET. Thus the correct approach for                 used to improve the quality of driving in terms of time,
data dissemination in VANETs is necessary to adapt the                  distance, and safety. The data dissemination techniques are
dissemination mechanism according to the different                      classified as follows:
network environments. These aspects include high mobility
and partitioned network [3].                                            1. V2I /I2V dissemination

1. High mobility:                                                       a. Push based: In push based data dissemination, the data is
                                                                        efficiently transmitted from moving vehicles or fixed base
The environment in which vehicular networks operate is                  station (RSU) to another vehicle. Vehicles receive the data
extremely dynamic, and includes extreme configurations:                 when in transmission range of RSU, and then propagate the
in highways, relative speed of up to 300 km/h may occur,                data to other vehicle. In other words, RSU push the data to
while density of nodes may be 1-2 vehicles per kilometer in
low busy roads. Because of the relative movement of the




                                                                                                                                             66
                                            All Rights Reserved © 2012 IJARCSEE
                                                                                                                                     ISSN: 2277 – 9043
                                                            International Journal of Advanced Research in Computer Science and Electronics Engineering
                                                                                                                          Volume 1, Issue 2, April 2012


each vehicle present in transmission range [3] [6]. E.g.:                      roadside unit (RSU) or control node [4]. On board unit is
Traffic condition, e-advertisement etc.                                        installed in each vehicular node and controlled by network
                                                                               operator while roadside unit or infrastructure is available at
 b. Pull based: In Pull based data dissemination; any                          road            and           constitutes            network
vehicle is enabled to request information about specific                       infrastructure.AVRATmega32 micro-controller is used for
location or target. This is also called as request and                         VANET nodes. For wireless communication between the
response model. It is used for user-specific type of data [3]                  both modules, Transreceiver is needed which is interfaced
[6]. E.g.: Enquiry about parking lot, coffee shop etc.                         with the AVRATMEGA32. Following points explains the
                                                                               proposed plan of work.
2. V2V Dissemination
                                                                               1. A Trans-receiver module is connected to every mobile
a. Flooding: In flooding, every node participates in                           node (Vehicle).
dissemination process and the data is created and received                     2. A Trans-receiver module is connected to a control node
in vicinity. It can reliably & quickly distribute data. This                   (Infrastructure).
approach is used for delay sensitive application and also for                  3. Once the vehicle is in range, it would start disseminating
sparse networks during low traffic conditions. But it is not                   data to the vehicles within the vicinity.
suitable for dense network.                                                    4. If two vehicles are close to each other then one of them
                                                                               would slow down the speed, and inform the other vehicle
 b. Relaying: In relaying type of data dissemination, first                    to slow down as well.
the relay node is selected (next hop).Then relay node                          5. The vehicles when in range of the control node would
forwards the data to the next hop and so on. The main                          upload/download all the location based data as well as
advantage of this approach is it reduces congestion and                        weather information of communicating area.
hence, it is used for congested networks or dense network.                     6. This process would be repeated within the system.
Comparison of data dissemination approaches is shown in
table1:                                                                          LCD display of each node w ill display follow ing
                                                                                 data
                             TABLE 1                                                  1. Vehicle Location w ith node number                     Com p u ter
                                                                                      2. Accident Cause
           COMPARISON OF DATA DISSEMINATION APPROACHES                                3. Temperature Measure
 Dissemination             Pros                      Cons
   Approach                                                                                                      Data                Mobile N od e
Push based         Suitable for popular     Not     suitable     for                                             Storage             1 (Vehicle)
                   data                     unpopular data
Pull based         Suitable           for   Cross traffic incurs                                     V2I
                   nonpopular       data,   heavy interferences,                                                                                Data w ill be
                                                                                  Control
                   user specific data       Collisions.                                                                                         d isp layed
                                                                                  N od e (RSU)
Flooding           Reliably and             Not suitable for                                                                  V2V               On LCD of
                   quickly distribute       Dense networks.                                                                                     AVR kit
                                                                                                        Data
                   data                                                                                 Dissem ination
Relaying           Works well in            Selecting best next
                   dense networks           hop & reliability is                                                               Mobile
                                                                                   Data w ill be
                                            difficult                                                                          N od e 2
                                                                                   d isp layed On
                                                                                                                               (Vehicle)
                                                                                   LCD of AVR kit.

Out of four disseminating approaches, Push based
dissemination approach has been used for protocol design                                      FIG 1: BLOCK DIAGRAM OF PROPOSED PLAN
as it is more suitable for transmitting data between the
nodes.                                                                         Fig 1: shows that the data thus obtained from neighboring
                                                                               nodes will be transmitted to all the mobile nodes (vehicles)
III. PRAPOSED DESIGN                                                           via control node which constitutes the V2V communication
                                                                               as well as V2I communication in the network. Depending
A. Basic idea                                                                  upon the data, required action will be taken by driver. Main
                                                                               function of system is to store data which is obtained from
In VANET, basically two nodes are required for the V2V
                                                                               nodes. Three disseminating parameter is used as Vehicle
and I2V communication, called as VANET nodes. These
                                                                               Location with node number, Accident Cause and
nodes are on board unit (OBU) or mobile nodes and
                                                                               Temperature Measure for verifying data dissemination




                                                                                                                                                     67
                                                  All Rights Reserved © 2012 IJARCSEE
                                                                                                                               ISSN: 2277 – 9043
                                                      International Journal of Advanced Research in Computer Science and Electronics Engineering
                                                                                                                    Volume 1, Issue 2, April 2012


approach. Information about all three parameters will be
displayed on LCD display of both control node and mobile                   Antenna                 PCR2A
node. For verification of data storage approach, data
present at each node is uploaded to computer via serial port                                                       RXD
(COM19) and results are verified in MATLAB software.                                                   GN D                    VCC

                                                                                          Transmitter Module
B. Hardware Implementation
                                                                            Antenna               FS1000A
ATMEGA32 comes under the family of AVR .The acronym
AVR has been reported to stand for advanced Virtual RISC                                                          VCC
processor and was developed by Atmel in 1996. AVR is a                                                TXD                     GND
modified Harvard architecture 8-bit RISC single chip
micro-controller. It uses on-chip flash memory for program
storage. Atmega32 is a 40 pin DIP package IC and has 32-                             FIG 2: PIN OUTS OF RECEIVER AND TRANSMITTER
KB of On-chip flash memory. It executes powerful
instructions in a single clock cycle which increases the                 Finally for Temperature measure of surrounding, LM 35 is
ATmega32 throughputs approaching 1 MIPS per MHz and                      used. It is small in size and gives 10mv/°c value output for
allows the system designer to optimize power consumption                 every sensation. Its value is always in analog .Hence, it is
versus processing speed.ATmega32 has four ports as Port                  required to be convert in to digital so after digital
A, B, C and D. Here, Port A acts as A-D converter. Pin no                conversion its input is given to the pin no 40 (ADC0) of IC
1, 2, 3 and 4 of port B are used for input data and pin no 14            ATMEGA32. As ATMEGA32 has internal 10 bit ADC,
and 15 of port D are used for transmitting and receiving                 external ADC is not required. Temperature sensor is used
data between the nodes.ATmega32 AVR is supported with                    only at control node. For sending data of temperature
a full suite of program and system development tools                     measure to all nodes, ADC library of WinAVR has to be
including: C compilers, macro assemblers, program                        used while programming. Small change in temperature
debugger/simulators, in-circuit emulators, and evaluation                measure is transmitted to each vehicle present in
kits.                                                                    communication range of 100m. Each node can store 100
                                                                         readings of temperature measure.
For wireless data transfers between nodes, RF
Transreceiver module is used. RF Transreceiver module                    Complete hardware is going to work on AC/DC adapter of
consists of PCF10 (FS1000A) 433 MHZ as a RF                              +12V. Most of IC are run on the + 5v supply. Hence, L7805
transmitter and PCR2A as a RF receiver. Costs of RF                      IC is used to convert required desired value for operation.
modules are very low and are compact in size. These are                  Four push keys of AVR microcontroller kit are used for
good for short distance and battery power device                         verifying results.
development. Operating frequency range is around
433MHz.         Amplitude      Shift     Keying        (ASK)
or Frequency Shift Keying (FSK) is mainly used for
wireless data transfers. Here, ASK is used for transmission.
Both the receiver and transmitter are quite easy to interface.
Supply voltage range is 3-12V. These low cost RF
transmitter and RF receiver can be used to transmit signal
up to 100 meters (the antenna design, working environment
and supply voltage will seriously impact the effective
distance). It has only single channel. The serial data given
at the input TXD of the transmitter will be received at the
RXD of the receiver. The maximum data rate is around
4KBps. RXD and TXD are TTL compatible. HT series of
encoder/decoder pair IC's are used in RF receiver module
for parallel to serial and the reverse conversion of data.
Both the receiver and transmitter are three terminal devices
with pin outs as shown below.
                                                                            FIG 3: ACTUAL HARDWARE IMPLEMENTATION OF CONTROL NODE AND
                                                                                                      MOBILE NODE
                  Receiver Module




                                                                                                                                              68
                                             All Rights Reserved © 2012 IJARCSEE
                                                                                                                               ISSN: 2277 – 9043
                                                      International Journal of Advanced Research in Computer Science and Electronics Engineering
                                                                                                                    Volume 1, Issue 2, April 2012


Figure 3: shows the hardware implementation for designed                             TABLE 2: PROCESSING STEPS FOR DATA TRANSFER
protocol where AVR ATMEGA 32 kit is interfaced with the
RF transmitter and RF receiver.                                            Processing Steps       Parameters to be select by vehicle
                                                                                Start of
                                                                             transmission
IV DESIGN APPROACH FOR DATA DISSEMINATION
AND DATA STORAGE IN VANET                                                   Node Number                        Node 1 or Node 2
                                                                              Event Type             Check point Event or Accident Event
The main purpose of all VANET applications is to enhance
the vehicular communication between vehicles as well as
infrastructure. In designing approach, WAVE (Wireless                       Event Number           Check point 1 or Check point 2 or Check
Access for Vehicular Environment) protocol is used for                                                       point 3 or Accident
data transfer in V2V communication [11] while VIPER
(vehicle-to-infrastructure   communication        privacy                       End of
enforcement) protocol is used for data transfer in V2I                       transmission
communication [13]. In this section, various aspects have
been used for designing purpose. First, the coding                       After End of transmission, the data is then sent to
technique is presented, which play a key role in the                     respective node.
dissemination problem. Next, the set of rules that govern
data transfer is described.                                              V. SIMULATION RESULT

A. VANET Alert parameters                                                According to VANET alert parameter, Simulation results
                                                                         are taken. WINAVR tool is used for programming purpose
The conventional approach to reduce collisions and the                   while compilation of programs is done using Cygwin tool.
hidden node problem in network is using the VANET alert
parameters. Two Alert parameters have been declared for
data transfer as Vehicle location and Vehicle accident.
These parameters are defined for each mobile node in the
network. Also temperature measure is defined for weather
information of communication area, which helps to
understand the design approach for data dissemination and
data storage in VANET. All the three parameters stores 100
readings in the memory of Atmega 32. One more important
thing is consider when there is a change in temperature, it
shows that change at mobile nodes first and then at control
node, which in turn reduces time constraints.

B. Processing Steps for Data Transfer

For data transfer between the control node and mobile
nodes, three parameters (Temperature measure, Vehicle
location and Vehicle accident) are decided as a VANET
alert parameter. For these parameters, four events are
defined as three events for check point and one event for
accident. Whenever an event is occurred at any node,
control node check out the type of event and number of
type. After verification of event, the data of the respective
event is transmitted to different nodes. If the mobile node is
damaged due to any circumstances, data is stored in the                                     FIG 4: TEMPERATURE DISSEMINATION
respective node always. Processing steps for data transfer is
given below:
                                                                         Fig 4: shows that Temperature Dissemination between
                                                                         control node and mobile nodes. Temperature at each node
                                                                         is 31°c.




                                                                                                                                              69
                                             All Rights Reserved © 2012 IJARCSEE
                                                                                                                                    ISSN: 2277 – 9043
                                                     International Journal of Advanced Research in Computer Science and Electronics Engineering
                                                                                                                   Volume 1, Issue 2, April 2012


                                                                        VI. CONCLUSION
                                                                        This paper deals with the design of a protocol for efficient
                                                                        Data storage and data dissemination in vehicular adhoc
                                                                        network. WINAVR and Cygwin are chosen as the
                                                                        implementation tool because of the close integration with
                                                                        AVR micro-controller family, which also allows close
                                                                        coupling of the MATLAB model with the equivalent
                                                                        hardware implementation. After the testing of the VANET
                                                                        alert parameters, it is observed that using AVR
                                                                        microcontroller data is easily stored and disseminated at
                                                                        node. As the AVR atmega 32 has 32 bit on chip flash
                                                                        memory, external memory is not required which in turn
                                                                        reduces the cost.

                                                                        VII. FUTURE WORK
                                                                        Results obtained for temperature dissemination, location
                                                                        detection and accident detection can be further verified
                                                                        using MATLAB tool. Graphs for each result will help to
                                                                        understand the concept of data storage and data
                                                                        dissemination approaches of VANET.

                                                                        REFERENCE
                  FIG 5: LOCATION DETECTION                             [1] M.L. Sichitiu, and M. Kihl, “Inter-Vehicle Communication Systems: A Survey,”
                                                                        in IEEE Communications Surveys and Tutorials, vol. 10, no. 2, pp. 88-105, 2008.
Fig 5: shows the result for location detection where check              [2] M. D. Dikaiakos, S. Iqbal, T. Nadeem, and L. Iftode, “VITP: An information
point event has been detected at location 1 and then it is              transfer protocol for vehicular computing,” in Proc. ACM VANET, 2005, pp. 30–39.
disseminated and data is stored at node2.
                                                                        [3] Jing Zhao, Student Member, IEEE, Yang Zhang, Student Member, IEEE, and
                                                                        Guohong Cao, Senior Member, IEEE. Data Pouring and Buffering on the Road:A
                                                                        New Data Dissemination Paradigm for Vehicular Ad Hoc Networks. IEEE
                                                                        TRANSACTIONS ON VEHICULAR TECHNOLOGY, VOL. 56, NO. 6,
                                                                        NOVEMBER 2007.

                                                                        [4] Hao Wu and Richard Fujimoto Randall Guensler and Michael Hunter MDDV: A
                                                                        Mobility-Centric Data Dissemination Algorithm for Vehicular Networks.

                                                                        [5] Heinzelman,W, W., Kulik, J. and Balakrishnan, H., Adaptive Protocols for
                                                                        Information Dissemination in Wireless Sensor Networks. in ACM Mobicom'99,
                                                                        (1999).

                                                                        [6] T. Nadeem, P. Shankar and L. Iftode, “A Comparative Study of Data
                                                                        Dissemination Models for VANETs” In 3rd ACM/IEEE Annual International
                                                                        Conference on Mobile and Ubiquitous Systems: Networks and Services
                                                                        (MOBIQUITOUS 2006), 2006, pp. 1-11.

                                                                        [7] Tian, J. and Rothermel, K. Building Large Peer-to-Peer Systems in Highly
                                                                        Mobile Ad Hoc Networks: New Challenges? Technical Report 2002/05, University
                                                                        of Stuttgart, 2002.

                                                                        [8] M. Raya and J.-P. Hubaux. Securing Vehicular Ad Hoc Networks. Journal of
                                                                        Computer Security, Special Issue on Security of Ad-Hoc and Sensor Networks,
                                                                        15(1):39 – 68, 2007.
                  FIG 6: ACCIDENT DETECTION
                                                                        [9] Cencioni, P. Di Pietro, R.Univ. di Roma, Rome. VIPER: A vehicle-to-
                                                                        infrastructure communication privacy enforcement protocol. In IEEE International
Fig6: shows the result for accident detection where                     Conference on Mobile adhoc and sensor network, pages 1 – 6, Oct. 2007.
accident event has been detected at location 1 and then it is
disseminated and data is stored at both nodes 1 and 2.                  [10] K. Sampigethaya, L. Huang, M. Li, R. Poovendran, K. Matsuura, and K.
                                                                        Sezaki. "CARAVAN: Providing Location Privacy for VANET". In Proceedings of
                                                                        the Embedded Security in Cars (ESCAR) Workshop, 2005.




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                                              All Rights Reserved © 2012 IJARCSEE
                                                                                                                                           ISSN: 2277 – 9043
                                                                  International Journal of Advanced Research in Computer Science and Electronics Engineering
                                                                                                                                Volume 1, Issue 2, April 2012



[11] Marica Amadeo, Claudia Campolo, Antonella Molinaro, Giuseppe Ruggeri, A
WAVE-compliant MAC Protocol to Support Vehicle-to-Infrastructure Non-Safety

[12] Mohsen Sardari, Faramarz Hendessi and Faramarz Fekri,DDRC: Data
Dissemination in Vehicular Networks Using Rateless Codes* in Journal of
Information science and Engineering 26, 867-881 (2010).

[13] Paolo Cencioni and Roberto Di Pietro, VIPER: A Vehicle-
Infrastructure Communication Privacy Enforcement Protocol.

[14] W. Gao and G. Cao. On Exploiting Transient Contact Patterns for
Data Forwarding in Delay Tolerant Networks. In Proceedings of ICNP,
pages 193–202, 2010.




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