Essay: VANET based secure and efficient transportation system

Abstract -This paper presents a recent advance of vehicular technology (VANET) offers many opportunities for developing new navigation systems to overcome the problem of popular global positioning system (GPS)[1], based navigation systems. The main objective is to propose a navigation scheme that utilizes the online or real time road information collected by a VANET to guide the drivers to desired destination .In order to integrate vehicular technology into conventional GPS based navigation systems securely, a secure and privacy preserving navigation is required. Addition to authentication and privacy preserving this VSPN scheme fulfills all necessary security requirements. In this scheme the concept of proxy re-encryption scheme and anonymous credentials are used.
Index terms-Vehicular ad-hoc network, proxy re-encryption, anonymous credentials, GPS.
1.INTRODUCTION
Vehicles have become an important part of human daily life. Finding a route to a certain destination is a common experience for all drivers. In the old days, a driver usually refers to a hardcopy (map) of the atlas. The drawbacks are quite obvious. After some days a Global Positioning System (GPS) based navigation system become popular.GPS is a space based satellite navigation system that provides location and time information in all weather conditions anywhere on the earth.
In GPS system a small hardware device is installed on a vehicle by receiving GPS signals the device can determine its current location and then find a shortest route to a certain destination. Route searching procedure based on a local map database and real-time road conditions are not taken into account. To know about real-time road conditions, a driver needs another system known as Traffic Message Channel (TMC)[2].It makes use of the FM radio to broadcast real-time traffic and weather information but also driver cannot obtain information like the general fluency of a road from TMC.
Vehicular ad-hoc network (VANET) represents a challenging class of Mobile ad-hoc network (MANET). Ad-hoc network is a Local Area Network (LAN) that is built spontaneously as devices connect. Basically ad-hoc network is a temporary network connection created for a specific purpose. MANET can change locations and configure itself. VANETS are considered as one of the most prominent technologies for improving the efficiency and safety of modern transportation system.
VANET enables vehicles to intelligently communicate with each other and with road side infrastructure. In this communication nodes are mainly vehicles. Vehicular communication networks, which are also referred to as Vehicular ad- hoc Networks (VANETs) inherently provide us a perfect way to collect dynamic traffic information and sense various physical quantities related to traffic distribution with very low cost and high accuracy. The main objective of VANET is to provide safety to vehicles such as collision alert, road surrounding warnings, vehicle speed etc..Recently vehicular ad-hoc network become popular in many countries. It is an important element of intelligent transportation systems.
The vehicular communication system is made over this robust and strong IT system. It helps vehicle’s driver in information sharing, co-operative driving and other value added services which makes the driving more safe, e’cient and convenient on roads. The communication between vehicles are ad-hoc in nature where communications are done between various infrastructure and cars. This special kind of communication network is known as ‘Vehicular Ad-hoc Network (VANET)”.
A VANET turns every participating car into a wireless node allowing cars approximately 100 to 300 meters of each other to connect and in turn , create a network with a wide range. Here multiple hop communication takes place between the cars, connecting vehicles to one another so that a mobile internet is created. The first systems that will integrate this technology are police and fire vehicles to communicate with each other for safety purposes.
Today’s vehicles are become a smart car with assistance from wireless communication technology. Smart cars are fully controlled software devices. In a typical VANET vehicles are equipped with 3 different devices namely On Board Unit (OBU), Sensors, Tamper proof device (TPD).
OBU is a device inside the vehicle .It processes the data collected from various sensors fitted inside the car and give conditions of the vehicle. It is responsible for communication with outside network i.e with other vehicles and infrastructure. Sensors are used for sensing purpose and to measure their own status of the car (fuel consumption of the car) .TPD is a safety device installed inside the vehicle. It contains all the vehicles safety information, a battery and a watch for synchronization. It participates into all safety operation and it is only reasonable for the authorised person.
Road side units (RSU) installed along the roads.RSU and OBU are continuously communicating with each other using dedicated short range communication protocol.
Fig 1: Overview of VANET
The overview of VANET is shown in the fig1
Here the RSU and OBU communicate using DSRC protocol which uses 5.85 to 5.92GHZ.Its approximate range is 1000m.The vehicle to vehicle or vehicle to infrastructure communication takes place
Basic components of VANET
Fig 2 shows the basic components used in the VSPN scheme. Those are RSU, OBU, Tamper proof device, sensors.
Fig 2 :Basic components of VANET
The communication between vehicles and other communicating devices uses 802.11p wireless standard for supporting Dedicated Short Range Communication (DSRC) protocols.
Vehicles A,B,C,D, and E in fig2 communicate with each other using DSRC protocol. But vehicle C cannot communicate directly with vehicle E as the range of the DSRC 802.11p is limited to approx.1000m.Vehicle c can receive the messages from E through the D. Here multi hop communication takes place
OBU is responsible for communicating with other vehicles and infrastructure. Communication between vehicle to vehicle and vehicle to infrastructure are ad-hoc in nature.
RSU is a infrastructure component that communicates with the vehicles and other roadside stations for sharing and collecting data from various vehicles. Additionally, it helps in sharing and receiving various information between vehicles and process data information.
Problem statement
Every vehicle has a Tamper proof devices and each device will be navigated to Road Side Units (RSU) since there will be multiple RSU and which are interlinked to each other. Hence if 1 RSU compromises the whole network gets attacked since general encryption algorithms are not completely available for providing good security module.
Adversary (attacker) module
1. Attacker can trace the real identity of any vehicle and can reveal a vehicle’s real identity by analyzing multiple messages sent by it.
2. Attacker can obtain the containt of any navigation query and navigation result by means of eavesdropping.
3. Attacker can link up a vehicle’s query with it’s real identity by colluding with RSU and TA.
Objective of VANET
Improve traffic safety and comfort of driving
Minimize accidents, traffic intensity, locating vehicles.
Up-to-date traffic information.
Intersection collision warning.
Local danger warning.
Weather information.
Security requirements
1.Message integrity: All messages which are sent and received on the network should be protected against alteration attacks. A message can be altered in the several ways during its transit from source to destination.
2.Authentication:Without authentication hackers or malicious users can inject false messages into the network and confuse other vehicles by distributing false information.
3. Identity privacy preserving: The real identity of a vehicle should be kept unknown from other vehicles as well as from RSU.
4. Traceability: Vehicles real identity should be hidden from other vehicles and RSU.TA (Trusted authority) should have the ability to obtain a vehicles real identity.
5. Confidentiality: The content of a query and navigation result should be kept confidential.
PRILIMINARIES-BILINEAR MAPS
Bilinear maps: Bilinear maps will be used to create a pairwise key. Our security schemes are pairing based and defined on two cyclic groups with a mapping called bilinear map[24].
Let G be a cyclic multiplicative group with generator g and Gt be another. both groups G and Gt have the same prime order q.The mapping e^:GXG’Gt is called a bilinear map if it satisfies the following properties.
1.Bilinear.
2. Nondegenerate.
3. Computable.
Proxy re-encryption scheme: A proxy re-encryption scheme is similar to a traditional symmetric or asymmetric encryption scheme with the addition of a delegation function.
Proxy re-encryption schemes are cryptosystems which allow third parties to alter a ciphertext which has been encrypted for one party, so that it may be decrypted by another .
The message sender can generate a re-encryption key based on his/her own secret key and the delegated user’s key. A proxy can then use this re-encryption key to translate a ciphertext into a special form such that the delegated user can use his/her private key to decrypt the ciphertext[25][26].
OUR SOLUTIONS-VSPN
This section presents our VANET based secure and privacy preserving navigation (VANET) scheme.We summarize our scheme into some basic steps as shown in below fig from ref[1].
Fig 3:Basic steps in VSPN(ref 1)
1.Trusted authority (TA) sets up parameters and generates anonymous (unknown) credentials.
2.Vehicle Vi’s Tamper Proof Device (TPD) starts up and request for the master secret s from RSU Rc.
3.Vehicle Vi’s TPD requests for a navigation credential from RSU Rj.
4.RSU Rj verifies Vi’s identity and sends its TPD an anonymous credential.
5.After traveling for a random distance, Vi’s TPD sends out its navigation request to RSU Rk.
6.RSU Rk transfers the navigation request to its neighbors. This process repeats until the request reaches RSU Rd covering the destination.
7.RSU Rd constructs the navigation reply message and sends it along the reverse path. Multi-hop communication takes place.
8.RSU Rk transfers rhe navigation reply message to Vi’s TPD which then verifies the message from all RSUs along the route in a batch.
9.Each RSU along the route guides Vi to reach the next RSU closer to the destination.
10.Based on Vi’s pseudo identity received from RSU Rj, TA reveal Vi’s real identity for billing purpose.
Network architecture
Fig 4: Architecture
Network is initiated by deploying the number of nodes randomly on a geographical area. Here we deployed 20 nodes in a 100X100 m^2 area. Then set a moving vehicle and it’s destination. Then find the reliable path depending upon number of hopes, energy and distance. The RSU provides the information about the shortest path of our destination. If there is a traffic in a shortest path then moves through the alternative path towards the destination then the result will be analyzed.
Applications
1. Traffic Signal: communication from the traffic light can be created with the help of VANET technology.
2. Weather conditions: for the convenience of the vehicle VANET is used to avoid traffic jam and to avoid accident by knowing all weather conditions. It helps to find the vacant parking space in all weather conditions.
3. Vision enhancement: Drivers are given a clear view of vehicles and obstacles in heavy fog conditions and can learn about the existence of vehicles hidden by the obstacles, buildings and by other vehicles
4. Driver assistance: It is mainly helpful to the drivers in driving and privacy of the driver can be preserved
5. Automatic parking: vehicles can park itself without the need for driver intervention.
6. Safety: safety applications include collision warning, information sharing, co-operative driving, other value added services like navigation, internet access etc’
7. Searching roadside locations and vehicles direction: For unknown passengers helps to find the gas stations, hotels, shopping centre etc..
8. Entertainment: It helps to passengers to play a game, use other internet applications within the vehicle.
Advantages
Public safety
Traffic management
Traffic coordination and assistance
Traveler information support
Comfort
Air pollution emission measurement and reduction.
Disadvantages
1. Flooding in route discovery initial phase
Wasted band width
Delay
Increasing network congestion
External sources for destination location
2. Bad performance for long distance between source and destination.