Kavita Pandey

Hierarchical map-based location service for VANETs in urban environments

Vehicular Ad-hoc Network is gaining the attention of researchers because of the technological advancements for developing an Intelligent Transportation System (ITS). The dynamic nature of vehicles (nodes) leads to frequent path breaks and network fragmentation. Therefore, routing has become a critical issue in inter-vehicle communication. Location management in VANETs is considered as a critical issue in position based routing protocol. For this purpose we have proposed novel distributed map-based location service scheme that uses mobility pattern and density of the vehicles in the region. In the proposed location service mechanism, the geographical region is divided into segments and each segment is further fragmented into cells. For exchanging the routing information among vehicles across network, the location of destination node should be discovered within the cell. In case the destination is not discovered in the cell, the request for location search migrates to the segment. The information extracts from the digital map database helps to select location server in high traffic point regions in the entire area. The location service uses minimum speed aware policy to select location server at high traffic density waypoint and dynamic location updates are sent to location server based on threshold distance. In order to reduce the location discovery delay, adjacent level hierarchy is used for location query sent by the location servers. Simulation results obtained with different scenarios are used to demonstrate the performance of HLS, EMBL and HMLS in terms of location query answer and location update strategy. Simulation results show that HMLS achieve outperforms others in urban environments.

Distance and direction-based location aided multi-hop routing protocol for vehicular ad-hoc networks

Vehicular ad-hoc network VANET is an important technology for future development of intelligent transportation systems. Due to the highly-dynamic nature of vehicular nodes, network topology changes very frequently which complicate the routing of data packets. A number of routing protocols have been developed by various researchers. Hop count is a key parameter in evaluating the performance of a routing protocol. Number of hops required in directional routing protocols is more in comparison to other routing protocols. For a city vehicular traffic scenario we propose an improved direction-based location aided routing D-LAR protocol that we call distance and direction-based location aided routing DD-LAR protocol. A mathematical model for DD-LAR protocol has been developed to examine its performance on path duration and hop count metric. Simulations have been done in MATLAB and from the results, it can be seen that DD-LAR routing protocol shows significant performance improvement over D-LAR and LAR in terms of reducing the hop count and maximising the path duration.

Hop count analysis of location aided multihop routing protocols for VANETs

Vehicular ad-hoc network (VANET) is an important technology for future development of intelligent transportation systems. VANETs are being used as a tool for improving road safety by warning the drivers about accidents occurred ahead of them or for providing internet access to the passengers via gateways along the road. Although VANET is an application of MANETs but routing of data packets is more challenging in VANETs. This is because of frequent change in network topology due to the highly-dynamic nature of vehicular nodes. Researchers have developed various routing protocols for VANETs and hop count among others is considered as an important metric in evaluating these protocols. LAR (Location Aided Routing) and D-LAR (Directional-LAR) protocols are well known position based routing protocols for VANETs. In this paper we have proposed another protocol which is an important extension of D-LAR and which improves upon hop count in comparison to both LAR and D-LAR protocols. This protocol uses distance in addition to the directional routing strategy to select the next hop node, which results in a stable and shorter route. We have devised a generic HopCount Algorithm to compare the three protocols. Simulations are done to corroborate algorithmic analysis for multiple scenarios which depict dense environment. Performance results clearly depict that DD-LAR outperforms the other two protocols and with an increase in transmission range or vehicular density, hop count value is further reduced.

Performance analysis of routing protocols for vehicular adhoc networks using NS2/SUMO

Development of intelligent transportation system is the need of all the developing countries where urbanization and industrialization is rapidly growing. VANETs are being used as a tool for improving road safety by alarming the drivers about accidents occurred ahead of them or for providing internet access to the passengers via gateways along the road. Due to highly dynamic nature of nodes in VANETs, designing a routing protocol for VANET is quite challenging compared to MANET environment. Researchers have suggested several routing mechanism for VANETs. Few routing decision are based on topology based selection whereas others have considered different parameters like location information of nodes, traffic lights etc. As no benchmarking scheme is available for choosing a routing protocol in VANET, this article gives an insight on how to choose a routing protocol depends on varying condition of traffic. Three popular protocols AODV, DSR and LAR have been chosen for analysis on varying traffic environment. All the three protocols have been critically tested for different metrics such as Throughput, Packet Delivery Ratio and Routing overhead during the simulation. Simulation is carried out with the help of open-source simulation tools NS2, a network simulator, and SUMO, a traffic simulator.

Trust based Ad-hoc on Demand Routing protocol for MANET

Mobile Ad-hoc networks (MANET) is a set of wireless nodes without any fixed infrastructure or base station, in which nodes communicate directly to the other nodes within its transmission range over relatively bandwidth constrained wireless links. MANET is vulnerable to various types of attacks from malicious nodes due to its spontaneous nature of communication and the absence of centralized administrator. There are many attacks in MANET due to which the legitimacy of a network is compromised such as, Black Hole Attack, Worm Hole Attack, Byzantine attack, DoS attack. So, secure communication in MANET is essential and challenging task. In this paper, we present trust based Ad hoc On Demand Routing protocol for MANET. Our proposed algorithm works on the concept of honest value which is calculated on the concept of hop and trust to protect the network from malicious node. The performance of the proposed protocol is analyzed using throughput, number of drop packets, packet delivery ratio and number of received packets with the variation of number of nodes, speed and simulation time. Results show that the proposed method has better performance and enhance the security in the network.

Density Based Outlier Detection Technique

Outlier Detection has become an emerging branch of research in the field of data mining. Detecting outliers from a pattern is a popular problem. Detection of Outliers could be very beneficial, knowledgeable, interesting and useful and can be very destructive if remain unexplored. We have proposed a novel density based approach which uses a statistical measure i.e. standard deviation to identify that a data point is an outlier or not. In the current days there are large variety of different solutions has been efficiently researched. The selection of these solutions is sometimes hard as there is no one particular solution that is better than the others, but each solution is suitable under some specific type of datasets. Therefore, when choosing an outlier detection method to adapt to a new problem it is important to look on the particularities of the specific dataset that the method will be applied. To test the validity of the proposed approach, it has been applied to Wisconsin Breast Cancer dataset and Iris dataset.

REDAlert+: Medical/Fire Emergency and Warning System using Android Devices

Each year, thousands of people in developing countries die due to delayed medical response. A common complaint is that emergency vehicles respond late and when they reach the hospital, precious time is lost in understanding the patient trauma before the doctors can get to work. A large number of deaths can be prevented if medical services can be provided to the victims in time, which can happen when the emergency wing of a hospital has advance information about the trauma before the patient reaches the hospital. Most hospitals lack communication infrastructure that allows them to coordinate with emergency vehicles bringing patients to hospital. In developed countries, Vehicular Ad-hoc Networks VANETs are prevalent. These networks use vehicles as mobile nodes to create a small-interconnected network on the road. A mobile application based on the principle of VANETs in combination with wireless communication and database management has been devised, that when integrated with emergency vehicles and hospitals, provides a seamless medical response system at times of an emergency.

Throughput and delay analysis of directional‐location aided routing protocol for vehicular ad hoc networks

Summary Vehicular ad hoc networks is an integral component of intelligent transportation systems and it is an important requisite for smarter cities. Network formation and deformation among the vehicles are very frequent because of the variation in speed. Furthermore, for safety applications, messages should not face any kind of delay or collision. Therefore, establishing communication between the vehicles becomes even more challenging. Position-based routing protocols work productively in vehicular ad hoc networks. Only finding an efficient routing protocol does not solve our purport. We need to carefully examine the effect of media access control layer parameters additionally. In the event of collisions, a large number of nodes would be re-transmitting rather than sending fresh packets. A node busy in sending the retransmitted packet is called a backlog node. With an increase in the number of collisions, number of backlog nodes also increases, which affects the delay and throughput. In this article, we present the mathematical modeling of delay and throughput with IEEE 802.11 distributed coordination function (at media access control layer) for directional-location aided routing (D-LAR) position based routing protocol. For performance evaluation, simulation has been done in realistic environment created with SUMO (traffic simulator) and NS-2 (network simulator). Simulation results show the comparison between D-LAR and location aided routing (LAR) on various metrics in terms of delay, packet delivery ratio, routing overhead, throughput, and collision probability. To validate the mathematical model, analytical results has been compared with simulation results. The results confirm that performance of D-LAR is better than LAR in terms of increasing the throughput and reduction in routing overhead and delay.

N-Hop broadcast and Street Broadcast Reduction algorithm using OMNeT++ and Google Earth plugin

VANET are the systems used to collaborate the wireless devices installed on the vehicles, for transfer of messages. The implementation of algorithms on VANET in actual device is preceded by simulation of the same on a simulating environment like OMNeT++, SUMO, etc. This paper presents a study and implementation of VANET Broadcasting algorithms, and algorithms which are able to solve the problem of broadcast storming. With efficient use of resources, the transmission of signals to the different vehicles have been scalable to be broadcasted using two protocols namely, N-Hops Weighted p-persistence Broadcasting which is able to disseminate the data to different vehicles in all the regions covering the broadcast range. Another algorithm is Street Broadcast Reduction, which covers the area through different roads and effectively send the warning and alert messages to the vehicles, using the distance based schemes. The problems in VANET broadcast has been addressed, and have been implemented using OMNeT++, SUMO and Google Earth.

Reduction of congestion and signal waiting time

In this current scenario, vehicular ad-hoc networks are expected to provide support to a large range of distributed applications which ranges from traffic management, dynamic route planning to location based services. Traffic jams on the roads is a very serious issue that needs immediate attention. Various algorithms and solutions have been suggested in the field of VANETs to remove the problem of traffic congestion and waiting time. At initial level, it is not feasible to implement the proposed solution in the real world so a small area of Noida was taken up for real time simulations. The traffic simulation was created and observed using SUMO and NS2. This was in done in order to note the behavior of traffic light and congestion at the junctions and the results were further calculated and verified using AODV and GPSR protocol.