Vehicular Ad Hoc Network (VANET) is a form of Mobile Ad Hoc
Networks, but the nodes of this network are vehicles with special equipment to enable
them to communicate with each other. These networks need to implement protocols to
ensure that messag
es are reached to their destinations and achieve the desired goal of the
application.
In this paper, we present an analysis of the performance of a number of major routing
protocols used in these networks which protocols AODV (Ad hoc On-Demand Distance
Vector), DSR (Dynamic Source Routing), and OLSR (Optimized link state routing). This
analysis is based on various parameters such as packet delivery ratio and end-to-end delay,
in order to find the best protocol can be used in the network with low density.
To achieve this purpose, we used a simulator OPNET_17.5. Depending on the
simulation results we have obtained and the analysis and comparison of these protocols at
different low density contract .We found that the protocol AODV is the best among the
studied protocols under the conditions set out in this study.
A Vehicular Ad-hoc Network (VANET) is a collection of nodes forming a
wireless network, but the nodes of this network are vehicles with special equipment that
enable them to communicate with each other. VANET protocols have to face high
challenges
due to dynamically changing topologies, link breakage and low vehicular
density. A suitable and effective routing protocol helps to ensure that messages are reached
to their destinations and achieve the desired aim of the application.
In this research, we present an analysis of the performance of two major routing
protocols used in these networks, which are AODV (Ad hoc On-Demand Distance Vector)
and GPSR (Greedy Perimeter Stateless Routing). This analysis is based on various
parameters such as end-to-end delay and average dropped packets, in order to find the best
protocol which can be used in the network with low density at the junctions. To achieve
this purpose, we used a simulator OPNET_17.5. Depending on the simulation results, we
have obtained and the analysis and comparison of two protocols at different low density
contract. We found that GPSR protocol has better performance end-to-end delay and
average dropped packets are used as the performance metrics, and is better for VANET
under the low vehicular density simulation scenario at junctions.
A Vehicular Ad-hoc Network (VANET) is a group of vehicles, which have special
equipments enable them to connect with each other as a wireless network .The attacks are
considered as the most serious challenge against this network, especially those t
argeting
availability requirement, which is one of the most important security requirements in
VANET. The Denial of Service (DoS) and Distributed Denial of Service (DDoS) attacks
are the most important attacks since they make the network not available for actual users.
In this research, we present an algorithm to detect and face the DDoS attack. This
algorithm depends on a black list contains the IDs for malicious vehicles, which are being
chosen depending on a certain threshold value for a number of messages received from
them. We analyze the algorithm performance depending on throughput, packet delivery
ratio, end to end delay parameters, and compare it with the performance of the Queue
Limiting Algorithm (QLA) .To achieve this purpose, we use NS2.35 simulator using
details to support Wireless Access in Vehicular Environments (WAVE). The simulation
results showed that the proposed algorithm reduces the effect of the attack Significantly
since it increases the throughput and packet delivery ratio.
