66 research outputs found
Previous hop routing: exploiting opportunism in VANETs
Routing in highly dynamic wireless networks such as Vehicular Ad-hoc Networks
(VANETs) is a challenging task due to frequent topology changes. Sustaining
a transmission path between peers in such network environment is difficult. In
this thesis, Previous Hop Routing (PHR) is poposed; an opportunistic forwarding
protocol exploiting previous hop information and distance to destination to
make the forwarding decision on a packet-by-packet basis. It is intended for use in
highly dynamic network where the life time of a hop-by-hop path between source
and destination nodes is short. Exploiting the broadcast nature of wireless communication
avoids the need to copy packets, and enables redundant paths to be
formed. To save network resources, especially under high network loads, PHR
employs probabilistic forwarding. The forwarding probability is calculated based
on the perceived network load as measured by the arrival rate at the network
interface. We evaluate PHR in an urban VANET environment using NS2 (for
network traffic) and SUMO (for vehicular movement) simulators, with scenarios
configured to re
ect real-world conditions. The simulation scenarios are configured
to use two velocity profiles i.e. Low and high velocity. The results show that the
PHR networks able to achieve best performance as measured by Packet Delivery
Ratio (PDR) and Drop Burst Length (DBL) compared to conventional routing
protocols in high velocity scenarios
Drop-burst length evaluation of urban VANETs
Networks performance is traditionally evaluated using packet delivery ratio (PDR) and latency (delay).We propose an addition mechanism the drop-burst length (DBL). Many traffic classes display varying application-level performance according to the pattern of drops, even if the PDR is similar. In this paper we study a number of VANET scenarios and evaluate them with
these three metrics. Vehicular Ad-hoc Networks (VANETs) are an emerging class of Mobile Ad-hoc Network (MANETs) where nodes include both moving vehicles and fixed infrastructure. VANETs aim to make transportation systems more intelligent by sharing information to improve safety and comfort. Efficient and adaptive routing
protocols are essential for achieving reliable and scalable network performance. However, routing in VANETs is challenging due to the frequent, high-speed movement of vehicles, which results in
frequent network topology changes. Our simulations are carried out using NS2 (for network traffic) and SUMO (for vehicular movement) simulators, with scenarios configured to reflect real-world conditions. The results show that OLSR is able to achieve a best DBL performance and
demonstrates higher PDR performance comparing to AODV and GPSR under low network load. However, with GPSR, the network shows more stable PDR under medium and high network load. In term of delay OLSR is outperformed by GPSR
A Framework for Performance Evaluation of VANETs Using NS-3 Simulator
During the last decade, the number of vehicles on roads has been rapidly growing. Therefore, the demands for communication on the move are also increasing and the attention from many researchers is focused on the Vehicular Ad hoc NETworks (VANETs) because of their importance for Intelligent Transportation Systems (ITSs). Due to the complexity and cost of practical evaluation of VANETs, the researchers often rely on network simulation in order to evaluate their work. In this paper, we have developed a Network Simulator 3 (NS-3) based framework for VANETs that provides network performance analysis based on the key performance indicators such as throughput, packet loss ratio, overhead, end-to-end delay, jitter, etc. Since VANETs are highly dynamic networks, many researchers have proposed different routing protocols in order to improve the network performance. In this paper we have compared several topology-based routing protocols, and proposed utilization of the commonly used Expected Transmission Count (ETX) metric to improve VANET performance.</p
A topology-oblivious routing protocol for NDN-VANETs
Vehicular Ad Hoc Networks (VANETs) are characterized by intermittent
connectivity, which leads to failures of end-to-end paths between nodes. Named
Data Networking (NDN) is a network paradigm that deals with such problems,
since information is forwarded based on content and not on the location of the
hosts. In this work, we propose an enhanced routing protocol of our previous
topology-oblivious Multihop, Multipath, and Multichannel NDN for VANETs
(MMM-VNDN) routing strategy that exploits several paths to achieve more
efficient content retrieval. Our new enhanced protocol, i mproved MMM-VNDN
(iMMM-VNDN), creates paths between a requester node and a provider by
broadcasting Interest messages. When a provider responds with a Data message to
a broadcast Interest message, we create unicast routes between nodes, by using
the MAC address(es) as the distinct address(es) of each node. iMMM-VNDN
extracts and thus creates routes based on the MAC addresses from the strategy
layer of an NDN node. Simulation results show that our routing strategy
performs better than other state of the art strategies in terms of Interest
Satisfaction Rate, while keeping the latency and jitter of messages low
Energy and Time Efficient Routing Protocols for High throughout VANET
Vehicular Ad-Hoc networks (VANETS) has received significant attention in current years, thanks to its distinctive characteristics, that square measure totally different from Mobile Ad-Hoc networks(MANETS), like speedy topology modification, frequent link failure, and high vehicle quality. The most disadvantage of VANETS system is that the network instability, that vintages to reduce the network potency. During this article we have a tendency to suggest two algorithms: CBLTRprotocol and IDVR protocol. The CBLTR protocol aims to extend the route stability and average throughput in a very biface phase situation. The Cluster Heads (CHs) square measure chosen supported most Life-Time (LT) among all vehicles that square measure set at intervals every cluster. The IDVR protocol aims to extend the route stability and average throughput, and to scale back end-to-end delay in a very grid topology. The electoral Intersection CH (ICH) receives a collection of CandidateShortest Routes (SCSR) closed to the required destination from the Software Outlined Network (SDN). The IDVR protocol picks the best route supported its destination location, present location, and the most of the minimum average output of SCSR. We have a tendency to used grappling traffic generator simulators and MATLAB to guage the performance of our proposed protocols. These protocols considerably trounce many protocols mentioned within the literature, in terms of the many parameters
Evaluation of MANET Routing Protocols in Realistic Environments
Projecte final de carrera realitzat en col.laboraciĂł amb College of Electronics and Information Engineering. Tongji UniversityRecently, many researchers have become interested in MANET (Mobile Ad-hoc NET-
works) to construct a self-con gurable network without existing communication infras-
tructure. This research presents the results of a detailed performance evaluation on
several MANET routing protocols working under realistic environments. The routing
protocols, mobility models and other aspects are explained and discussed in order to
know how to use them properly to model real-life conditions. NS-2 and Bonnmotion
were used to create the networks, services and environment characteristics in general.
It is concluded which protocols can handle which applications and which not and
that the performance of the protocols can be considerably di erent when more and
more realistic elements are taken into account. This should be considered in further
researches since the nowadays evolution of MANET will bring them soon into services
of our society
Energy and Mobility Models based Performance Evaluation in MANET
Mobile ad hoc networks are constituted with randomly moving nodes and movement of these nodes is depended upon moving model used in the network. Performance of the network directly depends on the movements and energy consumed in a specific time period by the nodes. Also performance of the protocol used for communication depends on the type of mobility model used by that specific protocol. In this paper, performance of AODV (Ad hoc On demand Distance Vector) routing protocol have been evaluated in respect of five mobility models Random Way Point Mobility Model, Manhattan Grid Mobility Model, Gauss Markov Mobility Model, Random Direction Mobility Model, RPGM (Reference Point Group Mobility)). Performance metrics are considered as: average energy consumption and average residual energy. By varying the network connections, speed of the nodes, and node densities, in different scenarios, routing protocol has been simulated in network simulator 2. Simulation results show that reference point group mobility model is best suitable model as compared to other mobility models for AODV protocol in terms of energy consumption
Recent Developments on Mobile Ad-Hoc Networks and Vehicular Ad-Hoc Networks
This book presents collective works published in the recent Special Issue (SI) entitled "Recent Developments on Mobile Ad-Hoc Networks and Vehicular Ad-Hoc Networks”. These works expose the readership to the latest solutions and techniques for MANETs and VANETs. They cover interesting topics such as power-aware optimization solutions for MANETs, data dissemination in VANETs, adaptive multi-hop broadcast schemes for VANETs, multi-metric routing protocols for VANETs, and incentive mechanisms to encourage the distribution of information in VANETs. The book demonstrates pioneering work in these fields, investigates novel solutions and methods, and discusses future trends in these field
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