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Performance comparison of AODV and OLSR in VANETs urban environments under realistic mobility patterns
Abstract and Figures
A Vehicular Ad Hoc Network (VANET) is an in-stance of MANETs that establishes wireless connections between cars. In VANETs, routing protocols and other techniques must be adapted to vehicular-specific capabilities and requirements. As many previous works have shown, routing performance is greatly dependent to the availability and stability of wireless links, which makes it a crucial parameter that should not be neglected in order to obtain accurate performance measurements in VANETs. Although routing protocols have already been analyzed and compared in the past, simulations and comparisons have almost always been done considering random motions. But could we assess that those results hold if performed using realistic urban vehicular motion patterns ? In this paper, we evaluate AODV and OLSR performance in realistic urban scenarios. We study those protocols under varying metrics such as node mobility and vehicle density, and with varying traffic rates. We show that clustering effects created by cars aggregating at intersections have remarkable impacts on evaluation and performance metrics. Our objective is to provide a qualitative assessment of the applicability of the protocols in different vehicular scenarios.
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... MANET Network. An ad hoc network is one in which devices such as computers and cell phones communicate with each other using wireless devices [1][2][3][4][5][6][7]. In the MANET network, nodes (laptops, mobile phones, and other wireless devices) can move freely and completely randomly as the topology changes frequently [7][8][9][10][11][12][13][14]. ...
... An ad hoc network is one in which devices such as computers and cell phones communicate with each other using wireless devices [1][2][3][4][5][6][7]. In the MANET network, nodes (laptops, mobile phones, and other wireless devices) can move freely and completely randomly as the topology changes frequently [7][8][9][10][11][12][13][14]. Each node can act as a client and receive information or as a server that sends the provided data over the network. ...
The main challenge of the MANET network is the continuous management of information, each device, to ensure the correct direction of traffic. MANET consists of a peer-to-peer connection; the network is self-repairing and at the same time self-formed. The network can be used in the field of road safety, in sensors in the home, healthcare, robotics, etc. The aim of this work was to study the MANET network and its protocols and especially the AODV protocol, the choice of peer in the AODV protocol, and the subsequent improvement of this mechanism. The work deals with ETX metrics and its subsequent implementation in the AODV protocol. The work includes simulations of the AODV protocol and subsequently also simulations of the AODV-ETX protocol. The implementation of the proposed result simulation takes place in Network Simulator 3 tool. The work contains a comparison of the AODV and AODV-ETX protocols. The simulation results are shown in tables and plotted. The AODV-ETX has better properties compared to the AODV protocol, but with a larger number of nodes over 20, these properties approach the AODV protocol. The packet loss, packet delay, and permeability are considered for performance evaluations.
... Motivation. The Optimized Link State Routing (OLSR) protocol deemed as the best to deploy in VANET compared to other simulated protocols [3,4]. In OLSR, vehicles (nodes) exchange and collect Hello messages with their neighbors. ...
... Existing works have studied the performance of different protocols where the topologybased Optimized Link State Routing (OLSR) Protocol [30] have demonstrated superior performance in urban VANET compared to Ad-hoc On-demand Distance Vector (AODV) in terms of end-to-end delay and an average number of hops [3]. In addition, OLSR outperforms AODV, and Greedy Perimeter Stateless Routing (GPSR) protocols because of its shorter delay, path length, and routing overhead [4]. ...
In this paper, a blockchain-enabled Stackelberg game model is proposed for the Quality-of-Service Optimized Link State Routing (QoS-OLSR) protocol in urban VANET. While QoS-OLSR protocols introduce game models, Stackelberg in specific, to select stable relays, the information exchanged by nodes and the selection process cannot be trusted. The introduction of Blockchain to VANET arose as a means for adding trust. However, existing works integrating blockchain do not fully exploit its capabilities in hosting verified reputations, selecting relays, or sharing monetary incentives to motivate cooperation of relays. Therefore, the proposed Stackelberg game model integrates off-chain QoS-OLSR protocol and designed on-chain smart contracts, which consists of two managers: Node Reputation Manager (NRM) and Relay Selection Game Manager (RSGM) to select relays. The proposed game model has three stages: 1) the role identification, 2) the off-chain follower incentive selection, and 3) the on-chain leader profit maximization. The first stage is for nodes identify their role in the game model; leader or follower. Then, the second stage allows followers (nodes) to calculate incentives for leaders (relays) based on off-chain exchanged QoS-OLSR messages including QoS and reputation. NRM allows verifying the reputations within the messages of nodes. The calculated incentives are deposited to RSGM as followers’ strategies. The third stage, executed on-chain in RSGM, generates the set of accepted followers for a leader reliably and forwards the deposited incentives to leaders. Simulations were conducted to demonstrate that the proposed game model outperforms in terms of leaders’ utility and followers’ payments while keeping the percentage of relays constant compared to the benchmark model. Furthermore, cost analysis confirms the feasibility and cost-efficiency of such a model.
... VANET is a practical application of mobile ad hoc network (MANET) in transportation systems [20]. [15] has assessed the performance of AODV & OLSR for VANET in urban environment. The study clearly reflected that OLSR is better for that scenario. ...
Vehicular Ad-hoc network (VANETs) is a type of ad hoc network which has faced many challenges for its implementation such as Technical issues which include are Large Size area, Routing, Security, Congestion, High Mobility, Limited road topology, Intermitted connectivity, Continuous power transmission for significant computing communication & sensing of the network & On road issues include narrow road, unstructured road, all roads are not allowed for all vehicles, busy road, no defined speed on road, no road maintenance, high frequency of accidents, poor sign board, no road side amenities, multiple numbers of toll booths etc. In order to enhance the performance of the desired real time network link between the nodes must be stable and reliable so that information can be transmitted reliably to the desired destination. This paper has experimentally studied the optimal path for different routing protocols in VANETs. This paper clearly concludes which routing protocol is better under different parameters such as number of hops, average hop count, total packet send and received for the realistic environment.
This paper tackles the problem of the propagation of charging information in Vehicular Ad-hoc Networks (VANETs) and the decentralized allocation of Vehicle-to-Vehicle (V2V) charging pairs. Electric Vehicles (EVs) have gained the attention of various sectors as a green alternative to the air-polluting fuel-based vehicles. However, due to the limitation of the EVs' battery capacity and the shortage in the number of charging stations causing significant waiting time to charge, V2V charging has emerged as a promising solution to help address these issues. Mainly, V2V solutions need to define two mechanisms: an information dissemination mechanism and a charging pairs allocation mechanism. In the literature, two architectures are proposed: centralized and semi-distributed using VANET. However, in addition to suffering from the single point of failure problem, centralized solutions consider only connected vehicles during the charging pair allocation. On the other hand, existing VANET based solutions address the problem of charging information dissemination while still performing the allocation of V2V charging pairs in a centralized way. In this paper, we propose an ad-hoc-based solution for V2V charging where both information dissemination and charging pairs allocation are performed over VANET. To do so, at the application layer of VANET, a decentralized protocol for V2V is proposed. This protocol is divided into two phases: providers announcement where consumers in the network can discover the nearby providers, and providers-consumers allocation where providers select the appropriate consumer based on the received OFFERs (Table 5). At the network layer, Quality of Service-Optimized Link State Routing (QoS-OLSR) is used to find routing paths using the Multi-Point Relays (MPRs). These MPRs are in fact utilized by the protocol to propagate the announcement of the providers to the network. The simulation results show high performance of the proposed protocol in terms of packet delivery ratio and end-to-end delay. In addition, in terms of payoff and allocation rate, the proposed protocol performs better than centralized allocation in the presence of disconnected EVs.
A Mobile Ad Hoc Network (MANET) is much more vulnerable to various security attacks due to its high mobility, multi-hop communication and the absence of centralized administration. In this paper, we investigate the impact of Jellyfish periodic dropping attack on MANETs under different routing protocols. This investigate is under the class of denial-of-service attack and targets closed loop flows which results in delay and data loss. In this paper, the simulation results are gathered using OPNET network simulator and its effect on network performance is studied by analysing re-transmission attempts, network load and throughput. The results have shown that the impact of Jellyfish periodic dropping attack which reduces the network performance. Performance shows OLSR performs better than AODV under periodic drop attack.
This paper tackles the problem of improving the coalitions' stability for Quality of Service Optimized Link State Routing (QoS-OLSR) protocol in urban Vehicular Ad-hoc Networks (VANETs). VANETs have introduced communication among vehicles for the Intelligent Transportation System (ITS) allowing several safety and user-oriented applications to be implemented in an ad-hoc manner. The routing protocols in VANET play a significant role in the delivery of data packets for such applications. However, the rapid changes in the topology of urban-VANET affect the relative stability among moving vehicles and consequently cause a high drop in the network performance. Several works considered urban metrics and game theory models for stable relay selection and cluster formation where the stability of a relay is measured compared to all the neighbor vehicles rather than selection based on relative stability between a vehicle and its relay. In addition, some works proposed matching theory that focuses on the individual preferences of players, to introduce stability. Alternatively, the Hedonic game considers preferences and enhances stability through joining coalitions to improve the overall utility of all participating members in each coalition. Therefore, in this paper, we propose a two-phase Hedonic game model that improves the coalitions' stability for QoS-OLSR in urban-VANET by considering the urban characteristics such as traffic lights, intersections, and lanes' directions. Players play the game in an ad-hoc manner by exchanging a set of messages and join coalitions that include relatively more stable members. Hence, the relative stability among coalition members is the utility of the coalition. A coalition utility depends on the urban characteristics which affect several metrics such as the time to leave the street and the probability of the direction to leave the nearest intersection. Simulations, that are conducted using SUMO and NS3, show high network performance in terms of packet delivery ratio, throughput, and end-to-end delay compared to benchmark protocols.
In this paper, we consider the LoRa technology to expand sensor network coverage in smart sustainable cities. A model of a LoRa mesh network is proposed using the AODV protocol in packet routing. With a simulation model developed based on OMNET++, a series of computer experiments was carried out with changing various parameters. In the experiments results, the end-to-end delay and packet loss ratio were analyzed in the dependence on the number of nodes and packet size in the network. The simulation results show that the latency is relatively high in the LoRa mesh network, but it might be accepted for some applications.
Nowadays, the low-power long-range networks are required for the Internet of Things applications, in which devices can transmit data over long distances and consume low energy. Low-Power Wide-Area Networks (LPWANs) have emerged to focus on a group of networks providing solutions for long-range communication and saving power consumption. However, most such networks rely on star topology networks, where the end nodes send data directly to the gateway, which leads to an issue when many nodes are far from the gateway. Aiming for no need for additional gateways, we consider multi-hop communication in LPWANs in this paper. Routing protocols are used to help some nodes that can become relay nodes and find the optimal route to forward the data to the gateway. In the simulated LoRa network, we evaluated the routing protocols in considering the delivery latency and packet loss ratio in varying the network size and number of nodes. Also, the results bring an insight into the future design of a multi-hop communication supported in LPWANs.
This document describes the Optimized Link State Routing (OLSR)
protocol for mobile ad hoc networks. The protocol is an optimization
of the classical link state algorithm tailored to the requirements of
a mobile wireless LAN. The key concept used in the protocol is that
of multipoint relays (MPRs). MPRs are selected nodes which forward
broadcast messages during the flooding process. This technique
substantially reduces the message overhead as compared to a classical
flooding mechanism, where every node retransmits each message when it
receives the first copy of the message. In OLSR, link state
information is generated only by nodes elected as MPRs. Thus, a
second optimization is achieved by minimizing the number of control
messages flooded in the network. As a third optimization, an MPR
node may chose to report only links between itself and its MPR
selectors. Hence, as contrary to the classic link state algorithm,
partial link state information is distributed in the network. This
information is then used for route calculation. OLSR provides
optimal routes (in terms of number of hops). The protocol is
particularly suitable for large and dense networks as the technique
of MPRs works well in this context.
Modelling of acceleration and deceleration distances and times associated with speed change cycles under normal driving conditions is essential for the analysis of operating cost, fuel consumption and pollutant emissions, as well as for determining geometric, stopped and queuing components of overall delay. Similarly, modelling of acceleration and deceleration characteristics of individual vehicles is a key issue in relation to the accuracy of microsimulation models. This paper describes the acceleration and deceleration models used in the aaSIDRA software for intersection analysis, and emphasises the research needs for better model calibration considering different vehicle types, specific traffic facilities, different traffic demand levels, different road types, and a wide range of initial and final speeds.
Kurzfassung Wir stellen mit dem Intelligent-Driver Model (IDM) ein Mikromodell vor, welches realitäts-getreue Simulationseigenschaften mit Einfachheit verbindet. Seine robuste Dynamik so-wie die deterministische und kontinuierliche Abhängigkeit der Beschleunigung von lokalen Einflussgrößen ermöglicht einen Einsatz als Regler in einem Fahrerassistenzsystem. Seine sechs Longitudinalparameter sind alle anschaulich und erlauben eine einfache Modellierung verschiedener Fahrstile und fahrzeugtyp-spezifischer Eigenschaften, variabler Straßen-und Lichtverhältnisse sowie eine Simulation von Linien-Beeinflussungen. Mit Erweiterungen ist auch der menschliche Fahrer modellierbar. Das IDM wird durch ein allgemein formuliertes Spurwechselmodell ergänzt, welches mit beliebigen Longitudinalmodellen zusammenarbeit und hier erstmals ausführlich vorge-stellt wird. Wie das IDM hat es Parameter, die direkt den Fahrstil beschreiben. Wir zeigen anhand von Simulationen tatsächlicher Verkehrssituationen, dass das IDM sowohl die beobachtete kollektive Dynamik der Verkehrszusammenbrüche als auch das Longitudinalverhalten einzelner Fahrzeuge (Stichwort Fahrerassistenzsysteme) realistisch wiedergeben kann.
Vehicular multi-hop ad hoc networks (VANETs) enable the exchange of information between vehicles without any fixed infrastructure. The application range of such networks may cover safety related applications like the warning of drivers about accidents or congestions as well as Internet access e.g. via gateways along the road. The varying conditions in VANETs introduce high requirements on the routing protocols being used. Thus, we developed a realistic freeway mobility model and evaluated the performance of AODV, DSR, FSR and TORA in typical freeway traffic scenarios on the basis network simulations. The results show that AODV performs best in most of the simulated traffic situations, followed by FSR and DSR, while TORA is inapplicable for VANETs.
One of the most important methods for evaluating the characteristics of ad hoc networking protocols is through the use of simulation. Simulation provides researchers with a number of significant benefits, including repeatable scenarios, isolation of parameters, and exploration of a variety of metrics. The topology and movement of the nodes in the simulation are key factors in the performance of the network protocol under study. Once the nodes have been initially distributed, the mobility model dictates the movement of the nodes within the network. Because the mobility of the nodes directly impacts the performance of the protocols, simulation results obtained with unrealistic movement models may not correctly reflect the true performance of the protocols. The majority of existing mobility models for ad hoc networks do not provide realistic movement scenarios; they are limited to random walk models without any obstacles. In this paper, we propose to create more realistic movement models through the incorporation of obstacles. These obstacles are utilized to both restrict node movement as well as wireless transmissions. In addition to the inclusion of obstacles, we construct movement paths using the Voronoi diagram of obstacle vertices. Nodes can then be randomly distributed across the paths, and can use shortest path route computations to destinations at randomly chosen obstacles. Simulation results show that the use of obstacles and pathways has a significant impact on the performance of ad hoc network protocols.
In this paper, we describe the Optimized Link State Routing Protocol (OLSR) [19],[20], a proactive routing protocol for Mobile Ad-hoc NETworks (MANETs). We evaluate its performance through exhaustive simulations using the Network Simulator 2 (ns2) [1], and compare with other ad-hoc protocols, specifically the Ad-hoc On-Demand Distance Vector (AODV) [4] routing protocol and the Dynamic Source Routing (DSR) [5] protocol. We study the protocols under varying conditions (node mobility, network density) and with varying traffic (TCP, UDP, different number of connections/streams) to provide a qualitative assessment of the applicability of the protocols in different scenarios.
Vehicular ad hoc network (VANET) is an emerging new class of mobile ad hoc networks, which can be used to improve road safety and comfort of the passengers inside vehicles. Due to mobility constraints and high dynamics, routing is a more challenging task in VANETs. In this work, we evaluate the performance of the conventional ad hoc routing protocols in vehicular network environment. The objective of this study is to assess the applicability of these protocols in different vehicular scenarios. Two location-based and two topology-based ad hoc routing protocols are evaluated in city and highway scenarios. Mobility model has significant effects on the simulation results. Conventional mobility models are unsuitable for VANET simulations. We used intelligent driver model based tool VanetMobiSim to generate realistic mobility traces. Performance metrics such as packet delivery ratio, normalised routing load, end-to-end delay, and throughput are evaluated using NS2.