A Border Node Based Routing Protocol for Partially Connected Vehicular Ad Hoc Networks

Vehicular ad-hoc network (VANET) technology enables communication between vehicles, or vehicles and road-side units (RSUs) through wireless communication devices installed on the vehicles. One of the most important goals of VANETs is providing safety applications for passengers. In addition, VANETs provide comfort applications to users. Guaranteeing a reliable and stable routing protocol over VANETs is a very important step. The proposed research attempts to improve routing protocols that decrease the end-to-end delay to suit VANET communication characteristics. In addition, it proposes analysis of the end-to-end delay probability distribution. More specifically, we derive a closed-form expression for the probability distribution of the re-healing delay in a VANET conditioned on the distance between two VANET clusters. Furthermore, we propose a closed-form expression for the probability distribution of the unconditional re-healing delay. Moreover, we develop a mathematical model to calculate the probability distribution of the end-to-end delay. On the other hand, using Unmanned Aerial Vehicles (UAVs) or drones in wireless communications and Vehicular Ad-hoc Networks (VANETs) has started to attract attention. We propose a routing protocol that uses infrastructure drones for boosting VANET communications to achieve a minimum vehicle-to-drone packet delivery delay. In addition, we propose a closed-form expression for the probability distribution of the vehicle-to-drone packet delivery delay on a two-way highway. Moreover, based on that closed-form expression, we can calculate the minimum drone density (maximum separation distance between two adjacent drones) that stochastically limits the worst case of the vehicle-to-drone packet delivery delay. Furthermore, we propose a drones-active service (DAS) that is added to the location service in a VANET. This service dynamically and periodically obtains the required number of active drones based on the current highway connectivity state by obtaining the maximum distance between each two adjacent drones while satisfying a probabilistic constraint for vehicle-todrone packet delivery delay. Our analysis focuses on two-way highway VANET networks with low vehicular density. The simulation results show the accuracy of our analysis and reflect the relation between the drone density, vehicular density and speed, other VANET parameters, and the vehicle-to-drone packet delivery delay. In addition, we propose a new routing protocol called multi-copy intersection-based routing (MCIR) for vehicular ad-hoc networks (VANETs) in urban areas. MCIR is an intersectionbased routing protocol that forwards multiple copies of the packets in different road segments. Moreover, it is a beacon-less routing protocol with a carry-and-forward strategy. We show via simulation that the MCIR protocol is superior to other existing routing protocols, especially in low vehicular density scenarios. The results show that MCIR achieves a shorter end-to-end delay and a higher packet delivery ratio in urban VANET communications.

Past few decades have witnessed large increase in number of vehicles on roads due to which the traffic safety needs have also become complex and hence necessary to be taken care of. Vehicular ad hoc networks (VANETs) are becoming an asset for achieving all these goals. VANETs provide applications like driver assistance, passenger comfort and vehicle safety. Apart from its general characteristics due to the dynamic nature of road environments and traffic patterns, communication linkage among vehicles in VANETs suffers breakage problem hence requires a very reliable routing protocol. To manage the communication efficiently many routing protocols are already available for MANETs which can be further used for routing and communication among vehicles in VANETs, but characteristics of these two networks (VANET and MANET) are very different, so there is requirement to enhance these MANET routing protocols so that those can be used in VANETs. When we use some existing routing protocols in VANET then number of link breakage are surprisingly high because mobility is higher in VANETs as compared to MANETs. So this paper presents advanced version of an existing MANET routing protocol for better performance in VANET environment. The new routing protocol has removed problem of large number of routing error messages which was existing in AODV routing protocol. Protocol proposed in this paper has better results as compared to AODV and paper has also shown results of simulation and also elaborated the findings.

Intelligent Transportation Systems (ITS) is an integrated approach being developed to exchange relevant information to increase the safety and efficiency of the road transportation systems. Vehicular Ad hoc Network (VANET), a variant of mobile ad hoc networks (MANET), is a core component of ITS. Performance of this smart ITS mainly owes to the design of efficient routing protocols in VANETs. Distinct features of VANETs like unsteady connectivity, high mobility and partitioning of the network have made routing of the information in VANETs difficult and challenging, hence dictating the development of efficient routing protocols. The computation of the best route measures the performance of communication whereas routing protocols takes care of communication & routing of the data. Provision of smart communication, necessitates the analysis of routing protocols in VANET. Accordingly in this paper we have reviewed various types of existing routing protocols in VANET, listing their advantages and disadvantages. Lastly possible inclinations of forthcoming research linked to VANET routing are discussed.

Vehicular ad hoc networks (VANETs) are a new emerging recently developed advanced technology that allows a wide group of applications related to providing more safety on roads, more convenience for passengers, self-driven vehicles, and intelligent transportation systems (ITS). There are various routing protocol categories used in VANETs, like unicast, multicast, and broadcast protocols. In unicast position-based protocols, the routing decisions are based on the geographic position of the vehicles. This does not require establishment or maintenance of routes but needs location services to determine the position of the destination. Non-delay-tolerant network protocols (non-DTN), also identified as minimum delay protocols, are aimed at minimizing the delivery time of the information. Delay-tolerant protocols (DTN) are used in a variety of operating environments, including those that are subject to failures and interruptions and those with high delay, such as VANETs. This paper discusses the comparison between non-DTN and DTN routing protocols belonging to the unicast delay-tolerant position-based category. The comparison was conducted using the NS2 simulator, and the simulations of three non-DTN routing protocols and three DTN routing protocols were recorded. Simulation results show that the DTN routing protocols outperform in delivery ratio compared to the non-DTN routing protocols, but they lead to more average delay due to buffering, the processing algorithm, and priority calculation. In conclusion, non-DTN protocols are more suitable for the city environment since the distance between nodes is relatively smaller and the variations in the network topology are slower than they are on highways. On the other hand, DTN protocols are more suitable for highways due to the buffering of packets until a clear route to destination is available.

Vehicular ad hoc networks (VANETs) present an intriguing platform for several applications on e.g., intelligent transportation system (ITS) and infotainment applications aspire to be the main pattern of communication among vehicles while travelling. This can significantly impact on the amount of data exchanged by vehicles, increasing the contention on communication links and thus, degrading the quality of service of these applications. So, discrimination of data becomes imperative and forwarding critical information on suitable routes becomes decisive. Hence, a quality of service (QoS)-driven mechanism is needed to handle and assign network resources according to the stringent application data traffic demands. But, VANETs high node mobility and frequent link failure, stuck a big challenge in implementing an effective policy to meet and enforce these QoS requirements. A promising way to tackle this issue is to enforce QoS at the network layer, since it is the crucial point in VANETs’ communication. So, over the years, many QoS-aware routing protocols were specifically conceived for VANETs. In this paper, we present a comprehensive survey of QoS-aware routing protocols in VANETs’ literature. We examined the protocols based on their ability to support ITS infotainment services, their multi-constraint path problem (MCP), protocol’s functionality and weakness, objectives and design challenges. This way, we outline future directions for VANETs QoS-aware protocol research.

HyBR: A Hybrid Bio-inspired Bee swarm Routing protocol for safety applications in Vehicular Ad hoc NETworks (VANETs)

Geocast routing is one of the most investigated choices for reliable and efficient dissemination of information because of group of vehicles sharing geographic region on the road. Most of geocast routing protocols for intermittently connected Vehicular Adhoc Networks, suffer from low packet delivery, high end-to-end delay and elevated packet loss in intermittently connected networks and low throughput, high hop-to-hop disconnection, larger hop-count in fully connected networks. In this paper, guaranteed geocast routing (GGR) protocol for intermittently connected highway traffic environment has been proposed. GGR utilizes caching and heuristic function for reliable next hop vehicle selection. It also uses FAST (group of neighboring vehicles moving at higher speed than current forwarder) in packet delivery and SLOW (group of neighboring vehicles moving at lower speed than current forwarder) in hop-to-hop failure recovery. One-hop delivery has been guaranteed through acknowledgement. The proposed protocol has been simulated using NS-2 and its performance has been compared with that of adoptive carry-store forward, spray & wait and epidemic routing protocols. Results reveal that the performance of GGR is better in terms of number of routing matrices considered for both intermittently and fully connected networks.

Vehicular communication ad hoc routing protocols: A survey

Vehicular ad hoc networks (VANETs) have become a practical and valuable alternative for wide variety of novel applications in road safety, content sharing, payment at different commercial places, etc. Due to high mobility of vehicles resulting in frequent disconnections, geographic routing protocols are commonly preferred in VANETs as they do not require, route formation prior to forward as well as route maintenance. Most of the position based routing protocols adopt the greedy mode to establish the route and switch to some recovery mechanism like perimeter routing, in case of failure. However, if the probability of occurrence of perimeter mode is higher than the greedy mode, then the throughput as well as the end to end delay will be severely affected. This probability is highly influenced by many factors where in density being the major among these. In this paper, we propose a routing strategy that uses the restricted greedy forwarding by considering neighborhood vehicles having a sufficiently dense neighborhood and the least velocity variance with its own neighboring vehicles, as the next forwarder. The objective is to increase the longevity of the route and thus increasing the throughput without greatly affecting the end to end delay. The performance of the proposed approach is compared with GPSR and the simulation results are presented.

In vehicular ad hoc networks (VANETs), because of the nonexistence of end-to-end connections, it is essential that nodes take advantage of connection opportunities to forward messages to make end-to-end messaging possible. Thus, it is crucial to make sure that nodes have incentives to forward messages for others, despite the fact that the routing protocols in VANETs are different from traditional end-to-end routing protocols. In this paper, we study how to stimulate message forwarding in VANETs. Our approach is based on coalitional game theory. In particular, we propose an incentive scheme for VANETs and rigorously show that with our scheme, faithfully following the routing protocol is in the best interest of each node. In addition, we extend our scheme to taking the limited storage space of each node into consideration. Experiments on testbed trace data verify that our scheme is effective in stimulating cooperation of message forwarding in VANETs.

In vehicular ad hoc networks (VANETs), the transfer of data packets from source to destination involves the use of an efficient path search mechanism. This paper proposes such mechanism, designed in the form of firefly-swarm next hop selection algorithm with angular routing (referred to as efficient firefly routing protocol (EFR)), meant to discover a suitable route from source to destination for data packets transfer. In the proposed EFR protocol, the swarm intelligence of fireflies is deployed to find the destination node using social interaction among fireflies. In doing so, the attractiveness, brightness, position of other fireflies, neighbor’s angular position, and destination coordinates of each firefly are considered as parameters to compute its next flight toward an intermediate or destination node. Simulations are conducted to evaluate the performance of the proposed EFR protocol, showing that it outperforms the dynamic source routing (DSR) protocol in terms of throughput, packet delivery ratio, percentage of lost packet, and end-to-end delay, both under static and high mobility scenarios.

The advent of Sixth Generation (6G) wireless technologies introduces challenges and opportunities for Mobile Ad Hoc Networks (MANETs) and Vehicular Ad Hoc Networks (VANETs), necessitating a reevaluation of traditional routing protocols. This paper introduces the Multi-Metric Scoring Dynamic Source Routing (MMS-DSR), a novel enhancement of the Dynamic Source Routing (DSR) protocol, designed to meet the demands of 6G-enabled MANETs and the dynamic environments of VANETs. MMS-DSR integrates advanced technologies and methodologies to enhance routing performance in dynamic scenarios. Key among these is the use of a CNN-LSTM-based beamforming algorithm, which optimizes beamforming vectors dynamically, exploiting spatial-temporal variations characteristic of 6G channels. This enables MMS-DSR to adapt beam directions in real time based on evolving network conditions, improving link reliability and throughput. Furthermore, MMS-DSR incorporates a multi-metric scoring mechanism that evaluates routes based on multiple QoS parameters, including latency, bandwidth, and reliability, enhanced by the capabilities of Massive MIMO and the IEEE 802.11ax standard. This ensures route selection is context-aware and adaptive to changing dynamics, making it effective in urban settings where vehicular and mobile nodes coexist. Additionally, the protocol uses machine learning techniques to predict future route performance, enabling proactive adjustments in routing decisions. The integration of dynamic beamforming and machine learning allows MMS-DSR to effectively handle the high mobility and variability of 6G networks, offering a robust solution for future wireless communications, particularly in smart cities.

VANET is a new technology used for vehicular communication which aims to provide safe and secure traffic system. There are various challenges/ difficulties in VANET such as dynamic network topology, highly mobile nodes, infrastructure less network etc. which deteriorates the performance of it. Routing is a main task in any communication. Thus, numerous routing protocols have been developed which helps to improve the performance of VANET. Among these all, the position based routing protocols are reliable for many applications. Also, nowadays optimization techniques are widely used to increase the efficiency of routing protocols. In this paper implementation of a position based routing protocols like Greedy Perimeter Stateless Routing (GPSR) and Connectivity Aware Routing (CAR) is discussed. Swarm intelligence based technique which is used for optimization is ACO i.e. Ant Colony optimization. The simulation of CAR and GPSR protocols has been done with and without optimization. The performances of CAR and GPSR are evaluated and compared in terms of average packet delivery ratio, end to end delay, throughput, routing overhead, packet loss etc.. All the simulation has been done in Network Simulator 2. Results shows that ACO technique improves the performance of GPSR and CAR protocols in VANET. Also, CAR protocol shows promising results as compared to GPSR protocol.

This paper presents a novel position-based routing protocol for vehicular ad hoc networks (VANETs) to enhance traffic safety and traffic organization and facilitate driving through a smart transportation system. The protocol is referred to as the traffic flow-oriented routing (TFOR) protocol for VANETs. It considers a real-time urban scenario with multi-lane and bi-directional roads. It chooses junction optimally considering vehicular traffic flows to accomplish robust routing paths and thereby forwarding the data packets. The new junction selection mechanism and routing between the junctions is based on two-hop neighbor information, which increases packet-delivery ratio and decreases end-to-end delay. We designed, implemented, and compared TFOR against existing routing protocols of VANETs (greedy-perimeter stateless routing (GPSR), geographic source routing (GSR), and enhanced greedy traffic-aware routing (E-GyTAR)). Simulation outcomes in urban scenarios show that TFOR minimizes average end-to-end delay and routing overhead by on average 15.3% and 19.5%, respectively, compared to GPSR. It reduces routing overhead up to 17% compared to GSR. TFOR maximizes packet-delivery ratio on an average of 17.5%, 10.7%, and 7.2% compared to GPSR, GSR, and E-GyTAR, respectively.

The swift improvement of wireless communication technology has aided the creation of vehicular ad hoc networks (VANETs) as a revolutionary option for the realization of intelligent transportation systems (ITSs). VANETs facilitate seamless communication between vehicles and infrastructure (V2I) and among the vehicles themselves (V2V). These networks can enhance safety and traffic control while providing various infotainment options. To ensure stable and efficient communication in highly dynamic and quickly changing vehicular contexts, effective data packet routing is a crucial component of VANETs. This survey delves further into the VANET routing algorithms for ITS. The study aims to evaluate the effectiveness and acceptability of various routing protocols suggested for VANETs while considering their unique requirements and difficulties. The review covers ad hoc on‐demand distance vector (AODV) and dynamic source routing (DSR), as well as more current strategies designed specifically for VANETs, such as geographic routing, cluster‐based routing, and hybrid routing protocols. The review assesses the routing algorithms based on several vital parameters, including packet delivery ratio (PDR), end‐to‐end delay, throughput, network overhead, scalability, and robustness. This detailed assessment supports aspiring researchers in acquiring a better knowledge of the benefits and drawbacks of the routing algorithms currently used in VANETs.