Message Transmission Delay Research Articles

Seamless Connectivity with Fuzzy-Based Unmanned Aerial Vehicle for VANET in Congested Zone

Providing seamless connectivity during transit in vehicular ad hoc networks (VANETs) is the most promising and challenging task. In VANET, the vehicles are able to communicate with other vehicles and also with the infrastructure units such as road side unit (RSU). The coverage range of RSU is not sufficient to cover the whole road. The vehicle can drive to an area which is not covered by any of the RSUs, and it is termed as congested zone (CZ). This will extremely lead to traffic congestion and maximize blocking probability. In order to provide connectivity between the road segments and to avoid long delay in message transmission, unmanned aerial vehicles (UAVs) are placed in CZs, which act as relay nodes. To enhance the connectivity of the vehicles, a fuzzy-based UAV-assisted handoff scheme (F-UAV-HO) is proposed in this work. By adopting fuzzy, the unwanted participation of UAV is limited in non-congested traffic, thereby saving the battery resource. To validate the proposed work, the simulations are executed in Network Simulator 2.35. The proposed system outperforms other conventional UAV-assisted schemes in congested traffic in terms of average end-to-end delay, PDR and throughput.

Evaluating the Performance of ETSI-ITS Multi-Stack Protocols for V2V Communication in VANETs: A Simulation Study

The research evaluates various multi-stack protocols for Vehicular Ad-hoc Networks (VANETs), focusing on Vehicle-to-Vehicle (V2V) communication scenarios with Emergency Vehicle (EV) simulations. The study uses the ns-3 network and SUMO (Simulation of Urban MObility) traffic simulators to test these protocols in diverse scenarios, including fluctuating data rates and dense network conditions. By implementing the IEEE 802.11p protocol alongside vehicular message dissemination stacks compliant with ETSI (European Telecommunications Standards Institute) ITS (Intelligent Transport Systems) standards, the study performs simulation experiments with varying vehicle counts, ranging from 20 to 35. It employs two distinct data rate configurations while maintaining a constant transmission power of 23 dBm. The results indicate a decline in the average Packet Reception Ratio (PRR) as vehicle density increases, indicating heightened contention and interference. At the same time, there is an observed increase in average latency, contributing to increased message transmission and reception delays. The quantitative analysis demonstrates an inverse relationship between the average PRR and the total vehicle count when the SEND_CAM message is enabled. On the other hand, disabling SEND_CAM maintains a relatively consistent average PRR across scenarios. Additionally, a positive correlation between vehicle count and average latency underlines the impact of network congestion and interference on communication efficacy within VANETs. Despite suboptimal PRR values falling between 41% and 47%, latency performance remains satisfactory, with average latency durations ranging from 0.154 s to 0.187 s. Notably, the SEND_CAM parameter status shows negligible impact on protocol performance, suggesting that network density plays a more pivotal role. Finally, this study offers valuable insights into the trade-offs and challenges of multi-stack protocols in V2V communication within VANETs. Further optimization efforts are recommended to improve packet reception ratios, especially in high-vehicle-density environments, while maintaining acceptable latency levels. These findings contribute to the ongoing efforts to enhance the reliability and efficiency of communication protocols in VANETs, thus advancing the development of intelligent transportation systems. The study's quantitative protocol performance analysis under varying network conditions provides valuable guidance for optimizing V2V communication deployments in VANETs.

Clustered DTN routing based on sensing node relationship strength

AbstractDelay tolerant networks (DTNs) is a network evolved from mobile networks. Differing from the traditional network, which has a stable end‐to‐end transmission path, DTNs are sparse and intermittently connected mobile ad hoc network, which are widely used in harsh environments, such as battlefields, seabed, space communication networks, and so on. In DTNs, intermittent connectivity, partitioned network, long delays and node mobility characteristics make the network fail to communicate frequently, therefore, how to successfully forward the message is of extreme importance. Up to now, almost all the traditional models in DTNs use the store‐carry‐forward method. This paper proposes a novel clustered DTN routing model based on sensing node relationship strength. The routing mechanism takes advantage of the number of other nodes encountered by the nodes in the process of movement and the changes in the number of nodes to calculate the strength of the relationship between nodes, and clusters DTN routing according to the strength of the relationship between nodes. Moreover, the relationship between nodes in a cluster and other clusters is used to transmit messages between clusters, and messages are transmitted within clusters according to the strength of the relationship between nodes. Simulation results show that the routing mechanism not only increases the success rate of message transmission, but also reduces the transmission delay of messages and improves network performance.

Optimizing Message Response Time in IoT Security Using DenseNet and Fusion Techniques for Enhanced Real-Time Threat Detection

As IoT devices increase, accuracy and data security become increasingly crucial. This research recommends a powerful threat detection system that accelerates message responses to improve IoT security. The recommended strategy finds dangers in using many data sources. Our deep learning system is DenseNet. It groups photographs nicely. We show how the approach works using real-world experiments. It has few false positives and negatives and is effective at recognizing items. Through ablation research, we examine how design and component selections impact technique performance. This clarifies the method's fundamentals. The research reveals that feature selection, fusion, and DenseNet design improve the technique. We discuss the need for fine-tuning hyperparameters to improve approaches and monitor more individuals. The strategy makes IoT communities safer and more robust by laying the groundwork for threat detection and response. This approach solves message transmission delay concerns, making the IoT safer. These discoveries may benefit hacking specialists. They improve and speed up IoT security.

Gradual Route Modification in Mobile Wireless Multihop Network with Combination of Carrying and Forwarding

In a wireless multihop network, data messages are transmitted along a wireless multihop transmission route composed of a sequence of intermediate wireless nodes forwarding the data messages. However, it is difficult to detect a wireless multihop transmission route from a source wireless node to a destination one if a wireless nodes are not evenly distributed and there are some areas in which wireless nodes are sparsely distributed. Some methods have been proposed to solve this problem by combination of forwarding data messages between neighbor intermediate wireless nodes as in a usual wireless multihop network and carrying data messages to pass through such areas. In the conventional methods with the combination of forwarding and carrying data messages, some dedicated intermediate mobile wireless nodes serve the role of carrying. Hence, such nodes are required to consume more battery power which results in lower connectivity of the network. In addition, transmissions of data messages might be suspended for waiting the carrying intermediate wireless nodes which results in longer end-to-end transmission delay. In order to solve the problems, this paper proposes a novel carrying and forwarding method which gradually modifies a wireless multihop transmission route to evenly share the required mobility overhead among all the intermediate mobile wireless nodes and to reduce end-to-end transmission delay of data messages by making the route shorter. The proposed method ensures that no successive intermediate wireless nodes pass each other without neighboring.

A Clustering-Based Routing Protocol Using Path Pattern Discovery Method to Minimize Delay in VANET

In vehicular ad hoc networks (VANETs), vehicle-to-vehicle (V2V) communications can link vehicles to each other, and vehicle-to-infrastructure (V2I) messaging and communications can link roadside infrastructure such as routers. The vehicles in these networks act as relays that transmit critical messages in the network. Due to the high-speed movement of vehicles on the road, real-time messaging and minimizing the delay in sending messages is one of the most important objectives of VANET developers. On the other hand, the high mobility of vehicles causes communication interruptions and decreases the data delivery rate in VANET. To overcome this issue, predicting the path of vehicles can play an important role in sending data from the source to the destination. When an accident occurs on the road, the messages that are sensed by the imbedded sensors in the vehicles need to be sent, and if they are sent by the vehicles that change their route, these messages will not be sent to the destination and the performance of the network will be disturbed. Previous methods in the literature for data transmission in intervehicular networks have focused more on reliability and trust, and little attention has been paid to the prediction of vehicle movement paths in these types of networks. Therefore, for fast and reliable data transmission in VANET, accurate prediction of vehicle movement and creation of movement patterns can be effective in message transmission delay and data delivery rate. In this paper, we present an approach using a combination of cluster-based routing protocols and pattern discovery methods to minimize latency in VANETs. The outline of the proposed method has four modules: primary data collection and analysis, primary data preparation and analysis, pattern extraction and vehicle route discovery, and vehicle clustering and data/information transmission routing. The simulation results show that the proposed method with a delivery rate of 88.56% has significantly improved compared to the previous methods in terms of package delivery rate. Also, the proposed method with a total delay of 24.566 ms has a shorter delay than the previous methods in terms of message sending delay in the network.

Provable Secure and Lightweight Vehicle Message Broadcasting Authentication Protocol with Privacy Protection for VANETs

With the emergence of intelligent transportation and the widespread use of vehicle network equipment, the vehicle ad hoc network (VANET) is widely used in the communication among participating entities to obtain traffic information, such as speed, traffic congestion, road conditions, and accident. In VANET, the secure and efficient message broadcasting protocol can effectively reduce the message transmission delay, to meet the requirements of openness, real-time, and high-speed mobility in the VANET environment. However, most related researches mainly rely on third parties, such as TA and RSU, to ensure the identity authentication of vehicles and the security of message transmission, which are not suitable for infrastructure-less scenario. Therefore, designing a protocol for decentralized message broadcasting, identity authentication without a third party, and the safe message transmission is meaningful. In this study, we propose a lightweight vehicle message broadcasting authentication protocol, which realizes the identity authentication of the message broadcasting vehicle and vehicle-to-vehicle (V2V) key agreement without the need of a trusted third party. In our protocol, the vehicle can verify the identity of the sending vehicle to identify the reliability of the message source and prevent malicious messages. Meanwhile, the vehicle can update its pseudonym identity to resist tracking attacks, but the trusted authority can always track the real identity of the malicious message sending vehicle according to the sent messages. The proposed protocol is proved secure by formal security proof. In addition, our scheme provides better security and computational efficiency over others by comparing with related schemes.

Approbation of the stochastic group virus protection model

The article discusses the implementation in Java of the stochastic collaborative virus defense model developed within the framework of the Distributed Object-Based Stochastic Hybrid Systems (DOBSHS) model and its analysis. The goal of the work is to test the model in conditions close to the real world on the way to introducing its use in the practical environment. We propose a method of translating a system specification in the SHYMaude language, intended for the specification and analysis of DOBSHS models in the rewriting logic framework, into the corresponding Java implementation. The resulting Java system is deployed on virtual machines, the virus and the group virus alert system are modeled stochastically. To analyze the system we use several metrics, such as the saturation time of the virus propagation, the proportion of infected nodes upon reaching saturation and the maximal virus propagation speed. We use Monte Carlo method with the computation of confidence intervals to obtain estimates of the selected metrics. We perform analysis on the basis of the sigmoid virus propagation graph over time in the presence of the defense system. We implemented two versions of the system using two protocols for transmitting messages between nodes, TCP/IP and UDP. We measured the influence of the protocol type and the associated costs on the defense system effectiveness. To assess the potential of cost reduction associated with the use of different message transmission protocols, we performed analysis of the original DOBSHS model modified to model message transmission delays. We measured the influence of other model parameters important for the next steps towards the practical use of the model. To address the system scalability, we propose a hierarchical approach to the system design to make possible its use with a large number of nodes.

Data Transmission in SAGIN with FANET/MANET of Drones

The purpose of this article is to simulate data transmission and calculate traffic parameters in SAGIN air segment for which Ad Hoc network of flying drones is considered as a model. Traffic modeling is based on the manet-routing-compare example from the ns3 simulator library, which has been supplemented with code to calculate packet loss, throughput, and message transmission delays. The program allowed considering drones movement at both low and high speeds from 3.6 km/h to 72 km/h. The dependences of traffic losses on data transmission power, transaction sizes and data transmission speed are obtained and analyzed. The distribution of the average effective arrival rate λ and the throughput/goodput for drones has been studied. Comparing traffic characteristics in models with different numbers of drones allows to judge how the required quality of service can be achieved by choosing the right transmission parameters.

A methodology for the evaluation of the message transmission delay over IEC 61850 communication network — a real-time HV/MV substation case study

The growing intelligence of the nowadays distribution grids is due to the integration of Information and Communication Technologies (ICTs). Such a development is converting the traditional grid into the smart grid concept. Communicating over a reliable ICT infrastructure, distributed Intelligent Electronic Devices (IEDs) perform supervision, protection, and control of the smart grid. The communication network is not errorless, and any error of the underlying communication network can degrade the power grid performance or even cause instability in it. Hence, there is a necessity to obtain a modeling method to analyze its Quality of Service (QoS). One of the most important quality measures of the Substation Communication Network (SCN) traffic is the message transmission delay. Thus, this paper proposes a methodology to evaluate the message transmission delay through an analytical model. To estimate the transmission delay, a port connection model represents the message distribution model. Then a traffic-flow-source model, and a traffic-flow-service model are applied to characterize each flow while it is served through different ports. Finally, delay is calculated based on the corresponding flow and service information. The estimation model is applied on an IEC-61850-MMS (Manufacturing Message Specification)-based communication scenario for a load-shedding goal that is considered over a real reduced-scale HV/MV smart substation test bench. The estimated results are compared to the measured values by the Wireshark network analyzer that indicates an estimation error of less than 10%.

The Optimization of Classroom Teaching in Colleges and Universities Based on Network Topology

In order to improve the teaching effect of programming courses, this article applies network topology to the construction of programming course teaching platform system and constructs a teaching framework combined with intelligent teaching mode. In addition, this article takes the opportunistic social network composed of mobile smart terminal devices as the application background and briefly introduces the concept, characteristics, and application scenarios of the opportunistic social network. In addition, the typical message forwarding algorithm currently studied in this paper is analyzed. Taking into account the social attributes and forwarding willingness of nodes, in order to increase the message transmission rate and reduce message transmission delay and network overhead, two message transmission strategies are proposed to improve the operating effect of the programming course teaching platform. Finally, this paper verifies the effectiveness of the network topology in the teaching of the algorithm and programming of the intelligent teaching mode through experimental research.

Signal power and energy-per-bit optimization problems in systems mMTC

Introduction: Currently, the issues of Internet of Things technology are being actively studied. The operation of a large number of various self-powered sensors is within the framework of a massive machine-type communication scenario, using random access methods. Topical issues in this type of communication are how to reduce the transmission signal power and to increase the device lifetime by reducing the consumed energy per bit. Purpose: Formulation and analysis of the problems of minimizing the transmission power and consumed energy per bit in systems with or without retransmissions in order to obtain the achievability bounds. Results: A model of the system is described, within which four problems are formulated and described, concerning the signal power minimization and energy consumption for given parameters (the number of information bits, the spectral efficiency of the system, and the Packet Delivery Ratio). The numerical results of solving these optimization problems are presented. They make it possible to obtain the achievability bounds for the considered characteristics in systems with or without losses. The lower bounds obtained by the Shannon formula are also presented, assuming that the message length is not limited. The obtained results showed that solving the minimization problem with respect to one of the parameters (signal power or consumed energy per bit) does not minimize the second parameter. This difference is most significant for information messages of a small length, which is common in IoT scenarios. Practical relevance: The results obtained allow you to assess the potential for minimizing the transmission signal power and consumed energy per bit in random multiple access systems with massive machine-type communication scenarios. Discussion: The presented problems were solved without taking into account the average delay of message transmission; the introduction of such a limitation should increase the transmitted signal power and consumed energy per bit.

Formal Guarantees of Timely Progress for Distributed Knowledge Propagation

Autonomous air traffic management (ATM) operations for urban air mobility (UAM) will necessitate the use of distributed protocols for decentralized coordination between aircraft. As UAM operations are time-critical, it will be imperative to have formal guarantees of progress for the distributed protocols used in ATM. Under asynchronous settings, message transmission and processing delays are unbounded, making it impossible to provide deterministic bounds on the time required to make progress. We present an approach for formally guaranteeing timely progress in a Two-Phase Acknowledge distributed knowledge propagation protocol by probabilistically modeling the delays using theories of the Multicopy Two-Hop Relay protocol and the M/M/1 queue system. The guarantee states a probabilistic upper bound to the time for progress as a function of the probabilities of the total transmission and processing delays being less than two given values. We also showcase the development of a library of formal theories, that is tailored towards reasoning about timely progress in distributed protocols deployed in airborne networks, in the Athena proof assistant.

Joint design of control policy and network scheduling policy for wireless networked control systems: Theory and application

In this paper, we study a wireless networked control system (WNCS) with N⩾2 sub-systems sharing a common wireless channel. Each sub-system consists of a plant and a controller and the control message must be delivered from the controller to the plant through the shared wireless channel. The wireless channel is unreliable due to shadowing and fading. As a result, a packet can be successfully delivered in a slot with a certain probability. A network scheduling policy determines how to transmit those control messages generated by such N sub-systems and directly influences the transmission delay of control messages. We first consider the case that all sub-systems have the same sampling period. We characterize the stability condition of such a WNCS under the joint design of the control policy and the network scheduling policy by means of 2N linear inequalities. For scalar systems, we further simplify the stability condition into only one linear inequality for two special cases: the perfect-channel case and the symmetric-structure case. One main technical contribution of this paper is to introduce the recent results on the network scheduling policy design for delay-constrained wireless communications into the analysis of WNCSs. In addition, we have applied our theory to a practical problem of stabilizing multiple pendulum-cart sub-systems over a shared wireless channel. Simulations show that our joint design effectively achieves better performance than existing baseline.

Adaptive Fractional-Order Operator Clock Synchronization Algorithm Based on Grey Prediction

As a result of the influence of clock drift and uncertainty delay in synchronous message transmission, the clock synchronization model based on statistical distribution cannot accurately describe clock deviation. This model also requires a large number of timestamp samples that cause a storage occupation issue for wireless sensor nodes with limited resources. The modeling method based on grey prediction has advantages of low sample demand and simple modeling process. However, the accuracy of the existing clock synchronization models needs to be improved. Based on the grey prediction theory, this paper proposes an adaptive fractional-order operator clock synchronization algorithm considering uncertainty delay. First, based on the clock model and clock offset model, the frequency offset between nodes is optimized by taking the mean on the clock frequencies. Second, a grey prediction algorithm based on a fractional-order operator is proposed by estimating the uncertainty delay in message transmission to obtain the clock offset. Finally, the order of the fractional-order accumulation is adjusted adaptively in the grey prediction model according to the collected timestamp sample values so that the estimation of the uncertainty delay is more accurate, thereby improving the accuracy of the clock offset. Compared with the first-order accumulative grey prediction clock synchronization algorithms and timing-sync protocol for sensor networks, the proposed scheme improved the synchronization accuracy by 29.18% and 44.01%, respectively, and reduced the variance of the clock offset by 48.66% and 64.89%. Thus, the proposed algorithm is characterized by improved stability.

A scheme of D2D-based delay analysis and vehicle relay algorithm in VANET

The D2D-based VANET (Vehicular Ad-hoc Network) makes up for the defects of the traditional IEEE 802.11p network, and has the advantages of low latency and high throughput. In order to reduce the delay of message transmission between vehicles, a D2D-based hybrid V2I/V2V (Vehicle-to-Infrastructure/Vehicle-to-Vehicle) IoV (Internet of Vehicle) architecture was considered, which firstly clusters vehicles on the road according to motion consistency. The message is transmitted between the clusters, and in addition to being transmitted through the RSU (Road Side Unit), it can also be relayed by establishing a D2D link between the vehicles. Based on the SINR (Signal to Interference plus Noise Ratio) and the minimum capacity constraint, the optimal transmission path is selected by predicting the delay of each cellular link and D2D link to reduce the end-to-end delay. In addition, for accurate modeling and analysis, a three-step method is used to predict and compare end-to-end delays. The simulation proves that this relay algorithm significantly reduces the delay compared with other methods.

Lion optimization algorithm (LOA)-based reliable emergency message broadcasting system in VANET

In vehicular ad hoc network (VANET), the standard topology changes caused by the fast mobility of nodes create many challenges to the efficient data delivery in vehicular environment. The density-, mobility- and location-based dissemination technique can fulfill the needs of emergency message broadcasting. Emergency message broadcasting in both highway and urban scenarios has so many problems such as high reliability, low latency and scalability that remains unsolved. The road structure, message redundancy, channel contention are the major issues in urban scenarios. Usually, broadcast protocols for VANET use beacon messages, which is disseminated among the vehicles, in order to get neighborhood information. When the vehicles are next to each other trying to broadcast at the same time, this may lead to frequent contention and broadcast storms. On the other hand, in sparse density scenarios, vehicles have to face with failures in the message delivery. In our research, an adaptive scheduled partitioning and broadcasting technique (ASPBT) will be introduced for a reliable and efficient emergency message broadcasting. This protocol dynamically adjusts the number of partitions and beacon periodicity to reduce the number of retransmissions. In our proposed technique, partition sizes are determined using network density, and the transmission schedule for each partition is estimated using lion optimization algorithm (LOA). It is an optimization biologically inspired by the characteristics of lions. Its corporate and solitary behaviors such as prey capturing, roaming, mating and defense are helped to identify the optimal partition to broadcast the emergency messages first. To lower emergency message transmission delay and reduce message redundancy, ASPBT includes a novel forwarding node selection scheme that utilizes optimal partition, mini-slot and black burst to quickly select remote neighboring nodes, and a single forwarding node is successfully chosen by the asynchronous contention among them. Then, bidirectional broadcast, multi-directional broadcast and directional broadcast are designed according to the positions of the emergency message senders. ASPBT will work well in different network densities and both highway and urban scenarios. Our solid analytical evaluation and simulation results indicate that our proposed technique outperforms the existing broadcasting schemes in VANET in terms of efficiency, delay and reliability.

An Improved Routing Algorithm for Mobile Opportunistic Networks using a Genetic Approach

Background/Objectives: Nowadays, Mobile Opportunistic Networks (MONs) are counted as one of the most interesting development of MANETs. In MONs, forwarding messages through mobile nodes is a big challenging research problem. Methods/Analysis: In this study, an optimization technique that based on a Genetic Algorithm (GA) is proposed. It is oriented towards solving most issues faced in Delay/Disruption Tolerant Network (DTN) routing such as there is no end to end connectivity between nodes, long delay for transmission message in path, congestion during sending the message and more. Findings: The proposed technique outperforms the other state-of-art methods regarding to delivery ratio, message transmission delay and message overhead ratio. Application/Improvements: Compared to the state-of art methods, the results show that our proposed algorithm has a better performance in terms of message delivery ratio and message transmission delay, and message overhead ratio.

Separation of a Mixture of Three-Parameter Lognormal Distributions in the Analysis of Communication Environments

Methods for the separation of a mixture of three-parameter lognormal distributions are investigated theoretically and empirically in the context of modeling message transmission delays in a computer cluster communication environment. Delay modeling based on mixtures of three-parameter lognormal distributions is proposed and parameter estimation methods for such models are investigated. Identifiability of the given family of distributions is proved, which is a necessary condition for the mixture separation problem to be well-posed. The proposed problem-oriented modifications of the standard algorithms are shown to be superior to the traditional methods.

Design of embedded inter-board communication middleware based on LCM

Aiming at the distributed architecture of embedded computer system, the network communication middleware is designed based on Lightweight Communication and Marshalling (LCM). In order to improve the reliability and performance of inter-board message interaction, middleware realizes the bidirectional named pipeline, message publication confirmation mechanism, subscription message multithreading processing mode and other improved design schemes, and provides the standardized programming interface while inheriting the topic of “publish-subscribe” based on LCM. Finally, the message transmission delay design was tested on the hardware (Loongson 2K1000 processor) and software (VxWorks operating system) platform. The results show that the message transmission delay is very close to that of traditional UDP by using LCM-based embedded inter-board network communication middleware.