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Vehicular Ad-hoc NETworks (VANETs) have attracted a lot of attention in the research community in recent years due to their promising applications. VANETs help improve traffic safety and efficiency. Each vehicle can exchange information to inform other vehicles about the current status of the traffic flow or a dangerous situation such as an acciden...
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... inter-cluster communication protocol, once the cluster head has collected the safety messages from its cluster members, it uses a data fusion technique to combine the safety messages and then tunes to the ICC channel to forward the messages to its neighboring cluster heads. The ICD channel is assigned to one vehicle in each cluster and by using the contention-based MAC this vehicle can transmit or receive non- safety messages from other clusters. However, CBMMAC has been evaluated only for simple highway scenarios where all the vehicles are moving in the same direction. As shown in Table IV, the cluster head can only send or receive real-time traffic. Moreover, The authors have not studied the inter-cluster interference problem when two or more clusters are in close proximity or the merging collision problem. Although CBMMAC can support QoS for real-time applications while efficiently utilizing the wireless bandwidth for non real-time traffic, the use of two transceivers and one GPS system for each vehicle makes this system very expensive. munication System (CBMCS): This system has been proposed by Ding and Zeng [88] to improve road safety by reducing the number of potential accidents. Unlike the IEEE 802.11p standard, in this system the medium is divided into multiple control channels and one data channel. All the control channels use the CSMA/CA protocol, while the data channel uses TDMA/CDMA scheme to guarantee low transmission delay without collisions within each cluster. Firstly, all the vehicles tune to the control channel to form clusters. One cluster head CH is elected and each cluster member periodically sends its position and speed to its CH during its own TDMA time slot on the data channel. Then, in order to avoid inter-cluster interference, each CH selects a different orthogonal code from that of its neighboring CHs (the CDMA principle). This protocol contains a Vehicle Accident Avoidance Mechanism (VAAM) to inform close vehicles about a dangerous situation such as an accident or to warn them of some dangerous behavior. The simulation results show that the CBMCS provides an efficient channel utilization and fast access delay for safety applications, but the evaluation was limited only to safety applications and for simple highway scenarios. The authors do not describe how the multiple control channels are utilized in this protocol and it remains unclear as to whether CBMCS can handle non-safety applications. A-ADHOC [89] is based on the previous ADHOC MAC protocol. The A-ADHOC protocol is intended for real-time applications in large-scale wireless vehicular networks, offering another option of adaptive frame length. The simulation results show that A-ADHOC has surpassed the ADHOC MAC in both channel resource utilization and response time. In particular, the new protocol can avoid network failure regardless of traffic density, which is an inherent problem in the ADHOC MAC protocol. TDMA Cluster-Based MAC (TC-MAC): Almalag et al. in [9] propose a novel multi-channel MAC protocol called TDMA cluster-based MAC (TC-MAC) for VANETs. Their proposal uses a new TDMA slot reservation schedule managed by stable cluster heads. TC-MAC provides efficient time slot utilization for the participating vehicles. Unlike the IEEE 802.11p standard architecture, in TC-MAC, the frame is not divided into two intervals CCHI and SCHI. In other words, each vehicle can tune to the Control Channel (CCH) or to specific service channels (SCHs) if needed during the time cycle. A cluster formation algorithm based on the traffic flow [90], which is used in TC-MAC, was proposed in order to provide a more stable clustering architecture with less communication overhead than is caused by cluster head election and cluster maintenance procedures. During the cluster formation process, each cluster member will be assigned a local ID by its cluster head which always has a local ID 1, while ID 0 is reserved for a virtual vehicle. TC-MAC takes advantage of the local IDs that are assigned in the cluster formation algorithm. The medium access time is divided into several periodic time frames of length equal to 100 ms. Each frame is divided into N max / k time slots of fixed size τ ms, based on the data rate and the maximum packet size where N max is the maximum number of vehicles in the cluster and k is the number of slotted service channels (for the DSRC architecture, there are six service channels numbered from 0 to 5). Moreover, the time access on the control channel is also divided into periodic frames and each frame is divided into N max / k time slots. Each time slot on the CCH is divided into k mini-slots of size τ/ 6 ms used to broadcast beacons or safety messages. The main idea of the slot reservation schedule is that in each frame, each vehicle number j is allocated the time slot ( j di v k ) on the service channel number ( j mod k ) and competes for one mini- slot on the control channel during the time slot ( k di v j ) − 1 (see Fig. 19). Then vehicle j uses its mini-slot to inform the other vehicles of its transmission during j s time slot on the SCH. As an example, let N = 37 and k = 6. As shown in Fig. 20, the vehicle with local ID 22 has access to service channel ( 22 mod 6 ) = 4 during slot ( 22 di v 6 ) = 3, as well as the 5th mini-slot on the control channel in slot 3 − 1 = 2. Each new vehicle joining the cluster attempts to get the attention of the cluster head by transmitting in the mini-slot number 0 reserved for the virtual vehicle. TC-MAC has been used for intra-cluster management and safety message delivery within the cluster in which the cluster head is responsible for broadcasting safety or control messages. In addition, cluster members can use their time slots on the service channels to exchange non-safety data in unicast or multicast communication mode. Although the simulation results show that TC-MAC performs better than IEEE 802.11p, it also has some failings. This protocol was designed for simple highway traffic in which all the vehicles are moving in the same direction, and thus the collision rate will be high in bidirectional traffic and urban scenarios due to the merging collision problem. This approach is intensely dependent on the local IDs delivered by the cluster heads in each cluster. Each cluster head should periodically update the table of the cluster members and their local IDs and then send this information to all cluster members, which increases the overhead. It is clear that one of the main benefits of using a clustering technique in TC-MAC is the efficient utilization of all 7 channels within one group without access collisions. However, it is not clear from the paper, in which period of time the cluster formation and cluster maintenance take place. Moreover, high collision levels when two or many clusters are in close proximity are caused by the inter-cluster interference problem. Since each time slot on the control channel is divided into six mini-slots, the throughput on each service channel is six times higher than on the control channel, which shows that TC-MAC has been designed to provide a high transmission rate for non-safety messages; this inevitably has a significant consequence for safety applications. works: Bharati and Zhuang propose in [91], [92] a Cooperative ADHOC MAC protocol, with the aim of improving throughput for non-safety applications. The scheduling mechanism developed by the CAH-MAC protocol is based on distributed TDMA similar to the one in ADHOC MAC in that the channel access time is divided into periodic frames and each frame is further divided into time slots. The goal of the research work is to propose a new way to overcome the transmission failure problem when it occurs due to poor channel conditions. In fact, upon detecting a transmission failure between the transmitter and the receiver, a neighboring node called a “helper node” offers cooperation to relay the packet that failed to reach the destination during an idle time slot. Compared to the ADHOC MAC protocol, the main disadvantage of CAH-MAC is that the use of any free time slots by the helper nodes for cooperative relay transmissions can lead to the access collision problem with the vehicles that attempt to obtain an available time slot. tions (CBT): Sheu and Lin [93] have proposed and evaluated a Cluster-Based TDMA system (CBT) for inter-vehicle communications. The goal of this system is to develop contention-free intra-cluster and inter-cluster communications while minimizing collisions when two or more clusters are approaching each other. The protocol uses a simple transmit-and-listen scheme to quickly elect a VANET Coordinator VC. The CBT system assumes that each vehicle is equipped with a GPS positioning system and synchronization between the vehicles can be performed by using GPS timing information. The access time is divided into frames and each frame consists of n time slots. As shown in Fig. 21(a), the slot 0 in frame 1 (SYN) is used by neighboring vehicles to exchange an 8 byte beacon signal to indicate the start of a frame. However, the same slot serves in other frames which are used by the elected VANET Coordinator VC to broadcast a Slot-Allocation Map (SAM) to its VANET Nodes VNs. The slot 1 to slot n − 1 in the first frame are used for VC election (VC-elected stage), while the slot 1 to slot n 1 in the other frames (Slot-allocation stage) are used by their designated vehicles to send data messages. Intra- and inter-cluster communications are based on the exchange of a MAC-layer frame shown in Fig. 21(b). Each frame consists of three fields: an 8 byte beacon field is used to synchronize the start of the next slot and allows the VC to detect the existence of a neighboring VC , two SAMs of size ( m − 8 − 4 )/ 2 bytes and guard band field of 4 bytes. The transmit-and-listen scheme has been developed to randomly elect a VC among all the VNs. VC is the vehicle that transmits a CFV message ...
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Latency is an important metric for time-critical safety applications in vehicular ad-hoc networks (VANETs). Medium access control (MAC) protocol can be greatly exploited to achieve low latency. In this paper, we modify the existing VeMAC protocol frame structure to enhance its latency aspects for time-critical applications. We introduce additional...
![Figure 2. Frame structure of VeMAC protocol [15].](profile/Saleem-Raza/publication/331523515/figure/fig2/AS:733041949433857@1551782228393/Frame-structure-of-VeMAC-protocol-15_Q320.jpg)
Transmission of time-critical messages in accident situations is of paramount importance for safety applications in VANET. These messages always require very low latency, which is an important metric for these applications. In particular, they impose real-time requirements. The MAC layer is an important place to satisfy multitude of performance met...
Abstract In support of traffic safety applications, vehicular networks should offer a robust Medium Access Control (MAC) layer protocol that can provide a reliable delivery service to safety-related messages. As the safety applications generally use broadcasting to propagate their messages, a reliable broadcast protocol is essential. In general, ho...
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... These messages were defined in SAE J2735 [8] and they facilitate Basic Safety Message (BSM) functional redundancy, i.e., communicating the BSM-relevant data on any service channel. In addition, these messages can be used along with the BSMs in a dual and triple redundancy scheme. ...
... A solution for VANET based on coefficient of correlation that is activity accordant for Between periods of error and therefore the correct of reception times, Hamieh projected [8]. The method solely depend upon reactive electronic jamming attacked and the transmitter transmits solely once sensing legitimate space activity that The approach is barely uses the Error chance like a metric, that isn't enough to incorporate electronic jamming [10] and the Jamming electronic in platoons is addressed on [11], The method alone rely on reactive ECM attacked and the transmitter transmits alone once sensing legitimate area activity that The approach is barely uses the Error likelihood sort of a metric, that may not enough to include ECM [12]. ...
... Remember that each On-Board Unit (OBU) sends out a Basic Safety Message (BSM) every 100 ms using the safety channel (CH172). This results in a broadcast frequency of 10 BSM/s as referenced in sources [9] and [8]]. Building on this, we're looking into the idea of redundancy by amplifying this message frequency. ...
Intelligent Transportation Systems (ITS) encompasses technologies, services, and applications facilitating communication between vehicles (V2V) and between vehicles and fixed infrastructure (V2I and I2V). This mutual interaction constitutes a Vehicular Ad-Hoc Network (VANET) which supports a plethora of applications targeting critical transportation aspects, such as safety, mobility, and environmental considerations. Dedicated Short Range Communications (DSRC), operating on the 5.9 GHz band, is pivotal for such exchanges. We introduced an innovative algorithm designed to identify jamming attacks and transition the Safety Application to a secure fail-safe mode. This algorithm leverages a dual-metric strategy, incorporating both distance and PDR measurements. Field tests confirm that our algorithm adeptly recognizes the activities of deceptive jammers, ensuring a prompt shift of the safety application into its fail-safe state. This paper delves into these countermeasures, evaluating their efficiency via mathematical modeling, simulations, and on-ground testing. Findings acknowledge that these strategies bolster the reliability of safety applications in jamming scenarios. Furthermore, the approaches propounded align with ongoing standardization endeavors by relevant authorities, ensuring communication mediums remain unhindered.
... Contention issues arise with N2N and C2C communications. Only deterministic MAC protocols are eligible, such as TDMA, synchronous CDMA, and CSMA-DCR (deterministic collision resolution) [15], [16]. Such protocols (that are out-of-scope) must meet a number of requirements, notably timeliness (worst-case access delays have upper bounds, in the order of 20-30 ms [17]) and immunity to cyberattacks (attacks on MAC protocols should be detected instantly). ...
Safety, privacy, efficiency and cybersecurity (SPEC) properties are mandatory in vehicular networks. Owing to intrinsic limitations, the V2X framework and related communicating autonomous vehicles are inadequate. We explore the CMX framework (Coordinated Mobility for X = SPEC), Next Generation Vehicles (NGVs), and protocols for safety-critical inter-vehicle communications and agreements that solve problems left open in the V2X framework. Then, we focus on cyberattacks and physical attacks against isolated NGVs and cohorts of NGVs. The cyberphysical security analysis investigates more than 20 attacks and demonstrates that the goal set for CMX is verified. In the presence of attacks, safety is never compromised, possibly at the expense of diminished efficiency.
... For this reason, among others, Intelligent Transportation Systems have been established as smart technological solutions to improve road safety and promote smart mobility [1]. ITS offers several benefits including smart traffic management and monitoring, enhanced safety services, user-oriented mobility services, etc. [2]. Moreover, they rely on a connected infrastructure via inter-vehicle (V2V) and infrastructure (V2I) communication links interconnecting road sensors, road users, and vehicles. ...
In Intelligent Transportation Systems (ITS), ensuring road safety has paved the way for innovative advancements such as autonomous driving. These self-driving vehicles, with their variety of sensors, harness the potential to minimize human driving errors and enhance transportation efficiency via sophisticated AI modules. However, the reliability of these sensors remains challenging, especially as they can be vulnerable to anomalies resulting from adverse weather, technical issues, and cyber-attacks. Such inconsistencies can lead to imprecise or erroneous navigation decisions for autonomous vehicles that can result in fatal consequences, e.g., failure in recognizing obstacles. This survey delivers a comprehensive review of the latest research on solutions for detecting anomalies in sensor data. After laying the foundation on the workings of the connected and autonomous vehicles, we categorize anomaly detection methods into three groups: statistical, classical machine learning, and deep learning techniques. We provide a qualitative assessment of these methods to underline existing research limitations. We conclude by spotlighting key research questions to enhance the dependability of autonomous driving in forthcoming studies.
... This approach implies using alternative messages, namely the À la Carte (ACM) and Probe Vehicle Data (PVD) to deliver safety related data using redundant channels. These messages were defined in SAE J2735 [8] and they facilitate Basic Safety Message (BSM) functional redundancy, i.e., communicating the BSM-relevant data on any service channel. In addition, these messages can be used along with the BSMs in a dual and triple redundancy scheme. ...
... A solution for VANET based on coefficient of correlation that is activity accordant for Between periods of error and therefore the correct of reception times, Hamieh projected [8]. The method solely depend upon reactive electronic jamming attacked and the transmitter transmits solely once sensing legitimate space activity that The approach is barely uses the Error chance like a metric, that isn't enough to incorporate electronic jamming [10] and the Jamming electronic in platoons is addressed on [11], The method alone rely on reactive ECM attacked and the transmitter transmits 3 alone once sensing legitimate area activity that The approach is barely uses the Error likelihood sort of a metric, that may not enough to include ECM [12]. ...
... Remember that each On-Board Unit (OBU) sends out a Basic Safety Message (BSM) every 100 ms using the safety channel (CH172). This results in a broadcast frequency of 10 BSM/s as referenced in sources [9] and [8]]. Building on this, we're looking into the idea of redundancy by amplifying this message frequency. ...
Intelligent Transportation Systems (ITS) encompasses technologies, services, and applications facilitating communication between vehicles (V2V) and between vehicles and fixed infrastructure (V2I and I2V). This mutual interaction constitutes a Vehicular Ad-Hoc Network (VANET) which supports a plethora of applications targeting critical transportation aspects, such as safety, mo-bility, and environmental considerations. Dedicated Short Range Communications (DSRC), op-erating on the 5.9 GHz band, is pivotal for such exchanges. We introduced an innovative algorithm designed to identify jamming attacks and transition the Safety Application to a secure fail-safe mode. This algorithm leverages a dual-metric strategy, incorporating both distance and PDR measurements. Field tests confirm that our algorithm adeptly recognizes the activities of deceptive jammers, ensuring a prompt shift of the safety application into its fail-safe state. This paper delves into these countermeasures, evaluating their efficiency via mathematical modelling, simulations, and on-ground testing. Findings acknowledge that these strategies bolster the reliability of safety applications in jamming scenarios. Furthermore, the approaches propounded align with ongoing standardization endeavours by relevant authorities, ensuring communication mediums remain unhindered.
... In the vehicular AD hoc network, vehicles need to periodically exchange status information and safety information. However, characteristics such as excessive Vehicle speed, frequent network topology changes and no center [1] result in unreliable data transmission between vehicles (Vehicle to Vehicle (V2V) and between vehicles to Roadside Unit (V2R) in vehicle networking. Therefore, reliable and effective Medium Access Control (MAC) protocol is the focus of research. ...
The aim of MAC protocol research without RSU is to solve some of the challenges and problems that exist in VANETs without RSU support. For example, Rsus cannot be deployed in certain regions or scenarios due to various reasons (such as cost, lack of infrastructure, etc.). In this case, the MAC protocol without RSU assistance provides a solution that does not rely on RSU for communication. In addition, in traditional VANETs, the RSU acts as an important relay node, helping vehicles communicate with each other. However, without a sufficiently dense RSU deployment, network coverage will be limited. Through the MAC protocol without RSU assistance, vehicles can communicate directly, expanding the coverage of the network. Through the MAC protocol without RSU assistance, vehicles can communicate directly, expanding the coverage of the network. Improve the reliability and throughput of VANETs networks: Due to the mobility of vehicles and the uncertainty of the communication environment, problems such as message collisions and data transmission delays are common in VANETs. By designing an effective MAC protocol without RSU assistance, message collision can be reduced, system throughput can be improved, and network reliability can be enhanced. Finally, in some application scenarios, such as vehicle safety and traffic management, real-time communication is very important. Without the support of RSU, traditional VANETs may suffer from large communication delays. By studying the MAC protocol without RSU assistance, the communication delay can be minimized to meet the needs of real-time communication.
... The authors from the publication mentioned above later produced another paper [15] that examines various arrangements utilizing similar traffic conditions as above and simulation platforms, by changing the sensing window, probability of resource reselection P, and the power that is being transmitted and afterward evaluation of Packet Delivery Ratio across the distance between the transmitter and receiver. They concluded that: expanding P diminishes the PDR in circumstances with channel load, even though the contrasts between various estimations of P are not that prominent to the channel load; adjusting the normal 1s window size for sensing to incremental range (so that later detecting estimations are given higher loads in the determination procedure) delivers some improvement, even though the additions are practically nothing; channels that have lesser load will have a negligible effect on changing the force edge, however, PDR is increased by a lower force limit on a channel having high priority; if the channel has lesser load, the transmitting capacity reduces PDR and seems to have an immaterial impact on channels with more load; lastly, the list to select resources from (that is twenty percent of the total resources, as indicated in Release 14) shows no noteworthy effect too. ...
... Resource reservation interval (RRI) defines that range. For example, if RRI is 20 ms, the range would be in [25,75], if RRI is 50 ms, the range would be in [10,30] and if RRI is 100 ms or above, the range would be in [5,15]. These ranges are opportunities for the transmission of a resource. ...
Sensing-based Semi-Persistent Scheduling (SB-SPS) MAC protocol is proposed as part of the latest cellular vehicle to everything (C-V2X) standard for medium access between vehicles. As C-V2X uses LTE based frame structure, mode 4 of the C-V2X standard uses SB-SPS to allocate resource blocks effectively. C-V2X shows great potential for the future as it brings many improvements such as enhanced range, reliability, and the ability to support and evolve with emerging technologies such as 5G. In this article, the SB-SPS protocol’s performance was analyzed in different scenarios using OMNET++, SUMO, and Veins simulator. Different vehicle speeds and densities were used to observe the effect on packet loss and throughput. It was found that as packet loss decreased, throughput increased when the mobility of vehicles decreased. The effects of changing some important parameters of SB-SPS were also observed. The results showed that while parameters such as increasing the number of subchannels increased the packet delivery ratio (PDR), the change in the probability of resource reselection parameter did not affect the PDR.
... Due to the tremendous growth of wireless communication, sensing, automatic control technology, and mobile computing, vehicular ad hoc network (VANET) has developed. VANET is widely utilized for maximizing traffic safety and improving traffic efficacy [1]. VANET is a peculiar ad-hoc network containing many dynamic nodes that leave out the centralized control equipment. ...
Vehicular ad hoc networks (VANETs) establish the connection between the vehicles through wireless communication. This link stability is significant for achieving traffic safety and traffic efficiencies. But sharing security messages in the mobile environment is very complex because of the excessive speed of the vehicles, unsteady communication links, and geographically constrained topologies. A Roadside Unit is vital for vehicle connection with the transportation center. We proposed Tri-Parametric FUZZY logic (TP-FUZZY) for establishing the stable connection in VANET. The proposed Tri-Parametric FUZZY Logic effectively addresses the complexity of the vehicles’ excessive speed, etc. We have considered the combination of normal-speed vehicles containing a high data rate and the shortest distance for forming the clusters. The cluster head (CH) concept is implemented to monitor and control the entire mechanism. The FUZZY Logic executes the automatic selection of the next CH if the current CH triggers exit from the cluster. It ensures the overall cluster mechanisms stability. The proposed simulation results prove that Tri-Parametric FUZZY logic performance in the aspect of Packet delivery ratio, Dynamic cluster head changes, Routing overhead, End to end delay and Energy consumption is more effective than the other existing mechanisms. Thus, the proposed TP-FUZZY is a prominent solution for establishing reliable link connectivity in the VANET.
... These are challenging to design because VANETs are faced with a fast-changing topology and have to provide reliable and periodic local broadcasts of safety messages to neighbouring vehicles. To address reliability and periodic transmissions, distributed TDMA-like MAC protocols have received some attention [110][111][112]. The majority of the work, however, has focused on the properties of IEEE 802.11p, as it is a part of the DSRC protocol stack. ...
Infrastructure‐less networks connect communication devices end‐to‐end by managing links and routes independent of fixed networking facilities, relying on dedicated protocols running on end‐user devices. The large variety of infrastructure‐less concepts and related aspects can be confusing both for beginning Ph.D. students as well as experienced researchers who wish to get an overview of neighbouring areas to their own research foci. Frequently discussed topics such as different types of sensor‐, vehicular‐, or opportunistic networks are covered. The authors describe different networking concepts by looking at aspects such as the main properties, common applications, and ongoing research. Furthermore, the concepts by common characteristics such as node mobility, network density, or power consumption are compared. The authors also discuss network performance evaluation by describing commonly used metrics, different evaluation techniques, and software tools for simulation‐based evaluation. The references given in each section help obtain in‐depth information about the presented topics and give hints about open research questions, which can be a starting point for own investigations.
... In order to tackle the high energy consumption issue that occurs by constantly listening for incoming data, we propose a synchronized version of ESP-NOW which allows EDs to be in receive mode only for short and predefined periods of time while they remain in deep sleep mode for the rest of the time. This is a typical approach followed by known protocols and approaches in the literature in order to have the receivers ready when there is such a need [10,11,12]. In the proposed approach, the EDs wake up periodically to synchronize with the master device and receive data. ...
ESP-NOW is a peer-to-peer wireless communication protocol developed by Espressif Systems for low-power and low-cost in-situ Internet of Things devices. ESP-NOW supports bidirectional communication between multiple transmitters (mas-ters) and multiple end-devices (slaves). It also supports both unicast and broadcast transmissions. This paper proposes a synchronized method, called Sync-ESP-NOW, to improve the energy efficiency of the end-devices by scheduling broadcast transmissions in predefined time intervals. The proposed method creates a synchronized application layer which allows the end-devices to be in on mode only when a master's transmission is performed, while they remain in sleep mode to conserve energy for the rest of the time. However, due to the periodic wake-up of the end-devices, a compromise in terms of delay exists. We evaluate the proposed approach through a series of experiments and demonstrate significant improvements in terms of energy efficiency at the end-devices without compromising the packet reception ratio. The proposed approach achieves an up to 96% lower energy consumption considering various packet rate scenarios.
... The slotted ppersistence technique can therefore result in a lengthy wait before rebroadcasting in a sparse network when no cars are present in the prior slots. On the other hand, in a congested network, several vehicles will attempt to rebroadcast concurrently in the same slot, leading to data traffic congestion [41][42][43]. ...
This paper investigates the effectiveness of using P-persistent carrier sensing multiple access (P-Persistent CSMA) on vehicular connectivity as vehicles dynamically form temporary communication networks using simulation and mathematical modelling. In the connected and autonomous environment, effective and efficient connectivity between vehicles (V2V) and between vehicles and infrastructure (V2I) is critical. The simulation was performed in MATLAB and included the investigation of the effect of vehicular density, probability value change, and increase in Backoff time, and change in data frame size. The results showed that as vehicular density, probability, and data frame size increased, throughput decreased as data traffic increased, whereas as Backoff time and probability increased, throughput increased. Furthermore, as data size increases with decreasing probability level, channel utilization improves. Based on these findings and the derived mathematical expressions, a proposed dynamic and adaptive model is presented, allowing for maximum throughput while minimizing collisions. This is accomplished by equating four mathematical expressions and substituting them using iteration to achieve a balanced and optimal level of communication channel utilization by dynamically adjusting the three main parameters under consideration as a function of increasing vehicular density (P-Persistent probability level, Backoff time, and data frame length). To achieve such dynamical and adaptive optimization, four mathematical expressions are used. The resulting model is promising and will improve the efficiency of non-adaptive conventional P-Persistent CSMA. The presented work proved to increase the effectiveness of the conventional p-persistent technique using a multi-dimensional parameter correlation, which is more effective than weighted, slotted, or adaptive P-Persistent approaches.
