scholarly journals Time Slot Utilization for Efficient Multi-Channel MAC Protocol in VANETs

Sensors ◽  
2018 ◽  
Vol 18 (9) ◽  
pp. 3028 ◽  
Author(s):  
VanDung Nguyen ◽  
Tran Anh Khoa ◽  
Thant Zin Oo ◽  
Nguyen H. Tran ◽  
Choong Seon Hong ◽  
...  
Keyword(s):  
Multiple Access ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
Mac Protocol ◽  
Media Access Control ◽  
Delivery Ratio ◽  
Media Access ◽  
Traffic Conditions ◽  
Hoc Networks ◽  
Transmission Overhead

In vehicular ad hoc networks (VANETs), many schemes for a multi-channel media access control (MAC) protocol have been proposed to adapt to dynamically changing vehicle traffic conditions and deliver both safety and non-safety packets. One such scheme is to employ both time-division multiple access (TDMA) and carrier-sense multiple access (CSMA) schemes (called a hybrid TDMA/CSMA scheme) in the control channel (CCH) interval. The scheme can adjust the length of the TDMA period depending on traffic conditions. In this paper, we propose a modified packet transmitted in the TDMA period to reduce transmission overhead under a hybrid TDMA/CSMA multi-channel MAC protocol. Simulation results show that a MAC protocol with a modified packet supports an efficient packet delivery ratio of control packets in the CCH. In addition, we analyze the hybrid TDMA/CSMA multi-channel MAC protocol with the modified packet under saturated throughput conditions on the service channels (SCHs). The analysis results show that the number of neighbors has little effect on the establishment of the number of time slots in TDMA periods and on SCHs under saturated throughput conditions.

scholarly journals A QoS Based Adaptive Backoff Scheme for Vehicular Ad Hoc Networks

Sensors ◽  
2018 ◽  
Vol 18 (12) ◽  
pp. 4421 ◽  
Author(s):  
Tianjiao Zhang ◽  
Qi Zhu
Keyword(s):  
Ad Hoc Networks ◽  
Network Performance ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
Intelligent Transportation System ◽  
Mac Protocol ◽  
Media Access Control ◽  
Media Access ◽  
The Media ◽  
Hoc Networks

The media access control (MAC) protocol is a key element in the design of vehicular ad hoc networks (VANETs) that directly affects the network performance. The backoff schemes of existing MAC protocols apply the single backoff process and therefore are not suitable for multi-class data transmission. Additionally, they cannot satisfy the delay requirements of emergency data in the case of varying number of vehicles, causing an adverse effect to the intelligent transportation system (ITS). This paper presents a priority-based adaptive backoff scheme that can enhance the binary exponential backoff (BEB) algorithm as well as the polynomial backoff (QB) algorithm. This system distinguishes priority data with different delay requirements first and designs different backoff schemes for each type of data later. The two-dimensional Markov Chain is used to analyze the backoff scheme and determine the expressions for throughput and delay. The simulation results show that the backoff scheme provided by this paper can reduce the average data delay and regulate each kind of data delay adaptively, according to the varying number of vehicles and different delay requirements.

scholarly journals A hybrid access method for broadcasting of safety messages in IEEE 802.11p VANETs

2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Xiaoying Lei ◽  
Xiangjin Chen ◽  
Seung Hyong Rhee
Keyword(s):  
Access Control ◽  
Multiple Access ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
Mac Protocol ◽  
Ieee 802.11P ◽  
Media Access Control ◽  
Access Method ◽  
Safety Message ◽  
Hybrid Access

AbstractVehicular Ad-hoc Networks (VANETs) can improve the road safety by transmitting safety-critical messages such as beacons and emergency messages. IEEE 802.11p VANETs have adopted the carrier sense multiple access with collision avoidance (CSMA/CA) mechanism for the multiple access control. The 802.11p media access control (MAC) protocol, however, can not guarantee the reliability of broadcasting data, since the reception of transmitted messages are not acknowledged. Moreover, the backoff scheme of the 802.11p MAC utilizes a fixed-size contention window for safety message broadcasting, which causes high collision probabilities especially in dense environments. In order to improve such drawbacks, we propose a hybrid access method as follows: Nodes are equipped to reserve time slots for the next round of broadcasting, while unoccupied time slots are preserved for those which have emergency needs. In addition, implicit feedbacks are enabled for detecting collisions incurred during random channel accesses in preserved time slots. We devise a mathematical model which optimally controls the parameters of our scheme while minimizes the cost caused by idle channels and collisions. Extensive simulations show that our mechanism can remarkably improve the performance of VANETs in broadcasting of the safety messages.

scholarly journals 802.11p Profile Adaptive MAC Protocol for Non-Safety Messages on Vehicular Ad Hoc Networks

2018 ◽  
Vol 12 (1) ◽  
pp. 208
Author(s):  
Shamsul J Elias ◽  
M. Elshaikh ◽  
M. Yusof Darus ◽  
Jamaluddin Jasmis ◽  
Angela Amphawan
Keyword(s):  
Ad Hoc Networks ◽  
Congestion Control ◽  
Data Transmission ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
Mac Protocol ◽  
Packet Delivery Ratio ◽  
Delivery Ratio ◽  
Packet Delivery ◽  
Hoc Networks

<p>Vehicular Ad hoc Networks (VANET) play a vital Vehicle to Infrastructure (V2I) correspondence frameworks where vehicle are convey by communicating and conveying data transmitted among each other. Because of both high versatility and high unique network topology, congestion control should be executed distributedly. Optimizing the congestion control in term of delay rate, packet delivery ratio (PDR) and throughput could limit the activity of data packet transmissions. These have not been examined altogether so far – but rather this characteristic will be fundamental for VANET system execution and network system performance. This paper exhibits a novel strategy for congestion control and data transmission through Service Control Channel (SCH) in VANET. The Taguchi strategy has been connected in getting the optimize value of parameter for congstion control in highway environment. This idea lessens the pointless activity of data transmission and decreases the likelihood of congested in traffic in view of execution for measuring the delay rate, packet delivery ratio (PDR) and throughput. The proposed execution performance is estimated with the typical VANET environment in V2I topology in highway driving conditions and the simulation results demonstrate and enhance network execution performance with effective data transmission capacity.</p>

Modified fuzzy-based greedy routing protocol for VANETs

2020 ◽  
Vol 39 (6) ◽  
pp. 8357-8364
Author(s):  
Thompson Stephan ◽  
Ananthnarayan Rajappa ◽  
K.S. Sendhil Kumar ◽  
Shivang Gupta ◽  
Achyut Shankar ◽  
...  
Keyword(s):  
Fuzzy Logic ◽  
Routing Protocol ◽  
Intelligent Transportation Systems ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
Research Area ◽  
Transportation Systems ◽  
Delivery Ratio ◽  
Greedy Routing ◽  
Hoc Networks

Vehicular Ad Hoc Networks (VANETs) is the most growing research area in wireless communication and has been gaining significant attention over recent years due to its role in designing intelligent transportation systems. Wireless multi-hop forwarding in VANETs is challenging since the data has to be relayed as soon as possible through the intermediate vehicles from the source to destination. This paper proposes a modified fuzzy-based greedy routing protocol (MFGR) which is an enhanced version of fuzzy logic-based greedy routing protocol (FLGR). Our proposed protocol applies fuzzy logic for the selection of the next greedy forwarder to forward the data reliably towards the destination. Five parameters, namely distance, direction, speed, position, and trust have been used to evaluate the node’s stability using fuzzy logic. The simulation results demonstrate that the proposed MFGR scheme can achieve the best performance in terms of the highest packet delivery ratio (PDR) and minimizes the average number of hops among all protocols.

Media Access Control Protocol with Differential Service in Aeronautical Frequency-Hopping Ad Hoc Networks

2014 ◽  
Vol 24 (8) ◽  
pp. 2214-2225 ◽  
Author(s):  
Ye-Qun WANG ◽  
Feng YANG ◽  
Guo-Ce HUANG ◽  
Heng-Yang ZHANG ◽  
Jian-Xin GUO
Keyword(s):  
Access Control ◽  
Ad Hoc Networks ◽  
Ad Hoc ◽  
Frequency Hopping ◽  
Media Access Control ◽  
Media Access ◽  
Control Protocol ◽  
Hoc Networks ◽  
Media Access Control Protocol

Performance Analysis of a Flexible MAC Protocol for Real-Time Services in Vehicular Ad-Hoc Networks

2005 ◽  
Vol 12 (3) ◽  
pp. 147-157
Author(s):  
Giuseppe Caizzone ◽  
Paolo Giacomazzi ◽  
Luigi Musumeci ◽  
Gabriella Saddemi ◽  
Giacomo Verticale
Keyword(s):  
Performance Analysis ◽  
Ad Hoc Networks ◽  
Real Time ◽  
Vehicular Ad Hoc Networks ◽  
Ad Hoc ◽  
Mac Protocol ◽  
Hoc Networks
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