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Collision Free MAC Protocols for Wireless Ad Hoc Networks based on BIBD Architecture  [cached]
Pietro Camarda,Orazio Fiume
Journal of Communications , 2007, DOI: 10.4304/jcm.2.7.1-8
Abstract: Wireless Ad hoc networks represent a powerful telecommunication infrastructure that is being exploited for enabling general wireless networking connectivity for a variety of significant applications, e.g., military applications, industrial automation, sensor networks, vehicular networks, applications in case of disaster, etc.The distributed and flexible architecture of wireless ad hoc networks is a key factor, however, their wide deployment relies on protocols able to provide energetic optimization, high channel utilization, support for real time traffic, etc. In such a context, recently a Collision Free MAC protocol (CFMAC), based on the theory of Balanced Incomplete Block Design (BIBD), has been proposed. Its effectiveness has been already investigated showing significant improvements compared to the Standard IEEE 802.11, in terms of throughput, one -way packet delay, energy consumption and support of real time traffic.In this paper enhanced versions of CF-MAC have been considered with significant novelties regarding the introduction of variable time slot dimension, different management of Power Saving (PS) mechanisms, more efficient utilization of channel bandwidth, etc. The performance of these variants have been investigated by simple analytical models, in terms of energy saving, channel utilization, average access delay, etc., highlighting their improvements over basic CF-MAC protocol. In addition, computer simulations have been exploited to study the suitability of the proposed schemes to support VoIp applications.
Mac Protocols in Mobile Ad Hoc Networks  [cached]
Nermin Makhlouf,Pavel Vajsar
International Journal of Advances in Telecommunications, Electrotechnics, Signals and Systems , 2012, DOI: 10.11601/ijates.v1i1.4
Abstract: Mobile Ad hoc NETwork (MANET) is a wireless net- work of mobile nodes connected by wireless link without a central control. The Medium Access Control (MAC) protocol is one of the important issues in such network, thereby the presented paper will discuss the MAC protocol used in MANET depending on IEEE 802.11 standard which known as Distributed Coordination Function (DCF).However, the limitation of MANET is that, the collision increases with the rise of nodes number. Therefore paper study the MAC protocol using directional antennas to reduce the collisions, increase the range of transmission and largely reduce the interference between the directions. However, the main problem of using directional antennas is caused by frequent node mobility. So the movement plays a vital role in wireless Ad hoc networks to predict the location of MNs.
Comparative Study of MAC Protocols for Mobile Ad Hoc Networks
Sanjeev Sharma,R.C. Jain,Sarita Bhadauria,Ramesh Cherukuru
International Journal of Soft Computing , 2012,
Abstract: Studies of ad hoc wireless networks are a relatively new field gaining more popularity for various new applications. In these networks, the Medium Access Control (MAC) protocols are responsible for coordinating the access from active nodes. These protocols are of significant importance since the wireless communication channel is inherently prone to errors and unique problems such as the hidden-terminal problem, the exposed-terminal problem, and signal fading effects. Although a lot of research has been conducted on MAC protocols, the various issues involved have mostly been presented in isolation of each other. We therefore make an attempt to present a comparative study of major schemes, integrating various related issues and challenges. We present a classification of MAC protocols and their brief description based on their operating principles and underlying features.
Survey of MAC Layer Protocols for vehicular Ad Hoc Network
Vimal Bibhu,Dhirendra Kumar Singh
International Journal of Information Technology and Computer Science , 2012,
Abstract: Vehicular Ad Hoc Network is currently challenge for the wireless networking and its researchers. In this paper we have proposed the survey of the different MAC Layer protocols of the wireless medium those can be implemented in the Vehicular Ad Hoc Networking. The survey is based upon the study of the different protocol on their MAC level and its performance factors is evaluated. The performance factor is extracted from the studied materials and current working conditions of the protocols. These all factors are mobility, accuracy, privacy and confidentiality, safety critical message priority, delay control and suitability on vehicle and roadside. According to analyzed performance factor the IEEE 802.11p Wave is most suitable protocol for the Vehicular Ad Hoc Network but it does not cover up all conditional requirements.
Delay-throughput analysis of multi-channel MAC protocols in ad hoc networks  [cached]
Nieminen Jari,J?ntti Riku
EURASIP Journal on Wireless Communications and Networking , 2011,
Abstract: Since delay and throughput are important Quality of Service parameters in many wireless applications, we study the performance of different multi-channel Media Access Control (MAC) protocols in ad hoc networks by considering these measures in this paper. For this, we derive average access delays and throughputs in closed-form for different multi-channel MAC approaches in case of Poisson arrivals. Correctness of theoretical results is verified by simulations. Performance of the protocols is analyzed with respect to various critical operation parameters such as number of available channels, packet size and arrival rate. Presented results can be used to evaluate the performance of multi-channel MAC approaches in various scenarios and to study the impact of multi-channel communications on different wireless applications. More importantly, the derived theoretical results can be exploited in network design to ensure system stability.
Collision Detection and the Design of Fair and Stable MAC Scheme for Wireless Ad Hoc Networks  [PDF]
Yongkang Xiao, Rong Xiao, Bo Sun
Communications and Network (CN) , 2013, DOI: 10.4236/cn.2013.53B2065
Abstract: Fairness and stability guarantee among TCP flows is very stubborn in wireless ad hoc networks. There is not a MAC protocol that can fulfill this acquirement until now. In this paper, we firstly reveal the in-depth causes of the severe TCP unfairness and instability problems in IEEE 802.11-based multihop networks. Then we utilize the collision detection mechanism of the IEEE 802.11 protocol which is often ignored by most of the people to design a novel collision detection mechanism-based MAC (CDMB-MAC) scheme to solve the short-term and long-term fairness and stability issues while providing a good aggregate throughput in many topologies.
Performance Analysis of Collision Avoidance MAC Protocol in Multi-hop Wireless Ad-hoc Network
I. Mustapha,J. D. Jiya,B. U. Musa,J. Usman
International Journal of Network and Mobile Technologies , 2011,
Abstract: Performance analysis of 802.11Medium Access Control (MAC) protocol has been carried out either by means of simulation or by means of analytical models with simplified back-off rule assumptions. BinaryExponential Back-off (BEB) is the widely used back-off mechanism in many contention-based IEEE 802.11 MAC protocols for its simplicity and good performance, but it has drawbacks especially in multi-hop ad hocnetwork and some new back-off schemes such as Multiplicative Increase and Linear Decrease (MILD) and Double Increment Double Decrement (DIDD) were proposed. This paper, investigate the performance ofcollision avoidance MAC protocol in multi-hop wireless ad-hoc network by adopting MILD back-off mechanism. A three state Markov chain is used to model the channel states and node states. These models were used to derive the duration time, steady-state probabilities of the states of node and throughput of Mobile Ad-hoc NETwork (MANET). Simulation results show no matter the value of average number of neighbors,transmission range , and length of DATA frames , the throughput of MANET always achieves the maximum value at some point of persistent probability and also the throughput of a MANETs increases with increase in persistent probability which is influenced by the number of neighbors, transmission range and length of DATA frame. On the other hand the throughput decreases with increase in sensing range which is also influenced by the number of neighbors, transmission range and length of DATA frame.
Research on MAC protocols for supporting QoS in mobile Ad hoc networks
Ad hoc网络中支持QoS的MAC协议研究 

ZHONG Mei,LI Yun,ZHAO Wei-liang,CHEN Qian-bin,LONG Ke-ping,
钟梅
,李云,赵为粮,陈前斌,隆克平

重庆邮电大学学报(自然科学版) , 2005,
Abstract: 支持QoS的MAC协议是Ad hoc网络提供QoS保证的关键。因此,对Ad hoc网络中基于IEEE 802.11 DCF的支持QoS的分布式MAC协议进行了综述,并对该协议的已有研究成果作了分类,阐述了它们的基本原理以及优缺点,同时还讨论了该协议存在的问题和进一步的研究方向。
Performance Evaluation of a Novel Fuzzy Based Priority Scheduler for Mobile Ad-hoc Networks and its Effect on MAC Protocols  [PDF]
C. Gomathy,S. Shanmugavel
Information Technology Journal , 2005,
Abstract: As mobile computing gains popularity, the need for Ad-hoc routing will continue to grow. Mobile Ad-hoc network is an autonomous system of mobile wireless nodes connected dynamically without any preexisting infrastructure. Here, since the nodes are mobile, the network topology changes rapidly and unpredictably over time. The QoS routing has challenging problems due to the network`s dynamic topology. The multi hop wireless forwarding of packets, broadcasting of control traffic and the fact that, all nodes may act as routers in addition to being sources and sinks of data in ad-hoc networks produce different Queuing behaviour. Hence, a scheduling algorithm to schedule the packets based on their respective priorities will improvetheperformanceofthenetwork. Here, we present a novel fuzzy based priority scheduler for mobile ad-hoc networks, to determine the priority of the packets. The performance of this scheduler is studied using GloMoSim and evaluated in terms of quantitative metrics such as packet delivery ratio, average end-to-end delay and throughput. It is found that the scheduler provides overall improvement in the performance of the system with three unicast routing protocols when run over different MAC protocols.
车载自组织网络MAC协议研究综述
A Survey of MAC Protocols in Vehicular Ad Hoc Networks
 [PDF]

汤恒亮, 吴昊, 孟嘉
Hans Journal of Wireless Communications (HJWC) , 2012, DOI: 10.12677/hjwc.2012.24014
Abstract: 近年来,随着车载通信系统的不断发展和自组织网络技术的日益成熟,将二者有机结合成一体的车载自组织网络(VANET, Vehicular Ad Hoc Networks)已引起学术界和工业界的极大关注。媒介接入控制(MAC, Medium Access Control)协议是保证移动终端能够公平有效地共享无线信道的必要手段,是车载自组织网络的关键技术之一。由于VANET自身的特点及不断增长的业务不同,现有自组织网络的MAC协议并不能直接用于车载自组织网络中。本文在简要介绍车载自组织网络特点和MAC协议基本原理的基础上,对车载自组织网络MAC协议的最新研究进展进行了综述,探讨了几种具有代表性的车载自组织网络MAC协议方案,分析了目前研究中存在的主要问题和挑战,并指出了该领域未来发展趋势。
In recent years, with the rapid development of vehicular communication systems and advanced ad hoc network technologies, Vehicular Ad Hoc Networks (VANET) which combines both of them has greatly attracted those people’s attention in academic and industry fields. As one of the key technologies in vehicular ad hoc networks, MAC (Medium Access Control) protocol is indispensable to ensure the mobile nodes share the wireless medium fairly and efficiently. Since the specific characteristics and the increased variety of services in VANET, MAC protocols which are designed for Mobile Ad Hoc Networks
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