Multimedia-MAC protocol: its performance analysis and applications for WDM networks

The design of the medium-access control (MAC) protocol is the most crucial aspect for high-speed and high-performance local and metropolitan area networks, since the decisions made at this level determine the major functional characteristics of these networks. Most of the MAC protocols proposed in the literature are not suitable for multimedia applications, since they have been designed with one generic traffic type in mind. As a result, they perform quite well for the traffic types they have been designed for, but poorly for other traffic streams with different characteristics. In this paper, we propose an integrated MAC protocol called the Multimedia-MAC (M-MAC), which integrates different MAC protocols into a hybrid protocol in a shared-medium network to efficiently accommodate various types of multimedia traffic streams with different characteristics and quality-of-service demands, namely, a constant-bit-rate traffic, bursty traffic (say, variable-bit-rate traffic), and emergency messages (say, control messages). We have developed a mathematical framework for the analysis and performance evaluation of our M-MAC protocol, which involves a queueing system with vacation. We have applied our M-MAC design approach to a wavelength-division multiplexing network, and evaluated its performance under various traffic conditions.     

Efficient protocols for multimedia streams on WDMA networks

This paper introduces a new approach to integrate different types of medium access control (MAC) protocols into a single wavelength-division-multiplexing (WDM) network system. The WDM network is based on a passive star coupler, and the purpose of integrating different MAC protocols is to efficiently accommodate various types of multimedia traffic streams with different characteristics and quality of service demands. Our integrated MAC protocol is termed multimedia wavelength-division multiple-access (M-WDMA). Three types of multimedia traffic streams are considered in this paper: constant-bit-rate traffic and two classes of variable-bit-rate traffic. Accordingly, three tunable transmitters and one fixed home channel receiver are used in the design of each WDM node. The transmitters transmit the three types of multimedia traffic streams in a pipeline fashion so as to overcome the tuning time overhead and to support parallel transmissions of traffic streams that emerge simultaneously. We further incorporate a dynamic bandwidth allocation scheme that dynamically adjusts the portions of bandwidth occupied by the three types of traffic streams according to their demands. Consequently the M-WDMA protocol achieves high utilization and efficiently adapts to the demands of the multimedia streams so as to guarantee their QoS. The performance of the M-WDMA is evaluated through a simple analytical model and extensive discrete-event simulations. It is shown that the M-WDMA can satisfy the QoS requirements of various mixes of multimedia traffic streams even under very stringent requirements. Moreover, we show that the M-WDMA outperforms conventional MAC protocols for WDM networks. As a result, we expect M-WDMA to be a good multimedia MAC candidate protocol for future-generation WDM networks.     

流量自适应媒体访问控制协议的研究与设计

针对媒体访问控制(MAC)协议在无线传感器网络中的作用与要求,分析了典型的MAC协议,提出流量自适应改进方案,并用NS2对其进行了性能测试.仿真结果表明,在网络节点分布较为密集,突发数据流量变化较大的网络环境中,流量自适应MAC协议的能量效率、吞吐率和网络延迟都有较大的改善.     

Integrating high quality video streams with FTP traffic over a noisy high capacity wireless cellular channel

In this paper we propose and evaluate a Medium Access Control (MAC) protocol for the efficient integration of high quality video traffic with ftp data packet traffic over a wireless cellular channel of very high capacity. We envision a system where the mobile terminals are considered to be high performance devices with extended storage capabilities which can act like cache memories streaming multimedia material. Via an extensive simulation study we evaluate the system’s performance under a variety of possible loads which consist of actual MPEG-4 streams and ftp sessions, and we show that our scheme outperforms another, well-known MAC protocol for cellular networks.     

Performance analysis of MAC layer protocols in the IEEE 802.11 wireless LAN

In recent years, WLANs (Wireless Local Area Networks) based on the IEEE 802.11 standard have been taken a growing interest and developed widely all over the world. CSMA/CA (Carrier Sense Multiple Access with Collision Avoidance) protocols are the most popular MAC (Medium Access Control) protocols for WLANs. The performance of CSMA/CA protocols over wireless channels has been investigated over the past years. In this paper, we obtain the probability distribution function of the MAC layer packet service time, and we present the comprehensive performance analysis of IEEE 802.11 MAC protocol by investigating the queue dynamics of a wireless station based on the MAC layer packet service time. We adopt an MMPP(Markov Modulated Poisson Process) as the input traffic model that describes well the bursty nature of Internet traffic. The analysis on the throughput and the delay performance has been carried out by using the MMPP/G/1/K queueing model. We have some numerical results that represent the system throughput and the queue dynamics including the mean packet waiting time and packet blocking probability.     

无线传感器网络休眠MAC协议分析

无线传感器网络中每个传感器节点一般采用电池供电,能量有限,需要有效的可休眠的MAC协议来保持能量的高效利用,因此休眠MAC协议成为研究的重要方向之一。目前已经有很多种为无线传感器网络设计的MAC协议,其中一个重要的分支就是基于局部同步周期休眠／监听排程的S-MAC协议及其各种改进协议。论文首先介绍了无线传感器网络中与MAC协议设计相关的一些特性。其次对S-MAC协议的基本原理以及各种改进协议的原理进行了说明,并分析了它们各自的优缺点。     

无线体域网节能MAC协议综论(英文)

In this paper, we provide a comprehensive survey of key energy-efficient Medium Access Control (MAC) protocols for Wireless Body Area Networks (WBANs). At the outset, we outline the crucial attributes of a good MAC protocol for WBAN. Several sources that contribute to the energy inefficiency of WBAN are identified, and features of the various MAC protocols qualitatively compared. Then, we further investigate some representative TDMA-based energy-efficient MAC protocols for WBAN by emphasizing their strength...     

无线局域网与无线个域网QoS机制的对比分析

无线局域网(WLAN)和无线个域网(WPAN)技术的发展带来的多媒体业务流量的剧增,使无线网络的资源管理、服务质量(QoS)保障等问题日益突出。传统的媒体访问控制(MAC)协议需要重新设计才能对无线网络的QoS问题进行有效地解决。文中研究了IEEEWLAN和WPAN工作组分别于2002年5月和2003年2月提出的IEEE802.11eD3.0和IEEE802.15.3D16两种协议标准的工作机制并对两者的性能作出了比较分析。     

Performance Evaluation of a New MAC Protocol for the CDMA Interconnection Network

A CDMA mobile system consists of subsystems that transmit and receive call control messages and traffic messages through the CDMA Interconnection Network (CIN). To assure high throughput and short delay in the CIN, an efficient Medium Access Control (MAC) protocol should be provided.In this study, we propose a new MAC protocol for CDMA interconnection networks in order to provide real-time communications in CDMA mobile systems. Also, we evaluate the delay performance of the proposed MAC protocol and compare it with that of existing MAC protocol. Through numerical examples, we show that the proposed protocol provides better delay performance than the existing protocol.     

Using traffic prediction and estimation of provider revenue for a joint GEO satellite MAC/CAC scheme

Satellite networks present an attractive solution in providing worldwide access to the present and future generation multimedia communication services. However, the burstiness of multimedia traffic and the long propagation delays in Geostationary (GEO) satellite systems call for an efficient Medium Access Control (MAC) protocol and an equally efficient Call Admission Control (CAC) scheme, in order to provide acceptable Quality of Service (QoS) to multimedia users. This paper proposes a fair and dynamic CAC and MAC framework, named Fair Predictive Resource Reservation Access (FPRRA), which is based on accurate videoconference traffic prediction and makes decisions after taking into account the provider revenue. The framework’s performance is evaluated in comparison to other efficient schemes from the literature.     

Providing Real-Time Service in CDMA Wireless Networks

Medium Access Control (MAC) protocol design plays a very important role in the design of wireless networks. In this paper, we propose a new MAC protocol to provide real-time service for a CDMA wireless network. This protocol has been designed based on the distributed queuing random access protocol for CDMA wireless networks (DQRAP/CDMA). As real-time scheduling schemes have been introduced into the protocol design, the new protocol has an ability to accommodate real-time traffic in the CDMA wireless networks. A series of simulation experiments have been carried out to evaluate the performance of the proposed protocol. The results reveal that the proposed protocol can efficiently provide real-time service to the traffic composed of time constrained messages in the CDMA wireless networks.     

Performance analysis of the distributed queuing collision avoidance (DQCA) protocol with link adaptation

DQCA is a near-optimum Medium Access Control (MAC) protocol designed for Wireless Local Access Networks (WLANs). The protocol operates as a random access scheme under low traffic load and switches smoothly and automatically to a reservation scheme as the traffic grows. The inherent feedback mechanism of DQCA facilitates the implementation of a link adaptation algorithm that properly selects the best transmission rate taking into account the state of the wireless channel. This paper presents an analytical model for the evaluation of the performance in terms of throughput and mean message delay in the presence of a time-variant channel response.     

A Detailed Review of Multi-Channel Medium Access Control Protocols for Wireless Sensor Networks

Most applications of Wireless Sensor Networks (WSNs) assume the presence of single-channel Medium Access Control (MAC) protocols. In the usual dense deployment of the sensor networks, single-channel MAC protocols may be deficient because of radio collisions and limited bandwidth. Hence, using multiple channels can significantly improve the performance of WSN. Recent developments in sensor technology, as seen in Crossbow’s MICAz Mote, Rockwell’s WINS nodes and IEEE 802.15.4 Zigbee, have enabled support for multi-channel communications. Several multi-channel MAC protocols with different objectives have been proposed for WSNs in literature. This paper surveys and classifies the state-of-the-art multi-channel MAC protocols that are proposed for WSNs. It first outlines the sensor network properties that are crucial for designing a MAC protocol. It subsequently reviews the existent challenges to design a good multi-channel MAC protocol for the sensor networks. Then, several multi-channel MAC protocols specifically proposed for the WSNs are inspected in detail and compared with each other. Finally, some open issues in this area are outlined for future research.     

An adaptive reservation scheme for VBR voice traffic in wireless ATM networks

A reservation scheme, named dynamic hybrid partitioning, is proposed for the Medium Access Control (MAC) protocol of wireless ATM (WATM) networks operating in Time Division Duplex (TDD) mode. The goal is to improve the performance of the real-time Variable Bit Rate (VBR) voice traffic in networks with mixed voice/data traffic. In most proposed MAC protocols for WATM networks, the reservation phase treats all traffic equally, whether delay-sensitive or not. Hence, delay-sensitive VBR traffic sources have to compete for reservation each time they wake up from idle mode. This causes large and variable channel access delays, and increases the delay and delay variation (jitter) experienced by ATM cells of VBR traffic. In the proposed scheme, the reservation phase of the MAC protocol is dynamically divided into a contention-free partition for delay-sensitive idle VBR traffic, and a contention partition for other traffic. Adaptive algorithms dynamically adjust the partition sizes to minimize the channel bandwidth overhead. Simulation results show that the delay performance of delay-sensitive VBR traffic is improved while minimizing the overhead.     

A Distributed Cooperative MAC Protocol for QoS Improvement and Mobility Support in WiMedia Networks

A Distributed Medium Access Control (D-MAC) protocol based on UWB for high-rate Wireless Personal Area Networks is specified by the WiMedia Alliance. D-MAC protocol is suitable for ubiquitous connection in home networks, military/medical applications due to its inexpensive cost, low power consumption, high data rate, and distributed approach. In contrast to IEEE 802.15.3, D-MAC makes all devices have the same functionality. And its networks are self-organized and provide devices with functions such as access to the medium, channel allocation to devices, data transmission, quality of service and synchronization in a distributed manner. D-MAC fundamentally removes the problems of the centralized MAC approach revealed at IEEE 802.15.3 MAC by adopting a distributed architecture. However, the current D-MAC can’t prevent QoS degradations, occurred by mobile nodes with low data rate due to bad channel status, which cause critical problems in QoS provisioning to isochronous streams and mobile applications. Therefore, we propose a distributed cooperative MAC protocol for multi-hop WiMedia networks using virtual MIMO links. Based on instantaneous Channel State Information among WiMedia devices, our proposed protocol can intelligently select the transmission path with higher data rate to provide advanced QoS with minimum delay for real-time multimedia streaming services.     

A preamble-based approach for providing quality of service support in wireless sensor networks

Medium Access Control (MAC) protocols for Wireless Sensor Networks (WSN) are usually designed as random access protocols that apply different kinds of backoff strategies since Time Division Multiple Access (TDMA) based protocols with admission control are very complex and require additional mechanisms for synchronization. Without such mechanisms, fair or priority based medium access with Quality of Service (QoS) guarantees can hardly be achieved by existing protocols. Therefore, we developed a random access protocol which uses a new preamble-based medium access strategy that enables collision-free priority based access without the need of synchronization. In this paper we introduce different QoS strategies and their use cases. All strategies can be easily integrated in our protocol to meet the requirements of different target applications. Furthermore, we compare the performance of the strategies with a typical carrier-sense based protocol.     

无线传感器网络MAC协议的研究与改进

研究和分析了当前无线传感器网络(WSN)中介质访问控制(MAC)协议、IEEE802.11和IEEE802.15.4 MAC协议的各种性能,并结合传感网络介质访问协议(S-MAC)中低占空比休眠机制对IEEE802.15.4介质访问协议进行改进.用NS-2仿真软件对各种协议进行仿真,仿真结果表明改进后的MAC协议可大...     

Integration of differentiated services with fairness control on a WDM metro ring

This study develops a Fair and Efficient Integrated Media Access Control (FEIMAC) protocol, designated FEIMAC, for a wavelength division multiplexing (WDM) dual-ring network known as FT²-TR². This system is an extended version of the original unidirectional FT-TR ring architecture, in which the nodes are equipped with a fixed-tuned transmitter and a tunable receiver on each ring. FEIMAC is derived from the Fairness Control with Collision Avoidance (FCCA) protocol proposed in a previous study by the current authors (Chang, W.-R. et al.: FCCA: A reverse- direction-based MAC protocol suite for WDM Metropolitan Ring Networks, Proc. of IEEE APCC ′05, Perth, Australia, October 2005, pp. 946–950). FCCA is a collision-free medium access control (MAC) protocol, which achieves an efficient exploitation of the available bandwidth while guaranteeing each node a fair access to the network resources. In addition to the capabilities described above, FEIMAC employs a framed approach, in which each frame consists of a “real-time subframe” followed by a “best-effort subframe”, to support differentiated services of real-time and best-effort traffic streams. The simulation results demonstrate the effectiveness and efficiency of the proposed integrated protocol.     

无线传感器网络S-MAC协议研究

传感器节点能量受限,节能是传感器网络中媒体访问控制（MAC）协议设计的首要问题。采用周期性睡眠机制、自适应侦听机制、串音避免机制和消息传递机制可使得传感器媒体访问控制（S-MAC）协议在网络能耗和时延方面得到改进。对S-MAC协议的改进主要有两种方式：动态调整、区别控制包与数据包的发送条件进行发送。对无线传感器网络,要想设计出一种满足各方面要求的MAC协议是不现实的,可针对不同应用的要求,灵活采用不同的方式,设计出相应的协议。     

A new MAC protocol for broadband wireless communications and its performance evaluation

This paper presents a new Time Division Multiple Access/Frequency Division Duplexing (TDMA/FDD) based Medium Access Control (MAC) protocol for broadband wireless networks, supporting Quality of Service (QoS) for real-time multimedia applications. It also gives the Call Blocking Probability (CBP), packet end-to-end delay and utilization analysis of different service classes, as they are most essential performance criterions in broadband wireless network assessment. The Connection Admission Control (CAC) mechanism in the proposed MAC efficiently organizes the bandwidth allocation for different service classes by means of a fairness based scheduling algorithm. In addition, the simulation model of the proposed MAC scheme is realized by using OPNET Modeler network simulator. The results of the analytical calculations for the CBPs are compared to those of the simulation of the proposed MAC, thus validity of the MAC protocol is proved.