Quality of Service over Specific Link Layers: state of the art report

The Integrated Services concept is proposed as an enhancement to the current Internet architecture, to provide a better Quality of Service (QoS) than that provided by the traditional Best-Effort service. The features of the Integrated Services are explained in this report. To support Integrated Services, certain requirements are posed on the underlying link layer. These requirements are studied by the Integrated Services over Specific Link Layers (ISSLL) IETF working group. The status of this ongoing research is reported in this document. To be more specific, the solutions to provide Integrated Services over ATM, IEEE 802 LAN technologies and low-bitrate links are evaluated in detail. The ISSLL working group has not yet studied the requirements, that are posed on the underlying link layer, when this link layer is wireless. Therefore, this state of the art report is extended with an identification of the requirements that are posed on the underlying wireless link, to provide differentiated Quality of Service

Adaptive reservation TDMA protocol for wireless multimedia traffic

An Adaptive Reservation Time Division Multiple Access (AR-TDMA) control protocol for Wireless Asynchronous Transfer Mode (WATM) networks is proposed in this paper. AR-TDMA combines the advantages of distributed access and centralised control for transporting Constant Bit Rate (CBR), Variable Bit Rate (VBR) and Available Bit Rate (ABR) traffic efficiently over a wireless channel. The contention slots access for reservation requests is governed by two protocols, the Adaptive Framed Pseudo-Bayesian Aloha with Adaptive Slot Assignment (AFPBAASA) protocol and the Framed Pseudo-Bayesian Aloha with Adaptively Prioritised Controlled Capture (FPBAAPCC) protocol. Both protocols provide different access priorities to the control packets in order to improve the Quality-of-Service (QoS) offered to time sensitive connections. AR-TDMA also features a novel integrated resource allocation algorithm that efficiently schedules terminals’ reserved access to the wireless ATM channel by considering their requested bandwidth and QoS. Integration of CBR, voice, VBR, data and control traffic over the wireless ATM channel using the proposed AR-TDMA protocol is considered in the paper. The performance of the AR-TDMA in conjunction with the AFPBA-ASA protocol and FPBA-APCC protocol has been investigated and the simulation results are presented showing that the protocol satisfies the required QoS of each traffic category while providing a highly efficient utilisation of approximately 96% for the wireless ATM channel

A quantitative comparison of multiple access control protocols for wireless ATM

The multiple access control (MAC) problem in a wireless network has intrigued researchers for years. For a broad-band wireless network such as wireless ATM, an effective MAC protocol is very much desired because efficient allocation of channel bandwidth is imperative in accommodating a large user population with satisfactory quality of service. Indeed, MAC protocols for a wireless ATM network in which user traffic requirements are highly heterogeneous (classified into CBR, VBR, and ABR), are even more intricate to design. Considerable research efforts expended in tackling the problem have resulted in a myriad of MAC protocols. While each protocol is individually shown to be effective by the respective designers, it is unclear how these different protocols compare against each other on a unified basis. In this paper, we quantitatively compare seven recently proposed TDMA-based MAC protocols for integrated wireless data and voice services. We first propose a taxonomy of TDMA-based protocols, from which we carefully select seven protocols, namely SCAMA, DTDMA/VR, DTDMA/PR, DQRUMA, DPRMA, DSA++, and PRMA/DA, such that they are devised based on rather orthogonal design philosophies. The objective of our comparison is to highlight the merits and demerits of different protocol designs.published_or_final_versio

A performance study of multiple access control protocols for wireless multimedia services

The multiple access control (MAC) problem in a wireless network has intrigued researchers for years. For a broadband wireless multimedia network such as wireless ATM, an effective MAC protocol is very much desired because efficient allocation of channel bandwidth is imperative in accommodating a large user population with satisfactory quality of service. Indeed, MAC protocols for a wireless ATM network, in which user traffic requirements are highly heterogeneous (classified into CBR, VBR, and ABR), are even more intricate to design. Considerable research efforts expended in tackling the problem have resulted in a myriad of MAC protocols. While each protocol is individually shown to be effective by the respective designers, it is unclear how these different protocols compare against each other on a unified basis. We quantitatively compare seven previously proposed TDMA-based MAC protocols for integrated wireless data and voice services. We first propose a taxonomy of TDMA-based protocols, from which we carefully select seven protocols, namely SCAMA, DTDMA/VR, DTDMA/PR, D4RUMA, DPRMA, DSA++, and PRMA/DA, such that they are devised based on rather orthogonal design philosophies. The objective of our comparison is to highlight the merits and demerits of different protocol designs.published_or_final_versio

Energy-efficient wireless communication

In this chapter we present an energy-efficient highly adaptive network interface architecture and a novel data link layer protocol for wireless networks that provides Quality of Service (QoS) support for diverse traffic types. Due to the dynamic nature of wireless networks, adaptations in bandwidth scheduling and error control are necessary to achieve energy efficiency and an acceptable quality of service. In our approach we apply adaptability through all layers of the protocol stack, and provide feedback to the applications. In this way the applications can adapt the data streams, and the network protocols can adapt the communication parameters

Wireless industrial monitoring and control networks: the journey so far and the road ahead

While traditional wired communication technologies have played a crucial role in industrial monitoring and control networks over the past few decades, they are increasingly proving to be inadequate to meet the highly dynamic and stringent demands of today’s industrial applications, primarily due to the very rigid nature of wired infrastructures. Wireless technology, however, through its increased pervasiveness, has the potential to revolutionize the industry, not only by mitigating the problems faced by wired solutions, but also by introducing a completely new class of applications. While present day wireless technologies made some preliminary inroads in the monitoring domain, they still have severe limitations especially when real-time, reliable distributed control operations are concerned. This article provides the reader with an overview of existing wireless technologies commonly used in the monitoring and control industry. It highlights the pros and cons of each technology and assesses the degree to which each technology is able to meet the stringent demands of industrial monitoring and control networks. Additionally, it summarizes mechanisms proposed by academia, especially serving critical applications by addressing the real-time and reliability requirements of industrial process automation. The article also describes certain key research problems from the physical layer communication for sensor networks and the wireless networking perspective that have yet to be addressed to allow the successful use of wireless technologies in industrial monitoring and control networks

A quantitative comparison of multiple access control protocols for integrated voice and data services in a cellular wireless network

The multiple access control (MAC) problem in a tireless network has intrigued researchers for years. An effective MAC protocol is very much desired because efficient allocation of channel bandwidth is imperative in accommodating a large user population with satisfactory quality of service. MAC protocols for integrated data and voice services in a cellular wireless network are even more intricate to design due to the dynamic user population size and traffic demands. Considerable research efforts expended in tackling the problem have resulted in a myriad of MAC protocols. While each protocol is individually shown to be effective by the respective designers, it is unclear how these different protocols compare against each other on a unified basis. In this paper, we quantitatively compare six recently proposed TDMA-based MAC protocols for integrated wireless data and voice services. We first propose a taxonomy of TDMA-based protocols, from which we carefully select six protocols, namely CHARISMA, D-TDMA/VR, D-TDMA/FR, DRMA, RAMA, and RMAV, such that they are devised based on rather orthogonal design philosophies. The objective of our comparison is to highlight the merits and demerits of different protocol designs.published_or_final_versio

E2MaC: an energy efficient MAC protocol for multimedia traffic

Energy efficiency is an important issue for mobile computers since they must rely on their batteries. We present a novel MAC protocol that achieves a good energy efficiency of wireless interface of the mobile and provides support for diverse traffic types and QoS. The scheduler of the base station is responsible to provide the required QoS to connections on the wireless link and to minimise the amount of energy spend by the mobile. The main principles of the E2MaC protocol are to avoid unsuccessful actions, minimise the number of transitions, and synchronise the mobile and the base-station. We will show that considerable amounts of energy can be saved using these principles. In the protocol the actions of the mobile are minimised. The base-station with plenty of energy performs actions in courtesy of the mobile. We have paid much attention in reducing the cost of a mobile for just being connected. The protocol is able to provide near-optimal energy efficiency (i.e. energy is only spent for the actual transfer) for a mobile within the constraints of the QoS of all connections in a cell, and only requires a small overhead