A Testbed About Priority-Based Dynamic Connection Profiles in QoS Wireless Multimedia Networks

The ever-growing demand of high-quality broadband connectivity in mobile scenarios, as well as the Digital Divide discrimination, are boosting the development of more and more efficient wireless technologies. Despite their adaptability and relative small installation costs, wireless networks still lack a full bandwidth availability and are also subject to interference problems. In context of a Metropolitan Area Network serving a large number of users, a bandwidth increase can turn out to be neither feasible nor justified. In consequence, and in order to meet the needs of multimedia applications, bandwidth optimization techniques were designed and developed, such as Traffic Shaping, Policy-Based Traffic Management and Quality of Service (QoS). In this paper, QoS protocols are adopted and, in particular, priority-based dynamic profiles in a QoS wireless multimedia network. This technique allows to asssign different priorities to distinct applications, so as to rearrange service quality in a dynamic way and guarantee the desired performance to a given data flow

An Adaptive Fair-Distributed Scheduling Algorithm to Guarantee QoS for Both VBR and CBR Video Traffics on IEEE 802.11e WLANs

Most of the centralized QoS mechanisms for WLAN MAC layer are only able to guarantee QoS parameters for CBR video traffic effectively. On the other hand, the existing distributed QoS mechanisms are only able to differentiate between various traffic streams without being able to guarantee QoS. This paper addresses these deficiencies by proposing a new distributed QoS scheme that guarantees QoS parameters such as delay and throughput for both CBR and VBR video traffics. The proposed scheme is also fair for all streams and it can adapt to the various conditions of the network. To achieve this, three fields are added to the RTS/CTS frames whose combination with the previously existing duration field of RTS/CTS frames guarantees the periodic fair adaptive access of a station to the channel. The performance of the proposed method has been evaluated with NS-2. The results showed that it outperforms IEEE 802.11e HCCA

Telecommunications Networks

This book guides readers through the basics of rapidly emerging networks to more advanced concepts and future expectations of Telecommunications Networks. It identifies and examines the most pressing research issues in Telecommunications and it contains chapters written by leading researchers, academics and industry professionals. Telecommunications Networks - Current Status and Future Trends covers surveys of recent publications that investigate key areas of interest such as: IMS, eTOM, 3G/4G, optimization problems, modeling, simulation, quality of service, etc. This book, that is suitable for both PhD and master students, is organized into six sections: New Generation Networks, Quality of Services, Sensor Networks, Telecommunications, Traffic Engineering and Routing