naa a22 4500 510791549 CHVBK 20180411083321.0 cr unu---uuuuu 180411e20130701xx s 000 0 eng 10.1007/s11277-012-0823-z doi (NATIONALLICENCE)springer-10.1007/s11277-012-0823-z Efficient Back-off Mechanism for Multimedia Support in 802.11e EDCA Wireless Ad-Hoc Networks [Elektronische Daten] [Aws Shakir, Chee Ng, Nor Noordin, Alyani Ismail] This paper presents an effective back-off mechanism to improve quality of service (QoS) for multimedia applications over the IEEE 802.11e enhanced distribution channel access (EDCA) standard. It can be done with proposed algorithm called dynamic fast adaptation for contention-based EDCA (DFA-EDCA) mechanism. The main concept of proposed DFA-EDCA mechanism is to use the exponential functions to adaptively tune the back-off parameters in IEEE 802.11e EDCA according to the changes on a network load within a short period. In this proposed mechanism an intra-access category (intra-AC) differentiation mechanism is provided to increase its back-off time randomly and achieve discrimination of same priority traffic on different stations. The performance evaluations have been conducted by using Network Simulator (NS-2). The simulation results show that the proposed DFA-EDCA mechanism has greatly outperformed the previous mechanisms such as non-linear dynamic adaptation scheme of the minimum contention window (CWmin-HA), dynamic adaptation algorithm of the maximum contention window (CWmax-adaptation), adaptive enhanced distributed coordination function and the conventional EDCA in terms of goodput, gain of goodput, packet delay, collision rate and channel utilization ratio (CUR). It has significantly reduced both packet delay and collision rate simultaneously together with an obviously increment in both goodput and CUR, which lead to the improvement in QoS for multimedia applications. Springer Science+Business Media, LLC., 2012 IEEE 802.11e nationallicence EDCA nationallicence Back-off mechanism nationallicence Contention window nationallicence Shakir Aws Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aut Ng Chee Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aut Noordin Nor Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aut Ismail Alyani Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aut Wireless Personal Communications Springer US; http://www.springer-ny.com 71/1(2013-07-01), 439-466 0929-6212 71:1<439 2013 71 11277 https://doi.org/10.1007/s11277-012-0823-z text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/s11277-012-0823-z text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shakir Aws Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aut NATIONALLICENCE 700 1- Ng Chee Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aut NATIONALLICENCE 700 1- Noordin Nor Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aut NATIONALLICENCE 700 1- Ismail Alyani Department of Computer and Communication Systems Engineering, Faculty of Engineering, Universiti Putra Malaysia, 43400 UPM, Serdang, Selangor, Malaysia aut NATIONALLICENCE 773 0- Wireless Personal Communications Springer US; http://www.springer-ny.com 71/1(2013-07-01), 439-466 0929-6212 71:1<439 2013 71 11277 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer