0000000000406644
AUTHOR
Pedro Cuenca
QoS Support for Time-Constrained Multimedia Communications in IEEE 802.11 WLANs: A Performance Evaluation
During the past few years, we have been witnessing the massive deployment of IEEE 802.11 wireless LANs. Even though the widespread deployment of such wireless LANs, many studies are still underway aiming to design and develop simple yet effective QoS mechanisms for supporting time-constrained services over such platforms. In this paper, we first overview five different QoS mechanisms recently introduced in the literature as well as the upcoming IEEE 802.11e (EDCA) standard. We then carry out a comparative performance evaluation of all the QoS mechanisms. We focus our study on the effectiveness of the various QoS mechanisms for supporting time-constrained services.
QoS Mechanisms for IEEE 802.11 Wireless LANs
Currently the Internet provides users with access to information across the world using IP technology. Until now most access points to the Internet have been fixed stations at given locations, but with increasing sales of mobile devices, mobility has become a major trend. Therefore, the Internet is becoming more and more heterogeneous due to the recent explosion of wireless networks. The IEEE 802.11 wireless LAN (WLAN) is the most widely used WLAN standard nowadays. Currently the IEEE 802.11 standard specifies an over-the-air interface between wireless devices. However, QoS services over this technology are still being defined aiming to provide support to multiple applications. Thus, a larg…
Guaranteed access mode for downlink traffic over IEEE 802.11 WLANs
IEEE 802.11 networks present an unfairness problem between the downlink and uplink traffic, using the default settings of the Enhanced Distributed Channel Access (EDCA). In order to reduce this unfairness, the Access Point (AP) can adapt the standard parameters, but this is not enough. In this paper, we propose simple and efficient solutions, which are implemented at the AP, thus they are standard compatible and no modifications to the current hardware and protocol stacks are needed. These solutions aim at providing guaranteed access to the downlink traffic when the AP perceives the unfairness problem. Our simulation results show a reduction in the unfairness and an enhancement in network p…