A performance study of roaming in wireless local area networks based on IEEE 802.11r

The wide deployment of IEEE 802.11 based wireless local area networks (WLANs), and increased interest in multimedia applications support in WLANs, have lead to the need to support real-time applications even when devices are roaming across WLAN access points (APs). This has lead to the development of the IEEE 802.11r fast roaming mechanism, in which a connection to a candidate AP is established before the loss of connectivity with the current one. In this paper, we study the performance of the IEEE 802.11r and its viability for real-time applications. Our simulation results demonstrate the flexibility of the IEEE 802.11r and the effectiveness of its roaming procedure. Also, a noticeable reduction in roaming time and delays at APs is shown to be achievable, which guarantees the required quality of service level of Voice over IP over WLAN (VoWLAN) applications.