A Case Study of Association Instability in Dense IEEE 802.11 Networks Association instability is a common phenomenon in dense networks. The decision of whether or not to perform a handoff between access points in an infrastructured IEEE 802.11 network is taken exclusively by the wireless client stations. Even without mobility, static client devices may decide to migrate to another access point with the goal of improving performance. However, the criteria used to perform handoffs are not defined by the IEEE 802.11 standard and, thus, are dependent on specific vendor implementations. In this paper, we use data from a real large scale network and run experiments to demonstrate that such implementations are commonly deficient, resulting in high levels of association instability in dense environments. By analyzing the implementation used by the most common devices, we were able to conclude that this instability, known as the xe2x80x9cpingpong effectxe2x80x9d, results from the direct usage of RSSI samples which are highly variable. Finally, we analyze the behavior of RSSI in indoor environments showing that its time series presents multimodal distribution. We argue that the findings presented in this study can help develop more stable handoff algorithms for dense wireless networks.

On LoadAware Cell Association Schemes for Group User Mobility in mmWave Networks While faster signal attenuation in millimeter wave (mmWave) networks is compensated by high antenna directivity, the effects of dynamic blockages can be mitigated by using connections to multiple access points (APs), and the choice of a proper cell association algorithm plays an essential role in optimizing the overall system performance. Despite numerous research efforts aimed at finding optimal cell associations, effects of user mobility have not been explicitly addressed. Particularly, mobility patterns are imperative in the case of mmWave directional access, as they impact the overall system performance and, thus, might affect the choice of optimal solutions.In this paper, we address correlated mobility typical for collective extended reality (XR) applications, using the example of reference point group mobility models (RPGM), where users migrate in groups or clusters. Assuming 3D beamforming and protocol settings of mmWave IEEE 802.11aday that operates at 60GHz, we compare the performance of two cell association schemes: baseline RSSIbased and loadaware algorithms, and provide important insights on optimization of loadaware scheme parameters, the choice of which is a dynamic function of antenna directivity and network density.