EWMAX and NDIST: RSSI filtering mechanisms for handoff algorithms in dense networks

In the realm of dense IEEE 802.11 networks, the ping-pong effect and association instability pose significant challenges. This article delves into the development and evaluation of two innovative RSSI filtering mechanisms, NDIST and EWMAX, aimed at mitigating these issues. The study compares these mechanisms with six other established approaches, using real-world RSSI traces to ensure accurate and reproducible results. The evaluation focuses on key metrics such as stabilization errors, ping-pong frequency, and handoff delay, providing a comprehensive analysis of each mechanism's performance. The findings reveal that EWMAX outperforms the other mechanisms, offering the best balance between stability and handoff triggering delay. NDIST, while not achieving the top results, demonstrates solid association stability without significantly increasing handoff delay. The article also discusses the assumptions underlying each mechanism's design, highlighting the importance of understanding RSSI distribution characteristics. The conclusions suggest areas for future research, including a more in-depth analysis of RSSI distribution and the automatic adjustment of algorithm parameters. This detailed exploration of RSSI filtering mechanisms offers valuable insights for professionals seeking to enhance network performance in dense wireless environments.