Passive On-Line In-Band Interference Inference in Centralized WLANs
In this paper, the authors describe a passive on-line method for determining the conflict graph in a centralized wireless LAN. The key insight in the work is to exploit the relative timing between successfully received frames: If two successful frames sent on two different links overlap in time, then the corresponding links do not interfere; if they are consistently adjacent, then those links do interfere. The scheme is in-band and does not require additional monitoring hardware, nor does it require any modifications to clients. In contrast to recent work that has focused on partial on-line estimation of conflict graphs (restricted to downlinks from APs to clients), the approach can detect the complete conflict graph (both uplinks and downlinks).