ADWISER: A Controller for Optimum Multi Access Point Coordination and QoS Management in Wi-Fi Networks

We design and implement multi-access point (AP) coordination in a wi-fi network, using fine-grained overlay time-slicing, centralised queueing, and link activity scheduling. Our approach achieves network-wide utility optimal downlink and uplink TCP (transmission control protocol) throughputs, while permitting rate guarantees to designated TCP flows. We also obtain significant improvement in performance of the downlink streaming video, in the presence of co-channel interference from other APs.

ADWISER is a central scheduler through which all downlink and uplink traffic passes; it overlays periodic time-slices, during which sets of AP-STA links are scheduled. During the time-slices, the scheduled AP-STA links use the default IEEE 802.11 PHY/MAC mechanisms; thus, ADWISER works without any modifications to the APs and the STAs. The techniques that we develop and implement perform fine-grained time-slicing, down to 20 ms, thus permitting the handling of delay sensitive internet applications. ADWISER only needs to know the AP-STA associations. By a process of scheduling and measuring throughputs, using stochastic approximation algorithms, ADWISER dynamically determines the set of AP-STA links to schedule in successive time-slices, thereby achieving global network utility optimal throughputs. We have implemented ADWISER on a Linux OS based server machine, and all performance results we report are from test-beds that use commercial off-the-shelf APs and laptops as STAs.

Publications

1.        Vishal Sevani, Purushothaman Saravanan, S.V.R. Anand, Joy Kuri, and Anurag Kumar, “Time-Slicing High Throughput WiFi Networks Using Centralized Queueing and Scheduling,” WiTECH workshop in Mobicom 2022, Sydney, Australia October 2022.

2.        Shivam V. Vatsa, Anusha G. P., Vishal Sevani, Purushothaman Saravanan, Rahul Nair, Rishabh Roy, S. V. R. Anand, Joy Kuri, Anurag Kumar, “Optimum MultiAP Coordination in Wi-Fi with Overlay Time-Sliced Scheduling,” IEEE/ACM Transactions on Networking, accepted for publication in September 2025

Patents

1.        Shivam V. Vatsa, Anusha G. P., Vishal Sevani, Purushothaman Saravanan, Rishabh Roy, S. V. R. Anand, Joy Kuri, Anurag Kumar, “Method and System for Providing Multiaccess Point Coordination in a Wireless Network,” Indian Patent No. 570851, granted 18 September 2025.