Legacy-Compatible Multi-User Wi-Fi Aggregation for Enhanced Downlink Efficiency and Security

This work introduces a novel Wi-Fi frame aggregation mechanism that enables efficient multi-user downlink transmissions in IEEE 802.11 networks (including earlier standards). We focus on exploring feasible and practical approaches to enable or approximate multi-user aggregation by leveraging existing features, while ensuring the compatibility with legacy standards. The proposed approach, implemented and evaluated on a real-world testbed, allows the Access Point (AP) to aggregate MAC Service Data Units (MSDUs) destined for multiple users/stations, using a scheme based on Multichannel Broadcast Encryption of Short Messages. It is particularly effective in scenarios involving a high volume of small data packets to multiple users/stations and where communication reliability is critical to maintaining high-quality service. This innovative solution not only extends and improves the efficiency of standard aggregation schemes in such scenarios but also enables efficient multi-user downlink transmissions and enhances security by strengthening the protection of transmitted data.