Improving Wi-Fi performance using Smart AP

Wireless network is constantly expanding due to their superior accessibility and convenience when compared to wired networks. In the meanwhile, as physically limited bandwidth of wireless networks becomes increasingly congested, it is suffering from performance degradation. Although TCP is widely adopted regardless of wired and wireless networks, it is fundamentally designed and optimized for wired networks. Furthermore, recent advances of combo-modules that enable two or more network interfaces to share an antenna introduce a new challenge of Cross Technology Interference (CTI). In this paper, we identified redundant acknowledgement process across multiple layers during TCP transmission, and investigated root causes of interference pattern in combo-modules which induce transmission failures. Then we suggest two novel AP-side solutions called I-ACK (Implicit Acknowledgement) and Smart AP. I-ACK eliminates overhead caused by redundancy in TCP transmission procedure, and Smart AP stands strong against malfunction of combo-modules. We implemented these schemes on off-the-shelf AP and demonstrated the effectiveness in an anechoic chamber where external noise is blocked.