Coordinated SR and Restricted TWT for Time Sensitive Applications in WiFi 7 Networks

The main focus of every new WiFi generation has been to increase the overall network throughput capabilities. This paradigm changed somewhat with the introduction of WiFi 6, where new features were introduced that, in addition to throughput increase, dealt with improving the efficiency of resource usage and channel access as well. These features included uplink/downlink orthogonal frequency-division multiple access (UL/DL OFDMA), UL/DL multi-user multiple-input and multiple-output (MU-MIMO), and basic service set (BSS) coloring. With the advent of WiFi 7, also known as IEEE 802.11be, more coordination is foreseen between different access points (APs), bringing the possibility to support time-critical traffic in wireless networks as well. Boosted coordination between APs improves the throughput under dense deployed WiFi networks, as well as giving support for prioritized channel access for certain devices and traffic flows. In this article, we will review coordinated spatial reuse (C-SR) and restricted target wake time (R-TWT) as two features that are going to be introduced in WiFi 7. Further, this article shows conceptually how the C-SR feature can be implemented in practice. We show the results of a real implementation of both features (C-SR and R-TWT) on top of the openwifi open-source software-defined radio platform.