Exploiting multiple links with a single interface: A performance study

The IEEE 802.11 working group is in the final stages of completing the 802.11be amendment, which outlines the features to be supported by Wi-Fi 7 devices. One of the key innovations introduced is Multi-Link Operation (MLO), which enables a device to function across multiple frequency channels simultaneously. Among the various MLO configurations, Enhanced Multi-Link Single Radio (EMLSR) has garnered significant attention from vendors due to its ability to leverage multiple links with reduced hardware complexity.

This paper begins by presenting an overview of the EMLSR specifications as defined in the standard and outlines the implementation model used in the ns-3 simulator, one of the most widely used simulators for wired and wireless networks. The performance of EMLSR operations has not been analyzed in depth so far. To the best of our knowledge, this paper is the first one to offer a theoretical analysis along with a simulation-based evaluation to assess the performance of an EMLSR client. Under saturated network conditions without external interference, the EMLSR client demonstrates throughput performance comparable to – or even exceeding – that of a traditional Single-Link Device (SLD), despite the overhead introduced by MLO functionality. In scenarios with unsaturated traffic and interference, the EMLSR client not only achieves lower latency than an SLD but also matches or outperforms a Multi-Link Device (MLD) with more advanced hardware that operates across multiple links simultaneously.