Trespassing the Walled Garden: Teaching Linux to Speak Apple's Low-Latency WiFi (mrmcd26)

Some boundaries are not imposed by technology itself, but by what remains undocumented. This talk presents our progress toward freeing Apple's Low-Latency WiFi from its walled garden to the open-source world. We reverse-engineer the proprietary communication between macOS and Broadcom's wireless chips in order to reimplement LLW on Linux. The interoperability of Apple's ecosystem is limited by design. Compatibility with third-party devices for features such as Continuity Camera and Sidecar Display is not available for technical reasons, but because the protocol stack is largely undocumented. At [39C3](https://media.ccc.de/v/39c3-cracking-open-what-makes-apple-s-low-latency-wifi-so-fast), we presented the internals of Low-Latency WiFi, the protocol these features rely on for achieving fast data transmissions. LLW turned out to rely on concepts from the widely adopted Wi-Fi standard IEEE 802.11. This talk is about crossing the border of Apple's walled garden. We showcase what's necessary to bring proprietary protocols like LLW to Linux, how to reverse engineer the communication between macOS and the wireless chip, and which parts of Linux need to be extended. Finally, this talk gives an overview of where the LLW reimplementation is currently at and outlook of what's still ahead to make LLW work on open platforms. https://creativecommons.org/licenses/by-sa/4.0/ about this event: https://talks.mrmcd.net/2026/talk/3R8PSJ/