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cbhl

How does this work? I assume it's not just ntp over TCP/IP/Wi-Fi...

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Probably just the wifi TSF: https://en.wikipedia.org/wiki/Timing_Synchronization_Functio...

Notably used by the Wii U: https://patchwork.kernel.org/patch/5865651/

TSF is not scalable[0].

[0] http://web.cse.ohio-state.edu/~lai/788-Au03/2-scalibility.pd...

I should have mention this only applies to IBSS (ad-hoc), not to (infra) BSS, where the AP sends the beacon

>On a commercial level, industry vendors assume the 802.11 TSF's synchronization to be within 25 microseconds.

Meh. Still cool, but a far cry from the sub-MICROsecond accuracy the page suggest, which would indeed be quite revolutionary.

I'm curious which are the use cases for sub-microsecond time sync. Entertainment can probably do with millisecond accuracy. Other use cases mentioned by the Wifi Alliance preso are healthcare, industrial, automotive, and IoT. Do you know any precise use cases?

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