How did Apple make this work?? (gPTP over WiFi)

Duration: 21:19

Apple's HomePod minis can pair up into stereo pairs.

But how do they do it?

Resources mentioned in this video:

- HomePod mini: https://www.apple.com/shop/buy-homepod/homepod-mini/midnight

- IEEE 802.1AS: https://www.ida.liu.se/~sohsa65/courses/tsn-course-2021/stds/8021AS-2020.pdf

- AirPlay 2 RS (open source project): https://github.com/lmcgartland/airplay2-rs

- What is gPTP: https://blog.meinbergglobal.com/2024/03/27/what-is-gptp/

- What is PTP: https://en.wikipedia.org/wiki/Precision_Time_Protocol

- Wireshark: https://www.wireshark.org

- HomePod mini intro video: https://www.youtube.com/watch?v=cPakvOuwg48

- MacRumors buyers guide: https://buyersguide.macrumors.com/#Homepod-Mini

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Contents:

00:00 - What did Apple do?

01:22 - How hard can it be?

06:36 - Now there are two

08:30 - Testing a stereo pair

09:46 - Wireshark

10:52 - WiFi snooping with Apple

12:46 - Finding gPTP

15:03 - Timing packets

17:09 - How PTP works

17:55 - Brief look at IEEE 802.1AS and AVB

19:51 - Apple using standards?