From Milliseconds to 26 Nanoseconds: How a $20 eBay SFP Module Beat My Entire NTP Setup Wallabag: https://read.hostux.net/share/69f21c8b3956f2.13434727 Source : https://austinsnerdythings.com/2026/04/26/ptp-osa5401-26-nanoseconds-raspberry-pi/