So ARPANET had a famous "Flag Day" where they switched over to TCP/IP in 1983; it required a simultaneous switchover of all host machines to the new protocol. And I know that "flag day" has since referred to big changes like that in networked systems. I assumed the name referred to some bitwise flags set in packet headers. Turns out, the term comes from Multics, when similar coordination was required for an encoding change. It happened on actual US Flag Day 1966!
https://en.wikipedia.org/wiki/Flag_day_(computing)
Darius Kazemi
npub1fd…rf2f9
2025-07-18 18:45:35 UTC
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wss://relay.momostr.pinkPublished at
2025-07-18 18:45:35 UTCEvent JSON
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