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by dingo_bat 3343 days ago
But then how do they recall contaminated pouches?
1 comments

Depends.

If it’s contaminated ‘coz expired, it’s doable. Many devices have accurate real-time clocks even offline, e.g. GPS. It’s easy to include the expiry date in that cryptographically-signed data. BTW, Kerberos protocol does similar things with their timestamps.

If however it’s contaminated just because the producer decided to recall a batch of their product, then yes, a centralized server is a good choice.