GoKawiilHow JR East's Suica IC Card Processes Fare Payments Offline in Under 200ms
Suica, Japan's IC transit card developed in the 1990s, stores a card ID and balance directly on its chip rather than relying on a central server. Each tap triggers a local read-write transaction with mutual authentication and a fresh encryption key, completed in under 200 milliseconds, all without a battery, powered instead by the electromagnetic field from the station reader.