CAPKs: The Cryptographic Trust Anchors Behind Every EMV Transaction
Every card-present transaction begins with a question the terminal must answer before anything else: is this card genuine?
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Payments
What Actually Happens in the 2–3 Seconds of a Card Payment
A card payment feels instantaneous. The system behind it is not.
POS Architecture Beyond Certification: Financial Infrastructure, Fraud Detection, and the Expanding Attack Surface
The POS terminal has quietly become critical financial infrastructure — and most architects are still designing it like a payment endpoint.
Why PIN Still Matters in Card-Present Payments
EMV authenticates the card. PIN still helps authenticate the cardholder.
Scheme-Level Signaling: How Networks Identify Unattended Transactions
PCI PTS classifies devices at the hardware level. But Visa and Mastercard classify transactions at the message level. No scheme inspects the physical terminal to determine whether it is attended or …
Offline EMV vs Store-and-Forward: Two Different Mechanisms, One Confusing Name
When a POS has no connectivity, merchants still need to accept payments. The industry uses terms like “offline transaction” and “offline processing” loosely — but in EMV terms, …