What the ISO 20022 Business Application Header (head.001) is and why it matters, covering the routing envelope that accompanies every business message, its fields, its signature, and the head.002 business file header that groups many messages.
2026, Jul 17 — 8 minute read
A guided tour of ISO 20022's auth (authorities) business area, the regulatory-reporting messages that carry MiFIR, EMIR, SFTR, money-market, CCP, and settlement-fails data from firms and infrastructures to their competent authorities.
2026, Jul 17 — 8 minute read
How ISO 20022 models the management of automated teller machines through the caam business area, covering device control, key download, diagnostics, configuration, reconciliation, and exception handling between an ATM and its manager.
2026, Jul 17 — 6 minute read
How ISO 20022 models ATM card transactions through the catp business area, covering the withdrawal, deposit, transfer, inquiry and PIN management flows between an ATM and its host, and the message-level encryption and MAC that protect them.
2026, Jul 17 — 11 minute read
How ISO 20022 models the acquirer-to-issuer card rails through the cain business area, the modern successor to ISO 8583, covering authorisation, clearing, reversal, retrieval, and chargeback between an acquirer and an issuer.
2026, Jul 17 — 9 minute read
How ISO 20022 models the merchant-terminal-to-acquirer leg of a card payment through the caaa business area, covering authorisation, completion, cancellation, reconciliation, currency conversion, and batch transfer.
2026, Jul 17 — 7 minute read
A technical explanation of Ouroboros, Cardano's Proof-of-Stake consensus protocol. Covers epochs and slots, VRF-based slot-leader election, the stake snapshot, chain selection, KES keys, the reward model, and finality.
2026, Jul 16 — 11 minute read
