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Labs

Interactive experiments that go with our deep dives. Pick a lab, step through the concepts, and see how things actually work under the hood.

3-D Secure Decision Tree

Simulate issuer ACS decisions across frictionless authentication, challenge flows, exemptions, soft-decline retry, liability evidence, and checkout state.

systemsbankingsecurity

ATM Network Message Path

Trace a cash withdrawal through the ATM, acquirer switch, scheme network, issuer, dispenser, journal, reversal path, and settlement.

systemsbankingatmpayments

Bank Reconciliation Queue

Match internal ledger entries to external statement lines, classify amount and reference breaks, age unresolved items, and close controlled repairs.

systemsbankingledgers

Sharded Ledger Contention Simulator

Move payment requests across ledger shards, hot accounts, replay guards, posting queues, cut-off jobs, and reporting snapshots.

systemsbankingscalabilityledgers

Card Payment Sequence

Follow one purchase from POS terminal through acquirer, scheme network, issuer authorisation, clearing, settlement, and merchant funding.

systemsbankingcards
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