The Open Banking TPP REST service uses HA Proxy, a HSM, Database Server and an API Gateway to connect PSUs to their ASPSPs
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Open Banking is deployed on a highly secure, monitored and hosted service.

The service is built on:

HA Proxy The SSL Termination
API Gateway Managing throttling, Idempotency, Load balancing and API Security
TPP-REST The Nuapay TPP Platform
HSM A Hardware Security Model, storing private keys, etc.
Database Server Storing transaction details and audit trails
ASPSP The Account Servicing Payment Service Provider (the bank in which PSUs hold an account)
Deployment Overview
Deployment Overview