The world's largest card network, Hungary's largest bank - and a gateway processing 400,000+ transactions daily since 2011

UnionPay International - the world's largest card payment network with 70% Asia-Pacific market share - needed its card-issuing infrastructure connected to OTP Bank's acquirer-side systems in Hungary. The two operated on different protocols with no standard bridge. The integration had to handle 400,000+ daily peak transactions, meet stringent PIN security requirements, and operate under 24/7 SLA with near-zero tolerance for failure.

E-Group built the gateway performing protocol conversion between OTP Bank's acquirer interface and UnionPay's online message interface according to the ISO 8583 standard - eliminating customisation on OTP's side, reducing cost and shortening go-live time. PIN security is handled through an integrated Thales hardware security solution. The gateway supports the full card operation set: authorisation, purchase, refund, pre-authorisation, cash withdrawal, balance enquiry, and cancellation. The same gateway infrastructure also processes payment transactions for Starbucks retail operations across multiple markets.

The gateway has operated continuously since 2011 under a strict service level agreement - 24/7 support and 99.99% system reliability - processing over 400,000 transactions per day at peak. It forms part of one of the world's largest card payment ecosystems, demonstrating E-Group's capacity to build and sustain mission-critical financial infrastructure at the intersection of global and national payment systems.