Resilient and Highly Available Payment System Architecture

Business challenge

Our client is one of the largest commercial banks in Europe. Headquartered in Austria, they offer a wide choice of banking services to over 2.5 million customers. The bank has set two priorities in its new growth strategy: embracing digital technologies and becoming a modern and flexible bank. To support their digital transformation effort, the bank’s leadership considered completely revamping the legacy banking ecosystem, including core, complementary, and internal services.

Such a large-scale endeavor required profound technological capabilities and knowledge, which the bank lacked. Therefore, they started a tendering process to develop a payment processing system and invited Intellias along with other top IT services providers from Central and Eastern Europe to participate.

Based on our immense experience developing payment solutions combined with a deep understanding of banking industry specifics, our team designed a payment system architecture that completely met our client’s requirements for availability and resiliency. Our payment system design prompted the bank’s executives to establish a partnership with Intellias as a reliable financial software development services provider.

Solution delivered

Our client entrusted us with a project that has tremendous technological value for the digital transformation of their banking ecosystem. The project focuses on two priorities:

• Replacing a legacy platform with a microservices-based platform as the core for processing all transactions
• Developing twelve independent products and services to meet the needs of enterprise, individual, and internal customers

Intellias is responsible for our client’s payment system design, architecture, and infrastructure. To provide the functionality of such a large software application, we chose a service-oriented architecture (SOA) model as it defines the bank’s business functions as services communicating with each other by exchanging messages. To ensure system interoperability and eliminate service dependency, we use Pub/Sub as a message distributor. Also, with the SOA model, we can combine services developed with new and old technologies, enabling components to integrate and coordinate in an effective and agile manner. Thanks to the flexible integration of all data, the SOA model streamlines platform development, making it more cost-effective compared to other architectural models.

When designing the solution infrastructure, Intellias experts focused on ensuring instant 24/7 payment processing. We developed infrastructure in the Kubernetes ecosystem that allowed us to achieve high system scalability, availability, and resiliency. Also, we introduced Apache Flink as a stream processing engine able to handle an extremely high workload of real-time streaming data with very low latency.

We adopted Istio on Kubernetes, as it simplifies service-to-service network operations like traffic management, authorization, and encryption as well as auditing and observability. To build a robust IT security foundation, we introduced DevSecOps practices that automate security tools, enabling us to identify vulnerabilities in the early stages of the SDLC.

Our client’s payment platform architecture is designed to comply with the ISO 20022 standard that provides more detailed information about a transaction compared to other standards. It enables the bank to eliminate payment delays caused by compliance checks due to poor quality or insufficient data. Also, the system complies with the resilience requirements of central banks.

Business outcome

Using the latest technologies and practices, Intellias is developing an advanced payment processing system architecture that’s the core of our client’s whole banking ecosystem. It has these main characteristics:

• 24/7 availability and 99.741% failure resistance
• High throughput (currently, 3 million transactions in 8 hours)
• Unified API for all business-oriented services
• Unified and well-defined interface for isolating legacy systems

Due to well-thought-out payment processing architecture, the system currently serves nearly 30,000 large and small to midsize enterprise clients, 5 million mobile users, and 7,000 internal users.

By implementing the ISO 20022 message format, our client will not only speed up payments but increase transparency and improve sanctions screening. This means improved compliance with international anti-fraud and anti-money laundering regulations. It also helps our client move towards PSD2 implementation to leverage the benefits of open banking.