Secure API Gateway Architecture for Open Banking
DOI:
https://doi.org/10.15680/9bpqvw75Keywords:
Open Banking, API Gateway, API Security, OAuth 2.0, OpenID Connect (OIDC), Zero Trust Architecture, JSON Web Token (JWT), Mutual TLS (mTLS), Identity and Access Management (IAM), Financial APIs, Cybersecurity, API Management, Threat Detection, Rate Limiting, Encryption, Microservices, Cloud Computing, Regulatory Compliance, PSD2, Real-Time Monitoring, Digital Banking, Secure Financial ServicesAbstract
Open Banking has transformed the financial services landscape by enabling secure, standardized data sharing between banks, fintech organizations, merchants, and third-party providers (TPPs) through Application Programming Interfaces (APIs). While this ecosystem fosters innovation, financial inclusion, and customer-centric digital services, it also expands the attack surface for cyber threats such as unauthorized access, API abuse, credential theft, distributed denial-of-service (DDoS) attacks, and data leakage. Consequently, designing a secure, scalable, and resilient API Gateway Architecture has become a fundamental requirement for protecting sensitive financial transactions while maintaining regulatory compliance.
This paper presents a generalized Secure API Gateway Architecture for Open Banking that integrates modern security mechanisms including OAuth 2.0, OpenID Connect (OIDC), mutual Transport Layer Security (mTLS), JSON Web Tokens (JWT), API rate limiting, threat detection, encryption, centralized logging, and Zero Trust security principles. The proposed architecture illustrates how API gateways serve as the central enforcement point for authentication, authorization, policy management, traffic orchestration, and real-time monitoring across distributed banking services and cloud-native environments. Additionally, the article discusses security controls, API lifecycle management, regulatory considerations, performance optimization, and emerging technologies such as Artificial Intelligence (AI)-driven anomaly detection and behavioral analytics for proactive threat mitigation.
The proposed framework aims to improve confidentiality, integrity, availability, scalability, and operational resilience while simplifying secure API consumption by fintech partners and digital banking applications. By adopting a layered security architecture, financial institutions can accelerate digital transformation initiatives, enhance customer trust, and ensure compliance with evolving regulatory standards. The generalized architecture presented in this paper is intended to serve as a practical reference for researchers, architects, financial institutions, and technology providers developing next-generation Open Banking platforms.
References
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