LGB Bank: Composite microservices in a large global bank (D)

• Main Authors: MEGARGEL, Alan, POSKITT, Christopher M.
• Format: text
• Language: English
• Published: Institutional Knowledge at Singapore Management University 2021
• Subjects: Service Reuse; Enterprise Architecture; Service-Oriented Architecture; Microservices; Atomic Microservices; Databases and Information Systems; Entrepreneurial and Small Business Operations
• Online Access: https://ink.library.smu.edu.sg/cases_coll_all/390; https://smu.sharepoint.com/sites/admin/CMP/cases/SMU-21-BATCH%20%5BPDF-Pic%5D/SMU-21-0037%20%5BLGB%5D/SMU-21-0037D%20%5BLGB%20D%5D.pdf?CT=1639549030975&OR=ItemsView
• Institution: Singapore Management University

This case study is organised into four parts (A through D), meant to be read and discussed progressively. Jane Blanston, a newly hired Enterprise Architect at LGB Bank, had developed over her career a specialisation in Service-Oriented Architecture (SOA). Prior to joining LGB, she had recent successes in a smaller regional bank where she had replaced its outdated batch-mode file transfer style of integration with a real-time SOA style of integration. This provided the bank with a more flexible architecture and an abstraction layer which enabled the bank to make large scale changes in the backend (e.g., a core banking system replacement) with minimal impact to the bank’s front-end banking channels (e.g., internet banking). Furthermore, with an SOA in place, the bank had the ability to rapidly assemble new solutions by reusing existing services. Blanston was headhunted by LGB and offered a job based on her expertise in SOA and reputation as a problem solver. LGB specifically wanted her to review its current microservices-based architecture (a subset of SOA) and to propose an improved architecture which emphasised service reuse, like what she had implemented in the past. Even though LGB was a larger bank with larger integration problems, She decided to take up the challenge. She accepted the job offer to join LGB’s technology department based in Singapore. This case study gives students an opportunity to learn how an existing enterprise system can be refactored into a modern microservices-based solution that increases the reusability and automatability of a key business process. Students will follow Blanston’s thought process as she replaces an archaic and multi-day batch processing solution with one that is automated by an assembly of composite microservices, including aggregation and orchestration patterns. The case is organised into four parts to gradually introduce aggregation, orchestration, SOA layers, and conceptual diagrams.