The evolution of modern web application architectures has shifted towards decentralized, microservice-oriented patterns that prioritize scalability, security, and maintainability. This thesis details the architectural re-engineering of the PROMET&O platform, a sensor data and survey management system used within the Politecnico di Torino. The pre-existing infrastructure, characterized by redundant localized authentication services and static routing configurations, suffered from significant scalability limitations, security vulnerabilities, and operational inefficiencies. The primary contribution of this work is the migration from a fragmented deployment to a centralized architecture. This was achieved by decoupling the authentication logic from business applications through the implementation of a centralized Identity and Access Management (IAM) system using Keycloak.