ICAI eBook Portal System Flow implements a dual-path authentication architecture combining SSO and OTP verification to gate access to a secured digital library. Users authenticate via either SSP SSO API validation or email-based OTP, with failed credentials triggering Access Denied branches and successful validation routing to the Secured Portal Dashboard. The portal integrates Advanced Search powered by Elastic Index for keyword highlighting, and eBook Flipbook Reader with DRM Layer protection and Secure PDF Stream delivery using temporary session URLs to prevent unauthorized print and download. This architecture demonstrates defense-in-depth for intellectual property protection while maintaining frictionless user experience for authenticated members.