This Distributed Online Auction System is a high-availability enterprise application built on the Java EE (J2EE) stack and deployed as a scalable Enterprise Archive (EAR) to handle concurrent real-time bidding. The backend architecture utilizes a multi-layered EJB component model, featuring Singleton Session Beans (e.g., AuctionStoreBean) protected by ReentrantReadWriteLocks and AtomicIntegers to ensure thread-safe, centralized state management for auction data , while Stateless Session Beans efficiently handle business logic and transactions through container-managed pooling. Real-time responsiveness is achieved by decoupling bid processing via Java Message Service (JMS) Topics (jms/MyTopic) and Message Driven Beans (MDBs) like AuctionUpdateMDB, which asynchronously consume events and push live updates to the frontend. The presentation layer integrates Servlets and JSP with a responsive user interface built using Bootstrap, jQuery, and JavaScript, communicating via WebSockets to broadcast JSON data serialized with the Jackson library, ensuring all connected clients receive immediate synchronization of bid states and auction creations.