A Scalable Multi-tier Architecture for the National Taiwan University Hospital Information System based on HL7 Standard

This article describes the successful experiences of National Taiwan University Hospital (NTUH) in moving from IBM Mainframe to connected networking computer systems. We use multi-tier architecture and HL7 standard to implement our new outpatient hospital information system (HIS). The NTUH HIS is a complex environment with several operating systems, databases, and information systems. We adopt service-oriented architecture (SOA) to reduce the complex relations between systems and solve data consistency problems among databases. We also show that the distributed architecture can provide us stable and reasonable system performances. Our main contribution is proving that the distributed environment with HL7 standard and SOA can sustain in a highly demanding environment