What Is SOA?

• First, SOA IS NOT A PRODUCT
• SOA is a common sense approach that is both time and road/track tested software development style for building applications using services available in a network (think Sun Microsystems “The Network is the Computer”)
• These software services are relatively large-grained:
  (like: Fraud Detection, Address Change, Payment Management, Trade Execution) 
• Implementations are shielded by a public interfaces aka services  
• The change to an underlying implementation, should not change the existing interface.
• Services form building blocks of  SOA applications 
• Applications that use these services are called Composite Applications