In very broad terms, system integration is the process of connecting different sub-systems (components) into a single larger system that functions as one. With regards to software solutions, system integration is typically defined as the process of linking together various IT systems, services and/or software to enable all of them to work functionally together.
- Vertical Integration: Subsystems are integrated according to functionality by creating “silos” of functional entities, beginning with the bottom basic function upward (vertical). This very quick method only involves a few vendors and developers but becomes more expensive over time because to implement new functionalities, new silos must be created.
- Star Integration: Also known as “Spaghetti Integration” because each subsystem is connected to multiple subsystems, so that the diagrams of the interconnections look like a star. However, the more subsystems there are, the more connections are made, and it ends up looking like spaghetti.
- Common Data Format: Helps the system avoid having the adapter convert to and from every application format. Systems using this method set a common or application-independent format, or they provide a service that does the transformation to or from one application into the common application.