System/System Interaction
uFirst level of the taxonomy
ØSystems and the interactions between them
ØTraditional (pre-SOA) practice of providing database
links between systems is
intellectually unsound.
ØSystems should be isolated from the ways in which they communicate.
uMany systems can be isolated into several systems that have their inter-system communication separated
out.
ØExample: Human Resources system
§Users fill out images of paper forms on their computers
that are then uploaded
into the database.
§Each form can be considered as an isolated system that
generates an XML
file.
§These files are then sent to the main system for
processing. In this way, the logic of the forms is isolated from the rest of
the system.