In the previous pattern, we assumed that the data moves in one direction; one application prepares the data and another uses it. What if the data traffic is more complex?
Consider an organization that does a lot of sales. Dozens of people in the sales department are on the phone every day following leads that can come from different locations. They can exchange the leads or even follow up with someone else's leads of complete sales started by another person. The organization uses many different applications:
A lead management application: This application keeps all information about leads and ongoing sales from the opportunity to the completed sale stage. The lead management server can be accessed remotely when an employee is on the move.
A customer relationship management application: This is used for maintaining all information about customers, from their name and address to their product preferences and communication notes.
A Bookkeeping and accounting application: This...