This solution calls for a Message Bus pattern. This subject is introduced in the book Enterprise Integration Patterns (Hohpe, Woolfe):
An enterprise contains several existing systems that must be able to share data and operate in a unified manner in response to a set of common business requests.
The authors go on to say:
An enterprise often contains a variety of applications that operate independently but must work together in a unified manner. Enterprise Application Integration (EAI) defines a solution to this problem but doesn't describe how to accomplish it.
Many companies that increase in size due to organic or acquisition growth find themselves in a position where the new enterprise consists of a large number of disparate ...