Unison Systems provides experienced Systems Integrators who begin our comprehensive SI practice by analyzing
your entire IT ecosystem. Our systems integration methodology of linking together different, and often
disparate, computing systems and software applications ensures the interoperability of aggregated subsystems so
that the end state architecture is able to deliver the expected over-arching functionality.
Our systems integration approach provides three main styles of integration:
Vertical Integration is the process of integrating subsystems according to their functionality by creating functional
entities also referred to as silos. The benefit of this method is that the integration is performed quickly and involves
only the necessary subsystem so this method is cheaper in the short term. On the other hand, cost-of-ownership can be
substantially higher than seen in other methods, because in cases requiring new or enhanced functionality, the only
possible way to implement (scale the system) would be by implementing another silo.
Star Integration is a process of integration of the systems where each system is interconnected to each of the remaining
subsystems. When observed from the perspective of the subsystem which is being integrated, the connections resemble a star.
The cost varies depending on the interfaces which subsystems are exporting. In a case where the subsystems are exporting
heterogeneous or proprietary interfaces, the integration cost can substantially rise. Time and costs needed to integrate the
systems increase exponentially when adding additional subsystems. From the feature perspective, this method often seems
preferable, due to the extreme flexibility of the reuse of functionality.
Horizontal Integration or Enterprise Service Bus (ESB) is an integration method in which a specialized subsystem is dedicated
to communication between other subsystems. This allows cutting the number of connections (interfaces) to only one per subsystem
which will connect directly to the ESB. The ESB is capable of translating the interface into another interface. This allows
cutting the costs of integration and provides extreme flexibility. With systems integrated using this method, it is possible to
completely replace one subsystem with another subsystem that provides similar functionality but exports different interfaces,
while remaining completely transparent for the rest of the subsystems. The only action required is to implement the new interface
between the ESB and the new subsystem.