Assume I have two different software sub systems and I need to interconnect them through an Enterprise Service Bus.
What sort of modifications do I need to make in the existing systems to integrate this ESB?
For example assume vendor A developed System A, and vendor B developed system B. In order to make these two communicate with each other through an ESB what should vendor A developers do, and what should vendor B developers do?
This is what I have understood so far.
In order to connect to the ESB, system A acts as a web service client and the ESB acts as a web service provider. Then the ESB forwards the message to the system B after mediating the message as needed.
For this to work the existing systems need to be modified to act as web services clients and web services. All the systems can expose their needed functionality as web services and when messages needs to be sent they should act like clients. So there needs to be some modifications done in both systems. Correct me where I am wrong.