Messaging Middleware - Large enterprises generally expend about ¼ of their entire IT budget on the systems and processes to connect the disparate systems that make up complex application stacks.

When you look at how business processes are architected, they nearly always make use of a myriad of different infrastructure elements, platforms and applications, and these are all interconnected using an array of messaging middleware systems that ensure that every single request is processed even when the capacity and performance of some components causes requests to be stacked in queues.