Before virtualization, when it came to corporate computing, companies kept their data in a box. When someone needed the data, a request was sent out over the network and routed to that box. The information was then sent back over the same path. This isn’t the most efficient way of keeping data, but since data mapped to a box, it was secure. Corporations liked that.
But as boxes became more powerful, the amount of processing power they had and work they did didn’t really take advantage of that improvement in performance. So some companies virtualized the hardware, making one box look like many virtual machines. New technologies made it easier to track what data was stored on these virtual machines, and security was maintained because the data stayed in these virtual machines. And with many virtual machines on them, the powerful servers were being used more fully. Again, corporations liked that.
But the corporations weren’t happy for long. Even though there were many virtual machines processing data on these servers, there was still only one network. In order for each request to get to the right VM, the network had to know where that virtual machine was located. But virtualization had changed servers from single-family homes into apartment buildings. And like apartment renters, those virtual machines can move around fairly easily. When those VMs move, the network needs the equivalent of a change of address form, but that means an IT administrator has to replace a card or reroute a cable. Requiring a person to intervene in what should be an automatic process, wastes time and costs money. Corporations hate that.