We have concept of VM or virtual box which is nothing but a virtual machine having a specified OS without the actual hardware, rather running it under another OS which reduces cost of buying a new hardware.
On the similar lines we have the concept of Network Function Virtualization or vEPC where we have a single hardware most probably a cloud system serving as a EPC or EPC specific nodes for different vendors and providers.
But above explanation is a very crude explanation where reality is much more complex. I would suggest to go through the following link (there are many other architecture and links for the similar needs which can be checked on internet) which describes the architecture in more detail and comeup with specific query. (And you can publish an article if you like people will appreciate)
http://www.cyaninc.com/solutions/use-case/nfv-orchestration-vepc
