Well thank you !
I'm also an electronic engineer, the mechanical stuff is just what I've picked up along the way, and benefitted from some outstanding advice from others to get to where I need to go.
Most of the modules are ARM cortex processors with a bunch of custom I/O surrounding them. I wasn't aware I had mentioned FPGA usage anywhere, but the move from EMU III to EMU IV saw the regular arm processor replaced with a Xilinx Zynq 7010 which is essentially a medium density FPGA surrounding a dual core ARM.
VHDL is what I spend my working day doing to be honest, so it wasn't too much of a stretch. The FPGA section calculates rotational speed, rate of change and angle of all 4 camshafts and the crankshaft accurate to 100th of a degree, and presents them in registers for the processor cores to apply the lookup tables to. They in turn program into the FPGA, starting angles, dwell etc for all the injectors and spark plugs and the FPGA takes care of the micro-precise timing.
I don't think anyone else is taking this approach, Bosch certainly aren't and none of the 3rd party units I have seen do either, but front-loading all the blood sweat and tears makes a lot of the tasks associate with running the engine a lot easier.
I'm not sure why you think I need DMZ in the vehicle networks, the networks in question are CAN based, not IP based so the idea of a DMZ is rather unnecessary - did you have a particular issue you think I should be addressing ?