I would use Task Manager on those machines, and sort by the "network" column.  Then you can isolate it down to an individual process using the traffic. Otherwise, there are so many things it could be. ... View more

Hi Guys,   My team and I just checked the categories again and I can confirm that the categories that I posted on 1/24/2018 are still active and available to use with your Cisco Meraki equipment. ... View more

Note that this also means that your PLC's won't be able to initiate connections to the "machine". This is fine if all communication is initiated from the "machine" (because the firewall is stateful), but if not, you're better off doing what @jdsilva said. E.g. PLC needs to get a new firmware over TFTP from the "machine". ... View more