Profibus and Profinet sound like you are dealing with a Siemens plc. Generally speaking, the internal communication bus of the equiqment is independent from a SCADA connection.
Profinet is a fieldbus protocol that uses standard ethernet cabling and equiqment. Every modern siemens plc has a Profinet / Ethernet port. This port can be used to connect the plc to a Scada like Ignition.
But if a Profinet fieldbus is connected to that port, it should not be connected directly to your companies ethernet. At least a firewall is necessary to protect the profinet from incoming network spam. There are also security risks, but that is another subject.
So, if the Profinet port of the plc is already used as a fieldbus port, it is the best and safest solution to add an additional ethernet communication card to the plc and connect Ignition to that card. There are also processors with a second ethernet conection on board.
Ignition offers a driver for Siemens plcs, but that driver supports only an outdated legacy protocol. If the equiqment manufactureres meets Siemens programming guidelines, you will not be able to use that driver with a new equiqment.
An alternative option is a third party OPC-UA server or a processor with an on-board OPC-UA server. The connection from this on-board server should of course be physically seperated from a possible profinet fieldbus.
Sorry if this is too much information, but there is no simple answer to your question.