System and methods for enhanced modular controller port to port communication

An enhanced modular controller for a process plant includes two sets of communication ports (201-206, Fig. 2) and a software layer, the software layer applies port communication rules 302-310 to the communication ports such that the retransmission of messages incoming at either set of communication ports is selectively allowed or restricted. The communication ports communicate with one or more nodes of a distributed control system of the process plant. The controller further includes a control logic layer for controlling equipment within the process plant. The enhanced modular controller may further comprise a standard communication port for communicating with a node via a standard communication protocol and a native communication port for communicating with a node via a native communication protocol. The software layer may create or update a virtual local area network (VLAN) lookup table and one or more VLANS associated with the VLAN lookup table, the software layer accessing the VLAN lookup table and the one or more VLANs to selectively allow or restrict retransmission of incoming messages.