Apparatus, systems, and methods for communicating data between a controller and a multiplicity of field devices operating in a process plant are provided. The system includes distributed marshaling modules coupled by a head-end unit to I/O cards in communication with the controller. The distributed marshaling modules communicate with the field devices via respective electronic marshaling components converting signals between the field devices and the I/O cards. The distributed marshaling modules are coupled to the head-end unit by a ring communication architecture, such that the distributed marshaling modules may each be located relatively proximate to the field devices to which they are coupled.