Methods and apparatus for control using control devices that provide a virtual machine environment and that communicate via an ip network

A system, comprising:

• a controller coupled for communication over a control network operating in an Ethernet protocol;
• a powered Ethernet interface coupled to the control network;
• a sensing apparatus adapted to sense a physical condition and coupled to the powered Ethernet interface for communicating about the sensed physical condition with the controller,
• wherein the powered Ethernet connection provides power to the sensing apparatus.

A system, comprising:

• a controller coupled for communication over a control network operating in an Ethernet protocol and adapted to transmit control signals over the control network;
• a powered Ethernet interface coupled to the control network;
• and
• a field device that comprises any of:
• (i) a positioner coupled to the powered Ethernet interface for receiving control signals from the controller and drawing power from the Ethernet interface, and
• (ii) an actuator adapted to control a mechanism to affect the physical condition of an environment and coupled to the powered Ethernet interface for receiving control signals from the controller, the actuator adapted to draw power from the Ethernet interface.

A transmitter device, comprising:

• an Ethernet interface configured to communicate over a network according to an Ethernet protocol;
• power circuitry operable to extract operating power from the Ethernet interface;
• a sensor interface configured to communicate with a sensing device adapted to sense a physical condition;
• a processor operable to receive a sensing device communication corresponding to a sensed physical condition and to communicate with a control device via the Ethernet interface about the sensed physical condition.