Abstract: A processing device such as a server implementing smart building agent functionality is located on an external network and is configured to communicate with a BAS located on a building's internal network. Communication between the processing device and the BAS occurs over a first communications channel. The processing device can be configured to receive sensor data from various sensors that might otherwise not be supported by the existing BAS. Communication between the sensors and the processing device occurs over a second communications channel different from the first communications channel. The processing device can generate control commands based on the received sensor data that provide instructions to the BAS for adjusting an operation parameter for one or more of the building systems and/or equipment. This control command can be sent to the BAS through the first communications channel.