The various embodiments provide systems, devices, and methods which include an acoustic tag configured to transmit an acoustic signal through a contact medium that may be received by an acoustic modem, with the acoustic signal configured to transmit information. By modulating sound traveling through an acoustic connection between the fluid container and a pump, meter or valve, information such as an identifier of the fluid or container may be transmitted without risk of confusion with other fluid containers in the vicinity. In a medical embodiment, IV fluid and the IV drip tube provide a fluid and plastic acoustic connection to an IV pumping or metering device and an IV bag through which sound may be transmitted. The transmission of identification information through this physical connection may insure that the pumping or metering device only communicates with the IV bag coupled to the pump. Acoustic tags may be active or passive.