An apparatus and method to detect consumer choices of products by use of RFID tags associated with a product and RFID readers to detect movement of the tag, which can initiate a presentation of relevant digital media based on the event and tag detected. A current flowing through the differential amplifier circuit is controlled by a current source, a current value of which is changed depending on the voltage of the non-inverting input terminal. The one or more packet switches route the data packets to one or more intended destination computing nodes and also transmit a copy of all the data packets received in the data communications network to a network capture device. This provides a timely yet secure way for a customer to allow a service provider access to system resources which requires neither a standing open account nor manual opening and closing of a user account for the service provider.