Abstract: A non-transitory computer readable medium including instructions that, when executed by a processor, perform a method involving: receiving, by a point of sale (POS) system, purchase data for a customer; generating bidirectional connection data for the customer, where the bidirectional connection data describes a bidirectional connection; encoding a symbol with the purchase data and the bidirectional connection data; presenting the symbol to the customer; enabling the bidirectional connection in response to a connection request from the customer; receiving payment data from the customer over the bidirectional connection; comparing the payment data to the purchase data; and sending a payment confirmation to the customer over the bidirectional connection in response to a determination that the payment data satisfies the purchase data.