I've built a few systems for low-cost airlines in South America. There shouldn't be a lot of difference with bigger airlines around the world. The boarding sof

I've built a few systems for low-cost airlines in South America. There shouldn't be a lot of difference with bigger airlines around the world. The boarding software usually checks that: - The boarding pass is valid (checksum) - The flight state is correct e.g. 'boarding' and 'open' - The passenger did check-in - The passenger haven't boarded yet More advanced implementations can match the gate with the flight, this is optional. The beep usually is a response from the reader indicating that the code has been read successfully. The result of the operation is displayed in a screen and the attendant has to read it and act accordingly.