Transaction system, information processing method, and processing device

A transaction system comprising:

• a POS terminal configured to transmit control data to a processing device instructing the processing device to execute a transaction-related process;
• the processing device configured to:
• receive the control data from the POS terminal,
• execute the transaction-related process based on the control data,
• extract transaction information from the control data,
• generate transaction identification information that identifies the transaction information,
• transmit, to a control device, the transaction information and the transaction identification information, and
• output a code that encodes the transaction identification information;
• a terminal configured to:
• store device identification information in memory of the terminal,
• read the code,
• extract the transaction identification information from the code, and
• transmit to the control device the transaction identification information and device identification information;
• and
• the control device configured to:
• receive from the processing device and store in memory of the control device, as first associated information, the transaction information and transaction identification information,
• extract transaction time information from the transaction information,
• receive from the terminal and store in memory, as second associated information, the transaction identification information and device identification information,
• generate or receive read-time information related to the transaction identification information and device identification information received from the terminal,
• match the transaction identification information of the first associated information and the transaction identification information of the second associated information,
• determine, based on the transaction time information and the read-time information, that a difference in transaction time and read time is within a predetermined range,
• store in the memory of the control device, as associated, the transaction information and the device identification information responsive to the matching the transaction identification information and the determining that the difference in transaction time and read time is within the predetermined range, and
• provide a service based on the associated transaction information and device identification information.