Printing method, image forming apparatus, and image forming system

An image forming apparatus comprising:

• a scan processing section that scans a first analog document, which is a portable document printed on a medium, to acquire first scan data;
• a storage processing section that stores authentication information authenticated by a user authentication process and a hash value of the first scan data in the first scan data to generate first electronic document data;
• a registration processing section that issues a request for registering the first electronic document data as a first transaction to a blockchain management server;
• and
• a print processing section, wherein
• the print processing section is configured to, when a print execution instruction for the first electronic document data is acquired,
• acquire first transaction information indicating the first transaction from the blockchain management server, based on the hash value stored in the first electronic document data,
• determine whether or not the first electronic document data is tampered with based on the first transaction information, and
• print an image indicated by the first scan data, based on a result of the determination.

An image forming system comprising:

• an image forming apparatus;
• and
• a blockchain management server coupled to the image forming apparatus, wherein
• the image forming apparatus includes
• a scan processing section that scans a first analog document, which is a portable document printed on a medium, to acquire first scan data,
• a storage processing section that stores authentication information authenticated by a user authentication process and a hash value of the first scan data in the first scan data to generate first electronic document data,
• a registration processing section that issues a request for registering the first electronic document data as a first transaction to the blockchain management server, and
• a print processing section,
• the print processing section is configured to, when a print execution instruction for the first electronic document data is acquired,
• acquire first transaction information indicating the first transaction from the blockchain management server, based on the hash value stored in the first electronic document data,
• determine whether or not the first electronic document data is tampered with based on the first transaction information, and
• print an image indicated by the first scan data, based on a result of the determination, and
• the blockchain management server includes
• a server-side registration processing section that registers the first electronic document data as data of the first transaction in response to the request, and
• an information transmission section that returns the first transaction information to the image forming apparatus in response to a request for acquiring the first transaction information from the image forming apparatus.