Image forming system, image forming apparatus, and image forming method that allows to pull print without server

An image forming apparatus comprising:

• an identification information acquisition part configured to acquire identification information of document data for pull print;
• a block acquisition part configured to acquire a block, into which the document data is divided, corresponding to the identification information acquired by the identification information acquisition part from other apparatus;
• a document reproduction part configured to pack and decrypt the block acquired by the block acquisition part;
• an image forming part configured to output the document data decrypted by the document reproduction part;
• and
• a storing and transmitting part configured to transmit the block to at least two preserving apparatuses,
• wherein the storing and transmitting part
• decreases priority of transmission of the block to a preserving apparatus that is likely to be in an offline state,
• increases the priority of transmission of the block to a preserving apparatus that has high processing capacity and/or new installation years, and
• suppresses transmission of the block to a preserving apparatus that is expected to be in error.

An image forming method executed by an image forming system having a transmitting apparatus, a plurality of preserving apparatuses, and an output apparatus and allowing to pull print, comprising the steps of:

• by the transmitting apparatus, generating identification information of a document data for the pull print, dividing into blocks, calculating and including a previous hash value of a previous block in order, and generating a blockchain of the document data;
• by the transmitting apparatus, transmitting each of the divided blocks to at least two of the plurality of preserving apparatuses;
• by the plurality of preserving apparatuses, storing a block received from the transmitting apparatus;
• by the output apparatus, acquiring the identification information of the document data;
• by the plurality of preserving apparatuses, transmitting the block stored in the respective preserving apparatus according to the instructions from the output apparatus;
• by the output apparatus, acquiring each of the blocks corresponding to acquired identification information from any one of the preserving apparatuses;
• by the output apparatus, packing each of the acquired blocks and reproducing to the document data;
• and
• by the output apparatus, outputting the reproduced document data.