Method and apparatus for managing subject data based on block chain

1. A block-chain-based subject data management method, the method comprising:

creating subject data on a node in accordance with a request of a user device;

creating first metadata related to the subject data;

creating a first block including the first metadata;

storing the first block in a block chain included in the node;

creating a first code by coupling hash information of the subject data and a time stamp when the subject data is created;

storing the first code in the node; and

transmitting the subject data and the first code to an off-chain database,

wherein the subject data is stored in the off-chain database,

creating second metadata related to a modified subject data when the subject data stored in the off-chain database is modified;

creating a second block including the created second metadata to store the second block in the block chain;

creating a second code based on hash information of the modified subject data;

storing the created second code in the node; and

transmitting the modified subject data and the second code to the off-chain database,

wherein the first code stored in the node is mapped to an address of the off-chain database in which the subject data is stored and the second code stored in the node is mapped to an address of the off-chain database in which the modified subject data is stored.

2. The method according to claim 1 , wherein when the subject data is modified, the address information of the off-chain database in which the modified subject data is stored is modified to the address information including the second code.

3. The method according to claim 1 , further comprising:

creating a first smart contract related to right assignment or ownership transfer with respect to the subject data;

creating a third block including the created first smart contract to store the third block in the block chain;

performing an operation for the right assignment or ownership transfer corresponding to the contract contents of the smart contract when an operation corresponding to the contract condition of the first smart contract is performed; and

creating a fourth block including information on a fulfilled contract history or a fulfilled contract result of the first smart contract to store the fourth block in the block chain.

4. The method according to claim 3 , wherein the first smart contract includes information on an electronic wallet address of a user, the contract condition, and the contract contents performed when the contract condition is satisfied and the first smart contract further includes information on the electronic wallet address of a contract subject.

5. The method according to claim 1 , further comprising:

inquiring a second smart contract for a contract related to the subject data;

performing an operation corresponding to the contract contents of the second smart contract when an operation corresponding to the contract condition of the inquired second smart contract is performed; and

creating a fifth block including information on a fulfilled contract history or a fulfilled contract result of the second smart contract to store the fifth block in the block chain.

6. A block-chain-based subject data management apparatus, comprising:

a communication unit;

a storing unit configured to store a block chain; and

a processor which is configured to be operably connected to the communication unit and the storing unit, wherein the processor is configured to:

create subject data in accordance with a request of a user device;

create first metadata related to the subject data;

create a first block including the first metadata;

store the first block in a block chain in the storing unit;

create a first code by coupling hash information of the subject data and a time stamp when the subject data is created;

store the first code in the storing unit;

transmit the subject data and the first code to an off-chain database,

wherein the subject data is stored in the off-chain database,

create second metadata related to a modified subject data when the subject data stored in the off-chain database is modified;

create a second block including the created second metadata to store the second block in the block chain;

create a second code based on hash information of the modified subject data;

store the created second code in the node; and

transmit the modified subject data and the second code to the off-chain database,

wherein the first code stored in the node is mapped to an address of the off-chain database in which the subject data is stored, and the second code stored in the node is mapped to an address of the off-chain database in which the modified subject data is stored.

7. The apparatus according to claim 6 , wherein when the subject data is modified, the address information of the off-chain database in which the modified subject data is stored is modified to the address information including the second code.

8. The apparatus according to claim 6 , wherein the processor is further configured to:

create a first smart contract related to right assignment or ownership transfer with respect to the subject data;

create a third block including the created first smart contract to store the third block in the block chain;

perform an operation for the right assignment or ownership transfer corresponding to the contract contents of the smart contract when an operation corresponding to a contract condition of the first smart contract is performed; and

create a fourth block including information on a fulfilled contract history or a fulfilled contract result to store the fourth block in the block chain.

9. The apparatus according to claim 8 , wherein the first smart contract includes information on an electronic wallet address of a user, the contract condition, and the contract contents performed when the contract condition is satisfied and the first smart contract further includes information on the electronic wallet address of a contract subject.

10. The apparatus according to claim 6 , wherein the processor is further configured to:

inquire a second smart contract for a contract related to the subject data;

perform an operation corresponding to the contract contents of the second smart contract when an operation corresponding to the contract condition of the inquired second smart contract is performed; and

create a fifth block including information on a fulfilled contract history or a fulfilled contract result of the second smart contract to store the fifth block in the block chain.