Abstract: There is disclosed a website management device including a memory that stores an administrator DID and an administrator private key, a communication interface that communicates with a blockchain network, and at least one processor, and the at least one processor submits a first transaction for creating a URI authentication document to the blockchain network, the first transaction including an administrator digital signature created based on the administrator private key, the first URI, and an access rule for data included in the first URI, and retrieves a remittance transaction having a blockchain account on the blockchain network corresponding to the administrator DID as a recipient, the remittance transaction including a fee statement prepared based on the access rule included in the first URI authentication document. In addition to the above, various embodiments identified through the specification are possible.

Abstract: Disclosed is a cloud DID agent including a memory and at least one processor, in which the at least one processor is configured to receive an upload action request for a file from a mobile agent, generate an encryption key corresponding to the file in response to the upload action request and encrypt the file based on the encryption key, generate a plurality of chunks by dividing the encrypted file into a predetermined size, generate a plurality of data blocks corresponding to each of the plurality of chunks, and distribute and transmit the plurality of data blocks to a plurality of external cloud servers so that the plurality of data blocks are distributed and stored in the plurality of external cloud servers. In addition to this, various embodiments grasped through the specification are possible.

Abstract: Disclosed is a multi-blockchain network comprising an infra relay chain, a plurality of validators determining governance of the multi-blockchain network and a plurality of parachains including a first parachain and a second parachain connected to the infra relay chain, wherein the first parachain is configured to generate a first transaction including a vote for a first blockchain account and having a first fee, wherein the second parachain is configured to generate a second transaction including a vote for a second blockchain account and having a second fee, and wherein the infra relay chain is configured to elect the plurality of validators based on the votes for the first and second blockchain accounts and the first and second fees. In addition to this, various embodiments grasped through the specification are possible.

Abstract: The present disclosure relates to a method for vaccination management including at least: transmitting, by a medical institution device, a vaccination certificate issuance request, an identity certification verifiable credential (VC) for a user, a vaccination agency VC for a medical institution, and a digital signature of the medical institution, to a trusted institution server; verifying, by the trusted institution server, the vaccination agency VC based on a digital signature of a VC issuer included in the vaccination agency VC and the identifier of the trusted institution stored in a public distributed ledger; determining, by the trusted institution server, whether there is an authority for the vaccination certificate issuance request based on the vaccination agency VC and a medical institution database stored in the trusted institution server; and issuing, by the trusted institution server, a vaccination certification VC.

Abstract: A blockchain system is disclosed. A blockchain system according to one embodiment includes a plurality of nodes for communicating with each other through a distribution network and communicating with a blockchain client device outside the blockchain system, wherein each of the plurality of nodes can be configured to process transactions occurring in the blockchain system, collect vote items included in the transactions and including an account address corresponding to any one of the plurality of nodes, and elect, as a block generator, at least one of the plurality of nodes on the basis of the collected vote items. Other various embodiments identified through the specification are possible.

Abstract: A blockchain system is disclosed. A blockchain system according to one embodiment includes a plurality of nodes for communicating with each other through a distribution network and communicating with a blockchain client device outside the blockchain system, wherein each of the plurality of nodes can be configured to process transactions occurring in the blockchain system, collect vote items included in the transactions and including an account address corresponding to any one of the plurality of nodes, and elect, as a block generator, at least one of the plurality of nodes on the basis of the collected vote items. Other various embodiments identified through the specification are possible.