Abstract:
A decentralized group signature method for an issuer-anonymized credential system includes (a) an initial system setup operation of defining elements of a group signature method and information that is generated and shared by each group member, (b) an initial group member setup operation, (c) a group member participation operation of adding a new group member to a group, (d) a group signature operation of putting a group signature on a specific message, (e) an operation of verifying the group signature, (f) an operation of removing anonymity from a group signature for a specific group member with agreement of group members, and (g) an operation of revoking a specific group member with agreement of the group members. Exclusive authority of a group manager is distributed to the group members.
Abstract:
Provided is a method of proving ownership and an ownership transfer history using a decentralized identifier (DID). The method includes identifying, by a verifier terminal, a product through a DID and identifying an initial producer of the product through the DID, generating, by the verifier terminal, a proof-of-ownership verifiable credential (VC) of the product, which includes metadata including information on the VC, security information (claims) including information on a belonging, and issuing organization electronic signature information (proof) including a digital signature method and a signature value for content certification of the VC, and providing, by the verifier terminal, the generated proof-of-ownership VC of the product to the producer of the product and storing a DID document of the produced product in a decentralized external storage in a decentralized manner.
Abstract:
Disclosed herein are a method and an apparatus for controlling an interactive lecture service capable of performing questions and answers during a lecture without using a media mixer. A method for providing a media stream switching based interactive lecture service, includes: receiving a right to speak request from at least one student terminal by a lecturer terminal; assigning the right to speak to a specific student terminal in response to the right to speak request and receiving at least one of the question video and voice of the specific student terminal, by the lecturer terminal; and transmitting at least one of the receiving question video and voice of the specific student terminal to a terminal included in a lecture session by the lecturer terminal.