# US 2020/0401577 A1 · Block Verification Device, Block Verification Method, and Program > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2020/0401577 A1 - Document ID: US20200401577A1 - Status: Published application - Kind: A1 - Application number: 16/957,802 - Filed: 2019-01-18 - Published: 2020-12-24 - Earliest claimed: 2018-01-19 - Assignees: Nippon Telegraph and Telephone Corporation - Applicants: Nippon Telegraph and Telephone Corporation - Inventors: Shigenori Ohashi; Hiroki Watanabe; Shigeru Fujimura; Atsushi Nakadaira; Tatsuro Ishida - Web page: https://patentgrep.com/patent/US20200401577A1 ## CPC - G06F 16/2379: {Updates performed during online database operations; commit processing} - H04L 9/3239: {involving non-keyed hash functions, e.g. modification detection codes [MDCs], MD5, SHA or RIPEMD} - G06F 21/64: Protecting data integrity, e.g. using checksums, certificates or signatures - H04L 9/0637: {Modes of operation, e.g. cipher block chaining [CBC], electronic codebook [ECB] or Galois/counter mode [GCM]} - H04L 63/12: {Applying verification of the received information (cryptographic mechanisms or cryptographic arrangements for data integrity or data verification H04L9/32)} - H04L 9/50: {using hash chains, e.g. blockchains or hash trees} - H04L 2209/56: Financial cryptography, e.g. electronic payment or e-cash - G06F: ELECTRIC DIGITAL DATA PROCESSING (computer systems based on specific computational models G06N) - H04L: TRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION (arrangements common to telegraphic and telephonic communication H04M) ## Abstract A consensus is formed for a private database shared within a group. A block verification device includes: a private database shared within a group; a communication unit receiving a list of transactions from an overall leader device; a transaction processing unit executing the transactions identified based on the list and outputting the execution results; and a block processing unit generating a proposal including a list, a digest of the private database after execution of the transactions, and a private dataset included in the transactions. The communication unit transmits the proposal to another block verification device belonging to the same group, and transmits the list, the digest of the private database, and the digest of the private dataset to all the other block verification devices when it is determined that a consensus for the proposal is formed. ## Claims ### Claim 1 A block verification device in a block verification system that includes a plurality of groups each including a plurality of block verification devices, the block verification device representing the block verification devices included in each group, comprising: a private database that is shared within the group; a communication unit that receives a first transaction list from an overall leader device, which is a block verification device representing all the plurality of the block verification devices; a transaction processing unit that executes transactions identified based on the first transaction list; and a block processing unit that generates a proposal including a second transaction list according to the execution of the transactions, a digest of the private database after the execution of the transactions, and a private dataset as a collection of pieces of private data that are included in the transactions and are shared within the group, wherein the communication unit transmits the proposal to the other block verification devices belonging to the same group, and transmits the second transaction list, the digest of the private database, and a digest of the private dataset to all the other block verification devices when it is determined that the block processing unit forms a consensus for the proposal. ### Claim 2 A block verification device in a block verification system that includes a plurality of groups each including a plurality of block verification devices, the block verification device representing all the block verification devices, comprising: a private database that is shared within the group; a shared database that is shared by all the block verification devices; a communication unit that transmits a first transaction list to each group leader block verification device representing the block verification devices within the group and receives a second transaction list generated according to execution of transactions identified based on the first transaction list, a digest of the private database after the execution of the transactions, and a digest of a private dataset as a collection of pieces of private data that are included in the transactions and are shared within the group when the group leader block verification device forms a consensus for a proposal including the second transaction list, the digest of the private database, and the private dataset; a transaction processing unit that executes transactions corresponding to the second transaction list received from each group leader block verification device and obtains a state of the shared database updated based on the execution results; and a block processing unit that forms a consensus for a block including a list of transactions executed by the transaction processing unit, the state of the shared database, the digest of the private database, and the digest of the private dataset, by transmitting the block to another block verification device. ### Claim 3 A block verification method that is executed by a block verification device in a block verification system that includes a plurality of groups each including a plurality of block verification devices, the block verification device representing the block verification devices included in each group, and the block verification device including a private database that is shared within the group, comprising: receiving a first transaction list from an overall leader device, which is a block verification device representing all the plurality of the block verification devices; executing transactions identified based on the first transaction list; generating a proposal including a second transaction list according to the execution of the transactions, a digest of the private database, and a private dataset as a collection of pieces of private data that are included in the transactions and are shared within the group; transmitting the proposal to the other block verification devices belonging to the same group; and when a consensus for the proposal is formed, transmitting the second transaction list as well as the digest of the private data and the digest of the private dataset based on the execution of the transactions to all the other block verification devices. ### Claim 4 A block verification method that is executed by a block verification device in a block verification system that includes a plurality of groups each including a plurality of block verification devices, the block verification device representing all the block verification devices, and the block verification device including a private database that is shared within the group and a shared database that is shared by all the block verification devices, comprising: transmitting a first transaction list to each group leader block verification device representing the block verification devices within the group; receiving a second transaction list generated according to the execution of transactions identified based on the first transaction list, a digest of the private database after the execution of the transactions, and a digest of a private dataset as a collection of pieces of private data that are included in the transactions and are shared within the group when the group leader block verification device forms a consensus for a proposal including the second transaction list, the digest of the private database, and the private dataset; executing transactions corresponding to the second transaction list received from each group leader block verification device and obtaining a state of the shared database updated based on the execution results; and forming a consensus for a block including a list of the executed transactions, the state of the shared database, the digest of the private database, and a digest of the private dataset, by transmitting the block to another block verification device. ### Claim 5 (depends on 1) A computer readable storage medium storing a program that causes a computer to function as the block verification device according to claim 1. ### Claim 6 (depends on 2) A computer readable storage medium storing a program that causes a computer to function as the block verification device according to claim 2.