Public random number generation method and device based on blockchain

A public random number generation device based on a blockchain, comprising the blockchain and a hardware processor, wherein the blockchain ensures that information published thereon is tamper-proof, and the hardware processor is configured to:

• select a node group G, wherein the node group G contains N trusted nodes;
• determine a first time point tm and a second time point tn, wherein the first time point tm is earlier than the second time point tn, the first time point tm is a generation time point of an m-th block, the second time point tn is a generation time point of an n-th block, and the m-th block is fixed and cannot be tampered at the second time point tn,
• at the first time point tm, enable each of the N trusted nodes to separately generate a sub-random number rj, wherein j=1, 2, . . . , N, perform delayed encryption on the sub-random number rj, and place delayed encryption results in the m-th block, wherein the sub-random number rj is a component forming a random number X, and the delayed encryption determines that the encrypted sub-random numbers rj can only be obtained by means of a decryption operation after delay for a period of time;
• and
• at the second time point tn, decrypt the delayed encryption results to obtain decrypted data of all the delayed encryption results, the decrypted data being for all of the sub-random number rj, and perform an operation solvable in polynomial time on all of the sub-random number rj to obtain the random number X, wherein the random number X is a final available public random number.

A non-transitory machine-readable storage medium having stored a computer program thereon, wherein the computer program, when executed by a processor, implements the following steps:

• a selection step of selecting a node group G, wherein the node group G contains N trusted nodes:
• a determination step of determining a first time point tm and a second time point tn, wherein the first time point tm is earlier than the second time point tn, the first time point tm is a generation time point of an m-th block, the second time point tn is a generation time point of an n-th block, and the m-th block is fixed and cannot be tampered at the second time point tn;
• a generation step of at the first time point tm, enabling each of the N trusted nodes to separately generate a sub-random number rj, wherein j=1, 2, . . . N, performing delayed encryption on the sub-random number rj, and placing delayed encryption results in the m-th block, wherein the sub-random number rj is a component forming a random number X, and the delayed encryption determines that the encrypted sub-random numbers rj can only be obtained by means of a decryption operation after delay for a period of time;
• and
• a decryption step of at the second time point tn, decrypting the delayed encryption results to obtain decrypted data of all the delayed encryption results, the decrypted data being for all the sub-random number rj, and performing an operation solvable in polynomial time on all of the sub-random number rj to obtain the random number X, wherein the random number X is a final available public random number.