A Blockchain-Based Distributed Threshold Digital Identity Authentication Management Method
By constructing a distributed key generation group in the blockchain network, generating a high-order random polynomial function and verifying key sharding, the single point of failure and key management complexity of centralized identity management systems are solved, achieving more secure and reliable digital identity authentication and improving user experience.
Patent Information
- Application Number
- CN202610261916.5
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2026-03-05
- Publication Date
- 2026-05-26
AI Technical Summary
Existing centralized identity management systems suffer from single point of failure risks, complex key management, costly Sybil attack prevention mechanisms, and insufficient privacy protection during identity verification, resulting in poor system security and user experience.
The distributed threshold digital identity authentication method based on blockchain is adopted. A distributed key generation group is formed by selecting a preset number of verification nodes from the blockchain network to generate a high-order random polynomial function. Its constant term is used as a private key fragment. The key fragment is verified by the commitment value. The long-term private key fragment and the joint public key are calculated to generate and verify a partial signature, and finally the identity authentication result is obtained.
It improves the security and reliability of digital identity authentication management, reduces the risk of single points of failure, simplifies key management, enhances user privacy protection, and supports a wider range of application scenarios.
Smart Images
Figure CN122093149A_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of blockchain technology, and in particular to a blockchain-based distributed threshold digital identity authentication management method. Background Technology
[0002] With the rapid development of the digital economy, digital identity authentication has become a critical infrastructure supporting the operation of modern society. Current mainstream identity authentication systems are primarily built on a centralized architecture, a model with fundamental flaws in security, reliability, and user privacy protection. Traditional centralized identity management systems typically use a centralized database to store user identity information and authenticate users through a single authentication center. This architecture design has a significant single point of failure risk; if the authentication server is attacked or malfunctions, the entire system will be paralyzed. Furthermore, centralized systems require users to submit excessive amounts of sensitive personal information, which is centrally stored in the service provider's database, leaving users with no control over their own identity information. To address these challenges, the industry has begun exploring decentralized identity (DID) solutions based on blockchain. Blockchain technology, with its decentralized, immutable, and transparent verifiable characteristics, provides the technological foundation for building a new generation of digital identity management systems. The DID standard specification developed by the W3C defines the basic framework for decentralized identifiers, allowing users to create and manage their digital identities independently.
[0003] However, in terms of key management, most existing DID systems require users to keep their private keys themselves, which poses a significant barrier to entry for ordinary users. In terms of attack resistance, existing solutions mainly rely on economic costs to prevent Sybil attacks, but this mechanism allows attackers to create fake identities in bulk at a low cost when network transaction fees fluctuate. In terms of identity credential management, most systems still rely on a single or a few credential issuing authorities, failing to truly realize the core concept of decentralization. At the same time, the lack of effective privacy protection mechanisms during the identity verification process often requires users to disclose too much unnecessary personal information.
[0004] Therefore, there is an urgent need to build a new generation of decentralized identity management framework to provide a better user experience and broader application scenario support while ensuring system security. Summary of the Invention
[0005] This application provides a blockchain-based distributed threshold digital identity authentication management method to solve the problems of single point of failure and key management complexity in traditional identity management systems. The method includes:
[0006] A predetermined number of verification nodes are selected from the blockchain network to form a distributed key generation group, and a security threshold parameter is set.
[0007] A high-order random polynomial function is generated for each node in the distributed key generation group, and the constant term of the random polynomial function is used as a private key fragment of the node.
[0008] The node's commitment value is determined based on the polynomial coefficients of the random polynomial function, and the node's key fragments are verified based on the commitment value during the key fragmentation exchange phase.
[0009] With all nodes verified, the long-term private key fragment for each node is calculated, and the joint public key is determined based on the initial commitment value of the node.
[0010] The node generates a partial signature of the message by sharding the message with the private key, verifies the generated partial signature, and combines the verified partial signatures into a complete digital signature.
[0011] The identity authentication result is obtained by verifying the complete digital signature using the combined public key.
[0012] Optionally, the commitment value of a node is determined based on the polynomial coefficients of the random polynomial function, satisfying the following formula:
[0013]
[0014] in, For nodes The value of the commitment, and Cyclic group Two independent generators, For polynomial coefficients, It is a blinding factor.
[0015] Optionally, the node's key fragments are verified during the key fragmentation exchange phase based on the commitment value, including:
[0016] Broadcast the node's commitment value to the blockchain network;
[0017] During the key fragmentation exchange phase, the sending node calculates the function value at the index of the receiving node based on its random polynomial function.
[0018] The receiving node receives the generated function value and verifies it using the commitment value broadcast by the sending node.
[0019] Optionally, the receiving node receives the generated function value and verifies it using the commitment value broadcast by the sending node, including:
[0020] Determine whether the function value received by the receiving node and the commitment value broadcast by the sending node satisfy the following formula:
[0021]
[0022] in, For the sending node The index at the receiver node is calculated based on its random polynomial function. The function value at that point, Let be the order of the random polynomial function. For the modulo operation, It is a large prime number;
[0023] If so, the node passes verification;
[0024] If not, the node has failed verification, and a malicious node identification and exclusion protocol will be initiated.
[0025] Optionally, if all nodes pass verification, calculate the long-term private key fragment for each node, satisfying the following formula:
[0026]
[0027] in, For nodes Long-term private key fragmentation, The number of nodes;
[0028] The joint public key is determined based on the initial commitment value of the nodes, satisfying the following formula:
[0029]
[0030] in, For the joint public key, For the first The initial commitment value of each node, For nodes The constant term of the random polynomial function.
[0031] Optionally, the node generates a partial signature for the received message using private key fragmentation, satisfying the following formula:
[0032]
[0033] in, For partial signatures, For the message hash value, For nodes Private key fragmentation;
[0034] The generated partial signature is verified to satisfy the following formula:
[0035]
[0036] in, It is a bilinear pairing function. For nodes Public key fragmentation;
[0037] The verified partial signatures are combined into a complete digital signature, satisfying the following formula:
[0038]
[0039] in, For a complete digital signature, For Lagrange coefficients, The set of nodes participating in the signing. This is the system's master private key;
[0040]
[0041] in, Representing variables To iterate through the collection In addition to the current node All other nodes besides itself.
[0042] This application provides a blockchain-based distributed threshold digital identity authentication management method. This method selects a predetermined number of verification nodes from the blockchain network to form a distributed key generation group and sets a security threshold parameter. For each node in the distributed key generation group, a high-order random polynomial function is generated, and the constant term of the random polynomial function is used as the node's private key fragment. The node's commitment value is determined based on the polynomial coefficients of the random polynomial function, and the node's key fragment is verified based on the commitment value during the key fragment exchange phase. If all nodes pass verification, the long-term private key fragment of each node is calculated, and a joint public key is determined based on the node's initial commitment value. Nodes generate partial signatures for messages using their private key fragments and verify the generated partial signatures, combining the verified partial signatures into a complete digital signature. The complete digital signature is then verified using the joint public key to obtain the identity authentication result, thus improving the security and reliability of digital identity authentication management. Attached Figure Description
[0043] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.
[0044] Figure 1 A flowchart illustrating the blockchain-based distributed threshold digital identity authentication management method provided in this application embodiment.
[0045] The accompanying drawings illustrate specific embodiments of this application, which will be described in more detail below. These drawings and descriptions are not intended to limit the scope of the concept in any way, but rather to illustrate the concept of this application to those skilled in the art through reference to particular embodiments. Detailed Implementation
[0046] To make the objectives, technical solutions, and advantages of this application clearer, the technical solutions of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, not all embodiments. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.
[0047] The terms "first," "second," "third," "fourth," etc. (if present) in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein.
[0048] In this application, the terms "exemplary" or "for example" are used to indicate examples, illustrations, or descriptions. Any embodiment or design described as "exemplary" or "for example" in this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary" or "for example" is intended to present the relevant concepts in a specific manner.
[0049] The technical solution of this application and how the technical solution of this application solves the above-mentioned technical problems are described in detail below with specific embodiments. These specific embodiments can be combined with each other, and the same or similar concepts or processes may not be described again in some embodiments. The embodiments of this application will be described below with reference to the accompanying drawings.
[0050] Figure 1 This is a flowchart illustrating the blockchain-based distributed threshold digital identity authentication management method provided in this application embodiment. Figure 1 As shown in this embodiment, the blockchain-based distributed threshold digital identity authentication management method includes:
[0051] S1: Select a preset number of verification nodes from the blockchain network to form a distributed key generation group, and set security threshold parameters.
[0052] Specifically, n reputable verification nodes are selected from the blockchain network to form a distributed key generation group. These nodes will jointly participate in the key generation process, and the system sets a security threshold parameter t (typically taken as...). This ensures that the system remains secure even if some nodes are compromised.
[0053] S2: Generate a high-order random polynomial function for each node in the distributed key generation group, and use the constant term of the random polynomial function as a fragment of the node's private key.
[0054] Specifically, each participating node Generate a random polynomial function of order t that satisfies the following formula:
[0055]
[0056] in, For nodes Private key fragments, The coefficients are polynomial coefficients, randomly selected from a sufficiently large set of safe prime numbers. For the modulo operation, It is a large prime number.
[0057] Understandably, the order t of the polynomial determines the maximum number of malicious nodes the system can tolerate.
[0058] S3: Determine the node's commitment value based on the polynomial coefficients of the random polynomial function, and verify the node's key fragments during the key fragmentation exchange phase based on the commitment value.
[0059] Specifically, the commitment value of a node is determined based on the polynomial coefficients of the random polynomial function, satisfying the following formula:
[0060]
[0061] in, For nodes The value of the commitment, and Cyclic group Two independent generators, For polynomial coefficients, This is a blinding factor.
[0062] Specifically, the key sharding of a node is verified during the key sharding exchange phase based on the commitment value, including: broadcasting the node's commitment value to the blockchain network; during the key sharding exchange phase, the sending node calculates the function value at the receiving node's index based on its random polynomial function; the receiving node receives the generated function value and verifies it using the commitment value broadcast by the sending node.
[0063] For example, during the key fragmentation exchange phase, each node Need to be for all other nodes Calculate its polynomial at the node index Value at:
[0064]
[0065] in, For the sending node The index at the receiver node is calculated based on its random polynomial function. The function value at that point, This represents indexing the nodes. Substitute node random polynomial function .
[0066] Furthermore, determine whether the function value generated by the receiving node and the commitment value broadcast by the sending node satisfy the following formula:
[0067]
[0068] in, For the sending node The index at the receiver node is calculated based on its random polynomial function. The function value at that point, Let be the order of the random polynomial function. For the modulo operation, It is a large prime number;
[0069] If the function value generated by the receiving node and the commitment value broadcast by the sending node satisfy the above formula, the node passes the verification, and the verification result indicates that the verification was successful.
[0070] If the function value generated by the receiving node does not satisfy the above formula with the commitment value broadcast by the sending node, the node fails the verification. The verification result indicates that the verification failed, which means that a node provided an incorrect key fragment. The system will then initiate a malicious node identification and exclusion protocol.
[0071] This step determines the node's commitment value based on the polynomial coefficients of the random polynomial function, and verifies the node's key fragments during the key fragmentation exchange phase based on the commitment value, ensuring the integrity and correctness of the data.
[0072] S4: With all nodes verified, compute the long-term private key fragment for each node and determine the joint public key based on the node's initial commitment value.
[0073] With all nodes verified, the long-term private key fragments for each node are calculated, satisfying the following formula:
[0074]
[0075] in, For nodes Long-term private key fragmentation, This represents the number of nodes.
[0076] Understandably, the calculated long-term private key fragments will be securely stored by the nodes for subsequent authentication and signing operations.
[0077] The joint public key is determined based on the initial commitment value of the nodes, satisfying the following formula:
[0078]
[0079] in, For the joint public key, For the first The initial commitment value of each node, For nodes The constant term of the random polynomial function.
[0080] Understandably, the above calculation process ensures the authenticity and immutability of the public key.
[0081] Furthermore, the joint public key will be written into the genesis block of the blockchain as the root trust anchor for the entire identity system.
[0082] S5: Nodes generate partial signatures for messages by sharding them with their private keys, verify the generated partial signatures, and combine the verified partial signatures into a complete digital signature.
[0083] Understandably, when the system's master private key is required for signing, a threshold signature scheme is used. This process does not require the complete master private key to be present; instead, it is completed through the collaboration of a sufficient number of nodes. Each participating node uses its own private key fragments to generate partial signatures for the message. These partial signatures are transmitted securely to the aggregation node, where specific mathematical methods are used to combine them into a complete digital signature, ensuring that the final generated signature is completely equivalent to the signature generated directly using the master private key.
[0084] Specifically, the node generates a partial signature for the received message using private key fragmentation, satisfying the following formula:
[0085]
[0086] in, For partial signatures, For the message hash value, For nodes Private key fragmentation;
[0087] The generated partial signature is verified to satisfy the following formula:
[0088]
[0089] in, It is a bilinear pairing function. For nodes The public key fragment passes verification if the above equation holds true;
[0090] The verified partial signatures are combined into a complete digital signature, satisfying the following formula:
[0091]
[0092] in, For a complete digital signature, represent, For Lagrange coefficients, This is the system's master private key;
[0093]
[0094] in, Representing variables To iterate through the collection In addition to the current node All other nodes besides itself.
[0095] In an optional embodiment, after obtaining the public key, a threshold signature protocol is initiated when the system needs to issue a verifiable credential to a user. Multiple verification nodes collaboratively sign the credential content (including user DID, attribute declaration, validity period, etc.) using their respective private key fragments. In this step, the joint public key is the target public key for signing. The ultimate goal of node collaboration is to generate a valid signature that can be verified by the joint public key. This process does not require reconstructing the complete master private key, ensuring key security.
[0096] S6: Verify the complete digital signature using the combined public key to obtain the identity authentication result.
[0097] Specifically, the signature is decrypted using the joint public key, and the signature value is verified to match the hash value of the message to be signed. If the verification is successful, the signature is valid; otherwise, the credential is rejected or an exception is triggered.
[0098] The distributed threshold digital identity authentication management method based on blockchain provided in this application involves selecting a preset number of verification nodes from the blockchain network to form a distributed key generation group and setting a security threshold parameter. For each node in the distributed key generation group, a high-order random polynomial function is generated, and the constant term of the random polynomial function is used as the node's private key fragment. The node's commitment value is determined based on the polynomial coefficients of the random polynomial function, and the node's key fragment is verified based on the commitment value during the key fragment exchange phase. If all nodes pass verification, the long-term private key fragment of each node is calculated, and a joint public key is determined based on the node's initial commitment value. The node generates a partial signature for the message using its private key fragment, verifies the generated partial signature, and combines the verified partial signatures into a complete digital signature. The complete digital signature is then verified using the joint public key to obtain the identity authentication result, thus improving the security and reliability of digital identity authentication management.
[0099] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this application are indicated by the following claims.
[0100] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.
Claims
1. A blockchain-based distributed threshold digital identity authentication management method, characterized in that, The method includes: A predetermined number of verification nodes are selected from the blockchain network to form a distributed key generation group, and a security threshold parameter is set. A high-order random polynomial function is generated for each node in the distributed key generation group, and the constant term of the random polynomial function is used as a private key fragment of the node. The node's commitment value is determined based on the polynomial coefficients of the random polynomial function, and the node's key fragments are verified based on the commitment value during the key fragmentation exchange phase. With all nodes verified, the long-term private key fragment for each node is calculated, and the joint public key is determined based on the initial commitment value of the node. The node generates a partial signature of the message by sharding the message with the private key, verifies the generated partial signature, and combines the verified partial signatures into a complete digital signature. The identity authentication result is obtained by verifying the complete digital signature using the combined public key.
2. The method according to claim 1, characterized in that, The commitment value of a node is determined based on the polynomial coefficients of the random polynomial function, satisfying the following formula: ； in, For nodes The value of the commitment, and Cyclic group Two independent generators, For polynomial coefficients, It is a blinding factor.
3. The method according to claim 2, characterized in that, The node's key fragments are verified during the key fragmentation exchange phase based on the commitment value, including: Broadcast the node's commitment value to the blockchain network; During the key fragmentation exchange phase, the sending node calculates the function value at the index of the receiving node based on its random polynomial function. The receiving node receives the generated function value and verifies it using the commitment value broadcast by the sending node.
4. The method according to claim 3, characterized in that, The receiving node receives the generated function value and verifies it using the commitment value broadcast by the sending node, including: Determine whether the function value received by the receiving node and the commitment value broadcast by the sending node satisfy the following formula: ； in, For the sending node The index at the receiver node is calculated based on its random polynomial function. The function value at that point, Let be the order of the random polynomial function. For the modulo operation, It is a large prime number; If so, the node passes verification; If not, the node has failed verification, and a malicious node identification and exclusion protocol will be initiated.
5. The method according to claim 4, characterized in that, With all nodes verified, the long-term private key fragments for each node are calculated, satisfying the following formula: ； in, For nodes Long-term private key fragmentation, The number of nodes; The joint public key is determined based on the initial commitment value of the nodes, satisfying the following formula: ； in, For the joint public key, For the first The initial commitment value of each node, For nodes The constant term of the random polynomial function.
6. The method according to claim 5, characterized in that, The node generates a partial signature for the received message by sharding the private key, satisfying the following formula: ； in, For partial signatures, For the message hash value, For nodes Private key fragmentation; The generated partial signature is verified to satisfy the following formula: ； in, It is a bilinear pairing function. For nodes Public key fragmentation; The verified partial signatures are combined into a complete digital signature, satisfying the following formula: ； in, For a complete digital signature, For Lagrange coefficients, The set of nodes participating in the signing. This is the system's master private key; ； in, Representing variables To iterate through the collection In addition to the current node All other nodes besides itself.