Anonymous reputation construction method

Abstract

The anonymous reputation construction method comprises the following steps: initializing a block chain operation system; the user side generates a private key and a pseudonym; the user side generates a reputation token and a serial number; uploading the block chain; consensus node verification; and updating the reputation. According to the method, the reputation token is invalid after interaction between the user and other entities is completed, the user is required to retrieve the new reputation token from the block chain network, and the new reputation token is updated before being retrieved, so that forced reputation updating is completed. According to the mechanism, timely and correct updating of the reputation of the user is ensured, and the problem that the user selectively updates the reputation in a traditional decentralized reputation system is solved. By hiding the serial number of the reputation token, when the verification server assists in updating the reputation, the subsequent use scene of the reputation token cannot be acquired, so that the privacy protection of the user is enhanced.

Description

Technical Field

[0001] The present invention relates to the field of network security technology, and in particular to an anonymous decentralized reputation building method. Background Art

[0002] The reputation mechanism is a mechanism based on blockchain technology that is used to evaluate and record the reputation and trust of participants in the blockchain network. It is an important social governance tool in the blockchain community, which aims to promote honest behavior of participants, prevent malicious behavior and improve the overall security of the network. Users can choose entities with higher reputation values ​​to interact, thereby ensuring the reliability and security of the network. More and more systems and applications have added reputation mechanisms to solve the trust problem between entities and ensure the security of users and networks.

[0003] In traditional centralized platforms, the centralized server that coordinates the entire communication is too powerful. Once the server is threatened, it may lead to the leakage of user sensitive information. Therefore, the traditional central system structure is fragile. In order to overcome the shortcomings of centralized platforms, decentralized platforms have attracted widespread attention in the industry. Decentralized platforms store reputation-related data on the blockchain, and any user can publicly verify the reputation value of others by accessing the blockchain. However, some decentralized reputation systems have defects in data privacy protection, and cannot hide user identities and cannot ensure that reputations are correctly updated. Tassos Dimitriou proposed a decentralized reputation structure and system that can guarantee user privacy, but cannot ensure that reputations are correctly updated every time. Wu et al. proposed a privacy-focused verification protocol and designed a smart contract-enforced reputation evaluation model, but the cost of using smart contracts is high each time.

[0004] Although the existing decentralized reputation platform can protect user privacy to a certain extent, there are still many shortcomings. Due to the protection of anonymity, the user end can choose a higher reputation rating update, which is undoubtedly unfair to other honest entities, and the reputation update cycle on the blockchain is long and inefficient. Therefore, it is necessary to improve the reputation structure to ensure user privacy while enforcing reputation updates and improve update efficiency. Summary of the invention

[0005] The technical problem to be solved by the present invention is to overcome the shortcomings of the prior art and provide an anonymous reputation building method that enhances user privacy protection, improves system efficiency, and encourages users to behave well.

[0006] The technical solution adopted to solve the above technical problems is: an anonymous reputation building method, comprising the following steps:

[0007] Step 1. Initialize the blockchain operating system

[0008] Input a security parameter l, and output a multiplication cyclic group G1 with a large prime number q as the order. The generator of the multiplication cyclic group G1 is g, and the elements in the multiplication cyclic group G1 are h1, h2, h3, where r1, r2, r3 are random numbers;

[0009] Define a collision-resistant pseudo-random function PRF sk (x), sk is the private key;

[0010] Step 2. The client generates a private key and pseudonym

[0011] The user end selects a random number as the private key sk and uses the private key sk to generate the pseudonym pse;

[0012] Step 3. The user generates a reputation token and serial number

[0013] The user terminal initializes the reputation value v, selects random numbers s and r / , generates a reputation token rep and a serial number sn; the reputation token rep is The sequence number sn is sn:=PRF sk (s);

[0014] Step 4. Upload the blockchain

[0015] The user generates a zero-knowledge proof π mint , proves the correctness of the reputation token and will contain the reputation token rep and the proof π mint The transaction order is uploaded to the blockchain;

[0016] Step 5. Consensus node verification

[0017] The consensus node of the blockchain verifies the proof π in the transaction order mint Is it correct? If it is correct, the reputation token rep is submitted to the Merkle tree. At this point, the user end can interact with other entities;

[0018] Step 6. Reputation Update

[0019] Step 6.1. After interacting with other entities, the user receives the reputation evaluation v of other entities r , disclose a serial number that does not appear in the list of deregistered serial numbers, and the original reputation token rep held by the user becomes invalid;

[0020] Step 6.2. The user reconstructs the reconstructed reputation token rep re , and give the reconstruction proof π re Proof of Reconstruction Reputation Token rep re The reputation value is the same as the original reputation token rep;

[0021] Step 6.3. The user end converts the original reputation token rep and the reconstructed reputation token rep re And reconstruction proof π re Send to the verification server;

[0022] Step 6.4. Verification server verifies reconstruction proof π re If it is invalid, the verification failure is sent to the user; if it is valid, the transaction order on the blockchain is matched according to the original reputation token rep, and the original reputation evaluation v of the user is found. r ;

[0023] Step 6.5. Verify that the server evaluates v based on the original reputation r according to Get a promise CM r , where r″′ and β are random numbers, and the new reputation token rep is obtained new =rep re CM r , and finally generate a new transaction order tx up Upload to blockchain;

[0024] Step 6.6. The client obtains random numbers r″′, β, v from the blockchain r , restore the new reputation token rep new , get the new sequence number sn new , the client can prove that the reputation token is stored in a Merkle tree child node.

[0025] As a preferred technical solution, the pseudonym pse in step 2 is: r is a random number.

[0026] As a preferred technical solution, the proof π described in step 4 mint for:

[0027]

[0028] Where zkSNAPK{·} is an arbitrarily chosen concise non-interactive zero-knowledge proof;

[0029] The transaction order is:

[0030] tx mint :=(pse,rep,v,s,π mint >

[0031] In the formula, tx mint It’s a transaction order.

[0032] As a preferred technical solution, the reputation token rep reconstructed in step 6.2 reFor: rep re =g r″ h1 sk h2 s′ ·h3 v , r″ and s′ are random numbers; the reconstruction proves π re for:

[0033]

[0034] As a preferred technical solution, the new reputation token rep in step 6.6 new for: The new serial number Sn new For: sn new =PRF sk (s′+β), s′ is a random number.

[0035] The beneficial effects of the present invention are as follows:

[0036] The present invention completes the mandatory update of reputation by invalidating the reputation token after the user completes the interaction with other entities and requiring the user to retrieve a new reputation token from the blockchain network. The new reputation token has been updated before retrieval, thereby completing the mandatory update of reputation. This mechanism ensures the timely and correct update of user reputation and solves the problem of user selective reputation update in traditional decentralized reputation systems.

[0037] The present invention hides the serial number of the reputation token so that the verification server cannot obtain the subsequent usage scenario of the reputation token when assisting in updating the reputation, thereby enhancing the privacy protection of the user.

[0038] The present invention assists in updating through the verification server, and only needs to append a single block to the blockchain to end the update cycle, which significantly improves the update efficiency. The existing decentralized reputation platform usually needs to append multiple blocks to the blockchain to end the update cycle when updating the reputation. Therefore, the present invention solves the problem of long update cycle and low efficiency of traditional decentralized reputation platforms.

[0039] The present invention encourages users to maintain honest behavior in a decentralized network, so that entities with higher reputation values ​​in the system are more likely to gain the trust of other entities. This mechanism encourages users to continue to show good behavior to maintain and improve their reputation values. BRIEF DESCRIPTION OF THE DRAWINGS

[0040] Figure 1 It is a structural schematic diagram of the present invention. DETAILED DESCRIPTION

[0041] The present invention will be further described in detail below in conjunction with the accompanying drawings and examples, but the present invention is not limited to the following embodiments.

[0042] exist Figure 1 In this embodiment, an anonymous reputation building method includes the following steps:

[0043] Step 1. Initialize the blockchain operating system

[0044] Input a security parameter l, and output a multiplication cyclic group G1 with a large prime number q as the order. The generator of the multiplication cyclic group G1 is g, and the elements in the multiplication cyclic group G1 are h1, h2, h3, where r1, r2, r3 are random numbers;

[0045] Define a collision-resistant pseudo-random function PRF sk (x), used to generate a serial number, where sk is the private key;

[0046] Step 2. The client generates a private key and pseudonym

[0047] The user end selects a random number as the private key sk and uses the private key sk to generate the pseudonym pse. r is a random number used to protect the user's identity anonymity;

[0048] Step 3. The user generates a reputation token and serial number

[0049] The user initializes the reputation value v, selects random numbers s and r / , and generates a reputation token rep. Serial number sn, Sn: = PRF sk (s);

[0050] Step 4. Upload the blockchain

[0051] The user generates a zero-knowledge proof π mint , prove the correctness of reputation tokens, zkSNAPK{·} is an arbitrarily chosen concise non-interactive zero-knowledge proof that proves π mint Generate transaction order tx mint Upload to blockchain, tx mint :=(pse,rep,v,s,π mint >

[0052] Step 5. Consensus node verification

[0053] Blockchain nodes verify the proof π in the transaction mint Is it correct? If it is correct, the reputation token rep is submitted to the Merkle tree. At this point, the user end can interact with other entities;

[0054] Step 6. Reputation Update

[0055] Step 6.1. After interacting with other entities, the user receives the reputation evaluation v of other entities r , disclose a serial number that does not appear in the list of deregistered serial numbers, and the original reputation token rep held by the user becomes invalid;

[0056] Step 6.2. The user reconstructs the reconstructed reputation token rep re , rep re =g r″ h1 sk h2 s′ h3 v , r″ and s′ are random numbers, and the reconstruction proof π is given re Proof of Reconstruction Reputation Token rep re The reputation value of the original reputation token rep is the same as the reconstruction proof π re for:

[0057]

[0058] Step 6.3. The user end converts the original reputation token rep and the reconstructed reputation token rep re And reconstruction proof π re Send to the verification server;

[0059] Step 6.4. Verification server verifies reconstruction proof π re If it is invalid, the verification failure is sent to the user; if it is valid, the transaction order on the blockchain is matched according to the original reputation token rep, and the original reputation evaluation v of the user is found. r ;

[0060] Step 6.5. Verify that the server evaluates v based on the original reputation r according to Get a promise CM r , where r″′ and β are random numbers, and the new reputation token rep is obtained new =rep re CM r , and finally generate a new transaction order tx up Upload to blockchain;

[0061] Step 6.6. The client obtains random numbers r″′, β, v from the blockchain r , restore the new reputation token rep new , Get the new serial number sn new , sn new =PRF sk(s′+β), the user can prove that the reputation token is stored in the Merkle tree child node.

Claims

1. An anonymous reputation building method, characterized in that: The following steps are involved: Step 1. Initialize the blockchain operating system Input a security parameter l, and output a multiplication cyclic group G1 with a large prime number q as the order. The generator of the multiplication cyclic group G1 is g, and the elements in the multiplication cyclic group G1 are h1, h2, h3, where r1, r2, r3 are random numbers; Define a collision-resistant pseudo-random function PRF sk (x), sk is the private key; Step 2. The user generates a private key and pseudonym The user end selects a random number as the private key sk and uses the private key sk to generate the pseudonym pse; Step 3. The user generates a reputation token and serial number The user terminal initializes the reputation value v, selects random numbers s and r / , generates a reputation token rep and a serial number sn; the reputation token rep is The sequence number sn is sn:=PRF sk (s); Step 4. Upload the blockchain The user generates a zero-knowledge proof π min t , used to prove the correctness of the reputation token and will contain the reputation token rep and the proof π min t The transaction order is uploaded to the blockchain; Step 5. Consensus node verification The consensus node of the blockchain verifies the proof π in the transaction order min t Is it correct? If it is correct, the reputation token rep is submitted to the Merkle tree. At this point, the user end can interact with other entities; Step 6. Reputation Update Step 6.

1. After interacting with other entities, the user receives the reputation evaluation v of other entities r , disclose a serial number that does not appear in the list of deregistered serial numbers, and the original reputation token rep held by the user becomes invalid; Step 6.

2. The user reconstructs the reconstructed reputation token rep re , and give the reconstruction proof π re Proof of Reconstruction Reputation Token rep re The reputation value is the same as the original reputation token rep; Step 6.

3. The user end converts the original reputation token rep and the reconstructed reputation token rep re And reconstruct proof π re Send to the verification server; Step 6.

4. Verification server verifies reconstruction proof π re If it is invalid, the verification failure is sent to the user; if it is valid, the transaction order on the blockchain is matched according to the original reputation token rep, and the original reputation evaluation v of the user is found. r ; Step 6.

5. Verify that the server evaluates v based on the original reputation r according to Get a promise CM r , where r″′ and β are random numbers, and the new reputation token rep is obtained new =rep re CM r , and finally generate a new transaction order tx up Upload to blockchain; Step 6.

6. The client obtains random numbers r″′, β, v from the blockchain r , restore the new reputation token rep new , get the new sequence number sn new , the client can prove that the reputation token is stored in a Merkle tree child node.

2. According to claim 1, a method for building an anonymous reputation, characterized in that: The pseudonym pse in step 2 is: r is a random number.

3. According to claim 2, a method for building an anonymous reputation is characterized in that: Prove π as described in step 4 min t for: Where zkSNAPK{·} is an arbitrarily chosen concise non-interactive zero-knowledge proof; The transaction order is: tx min t :=<pse,rep,v,s,π min t > In the formula, tx min t It’s a transaction order.

4. The anonymous reputation building method according to claim 1, characterized in that: Reconstruct the reputation token rep as described in step 6.2 re For: rep re =g r″ h1 sk h2 s′ ·h3 v , r″ and s′ are random numbers; the reconstruction proves π re for:

5. The anonymous reputation building method according to claim 4, characterized in that: The new reputation token rep described in step 6.6 new for: The new sequence number sn new For: sn new =PRF sk (s′+β), s′ is a random number.

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