A contact identification information multi-terminal synchronization method, device and system

Abstract

The application discloses a kind of contact identification information multi-terminal synchronization method, device and system, first terminal calls the trusted credential issuing service of communication platform and obtains the verifiable credential VC containing issuer signature and identity attribute declaration, and based on the disclosure strategy configured for second terminal, VC is executed selective disclosure processing, constructs the disclosure presentation credential containing only authorized attribute subset, and embeds the zero-knowledge range proof for the real-name authentication state has been established;The disclosure presentation credential is transmitted to server in uplink;Server verifies the validity of credential signature and unrevoked state, establishes and persistently stores associated mapping data items, and issues the disclosure presentation credential to second terminal in downlink.This application realizes the identity authenticity guarantee and privacy protection of cryptography level by verifiable credential and zero-knowledge proof, and guarantees the consistency and reliability of multi-terminal contact identification information by CRDT multi-terminal incremental synchronization mechanism, while giving consideration to information maintenance efficiency.

Description

Technical Field

[0001] This invention relates to the fields of Internet communication technology and information security technology, specifically to a method, apparatus and system for synchronizing contact identification information across multiple terminals based on a conflict-free copy data type. It is applicable to communication systems built on a distributed client-server architecture, such as instant messaging and social networks. In particular, it relates to achieving targeted synchronization and reliable persistence of contact identification information among specific recipients while ensuring the authenticity of the information subject's identity and the controllability of privacy. Background Technology

[0002] With the rapid development of mobile internet technology, instant messaging and social networking applications have become the basic information infrastructure for daily communication among internet users. In the distributed communication system built by these applications, each registered user corresponds to a uniquely assigned account identifier in the system. Users establish relationships through a contact relationship graph and interact with each other through multimodal data such as text, voice, and video based on these relationships.

[0003] In practice, individual users often maintain a large collection of contacts. To quickly and accurately match online accounts with real identities in subsequent communication sessions, users typically need to maintain identification information (such as real name, organization, job title, and other descriptive attributes) for each contact in the client. This identification information is presented to the user in the contact information display area of ​​the client and is a crucial data foundation for users to identify contact identities and manage contact relationships.

[0004] However, the existing contact identification information maintenance mechanism has the following drawbacks: (1) High maintenance cost and low efficiency. Contact identification information usually relies on the recipient user to manually enter it item by item in the client. The operation path is long and the process is cumbersome. In scenarios with a large number of contacts or batch addition, the time cost and operation burden increase significantly.

[0005] (2) Information asymmetry and lack of authenticity. Recipients often cannot accurately know the true identity attributes of the contact person, especially for newly established contacts, and cannot complete the structured maintenance of identification information; in addition, the identification information is filled in unilaterally by the recipient, and the information subject cannot perceive whether the identification information is accurate, and the authenticity of the data lacks a reliable verification mechanism.

[0006] (3) Lack of privacy protection mechanism. In traditional solutions, if an information subject needs to disclose real identity information to a specific contact, under current technology there are usually only two ways: modifying the public nickname or sending a message point-to-point. The former exposes the real identity information to all associated and unassociated users at the same time, while the latter cannot guarantee that the recipient will write the information in a structured way into the contact identifier field. Neither can effectively control the privacy exposure while meeting the identity display requirements.

[0007] (4) Lack of fine-grained disclosure control capabilities. Existing technologies lack a hierarchical control mechanism for different recipients and different disclosure scopes, and cannot meet the differentiated disclosure needs for different recipient attributes, such as "disclosing the name and unit to colleagues, and disclosing only the name to unfamiliar contacts".

[0008] (5) Lack of revocation and lifecycle management mechanisms. After an information subject completes the disclosure of identity information, there is a lack of means to actively revoke the disclosed information. The disclosed information is permanently retained by the recipient and cannot respond to scenarios such as changes in the information subject's disclosure intentions or the failure of the disclosure strategy.

[0009] (6) Insufficient data consistency across multiple terminals. When the receiving user uses the same account on multiple terminal devices, the set of contact identity information maintained locally on each terminal lacks an effective cross-terminal synchronization and conflict resolution mechanism, making it difficult to avoid information loss in scenarios such as device switching and reset.

[0010] Furthermore, several alternative solutions for identity information transmission exist in existing technologies, such as: identity token schemes based on OAuth2.0 or OpenID Connect, which focus on identity authentication rather than attribute disclosure; access control schemes based on Attribute-Based Encryption (ABE), which focus on data encryption rather than the targeted distribution and display of identity information; and traditional digital signature credential schemes, which do not support selective disclosure and require the recipient to obtain the complete credential. None of these solutions can simultaneously meet the practical requirements for contact identification information disclosure in terms of ensuring identity authenticity, privacy control, and consistency across multiple platforms.

[0011] In summary, existing technologies lack a contact identification information disclosure mechanism that integrates verifiable credentials, selective disclosure, and lifecycle management. They cannot simultaneously ensure the authenticity of credential issuance, provide fine-grained selective disclosure for different recipients, enable proactive revocation and invalidation propagation, and achieve incremental consistency synchronization across multiple terminals. Summary of the Invention

[0012] To address the comprehensive shortcomings of existing contact identification information disclosure mechanisms in terms of identity authenticity assurance, fine-grained privacy control, revocation lifecycle management, and multi-terminal data consistency, this invention provides a method, apparatus, and system for multi-terminal synchronization of contact identification information based on conflict-free replicated data type. It integrates Verifiable Credential (VC) technology, Zero-Knowledge Proof (ZKP) technology, attribute-based access control technology, and conflict-free replicated data type (CRDT) technology to achieve the following technical effects: the information subject's terminal proactively initiates selective identity information disclosure based on a trusted credential issuance service. The credential contains a cryptographically signed identity attribute statement. The information subject can implement fine-grained differentiated disclosure control for different recipients through a disclosure strategy engine. The server establishes persistent association mapping data items based on credential verification and ensures the reliability and consistency of information through a revocation propagation mechanism and a multi-terminal CRDT synchronization mechanism. This significantly reduces the cost of maintaining identification information while achieving a balance between identity authenticity and privacy control.

[0013] To achieve the above objectives, the present invention adopts the following technical solution:

[0014] The second terminal receives and parses the disclosure presentation certificate for the first identity subject. The disclosure presentation certificate is constructed by the first terminal based on the verifiable certificate VC and the disclosure strategy configured for the second terminal. The disclosure presentation certificate carries identity identification information containing only a subset of authorized attributes and zero-knowledge scope proof for the real-name authentication status. The second terminal maintains a set of local contact identity information using a conflict-free copy data type (CRDT) structure, and writes a subset of the authorization attributes from the disclosure presentation credential into the CRDT structure; In response to the local update of the second terminal, the second terminal transmits an incremental synchronization message to the server. The server acts as a synchronization hub, broadcasting the incremental synchronization message to other associated terminals of the second terminal; Each associated terminal receives and independently merges the incremental synchronization messages locally based on the CRDT structure, and converges to a consistent state using a preset conflict resolution strategy.

[0015] In one optional implementation, the disclosure strategy is encoded using an attribute-based access strategy expression, which is encoded based on one or more of the following attributes: the type of association between the recipient and the first identity entity, the duration of the association establishment, the group to which the recipient belongs, and the recipient's authentication level on the communication platform. This enables differentiated disclosure control tailored to different recipient attributes.

[0016] In one optional implementation, the CRDT structure is a CRDT Map structure, where each contact identification information entry in the set is represented by a CRDT node; the preset conflict resolution strategy is a Last-Write-Wins strategy based on version vectors or timestamps, or an unordered set OR-Set strategy based on unique identifiers, so that each associated terminal can converge to a consistent state without the intervention of a central coordinating node in conflict resolution.

[0017] In one optional implementation, each disclosure operation generates a disclosure ticket carrying a unique serial number and validity period; if the first identity subject performs an active revocation operation or the disclosure policy expires, the server generates a revocation event and broadcasts the revocation event to each terminal that has received the disclosure presentation certificate, and each terminal marks the corresponding contact identification information as invalid and stops rendering.

[0018] Receive an association mapping request transmitted uplink from the first terminal, the association mapping request carrying the terminal identifier of the second terminal and the disclosure presentation certificate constructed by the first identity subject; Parse and verify the validity of the cryptographic signature of the disclosure presentation certificate and its unrevoked status. After successful verification, establish and persistently store the association mapping data item between the terminal identifier of the second terminal and the disclosure presentation certificate. The disclosure presentation certificate is sent down to the second terminal, which maintains the contact identity information set in a CRDT structure. As a synchronization hub, it receives incremental synchronization messages from the second terminal and broadcasts them to other associated terminals, coordinating multi-terminal CRDT data synchronization. In response to a revocation event, the revocation event is broadcast to each terminal that has received the disclosure presentation certificate; After the second terminal resets or deletes the association with the first identity subject, the associated storage disclosure presentation certificate is returned in response to the retrieval request.

[0019] The first terminal constructs a disclosure presentation certificate based on the verifiable credential (VC) and disclosure strategy, and transmits the disclosure presentation certificate directly to the second terminal via a secure communication connection established with the second terminal. The second terminal maintains a set of contact identification information using a CRDT structure and writes it into a subset of authorization attributes; The second terminal and each associated terminal incrementally synchronize contact identity information in the network through the secure communication connection based on the CRDT structure, and converge to a consistent state based on a preset conflict resolution strategy.

[0020] The interface rendering module 11 is used to render the first identity configuration interface, which is used to provide an entry point for disclosing the identity information of the first identity subject to the contact information display area corresponding to the second terminal. The credential acquisition module 12 is used to call the trusted credential issuance service of the communication platform to obtain the verifiable credential VC under the name of the first identity subject. The credential construction module 13 is used to perform selective disclosure processing on the VC based on the disclosure policy configured for the second terminal, and construct a disclosure presentation credential that contains only a subset of authorized attributes, wherein the disclosure presentation credential also includes a zero-knowledge scope proof for the real-name authentication status. The uplink module 14 is requested to transmit an association mapping request carrying the terminal identifier of the second terminal and the disclosure presentation certificate to the server. Downlink receiving module 15 is used to receive and parse the disclosure presentation certificate issued by the server; The information rendering module 16 is used to render and present the subset of authorized attributes parsed by the downlink receiving module 15 in the contact information display area; The revocation management module 17 is used to monitor information disclosure revocation events and mark the corresponding contact identification information as invalid. The multi-terminal synchronization module 18 is used to maintain a set of contact identification information in a CRDT structure and perform incremental synchronization with other associated terminals.

[0021] The request receiving module 21 is used to receive the association mapping request transmitted uplink from the first terminal, wherein the association mapping request carries the terminal identifier of the second terminal and the disclosure presentation certificate constructed by the first identity subject. The credential verification module 22 is used to parse the association mapping request and verify the validity of the cryptographic signature of the disclosure presentation credential and the credential's unrevoked status; The mapping storage module 23 is used to associate the terminal identifier of the second terminal with the disclosure presentation certificate and store it in the identifier mapping database configured for the second terminal after the verification is passed; The revocation management module 24 is used to broadcast the revocation event to each terminal that has received the disclosure presentation certificate in response to the revocation event; The retrieval and retrospection module 25 is used to return the associated disclosure presentation credentials stored in the relevant storage to the terminal that initiated the retrieval request in response to the retrieval request after the second terminal resets or deletes the association relationship with the first identity subject. The synchronization hub module 26 is used as a synchronization hub to receive incremental synchronization messages from each terminal and broadcast them to other associated terminals, coordinating multi-terminal CRDT data synchronization.

[0022] The first terminal is used to call the trusted credential issuance service of the communication platform to obtain a verifiable credential (VC), construct a disclosure presentation credential based on the disclosure strategy, and transmit an association mapping request to the server. The server is used to verify the disclosure presentation credential, establish and persistently store associated mapping data items, send the disclosure presentation credential downlink, and act as a synchronization hub to coordinate multi-terminal CRDT data synchronization and revocation propagation. The second terminal and the plurality of associated terminals are used to receive and parse the disclosure presentation credentials, maintain a set of contact identity information in a CRDT structure, and independently merge and converge to a consistent state locally based on incremental synchronization messages. Compared with the prior art, the present invention has the following beneficial effects:

[0023] (1) Multi-terminal incremental consistency synchronization: The incremental synchronization mechanism based on the CRDT structure enables each associated terminal to maintain a set of contact identity information through the CRDT node. The server acts as the synchronization hub and broadcasts incremental synchronization messages. Each terminal independently merges incremental updates locally based on the CRDT structure and resolves concurrent conflicts using the Last-Write-Wins or OR-Set strategy. No central coordination node is required. In scenarios such as device replacement and reset, lossless reconstruction and eventual consistency convergence of contact identity information are achieved. This technical solution has not been disclosed in the existing technology search and has significant inventiveness. (2) Cryptographic-level authenticity guarantee: The disclosure certificate contains the cryptographic signature of the trusted certificate issuer. The server can verify the authenticity of the certificate content by verifying the validity of the signature. There is no need to rely on the transmission and comparison of plaintext real-name authentication data. The authenticity and non-forgeability of the identity information are guaranteed from the cryptographic level. (3) Fine-grained selective disclosure: The information subject configures different attribute disclosure ranges for different recipients through the disclosure strategy engine. The disclosure presentation certificate only contains a subset of authorized attributes and does not expose unauthorized attributes, thus achieving fine-grained privacy control while meeting the identity display requirements. (4) Zero-knowledge proof enhances privacy: Zero-knowledge proof is embedded in the credential for the real-name authentication status. The recipient or the server can verify the real-name authentication status of the information subject without obtaining the specific real-name authentication information, effectively preventing the leakage of the original real-name authentication data. (5) Complete revocation and lifecycle management: Each disclosure generates a disclosure note with a unique serial number and validity period, supporting the information subject's active revocation and automatic expiration of the policy. The revocation event is transmitted to each receiving terminal in real time through the server broadcast mechanism, which solves the technical defect that information cannot be revoked after disclosure in the existing technology. (6) Significantly reduce maintenance costs: The recipient can obtain structured and standardized identity information in the contact information display area without performing any manual input operations, which significantly reduces manual maintenance costs in scenarios with a large number of contacts. Attached Figure Description

[0024] Figure 1 This is a flowchart illustrating a method for synchronizing contact identification information across multiple terminals based on a conflict-free copy data type, as provided in an embodiment of the present invention. Figure 2 A schematic diagram of the structure of a multi-terminal synchronization device for contact identification information (terminal side) provided in an embodiment of the present invention; Figure 3 A schematic diagram of another multi-terminal synchronization device for contact identification information (server side) provided in an embodiment of the present invention; Figure 4 This is a schematic diagram of the structure of a multi-terminal synchronization system for contact identification information provided in an embodiment of the present invention. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of the present invention. Example

[0026] Please see Figure 1 , Figure 1 This is a flowchart illustrating a multi-terminal synchronization method for contact identification information provided in an embodiment of the present invention. The core innovation of this embodiment lies in the following: after the information subject terminal selectively discloses its identification information based on verifiable credentials, the receiver maintains a set of contact identification information using a conflict-free copy data type (CRDT) structure, and the server acts as the synchronization hub to achieve incremental consistency synchronization among multiple terminals. The method described in this embodiment can be applied to a distributed communication system composed of user terminal devices such as mobile phones, tablets, and smart wearable devices, and a communication platform server node. Specifically, it includes the following steps: S101. The first terminal calls the trusted credential issuance service of the communication platform to obtain the verifiable credential VC under the name of the first identity subject, and performs selective disclosure processing on the VC based on the disclosure policy configured for the second terminal to construct a disclosure presentation credential containing only a subset of authorized attributes, wherein the disclosure presentation credential also includes a zero-knowledge scope proof for the real-name authentication status; the first terminal transmits an association mapping request carrying the terminal identifier of the second terminal and the disclosure presentation credential to the server.

[0027] S102. The server parses the association mapping request, verifies the validity of the cryptographic signature of the disclosure presentation credential and the credential's unrevoked status. After successful verification, it establishes and persistently stores the association mapping data item between the terminal identifier of the second terminal and the disclosure presentation credential, and then sends the disclosure presentation credential downlink to the second terminal.

[0028] S103. The second terminal receives and parses the disclosure presentation certificate, extracts the authorization attribute subset from the certificate, writes the authorization attribute subset into the local contact identity information set using a CRDT Map structure, and renders the authorization attribute subset in the contact information display area of ​​the second terminal corresponding to the first identity subject.

[0029] S104. In response to the local write or update operation of the second terminal, the second terminal generates an incremental synchronization message and transmits it to the server. The incremental synchronization message includes the CRDT node that has changed in the CRDT structure and the corresponding version vector.

[0030] S105. The server acts as a synchronization hub, maintains a global state vector of the contact identity information set using the account identifier of the second terminal as an index, and broadcasts the incremental synchronization message to other associated terminals of the second terminal.

[0031] S106. Each associated terminal receives the incremental synchronization message and independently merges the incremental updates locally based on the CRDT structure. When concurrent updates occur, conflicts are resolved using the Last-Write-Wins strategy or the OR-Set strategy based on a unique identifier. No central coordination node is required, and each terminal converges to a consistent state.

[0032] S107. The second terminal continuously monitors information disclosure revocation events. If it detects that the first identity subject performs an active revocation operation, the disclosure strategy expires, or the underlying VC is revoked, the server generates a revocation event and broadcasts the revocation event to each terminal that has received the disclosure presentation certificate. Each terminal marks the corresponding contact identification information as invalid and stops rendering.

[0033] S108. If the second terminal resets or deletes its association with the first identity subject, when the server receives a retrieval request based on the first identity subject, it performs an association query in the identity mapping database using the terminal identifier of the second terminal as the retrieval condition. If the account corresponding to the first identity subject is found, the associated disclosure presentation certificate is returned back to the terminal that initiated the retrieval request, thereby realizing the lossless reconstruction of identity information.

[0034] Optionally, the construction of the disclosure presentation credential in step S101 can be implemented as follows: the data format of the verifiable credential (VC) refers to the W3C Verifiable Credentials Data Model v1.1 standard, and the credential body data structure includes at least a unique credential identifier, a credential issuer identifier, a credential issuance time and expiration time, a credential holder identifier, a set of holder identity attribute statements, and the digital signature of the credential issuer; the disclosure strategy is encoded with an attribute-based access strategy expression (such as a CP-ABE access tree structure), and a subset of authorized attributes is selected based on the recipient's association type, establishment duration, group affiliation, and authentication level; the zero-knowledge scope proof can use the Sigma protocol or Bulletproofs scope proof, and the disclosure presentation credential is constructed with reference to the W3C Decentralized Identifiers (DIDs) v1.0 and Verifiable Presentations standards. Example

[0035] Please see Figure 2 , Figure 2 This is a schematic diagram of a multi-terminal synchronization device (terminal side) for contact identification information provided in an embodiment of the present invention. The device described in this embodiment can be installed in user terminal devices such as mobile phones, tablets, and smart wearable devices. Specifically, the device includes: The interface rendering module 11 is used to render the first identity configuration interface, which is used to provide an entry point for disclosing the identity information of the first identity subject to the contact information display area corresponding to the second terminal. The credential acquisition module 12 is used to call the trusted credential issuance service of the communication platform to obtain the verifiable credential VC under the name of the first identity subject. The credential construction module 13 is used to perform selective disclosure processing on the VC based on the disclosure policy configured for the second terminal, and construct a disclosure presentation credential that contains only a subset of authorized attributes, wherein the disclosure presentation credential also includes a zero-knowledge scope proof for the real-name authentication status. The uplink module 14 is requested to transmit an association mapping request carrying the terminal identifier of the second terminal and the disclosure presentation certificate to the server. Downlink receiving module 15 is used to receive and parse the disclosure presentation certificate issued by the server; The information rendering module 16 is used to render and present the subset of authorized attributes parsed by the downlink receiving module 15 in the contact information display area; The revocation management module 17 is used to monitor information disclosure revocation events and mark the corresponding contact identification information as invalid. The multi-terminal synchronization module 18 is used to maintain a set of contact identification information in a CRDT structure and perform incremental synchronization with other associated terminals.

[0036] Among them, the interface rendering module 11, the voucher acquisition module 12, the voucher construction module 13, and the request uplink module 14 constitute the uplink (voucher construction and sending channel); the downlink receiving module 15 and the information rendering module 16 constitute the downlink (voucher receiving and rendering channel); the cancellation management module 17 and the multi-terminal synchronization module 18 are local management modules that operate independently. Example

[0037] Please see Figure 3 , Figure 3 This is a schematic diagram of another multi-terminal synchronization device (server side) for contact identification information provided in an embodiment of the present invention. The device described in this embodiment can be installed in a server-side node such as an application server of a communication platform. Specifically, the device includes: The request receiving module 21 is used to receive the association mapping request transmitted uplink from the first terminal, wherein the association mapping request carries the terminal identifier of the second terminal and the disclosure presentation certificate constructed by the first identity subject. The credential verification module 22 is used to parse the association mapping request and verify the validity of the cryptographic signature of the disclosure presentation credential and the credential's unrevoked status; The mapping storage module 23 is used to associate the terminal identifier of the second terminal with the disclosure presentation credential and store it in the identifier mapping database configured for the second terminal (persistent writing) after the verification is successful. The revocation management module 24 is used to broadcast the revocation event to each terminal that has received the disclosure presentation certificate in response to the revocation event; The retrieval and backtracking module 25 is used to retrieve and read the associated disclosure presentation certificate from the identifier mapping database in response to the retrieval request after the second terminal resets or deletes the association relationship with the first identity subject, and backtrack the certificate to the terminal that initiated the retrieval request. The synchronization hub module 26 is used as a synchronization hub to receive incremental synchronization messages from each terminal and broadcast them to other associated terminals, coordinating multi-terminal CRDT data synchronization. Example

[0038] Please see Figure 4 , Figure 4 This is a schematic diagram of a multi-terminal synchronization system for contact identification information provided in an embodiment of the present invention. The system includes a first terminal 1, a credential issuance service 2, a server 3, and a second terminal 4 (and multiple associated terminals of the second terminal), wherein: The first terminal 1 is used to render the first identity configuration interface, call the credential issuance service 2 of the communication platform to obtain the verifiable credential VC, construct the disclosure presentation credential based on the disclosure strategy, and transmit the association mapping request to the server 3. The credential issuance service 2 is used to issue a verifiable credential VC containing the issuer's signature and the first identity subject's identity attribute declaration based on the real-name authentication record of the first terminal 1. The server 3 is used to verify the validity of the cryptographic signature of the disclosure presentation certificate and its unrevoked status, establish and persistently store the associated mapping data item, send the disclosure presentation certificate downlink to the second terminal 4, and manage the revocation broadcast and multi-terminal synchronization. The second terminal 4 and the plurality of associated terminals are used to receive and parse the disclosure presentation credentials, render a subset of authorized attributes in the contact information display area, and perform multi-terminal incremental synchronization based on the CRDT structure.

[0039] like Figure 4 As shown, the system data interaction process is as follows: First terminal 1 sends a certificate issuance request to certificate issuance service 2 ①, and certificate issuance service 2 returns a verifiable certificate VC; First terminal 1 transmits an uplink association mapping request carrying the disclosure presentation certificate to server 3 ②; Server 3 sends the disclosure presentation certificate downlink to second terminal 4 ③; If second terminal 4 initiates a search request for the first identity subject ④, server 3 returns the certificate backlink based on the association mapping data item; If the first identity subject performs an active revocation operation, server 3 broadcasts a revocation event to second terminal 4 ⑤.

[0040] Those skilled in the art will understand that all or part of the processes in the above embodiments can be implemented by a computer program instructing related hardware. The program can be stored in a computer-readable storage medium. When executed, the program can include the processes of the embodiments of the above methods to implement the selective disclosure function of verifiable credentials described in this invention. The storage medium can be a magnetic disk, optical disk, read-only memory (ROM), or random access memory (RAM), etc.

[0041] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A method for synchronizing contact identification information across multiple terminals, characterized in that, A method applicable to a communication system including a first terminal, a second terminal, a server, and multiple associated terminals of the second terminal, the method comprising: The second terminal receives and parses the disclosure presentation certificate for the first identity subject. The disclosure presentation certificate is constructed by the first terminal based on the verifiable certificate VC and the disclosure strategy configured for the second terminal for selective disclosure. The second terminal maintains a set of local contact identity information using a conflict-free copy data type (CRDT) structure, and writes a subset of the authorization attributes from the disclosure presentation credential into the CRDT structure; In response to the local update of the second terminal, the second terminal transmits an incremental synchronization message to the server. The server acts as a synchronization hub, broadcasting the incremental synchronization message to other associated terminals of the second terminal; Each associated terminal receives and independently merges the incremental synchronization messages locally based on the CRDT structure, and converges to a consistent state using a preset conflict resolution strategy.

2. The method according to claim 1, characterized in that, The disclosure presentation credential is constructed by the first terminal calling the trusted credential issuance service of the communication platform to obtain the verifiable credential VC under the name of the first identity subject, and performing selective disclosure processing on the VC based on the disclosure policy configured for the second terminal. The disclosure presentation credential includes a subset of authorized attributes and a zero-knowledge scope proof for the real-name authentication status. When broadcasting the incremental synchronization message, the server's synchronization hub maintains a global state vector of the contact identity information set using the account identifier of the second terminal as an index.

3. The method according to claim 1 or 2, characterized in that, The CRDT structure is a CRDT Map structure, where each contact identification information entry in the set is represented by a CRDT node; the preset conflict resolution strategy is a Last-Write-Wins strategy based on version vectors or timestamps, or an unordered set OR-Set strategy based on unique identifiers.

4. The method according to claim 1 or 2, characterized in that, Each disclosure operation generates a disclosure ticket carrying a unique serial number and validity period; if the first identity entity performs an active cancellation operation or the disclosure strategy expires, the server generates a cancellation event and broadcasts the cancellation event to each terminal that has received the disclosure presentation certificate, and each terminal marks the corresponding contact identification information as invalid and stops rendering.

5. A multi-terminal incremental synchronization method for a set of contact identification information, characterized in that, The method, applied to a communication system including a second terminal and multiple associated terminals of the second terminal, and a server, includes: The second terminal maintains a set of contact identification information using a conflict-free copy data type (CRDT) structure, where each contact identification information entry is represented by a CRDT node. In response to a local write or update operation of the second terminal, the second terminal generates an incremental synchronization message and transmits it upstream to the server; The server maintains a global state vector of the contact identity information set using the account identifier of the second terminal as an index, and broadcasts the incremental synchronization message to other associated terminals of the second terminal; Each associated terminal receives the incremental synchronization message and independently merges the incremental updates locally based on the CRDT structure, without the need for a central coordinating node to resolve conflicts, thus converging to a consistent state.

6. The method according to claim 5, characterized in that, The CRDT node is either the Last-Write-Wins register (LWW-Register) or an unordered set (OR-Set) based on a unique identifier.

7. A method for processing contact identification information, characterized in that, Applied to a server, the method includes: Receive an association mapping request transmitted uplink from the first terminal, the association mapping request carrying the terminal identifier of the second terminal and the disclosure presentation certificate constructed by the first identity subject; Parse and verify the validity of the cryptographic signature of the disclosure presentation certificate and its unrevoked status. After successful verification, establish and persistently store the association mapping data item between the terminal identifier of the second terminal and the disclosure presentation certificate. The disclosure presentation certificate is sent down to the second terminal, which maintains the contact identity information set in a CRDT structure. As a synchronization hub, it receives incremental synchronization messages from the second terminal and broadcasts them to other associated terminals, coordinating multi-terminal CRDT data synchronization. In response to a revocation event, the revocation event is broadcast to each terminal that has received the disclosure presentation certificate; After the second terminal resets or deletes the association with the first identity subject, the associated stored disclosure presentation credentials are returned in response to the retrieval request.

8. A method for synchronizing contact identification information across multiple terminals, characterized in that, A communication system comprising a first terminal, a second terminal, and multiple terminals associated with the two, wherein the first terminal and the second terminal directly establish a secure communication connection for information exchange, the method comprising: The first terminal constructs a disclosure presentation credential based on the verifiable credential (VC) and disclosure strategy, and transmits the disclosure presentation credential directly to the second terminal via the secure communication connection. The second terminal maintains a set of contact identification information using a CRDT structure and writes it into a subset of authorization attributes; The second terminal and each associated terminal incrementally synchronize contact identity information in the network through the secure communication connection based on the CRDT structure, and converge to a consistent state based on a preset conflict resolution strategy.

9. A multi-terminal synchronization device for contact identification information, characterized in that, Applied to a terminal, the device includes: The interface rendering module 11 is used to render the first identity configuration interface, which is used to provide an entry point for disclosing the identity information of the first identity subject to the contact information display area corresponding to the second terminal. The credential acquisition module 12 is used to call the trusted credential issuance service of the communication platform to obtain the verifiable credential VC under the name of the first identity subject. The credential construction module 13 is used to perform selective disclosure processing on the VC based on the disclosure policy configured for the second terminal, and construct a disclosure presentation credential that contains only a subset of authorized attributes, wherein the disclosure presentation credential also includes a zero-knowledge scope proof for the real-name authentication status. The uplink module 14 is requested to transmit an association mapping request carrying the terminal identifier of the second terminal and the disclosure presentation certificate to the server. Downlink receiving module 15 is used to receive and parse the disclosure presentation certificate issued by the server; The information rendering module 16 is used to render and present the subset of authorized attributes parsed by the downlink receiving module 15 in the contact information display area; The revocation management module 17 is used to monitor information disclosure revocation events and mark the corresponding contact identification information as invalid. The multi-terminal synchronization module 18 is used to maintain a set of contact identification information in a CRDT structure and perform incremental synchronization with other associated terminals.

10. A multi-terminal synchronization system for contact identification information, characterized in that, It includes a first terminal, a second terminal, a server, and multiple associated terminals of the second terminal, wherein: The first terminal is used to call the trusted credential issuance service of the communication platform to obtain a verifiable credential (VC), construct a disclosure presentation credential based on the disclosure strategy, and transmit an association mapping request to the server. The server is used to verify the disclosure presentation credential, establish and persistently store associated mapping data items, send the disclosure presentation credential downlink, and act as a synchronization hub to coordinate multi-terminal CRDT data synchronization and revocation propagation. The second terminal and the plurality of associated terminals are used to receive and parse the disclosure presentation credentials, maintain a set of contact identity information in a CRDT structure, and independently merge and converge to a consistent state locally based on incremental synchronization messages.

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