Block chain identity certificate revocation method in 6G heterogeneous network scene

Abstract

The invention discloses a block chain identity certificate revocation method in a 6G heterogeneous network scene. Firstly, aiming at the problem that an existing identity revocation research scheme does not fully consider the problems of compatibility and interoperability possibly occurring in a heterogeneous network scene, the invention provides a four-layer identity revocation scheme architecture based on a block chain, and the problems of compatibility and interoperability of identity credential revocation of a heterogeneous network are solved. Aiming at the problem that an existing identity credential revocation scheme does not consider high-load challenges caused by access of massive users and terminal equipment to a 6G heterogeneous network, the requirements of the 6G network cannot be met in the aspects of safety and verification time delay. According to the method, a multi-accumulator mechanism based on dynamic extension and a load balancing algorithm is realized through the directional routing layer and the accurate judgment layer, the number of RSA accumulators can be automatically adjusted according to the number of revocation vouchers, and lower and more stable time delay required for verifying the revocation vouchers is realized.

Description

Technical Field

[0001] The present application relates to the field of mobile communication technology, and in particular to a method for revoking a blockchain identity certificate in a 6G heterogeneous network scenario. Background Art

[0002] In recent years, with the establishment of the IMT-2030 (6G) Promotion Group, an increasing number of experts and scholars have begun exploring and promoting the development of China's sixth-generation mobile communication technology. 6G networks, through the deep integration of cellular base stations, massive Internet of Things (IoT) terminals, and high-density wireless local area network (WLAN) access points, establish a "super-dense heterogeneous" three-dimensional coverage system. In 6G heterogeneous network scenarios, user devices need to frequently exchange information and resources, making identity authentication essential. Identity revocation plays a key role in heterogeneous network identity authentication. First, in terms of security, identity revocation is a crucial line of defense for network security. When a user's identity information is stolen or other security risks exist, timely identity revocation prevents unauthorized users from continuing to use that identity to access resources in heterogeneous networks, thus protecting the security of heterogeneous networks and data. Secondly, identity revocation is also crucial in the area of ​​permission management. Identity authentication is often closely linked to permission management, and identity revocation can precisely control user access to heterogeneous network resources. When users and terminal devices no longer need certain permissions or are no longer qualified to access specific resources in a heterogeneous network, their corresponding permissions can be immediately revoked through identity revocation.

[0003] However, existing identity revocation schemes fail to fully consider the compatibility and interoperability issues that may arise in heterogeneous network scenarios, making it difficult to maintain identity revocation information consistency across heterogeneous networks. Furthermore, the verification latency of revocation schemes is unsuitable for the massive accessibility of 6G heterogeneous networks. A related study proposes an identity certificate revocation scheme based on asymmetric cryptographic accumulators, distributing the cryptographic accumulators via a blockchain. This research is still ongoing, and the corresponding test simulation data has not yet been released. Another study proposes a blockchain-based certificate revocation management and status verification system, which uses extended fields in the X.509 certificate structure to describe the node and Bloom filter information of the revoked certificate. This scheme's revocation query process is cumbersome, and the query latency increases as the number of revoked certificates increases. Another study proposes an identity certificate revocation scheme based on a consortium blockchain and chameleon hashing. This scheme uses chameleon hashing to construct an editable blockchain and implements identity revocation by deleting identity certificates, replacing the existing append-only revocation scheme. While this scheme improves revocation retrieval latency and saves storage space, it also introduces issues such as compromised data integrity and immutability, loss of historical traceability, and difficulty maintaining consistency.

[0004] In summary, existing identity credential revocation schemes are designed for a single technology-based network architecture, failing to fully consider the compatibility and interoperability issues that may arise in heterogeneous network scenarios with multiple technologies. The schemes are overly simplistic. Furthermore, they fail to account for the high load challenges posed by massive user and terminal device access to 6G heterogeneous networks, failing to meet the security and verification latency requirements of 6G networks. They only consider the case of a unidirectional increase in the number of elements, lack a dynamic load balancing algorithm, and are unable to adapt to 6G heterogeneous network scenarios where users and terminal devices frequently enter and exit. Summary of the Invention

[0005] This application proposes a blockchain identity credential revocation method for 6G heterogeneous network scenarios. First, a four-layer architecture consisting of a fast pre-filtering layer, a directional routing layer, a precise judgment layer, and a trusted storage layer is proposed. The fast pre-filtering layer intercepts verification requests for unrevoked credentials. The directional routing layer and the precise judgment layer implement a multi-accumulator mechanism based on a dynamic expansion and load balancing algorithm, which automatically adjusts the number of RSA accumulators based on the number of revoked credentials. Finally, the latest accumulated value of the RSA accumulator in the precise judgment layer is uploaded to the trusted storage chain, improving the security of identity credential revocation operations and reducing the delay required to verify revoked credentials.

[0006] The present application provides a blockchain identity credential revocation method in a 6G heterogeneous network scenario, which is characterized by comprising:

[0007] Build a 6G heterogeneous network identity credential revocation scheme BCMRA with a four-layer architecture model, including a fast pre-filtering layer, a directional routing layer, a precise judgment layer, and a trusted storage layer;

[0008] Determine the step-by-step operation strategy for revoking identity credentials at the fast pre-filtering layer, the directional routing layer, the precise judgment layer, and the trusted storage layer according to the identity credential revocation scheme BCMRA;

[0009] When the user identity credential revocation meets the triggering conditions, the 6G heterogeneous network identity credential revocation operation is performed with the user's credential identifier as the operation object according to the identity credential revocation step-by-step operation strategy of the fast pre-filtering layer, the directional routing layer, the precise judgment layer, and the trusted storage layer; the identity credential revocation triggering conditions include active credential revocation and passive credential revocation;

[0010] After completing the 6G heterogeneous network identity credential revocation operation, verify whether the user identity credential has been revoked.

[0011] Furthermore, the 6G heterogeneous network identity credential revocation scheme BCMRA adopts RSA accumulator as the minimum verification unit. When verifying the existence of a member through RSA accumulator, the prerequisite for achieving O(1) time complexity is that a certain element x is known. iMembership certificate ω i , when a member joins or leaves the RSA accumulator, the element x i Membership certificate ω i Updated to ω i , its time complexity is O(n), which is linearly related to the number of members in the accumulator. When a member joins or leaves the accumulator, the proofs of other members in the accumulator are updated during verification. Specifically, when a member in the accumulator changes, the member proofs of other members are not updated first. When other members apply for verification, the proof of this member is updated separately. i , and the time complexity is O(n).

[0012] Furthermore, the fast pre-filtering layer uses a cuckoo filter to store the identifier ID of the revoked user credentials cred , intercept verification requests for unrevoked credentials:

[0013] The basic structure of the cuckoo filter includes a bucket array, a fingerprint f, and candidate bucket functions b1 and b2. The bucket array consists of multiple buckets, each bucket contains several slots, and a slot can store a fingerprint f. Each bucket in the bucket array can store 4 fingerprints. The fingerprint f is the short hash value of the element. The candidate bucket function is used to calculate the two candidate bucket positions corresponding to the element x, where the position i1=b1(x).

[0014] Calculate the fingerprint f of element x and the two candidate bucket positions i1 and i2, check whether there are empty slots in the buckets corresponding to i1 and i2, and if one of the buckets has an empty slot, store f in the empty slot and the insertion is successful. If both buckets are full, randomly select a fingerprint from one bucket and kick it out. The fingerprint of the kicked element is then tried to be inserted into another possible position i2. Repeat this process until the insertion is successful or the maximum number of attempts is reached;

[0015] Calculate the fingerprint f of element x and the two candidate bucket positions i1 and i2, check whether the slots in the buckets corresponding to i1 and i2 contain fingerprint f. If the slot of one of the buckets contains f, it is considered that element x may exist in the filter; if all slots of the two buckets do not contain fingerprint f, it can be determined that element x does not exist in the filter.

[0016] Furthermore, the directional routing layer is responsible for sending the identifier ID of the revoked user credential to cred Mapped to the corresponding RSA accumulator number, the consistent hashing algorithm is used as the method for routing RSA accumulator selection. The consistent hashing algorithm mapping design process is as follows:

[0017] 1) Consistent hash ring initialization

[0018] (a) Define the hash space: Select SHA-256 as the hash function, and the hash space range is [0,2 256 -1], forming a logical closed loop space;

[0019] (b) Deploy virtual nodes: Each RSA accumulator corresponds to V virtual nodes vnode, and the virtual node hash value H vnode The calculation formula is:

[0020] H vnode =H(Acc id +Replica id )

[0021] Among them, Replica id Is the virtual node replica serial number, the value range is [0, V-1], Acc id is the number of the accumulator;

[0022] (c) Build a hash ring: H is the hash value of all virtual nodes vnode Sorting to form a consistent hash ring, each virtual node is responsible for the corresponding interval, where is the hash value of the virtual node itself, is the hash value of the next virtual node after sorting;

[0023] 2) Mapping rule design

[0024] (a) Locating the virtual node: Calculating the identifier of the credential to be revoked cred The hash value H cred , get the ID cred The position in the consistent hash ring, starting from this position along the consistent hash ring clockwise search, find the first hash value greater than H cred Virtual node vnode m , vnode m satisfy:

[0025]

[0026] (b) Mapping RSA accumulator: Locating to virtual node vnode m The physical node corresponding to the virtual node is the target RSA accumulator. The physical node represented by an RSA accumulator corresponds to multiple virtual nodes. By increasing the number of virtual nodes, the virtual nodes are evenly distributed on the consistent hash ring, so that the credential identifier ID to be revoked cred More evenly distributed across the RSA accumulators.

[0027] Furthermore, the precise judgment layer is responsible for storing the identifier ID of the revoked user credentialscred , processing the verification request of the revoked user credentials, the precise judgment layer contains a set of k RSA accumulators {Acc1,Acc2,…,Acc k}, initialized with uniform parameters (p, q, N, g), with the same initial accumulator value Acc0, where p and q are large prime numbers, N = pq, g is the generator, and the i-th RSA accumulator contains a number n i A collection of elements Each element corresponds to the identifier ID of a revoked user credential cred , the accumulated value of the i-th RSA accumulator is expressed as:

[0028]

[0029] When the RSA accumulator Acc i When changes occur due to adding or deleting elements, it also exists in the RSA accumulator Acc i Elements No need to renew membership certificate immediately Instead, regenerate the latest membership certificate when applying for verification

[0030]

[0031] Where j represents the j-th element in the RSA accumulator i; z represents the numbers of all elements in the RSA accumulator i except the j-th element.

[0032] Furthermore, the precise judgment layer also includes dynamically adjusting the number of RSA accumulators and transferring and revoking user credentials through dynamic expansion and load balancing algorithms, specifically:

[0033] When the number of revoked certificates stored in any RSA accumulator exceeds the maximum load threshold Load max , trigger the operation of adding a new RSA accumulator, add a new RSA accumulator with the same initialization parameters, generate the corresponding virtual node and insert it into the consistent hash ring, start from the position of the new RSA accumulator on the hash ring, find the next RSA accumulator in the clockwise direction, and migrate the revocation certificates between the two RSA accumulators to the new RSA accumulator;

[0034] When the number of revoked certificates stored in any RSA accumulator is lower than the minimum load threshold min , triggering the operation of reducing the RSA accumulator, removing all virtual nodes of the RSA accumulator from the consistent hash ring, and then finding all the credentials originally mapped to the RSA accumulator, recalculating the hash values ​​of these credentials, and mapping them to the new RSA accumulator.

[0035] Furthermore, the trusted storage layer is responsible for storing the latest accumulated value Acc of each RSA accumulator in the accurate judgment layer. i 、Acc i , the verifier in the trust domain X automatically uploads it to the blockchain network maintained by each node in the trust domain X in the form of a transaction through a smart contract.

[0036] Furthermore, if the identity credential revocation trigger condition is active credential revocation, the specific steps for revoking the 6G heterogeneous network identity credential are as follows:

[0037] User A initiates a credential revocation request to the verifier in the same trust domain X. The request contains the user's identifier and credential ID. cred , encrypted with the verifier’s public key;

[0038] After receiving the active credential revocation request from user A, the verifier uses the private key to verify the legitimacy of the request;

[0039] The verifier parses the user's identity and credential information from the request and verifies the user's legitimacy in the blockchain within the local domain;

[0040] After the user A's active credential revocation request, identity information and credential information are verified, the verifier will send the user A's credential identifier ID cred Send to the cuckoo filter of the fast pre-filtration layer;

[0041] Cuckoo filter performs insert element operation and calculates the credential identifier ID cred The fingerprint and candidate bucket position are inserted into the corresponding slot;

[0042] Further, the credential identifier ID cred Send it to the directional routing layer, where the target RSA accumulator number is calculated using the consistent hashing algorithm;

[0043] According to the calculated target RSA accumulator number, the credential identifier ID cred Send to the accurate judgment layer;

[0044] In the precise judgment layer, the RSA accumulator performs the element insertion operation to generate the latest accumulated value;

[0045] The blockchain node in the trusted storage layer writes the latest accumulated value of the RSA accumulator to the blockchain network in the form of a smart contract transaction, completing the certificate revocation operation for user A;

[0046] The blockchain node returns the certificate revocation result to user A's client.

[0047] Furthermore, if the identity credential revocation trigger condition is passive credential revocation, the specific steps for revoking the 6G heterogeneous network identity credential are as follows:

[0048] After user B in trust domain X commits a malicious act, the trust management committee member from trust domain X checks whether user B's comprehensive trust value is lower than the minimum trust threshold of trust domain X, and requests the trust management blockchain node to query and calculate user B's comprehensive trust value;

[0049] The trust management blockchain node calculates the comprehensive trust value based on the user B's identity identifier and the trust domain X identifier through the node trust evaluation scheme;

[0050] The trust management blockchain node sends the comprehensive trust value of user B to the members of the trust management committee;

[0051] The Trust Management Committee members determine whether user B's credentials need to be revoked based on the returned comprehensive trust value;

[0052] If the judgment result is that the credentials of user B need to be passively revoked, the credential identifier ID of user B will be cred Sent to the cuckoo filter in the fast pre-filtration layer.

[0053] Cuckoo filter performs insert element operation and calculates the credential identifier ID cred The fingerprint and candidate bucket position are inserted into the corresponding slot;

[0054] Further, the credential identifier ID cred Send to the directional routing layer to avoid misjudgment of revoked credential verification;

[0055] The target RSA accumulator number is calculated by consistent hashing algorithm in the directional routing layer;

[0056] According to the calculated target RSA accumulator number, the credential identifier ID cred Send to the accurate judgment layer;

[0057] In the precise judgment layer, the RSA accumulator performs the element insertion operation to generate the latest accumulated value;

[0058] The blockchain node in the trusted storage layer writes the latest accumulated value of the RSA accumulator to the blockchain network in the form of a smart contract transaction, completing the certificate revocation operation for user B;

[0059] The blockchain node returns the certificate revocation result to user B's client.

[0060] Furthermore, the specific steps of verifying whether the user identity certificate has been revoked are:

[0061] The verifier first performs a quick verification operation, calling the query element interface of the Cuckoo filter;

[0062] The Cuckoo filter performs the query element operation, and the input parameter is the credential identifier ID to be verified cred The output query result is whether the credential identifier ID exists or not cred ;

[0063] If the verification result received by the verifier is the credential identifier ID cred If it does not exist, the verification process ends and the result of the credential to be verified has not been revoked is obtained; if the verification result received is the credential identifier ID cred If it exists, continue to execute the subsequent steps;

[0064] The verifier sends a request for accurate verification to the blockchain node in the local domain, and the request contains the credential identifier ID cred , and encrypted with the validator's private key;

[0065] The blockchain node verifies the legitimacy of the request through the validator's public key, and then calculates the ID of the target RSA accumulator through the consistent hashing algorithm. acc ;

[0066] The blockchain node queries the latest accumulated value Acc of the accumulator through the target RSA accumulator number. i , generate the latest membership proof ω, and send the latest accumulated value and membership proof to the verifier;

[0067] The verifier verifies the validity of the latest member certificate ω through the verification parameters returned by the blockchain node, and finally completes the entire process of verifying whether the user credentials have been revoked.

[0068] At least one of the above technical solutions adopted in the embodiments of the present application can achieve the following beneficial effects:

[0069] 1. The present invention designs a four-layer architecture model BCMRA for 6G heterogeneous network identity credential revocation, which divides the related operations of identity credential revocation into functional groups and handles them by different technologies and algorithms in different layers. This decoupled design can improve the interoperability of identity credential revocation solutions in heterogeneous networks.

[0070] 2. The present invention comprehensively analyzes the advantages and disadvantages of different member proof update mechanisms in 6G heterogeneous wireless network scenarios from the three perspectives of real-time requirements, resource consumption, and network communication burden, and proposes a member proof verification update mechanism that is more suitable for 6G heterogeneous wireless network scenarios.

[0071] 3. The present invention uses the BCMRA fast pre-filtering layer to quickly intercept verification requests for unrevoked credentials, which can reduce the load pressure of requests for verifying whether identity credentials are revoked in large-scale access 6G heterogeneous network scenarios.

[0072] 4. The present invention designs a multi-accumulator mechanism based on dynamic expansion and load balancing algorithm through the BCMRA directional routing layer and the BCMRA precise judgment layer, which can dynamically adjust the number of RSA accumulators when the number of revoked certificates increases or decreases, thereby achieving a smaller and more stable verification and revocation delay.

[0073] 5. The present invention uses the BCMRA trusted storage layer and the 6G heterogeneous network identity credential verification and revocation method to store the latest accumulated value of the RSA accumulator on the chain, thereby improving the security of identity credential revocation and simplifying the process of verifying and revoking credentials.

[0074] 6. The present invention enriches the revocation scheme and applicability through the 6G heterogeneous network active credential revocation and passive credential revocation scheme and process, gives users and terminal devices the authority to independently control their identity credentials, protects user autonomy, and enhances the security of heterogeneous networks. BRIEF DESCRIPTION OF THE DRAWINGS

[0075] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0076] Figure 1 This is a flowchart of 6G heterogeneous network identity certificate revocation provided by an embodiment of the present invention.

[0077] Figure 2 This is the architecture diagram of the 6G heterogeneous network identity credential revocation BCMRA solution provided by an embodiment of the present invention.

[0078] Figure 3 Schematic diagram of a cuckoo filter in a rapid pre-filtration layer provided by an embodiment of the present invention.

[0079] Figure 4 This is a flow chart of user-initiated credential revocation provided by an embodiment of the present invention.

[0080] Figure 5 This is a flowchart of passive revocation of user credentials provided by an embodiment of the present invention.

[0081] Figure 6 This is a flow chart of verifying user certificate revocation provided by an embodiment of the present invention.

[0082] Figure 7 This is a diagram of the load balancing simulation results of the BCMRA solution provided by an embodiment of the present invention.

[0083] Figure 8 This is a load balancing result diagram of 5,000 revoked certificates provided by an embodiment of the present invention.

[0084] Figure 9 This is a comparison chart of the delay in querying revoked credentials provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0085] To make the purpose, technical solutions, and advantages of this application more clear, the technical solutions of this application will be clearly and completely described below in conjunction with the specific embodiments of this application and the corresponding drawings. Obviously, the embodiments described are only part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0086] The following describes in detail the technical solutions provided by various embodiments of the present application in conjunction with the accompanying drawings.

[0087] like Figure 1 As shown, the embodiment of the present application provides a blockchain identity certificate revocation method in a 6G heterogeneous network scenario, including:

[0088] Step S1: constructing a 6G heterogeneous network identity credential revocation scheme BCMRA with a four-layer architecture model, wherein the four-layer architecture includes a fast pre-filtering layer, a directional routing layer, a precise judgment layer, and a trusted storage layer;

[0089] Step S2: Determine the step-by-step operation strategy for identity credential revocation of the fast pre-filtering layer, the directional routing layer, the precise judgment layer, and the trusted storage layer according to the identity credential revocation scheme BCMRA;

[0090] Step S3: When the user identity credential revocation meets the triggering conditions, the 6G heterogeneous network identity credential revocation operation is performed with the user's credential identifier as the operation object according to the identity credential revocation step-by-step operation strategy of the fast pre-filtering layer, the directional routing layer, the precise judgment layer, and the trusted storage layer; the identity credential revocation triggering conditions include active credential revocation and passive credential revocation;

[0091] Step S4: After completing the 6G heterogeneous network identity credential revocation operation, verify whether the user identity credential has been revoked.

[0092] In this embodiment, the 6G heterogeneous network identity credential revocation scheme BCMRA uses RSA accumulator as the minimum verification unit. When verifying the existence of a member through RSA accumulator, the prerequisite for achieving O(1) time complexity is that a certain element x is known. i Membership certificate ω i, when a member joins or leaves the RSA accumulator, the element x i Membership certificate ω i Need to update to ω i Its time complexity is O(n), which is linear with the number of members in the accumulator. When a member joins or leaves the accumulator, the proofs of other members in the accumulator are updated in the following two ways:

[0093] (1) Immediate update: When a member in the accumulator changes, the system immediately calculates and generates a new membership certificate ω for other members in the accumulator. i , the time complexity is O(n 2 ). The time complexity of other member verification is O(1).

[0094] (2) Update during verification: When a member joins or leaves the accumulator, the proofs of other members in the accumulator are updated during verification. Specifically, when a member in the accumulator changes, the system does not update the membership proofs of other members first, but updates the proof of the member alone when other members apply for verification. i , and the time complexity is O(n).

[0095] The two aforementioned accumulator membership proof update methods each have their own advantages and disadvantages. The immediate update mechanism offers greater real-time performance, ensuring that all membership proofs in the system are always up-to-date and valid. However, this comes at the cost of exponentially increasing time complexity and significant consumption of system computational and time resources. The verification-based update mechanism offers less real-time performance, with the computational complexity of each update linearly proportional to the number of members, resulting in relatively low overall resource consumption.

[0096] In 6G heterogeneous wireless network scenarios, the number of users and terminal devices is huge. Considering the real-time requirements, resource consumption, and network communication burden, the membership proof verification update mechanism is more suitable for 6G heterogeneous wireless network scenarios. This paper proposes a credential revocation and verification revocation scheme (BCMRA) based on blockchain, cuckoo filter, consistent hash routing technology, and RSA multi-accumulator. Figure 2 This is the architecture diagram of the BCMRA solution for 6G heterogeneous network identity credential revocation provided by an embodiment of the present invention. The BCMRA solution is divided into a four-layer architecture according to different functions, including a fast pre-filtering layer, a directional routing layer, a precise judgment layer, and a trusted storage layer from the top layer to the bottom.

[0097] In step S1, the fast pre-filtering layer uses a cuckoo filter to store the identifier ID of the revoked user credentials cred, intercepting verification requests for unrevoked credentials. Cuckoo filters have a certain error rate when determining whether an element exists in a collection. However, compared to precise data structure arrays, cuckoo filters can store more element information in less space, improving space utilization and query efficiency. Cuckoo filters support element deletion, and have lower time complexity for inserting, deleting, and querying elements, making them more suitable for the highly dynamic 6G heterogeneous network scenarios. Figure 3 This is a schematic diagram of the cuckoo filter in the rapid pre-filtration layer of the present invention. The basic structure and basic operating principle of the cuckoo filter are introduced below:

[0098] (a) Basic structure: The basic structure of the cuckoo filter includes a bucket array, a fingerprint f, and candidate bucket functions b1 and b2. The bucket array consists of multiple buckets, each bucket contains several slots, and a slot can store a fingerprint f. Each bucket in the bucket array can store 4 fingerprints. The fingerprint f is the short hash value of the element. The candidate bucket function is used to calculate the two candidate bucket positions corresponding to the element x, where the position i1 = b1(x).

[0099] (b) Inserting an element: Calculate the fingerprint f of element x and the two candidate bucket positions i1 and i2. Check whether there are empty slots in the buckets corresponding to i1 and i2. If there is an empty slot in one of the buckets, store f in the empty slot and the insertion is successful. If both buckets are full, randomly select a fingerprint from one bucket and kick it out. The fingerprint of the kicked element is then tried to be inserted according to its other possible position i2. Repeat this process until the insertion is successful or the maximum number of attempts is reached.

[0100] (c) Querying an element: Calculate the fingerprint f of element x and the two candidate bucket positions i1 and i2. Check whether the slots in the buckets corresponding to i1 and i2 contain fingerprint f. If one of the slots in the buckets contains f, element x is considered likely to be in the filter. If no slots in either bucket contain fingerprint f, element x is definitely not in the filter. Because different elements may have the same fingerprint, the query results may contain misjudgments.

[0101] Because the Cuckoo filter can misjudge, the BCMRA solution cannot use only the output of a Cuckoo filter to determine whether a user's credentials have been revoked. On the contrary, the Cuckoo filter can quickly determine whether a user's credentials have been revoked and effectively intercept verification requests for unrevoked credentials.

[0102] The directional routing layer is responsible for sending the identifier ID of the revoked user credentials to credMapped to the corresponding RSA accumulator number, the number of RSA accumulators in the BCMRA scheme changes dynamically according to the number of elements. Therefore, in addition to satisfying the one-to-one relationship, the mapping algorithm of the directional routing layer should also reduce the number of elements that need to be remapped when the number of RSA accumulators changes. The simple modulo hash algorithm is represented by hash(ID cred )modk, where k is the number of RSA accumulators. When the number of RSA accumulators decreases or increases to k, almost all RSA accumulator elements need to have their hash values ​​recalculated and migrated. The consistent hashing algorithm maps each RSA accumulator to a virtual ring space. When an RSA accumulator is added or deleted, only the adjacent elements in the ring space need to be remapped. Therefore, the directional routing layer uses the consistent hashing algorithm as the method for routing RSA accumulators. The consistent hashing algorithm mapping design process is as follows:

[0103] 1) Consistent hash ring initialization

[0104] (a) Define the hash space: Select SHA-256 as the hash function, and the hash space range is [0,2 256 -1], forming a logical closed loop space;

[0105] (b) Deploy virtual nodes: Each RSA accumulator corresponds to V virtual nodes vnode, and the virtual node hash value H vnode The calculation formula is:

[0106] H vnode =H(Acc id +Replica id )

[0107] Among them, Replica id Is the virtual node replica serial number, the value range is [0, V-1], Acc id is the number of the accumulator;

[0108] (c) Build a hash ring: H is the hash value of all virtual nodes vnode Sorting to form a consistent hash ring, each virtual node is responsible for the corresponding interval, where is the hash value of the virtual node itself, is the hash value of the next virtual node after sorting;

[0109] 2) Mapping rule design

[0110] (a) Locating the virtual node: Calculating the identifier of the credential to be revoked cred The hash value H cred , get the ID credThe position in the consistent hash ring, starting from this position along the consistent hash ring clockwise search, find the first hash value greater than H cred Virtual node vnode m , vnode m satisfy:

[0111]

[0112] (b) Mapping RSA accumulator: Locating to virtual node vnode m The physical node corresponding to the virtual node is the target RSA accumulator. The physical node represented by an RSA accumulator corresponds to multiple virtual nodes. By increasing the number of virtual nodes, the virtual nodes are evenly distributed on the consistent hash ring, so that the credential identifier ID to be revoked cred More evenly distributed across the RSA accumulators.

[0113] The precise judgment layer is responsible for storing the identifier ID of revoked user credentials cred , to handle verification requests for revoked user credentials, the core of the BCMRA solution is the multi-accumulator mechanism based on dynamic expansion and load balancing algorithm. The following will explain the multi-accumulator mechanism and dynamic expansion and load balancing respectively.

[0114] 1) Multi-layer accumulation mechanism:

[0115] The precise judgment layer contains a set of k RSA accumulators {Acc1,Acc2,…,Acc k}, initialized with uniform parameters (p, q, N, g), with the same initial accumulator value Acc0, where p and q are large prime numbers, N = pq, g is the generator, and the i-th RSA accumulator contains a number n i A collection of elements Each element corresponds to the identifier ID of a revoked user credential cred , the accumulated value of the i-th RSA accumulator is expressed as:

[0116]

[0117] When the RSA accumulator Acc i When changes occur due to adding or deleting elements, it also exists in the RSA accumulator Acc i Elements No need to renew membership certificate immediately Instead, regenerate the latest membership certificate when applying for verification

[0118]

[0119] Where j represents the j-th element in the RSA accumulator i; z represents the numbers of all elements in the RSA accumulator i except the j-th element.

[0120] 2) Dynamic expansion and load balancing algorithm

[0121] The static RSA accumulator solution has limitations. When the number of revoked users is still small, the number of elements in the RSA accumulator is small, and there may even be idle RSA accumulators, resulting in a waste of system space resources. A notable feature of the 6G heterogeneous network scenario is the high upper limit of the number of connected users and terminal devices. When the number of revoked users reaches a large scale, the number of elements in a single RSA accumulator is too large, and it takes a lot of time to generate new membership certificates when verifying the revocation. Therefore, a dynamic expansion and load balancing algorithm is proposed to dynamically adjust the number of RSA accumulators and transfer revoked user credentials. Specifically:

[0122] (a) New RSA accumulator: When the number of revoked certificates stored in any RSA accumulator exceeds the maximum load threshold max , trigger the operation of adding a new RSA accumulator, add a new RSA accumulator with the same initialization parameters, generate the corresponding virtual node and insert it into the consistent hash ring, start from the position of the new RSA accumulator on the hash ring, find the next RSA accumulator in the clockwise direction, and migrate the revocation certificates between the two RSA accumulators to the new RSA accumulator;

[0123] (b) Reduce RSA accumulators: When the number of revoked certificates stored in any RSA accumulator is lower than the minimum load threshold min , triggering the operation of reducing the RSA accumulator, removing all virtual nodes of the RSA accumulator from the consistent hash ring, and then finding all the credentials originally mapped to the RSA accumulator, recalculating the hash values ​​of these credentials, and mapping them to the new RSA accumulator.

[0124] (2) Trusted storage layer:

[0125] The trusted storage layer is responsible for storing the latest accumulated value Acc of each RSA accumulator in the accurate judgment layer i 、Acc i , the verifier in the trust domain X automatically uploads it to the blockchain network maintained by each node in the trust domain X in the form of a transaction through a smart contract.

[0126] In this embodiment, the identity credential revocation triggering conditions in step S3 include active credential revocation and passive credential revocation, specifically:

[0127] 1) Active credential revocation: The user submits an application to revoke the identity credential on their own initiative.

[0128] 2) Passive credential revocation: The user's identity credential expires or the user engages in malicious behavior, causing the comprehensive trust value to drop. The system detects that the user's comprehensive trust value is lower than the minimum tolerance limit of trust domain X.

[0129] like Figure 4 As shown, the specific steps of the user's active certificate revocation process are as follows:

[0130] Step 1: User A initiates a credential revocation request to the verifier in the same trust domain X. The request contains the user's identifier and credential ID. cred , encrypted with the verifier’s public key;

[0131] Step 2: After receiving the active credential revocation request from user A, the verifier uses the private key to verify the legitimacy of the request;

[0132] Step 3: The verifier parses the user's identity and credential information from the request and verifies the user's legitimacy in the blockchain within the local domain;

[0133] Step 4: After the request of user A in step 1, the identity information in step 2, and the credential information in step 3 are verified, the verifier will send the credential identifier ID of user A to cred Send to the cuckoo filter of the fast pre-filtration layer;

[0134] Step 5: Cuckoo filter performs the insert element operation and calculates the ID cred The fingerprint and candidate bucket position are inserted into the corresponding slot;

[0135] Step 6: To avoid misjudgment of revoked credentials, further cred Sent to the directional routing layer,

[0136] Step 7: Calculate the target RSA accumulator number using the consistent hashing algorithm in the directional routing layer;

[0137] Step 8: According to the calculated target RSA accumulator number, further ID cred Send to the accurate judgment layer;

[0138] Step 9: In the precise judgment layer, the RSA accumulator performs the element insertion operation to generate the latest accumulated value;

[0139] Step 10: The blockchain node in the trusted storage layer writes the latest accumulated value of the RSA accumulator to the blockchain network in the form of a smart contract transaction, completing the certificate revocation operation for user A;

[0140] Step 11: The blockchain node returns the certificate revocation result to user A's client.

[0141] The passive revocation process of user credentials is different from the process of user active revocation of credentials in the trigger judgment stage. Steps 5 to 12 in the passive revocation process of user credentials are consistent with steps 4 to 11 in the process of user active revocation of credentials, and both adopt the BCMRA scheme proposed by the present invention. Therefore, the following describes steps 1 to 4 in the passive revocation process of user credentials. Figure 5 As shown, the specific steps of the user passive certificate revocation process are as follows:

[0142] Step 1: After user B in trust domain X commits a malicious act, the trust management committee member from trust domain X checks whether user B's comprehensive trust value is lower than the minimum trust threshold of trust domain X, and requests the trust management blockchain node to query and calculate user B's comprehensive trust value;

[0143] Step 2: The trust management blockchain node calculates the comprehensive trust value based on the user B's identity identifier and the trust domain X identifier using the node trust evaluation scheme;

[0144] Step 3: The trust management blockchain node sends the comprehensive trust value of user B to the members of the trust management committee;

[0145] Step 4: Determine with the Trust Management Committee members whether user B's credentials need to be revoked based on the returned comprehensive trust value;

[0146] Step 5: If the result is that the credentials of user B need to be passively revoked, the credential identifier ID of user B will be cred Sent to the cuckoo filter in the fast pre-filtration layer.

[0147] Step 6: Cuckoo filter performs the insert element operation and calculates the ID cred The fingerprint and candidate bucket position are inserted into the corresponding slot;

[0148] Step 7: Further ID cred Send to the directional routing layer to avoid misjudgment of revoked credential verification;

[0149] Step 8: Calculate the target RSA accumulator number using the consistent hashing algorithm in the directional routing layer;

[0150] Step 9: Based on the calculated target RSA accumulator number, further convert the ID cred Send to the accurate judgment layer;

[0151] Step 10: In the precise judgment layer, the RSA accumulator performs the element insertion operation to generate the latest accumulated value;

[0152] Step 11: The blockchain node in the trusted storage layer writes the latest accumulated value of the RSA accumulator to the blockchain network in the form of a smart contract transaction, completing the certificate revocation operation for user B.

[0153] Step 12: The blockchain node returns the certificate revocation result to user B's client.

[0154] like Figure 6 As shown in the figure, it is a flow chart of verifying user revoking credentials in step S4, and the process is as follows:

[0155] Verifying and revoking credentials is an important part of the 6G heterogeneous network identity authentication solution. When verifying the legitimacy of the user identity and the validity of the user credentials, the verifier must first verify whether the user credentials have been revoked. Only after confirming that the user credentials have not been revoked can further operations be performed. In the 6G heterogeneous network identity credential verification and revocation method, the specific steps of the process for the verifier to verify whether the user credentials have been revoked are as follows:

[0156] The verifier first performs a quick verification operation, calling the query element interface of the Cuckoo filter;

[0157] The Cuckoo filter performs a query element operation, and the input parameter is the ID to be verified cred , output query result is whether ID exists or not cred ;

[0158] If the verification result received by the verifier is ID cred If it does not exist, the verification process ends and the result of the credential to be verified has not been revoked is obtained; if the verification result received is ID cred If it exists, continue to execute the subsequent steps;

[0159] The verifier sends a request for accurate verification to the blockchain node in the local domain, and the request contains the ID cred , and encrypted with the validator's private key;

[0160] The blockchain node verifies the legitimacy of the request through the validator's public key, and then calculates the target RSA accumulator ID through the consistent hashing algorithm. acc ;

[0161] The blockchain node queries the latest accumulated value Acc of the accumulator through the number of the target RSA accumulator. i , generate the latest membership proof ω, and send the latest accumulated value and membership proof to the verifier;

[0162] The verifier verifies the validity of the latest member certificate ω through the verification parameters returned by the blockchain node, and finally completes the entire process of verifying whether the user credentials have been revoked.

[0163] In the most ideal case, the BCMRA scheme only needs one query element operation to complete the verification. Even if a second precise verification is required, the BCMRA scheme proposed in the present invention can still reduce the delay required for verification revocation.

[0164] like Figure 7 The following table shows the load balancing simulation results of the BCMRA solution. The maximum load threshold of the BCMRA solution is Load max Set to 550, the number of virtual nodes vnode V corresponding to each RSA accumulator is set to 5000. The curve represents the total time consumed for load balancing as the number of revoked certificates increases, corresponding to the vertical axis on the left. The bar chart represents the total number of certificates that need to be migrated, corresponding to the vertical axis on the right. The time consumed for load balancing is the time consumed for migrating certificates. When the number of revoked certificates is 1000, there are 2 RSA accumulators in the precise judgment layer and load balancing is not required. As the number of revoked certificates increases to 1500, the number of elements stored in the RSA accumulator exceeds the maximum load threshold Load. max BCMRA initiates load balancing, dynamically increases the number of RSA accumulators to three, and transfers some of the credentials. As the number of revoked credentials increases from 1000 to 1500, the time required for load balancing is calculated as the value of the curve at 1500 minus the value of the curve at 1000. As can be seen, the time required for each load balancing execution by the BCMRA solution remains essentially unchanged as the number of revoked credentials increases.

[0165] like Figure 8 As shown in the figure, when the number of revoked certificates reaches 5000, the number of RSA accumulators in the precise judgment layer is 10, and the maximum difference in the number of revoked certificates stored in each RSA accumulator is only 40. Although it does not achieve completely even distribution, the BCMRA scheme proposed in the present invention can ensure relatively uniform load balancing.

[0166] like Figure 9The figure shows the time required to check whether a credential has been revoked. The curve through the squares in the figure is the test result of the original solution. When only a single RSA accumulator is used to store revoked credentials, the verification latency increases linearly with the number of stored credentials. The curve through the triangles in the figure shows the query latency of BCMRA. Thanks to the BCMRA load balancing algorithm, the query latency remains relatively stable even when the number of revoked credentials increases. Under normal circumstances, most revocation query requests are not initiated simultaneously with load balancing. The system can complete load balancing when there are no requests or the request volume is low. However, during peak hours, simultaneous load balancing and revocation query operations cannot be ruled out. The curve through the circles in the figure shows the latency when load balancing and revocation query operations are performed simultaneously. It can be seen that even if a revocation query operation is performed immediately after load balancing, the total latency is still lower than the original solution and can be controlled within 1 second. This will not cause noticeable system lag in 6G heterogeneous network scenarios with a large number of users and terminal devices.

[0167] The foregoing is merely an embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various changes and variations. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present application should all be included within the scope of the claims of the present application.

Claims

1. A blockchain identity certificate revocation method in a 6G heterogeneous network scenario, characterized in that: include: Build a 6G heterogeneous network identity credential revocation scheme BCMRA with a four-layer architecture model, including a fast pre-filtering layer, a directional routing layer, a precise judgment layer, and a trusted storage layer; Determine the step-by-step operation strategy for revoking identity credentials at the fast pre-filtering layer, the directional routing layer, the precise judgment layer, and the trusted storage layer according to the identity credential revocation scheme BCMRA; When the user identity credential revocation meets the triggering conditions, the 6G heterogeneous network identity credential revocation operation is performed with the user's credential identifier as the operation object according to the identity credential revocation step-by-step operation strategy of the fast pre-filtering layer, the directional routing layer, the precise judgment layer, and the trusted storage layer; the identity credential revocation triggering conditions include active credential revocation and passive credential revocation; After completing the 6G heterogeneous network identity credential revocation operation, verify whether the user identity credential has been revoked.

2. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 1 is characterized in that: The 6G heterogeneous network identity credential revocation scheme BCMRA adopts RSA accumulator as the minimum verification unit. When verifying the existence of a member through RSA accumulator, the prerequisite for achieving O(1) time complexity is that a certain element x is known. i Membership certificate ω i , when a member joins or leaves the RSA accumulator, the element x i Membership certificate ω i Updated to ω i `, its time complexity is O(n), which is linearly related to the number of members in the accumulator. When a member joins or leaves the accumulator, the proofs of other members in the accumulator are updated during verification. Specifically: when a member in the accumulator changes, the member proofs of other members are not updated first. When other members apply for verification, the proof of this member is updated separately. i , and the time complexity is O(n).

3. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 1 is characterized in that: The fast pre-filtering layer uses a cuckoo filter to store the identifier ID of revoked user credentials cred , intercept verification requests for unrevoked credentials: The basic structure of the cuckoo filter includes a bucket array, a fingerprint f, and candidate bucket functions b1 and b2. The bucket array consists of multiple buckets, each bucket contains several slots, and a slot can store a fingerprint f. Each bucket in the bucket array can store 4 fingerprints. The fingerprint f is the short hash value of the element. The candidate bucket function is used to calculate the two candidate bucket positions corresponding to the element x, where the position i1=b1(x). Calculate the fingerprint f of element x and the two candidate bucket positions i1 and i2, check whether there are empty slots in the buckets corresponding to i1 and i2. If one of the buckets has an empty slot, store the fingerprint f in the empty slot and the insertion is successful. If both buckets are full, randomly select a fingerprint from one bucket and kick it out. The fingerprint of the kicked element is then tried to be inserted into another possible position i2. Repeat this process until the insertion is successful or the maximum number of attempts is reached; Calculate the fingerprint f of element x and the two candidate bucket positions i1 and i2, check whether the slots in the buckets corresponding to i1 and i2 contain fingerprint f. If the slot of one of the buckets contains f, it is considered that element x may exist in the filter; if all slots of the two buckets do not contain fingerprint f, it is determined that element x does not exist in the filter.

4. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 1 is characterized in that: The directed routing layer is responsible for sending the revoked user credential identifier ID cred Mapped to the corresponding RSA accumulator number, the consistent hashing algorithm is used as the method for routing RSA accumulator selection. The consistent hashing algorithm mapping design process is as follows: 1) Consistent hash ring initialization (a) Define the hash space: Select SHA-256 as the hash function, and the hash space range is [0,2 256 -1], forming a logical closed loop space; (b) Deploy virtual nodes: Each RSA accumulator corresponds to V virtual nodes vnode, and the virtual node hash value H vnode The calculation formula is: H vnode =H(Acc id +Replica id ) Among them, Replica id Is the virtual node replica serial number, the value range is [0, V-1], Acc id is the number of the accumulator; (c) Build a hash ring: H is the hash value of all virtual nodes vnode Sorting to form a consistent hash ring, each virtual node is responsible for the corresponding interval, where is the hash value of the virtual node itself, is the hash value of the next virtual node after sorting; 2) Mapping rule design (a) Locating the virtual node: Calculating the identifier of the credential to be revoked cred The hash value H cred , get the ID cred The position in the consistent hash ring, starting from this position along the consistent hash ring clockwise search, find the first hash value greater than H cred Virtual node vnode m , vnode m satisfy: (b) Mapping RSA accumulator: Locating to virtual node vnode m The physical node corresponding to the virtual node is the target RSA accumulator. The physical node represented by an RSA accumulator corresponds to multiple virtual nodes. By increasing the number of virtual nodes, the virtual nodes are evenly distributed on the consistent hash ring, so that the credential identifier ID to be revoked cred More evenly distributed across the RSA accumulators.

5. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 1 is characterized in that: The precise judgment layer is responsible for storing the identifier ID of the revoked user credentials cred , processing the verification request of the revoked user credentials, the precise judgment layer contains a set of k RSA accumulators {Acc1,Acc2,…,Acc k }, initialized with uniform parameters (p, q, N, g), with the same initial accumulator value Acc0, where p and q are large prime numbers, N = pq, g is the generator, and the i-th RSA accumulator contains a number n i A collection of elements Each element corresponds to the identifier ID of a revoked user credential cred , the accumulated value of the i-th RSA accumulator is expressed as: When the RSA accumulator Acc i When changes occur due to adding or deleting elements, it also exists in the RSA accumulator Acc i Elements No need to renew membership certificate immediately Instead, regenerate the latest membership certificate when applying for verification Where j represents the j-th element in the RSA accumulator i; z represents the numbers of all elements in the RSA accumulator i except the j-th element.

6. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 5 is characterized in that: The precise judgment layer also includes dynamically adjusting the number of RSA accumulators and transferring and revoking user credentials through dynamic expansion and load balancing algorithms, specifically: When the number of revoked certificates stored in any RSA accumulator exceeds the maximum load threshold Load max , trigger the operation of adding a new RSA accumulator, add a new RSA accumulator with the same initialization parameters, generate the corresponding virtual node and insert it into the consistent hash ring, start from the position of the new RSA accumulator on the hash ring, find the next RSA accumulator in the clockwise direction, and migrate the revocation certificates between the two RSA accumulators to the new RSA accumulator; When the number of revoked certificates stored in any RSA accumulator is lower than the minimum load threshold min , triggering the operation of reducing the RSA accumulator, removing all virtual nodes of the RSA accumulator from the consistent hash ring, and then finding all the credentials originally mapped to the RSA accumulator, recalculating the hash values ​​of these credentials, and mapping them to the new RSA accumulator.

7. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 1 is characterized in that: The trusted storage layer is responsible for storing the latest accumulated value Acc of each RSA accumulator in the accurate judgment layer i 、Acc i , the verifier in the trust domain X automatically uploads it to the blockchain network maintained by each node in the trust domain X in the form of a transaction through a smart contract.

8. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 1 is characterized in that: If the identity credential revocation trigger condition is active credential revocation, the specific steps for revoking the 6G heterogeneous network identity credential are as follows: User A initiates a credential revocation request to the verifier in the same trust domain X. The request contains the user's identifier and credential ID. cred , encrypted with the verifier’s public key; After receiving the active credential revocation request from user A, the verifier uses the private key to verify the legitimacy of the request; The verifier parses the user's identity and credential information from the request and verifies the user's legitimacy in the blockchain within the local domain; After the user A's active credential revocation request, identity information and credential information are verified, the verifier will send the user A's credential identifier ID cred Send to the cuckoo filter of the fast pre-filtration layer; Cuckoo filter performs insert element operation and calculates the credential identifier ID cred The fingerprint and candidate bucket position are inserted into the corresponding slot; Further, the credential identifier ID cred Send it to the directional routing layer, where the target RSA accumulator number is calculated using the consistent hashing algorithm; According to the calculated target RSA accumulator number, the credential identifier ID cred Send to the accurate judgment layer; In the precise judgment layer, the RSA accumulator performs the element insertion operation to generate the latest accumulated value; The blockchain node in the trusted storage layer writes the latest accumulated value of the RSA accumulator to the blockchain network in the form of a smart contract transaction, completing the certificate revocation operation for user A; The blockchain node returns the certificate revocation result to user A's client.

9. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 1 is characterized in that: If the identity credential revocation trigger condition is passive credential revocation, the specific steps for revoking the 6G heterogeneous network identity credential are as follows: After user B in trust domain X commits a malicious act, the trust management committee member from trust domain X checks whether user B's comprehensive trust value is lower than the minimum trust threshold of trust domain X, and requests the trust management blockchain node to query and calculate user B's comprehensive trust value; The trust management blockchain node calculates the comprehensive trust value based on the user B's identity identifier and the trust domain X identifier through the node trust evaluation scheme; The trust management blockchain node sends the comprehensive trust value of user B to the members of the trust management committee; The Trust Management Committee members determine whether user B's credentials need to be revoked based on the returned comprehensive trust value; If the judgment result is that the credentials of user B need to be passively revoked, the credential identifier ID of user B will be cred Send to the cuckoo filter of the rapid pre-filtration layer; Cuckoo filter performs insert element operation and calculates the credential identifier ID cred The fingerprint and candidate bucket position are inserted into the corresponding slot; Further, the credential identifier ID cred Send to the directional routing layer to avoid misjudgment of revoked credential verification; The target RSA accumulator number is calculated by consistent hashing algorithm in the directional routing layer; According to the calculated target RSA accumulator number, the credential identifier ID cred Send to the accurate judgment layer; In the precise judgment layer, the RSA accumulator performs the element insertion operation to generate the latest accumulated value; The blockchain node in the trusted storage layer writes the latest accumulated value of the RSA accumulator to the blockchain network in the form of a smart contract transaction, completing the certificate revocation operation for user B; The blockchain node returns the certificate revocation result to user B's client.

10. The blockchain identity certificate revocation method in a 6G heterogeneous network scenario according to claim 1 is characterized in that: The specific steps for verifying whether the user identity certificate has been revoked are: The verifier first performs a quick verification operation, calling the query element interface of the Cuckoo filter; The Cuckoo filter performs the query element operation, and the input parameter is the credential identifier ID to be verified cred The output query result is whether the credential identifier ID exists or not cred ; If the verification result received by the verifier is the credential identifier ID cred If it does not exist, the verification process ends and the result of the credential to be verified has not been revoked is obtained; if the verification result received is the credential identifier ID cred If it exists, continue to execute the subsequent steps; The verifier sends a request for accurate verification to the blockchain node in the local domain, and the request contains the credential identifier ID cred , and encrypted with the validator's private key; The blockchain node verifies the legitimacy of the request through the validator's public key, and then calculates the ID of the target RSA accumulator through the consistent hashing algorithm. acc ; The blockchain node queries the latest accumulated value Acc of the accumulator through the target RSA accumulator number. i , generate the latest membership proof ω, and send the latest accumulated value and membership proof to the verifier; The verifier verifies the validity of the latest member certificate ω through the verification parameters returned by the blockchain node, and finally completes the entire process of verifying whether the user credentials have been revoked.

Images