A blockchain node identity privacy scheme based on edge computing

Abstract

The application provides an edge-computing-based blockchain node identity privacy scheme. The blockchain has the characteristics of high security, high transparency, high autonomy and non-tamperability, and has wide application prospects in the Internet of Things, finance, trade and other industries. However, due to the characteristics of decentralization, a more targeted security scheme is needed to protect user privacy, and the existing signature protection scheme has a large number of complex operations, which brings a large computing burden to the wireless terminal node. In combination with the advantages of edge computing and identity threshold short signature, the application provides an edge-computing-based blockchain node identity weighted threshold short signature scheme to ensure the identity privacy information of the blockchain node and resist collusion attacks.

Description

Technical Field

[0001] This invention primarily relates to the protection of identity privacy in blockchain nodes, proposing a mobile blockchain node network based on edge computing, and on this basis, an efficient identity-based weighted threshold short signature scheme. This scheme utilizes the computing power of edge computing nodes to effectively offload the complex computations required by the blockchain terminal, ensuring the identity privacy of blockchain nodes while reducing the computational burden on the wireless terminal. Background Technology

[0002] Blockchain uses digital digests to verify data, enabling data sharing and interaction across different nodes and platforms. Essentially, it's a distributed ledger technology involving multiple nodes, characterized by data immutability and trustlessness. The continuous advancement of blockchain technology has led to its widespread application across various industries, such as the Internet of Things, banking transactions, and government departments, where blockchain ensures the reliability and security of data and transactions.

[0003] As research deepens, the inherent security issues of blockchain have attracted widespread attention. To ensure the traceability and verifiability of blockchain data, there is no centralized organization to process and maintain the data; all transactions are publicly accessible to all nodes in the blockchain network, leading to data privacy breaches. Attackers can obtain transaction data by attacking only some nodes in the network or by impersonating legitimate nodes. Due to the immutable nature of blockchain, users cannot remedy the situation by altering or deleting data recorded on the chain when personal privacy data is accidentally leaked. Therefore, appropriate privacy protection strategies must be implemented for users beforehand. Encryption is one of the most commonly used solutions in the field of privacy protection, and encryption technology can provide a good solution to the privacy issues of blockchain and ensure the security of user information.

[0004] In recent years, numerous solutions have been proposed to address the privacy needs of blockchain technology. These solutions can be broadly categorized into two types: those based on coin mixing mechanisms and those based on cryptographic algorithms. Among these, cryptographic-based solutions have garnered significant attention due to their superior anonymity. However, existing solutions involve numerous calculations involving elliptic curve point addition, large number exponentiation, and even bilinear mapping. These complex operations are incompatible with the computing power of wireless terminals, and the efficiency of signature transmission and storage in existing solutions is also unsuitable for bandwidth-constrained environments. Summary of the Invention

[0005] To address the identity privacy and security issues of blockchain nodes, this paper proposes a weighted threshold short signature scheme for blockchain node identity based on edge computing. This scheme ensures the identity privacy of blockchain nodes, resists collusion attacks, and reduces the computational burden on wireless terminals.

[0006] This invention proposes a blockchain node identity privacy scheme based on edge computing, comprising two parts: building a mobile blockchain network based on edge computing and an identity-based weighted threshold short signature scheme.

[0007] To address the challenges of resource storage, computing performance, energy efficiency, and resource allocation in blockchain networks, this invention employs a mobile edge computing network model. This model migrates context-sensitive, latency-sensitive, and computationally intensive tasks from user workloads to nearby edge computing nodes for processing. Proximity to the user provides IT services, environment, and cloud computing capabilities to meet the demands of low-latency, high-bandwidth business applications. The model divides nodes into a cloud service layer, a blockchain layer, and an edge computing layer. The cloud service layer combines traditional cloud storage with blockchain technology to ensure data security. The blockchain layer ensures data security during blockchain transmission, provides integrity and anti-counterfeiting credentials for the edge computing system, and ensures the fairness and effectiveness of storage resources allocated to edge devices. The edge computing layer provides computing resources and edge cloud services to the blockchain layer. This model combines cloud computing, edge computing, and blockchain, leveraging the powerful computational offloading capabilities of edge computing to improve the computational efficiency of blockchain node signatures.

[0008] To protect the identity privacy of blockchain nodes, an identity-based weighted threshold short signature scheme is adopted. Digital signatures play a crucial role in public-key cryptography. In traditional public-key cryptography, the legitimacy of a user's public key is guaranteed by the legitimacy of the public key certificate. The legitimacy of the public key certificate depends on the authority of the CA and the legitimacy of the CA's signature. To simplify public key management, an identity-based cryptography scheme is adopted. Short signatures can improve the efficiency of signature transmission and storage, especially suitable for bandwidth-constrained environments. This invention implements an identity-based weighted threshold short signature scheme through five processes: system initialization, node joining, key distribution, signing, and signature verification.

[0009] This invention utilizes edge computing nodes to effectively offload the computational complexity of blockchain terminals, ensuring the privacy of blockchain node identities while reducing the computational burden on wireless terminals. Attached Figure Description

[0010] Figure 1 Mobile blockchain node network based on edge computing Detailed Implementation

[0011] Mobile blockchain network based on edge computing

[0012] Mobile Edge Computing (MEC), as a novel network model, alleviates the pressure on remote cloud servers and reduces network latency by migrating context-sensitive, latency-sensitive, and computationally intensive tasks in mobile user operations to nearby edge computing nodes. These edge nodes, equipped with computing and storage resources, are typically deployed in devices close to users, such as gateways, Wi-Fi nodes, macro base stations, and cell base stations. This paper, based on the network architecture of edge computing, assigns blockchain attributes to MEC servers as consensus nodes, enabling smart terminals to connect to the blockchain via the MEC servers.

[0013] As attached Figure 1 The blockchain layer includes MEC servers, which are endowed with blockchain attributes to act as consensus nodes, and mobile devices, in-vehicle mobile network devices, or IoT devices connected to the blockchain via these servers. The edge computing layer includes a local key distribution center, a local trusted management center, and MEC servers. The MEC servers provide computing resources to the blockchain layer and distribute security policies. The cloud service layer includes a cloud service center and cloud servers, providing cloud services to the edge computing layer and distributing security policies. The blockchain layer ensures the security of data transmitted through the blockchain, helps establish integrity guarantees and anti-counterfeiting evidence for the edge computing system, and ensures that the storage resources allocated on edge devices are fair and effective, making it scalable. The edge computing layer provides computing resources and edge cloud services to the blockchain layer, while the cloud service layer combines traditional cloud storage with the use of blockchain to ensure data security.

[0014] Blockchain identity privacy solutions

[0015] This scheme is a signature algorithm, and the system parameters are: First, the symbols used in this scheme are defined and explained:

[0016] k: Security parameter, which determines the size of the numerical space of the computation defined in the encryption mechanism of this scheme. The larger the security parameter, the more difficult it is to crack this signature scheme, that is, the higher the security of the scheme.

[0017] q: A value > 2 k Large prime numbers.

[0018] A multiplicative cyclic group of order q.

[0019] A multiplicative cyclic group of order q.

[0020] P: Group The generator of a group is the product of the minimum number of group elements, where P is the group of elements.

[0021] e: Bilinear mapping, a mapping relationship defined on two groups, which is bilinear, nondegenerate, and computable.

[0022] Z q : The q-order prime field.

[0023] Cyclic group of integer multiplication.

[0024] {0, 1} * : Refers to a 0 or 1 bit string of arbitrary length.

[0025] H1: Map a bit string of arbitrary length to a

[0026] H2: Combine bit strings and groups of arbitrary length The element-wise dot product in the matrix is ​​mapped to a single element.

[0027] s: System master key.

[0028] P pub : System public key.

[0029] N0: A terminal node in the blockchain.

[0030] Additional explanation: In the subsequent specific scheme, multiple sets of random numbers will be selected, which will not be explained here. The randomness of these parameters and the existence of mathematical difficulties make the cryptographic scheme secure and unbreakable.

[0031] 1. System Initialization

[0032] Given a security parameter k, the PKG (Private Key Generation) selects two prime numbers q > 2. k group and A modified Weil for e: PKG selects random numbers As the system master key, calculate the system public key. PKG Releases System Parameters Secretly kept.

[0033] 2. Adding a node

[0034] Let the private key and public key of blockchain terminal N0 be (x0, y0 = x0P). Blockchain terminal N0 joins the local edge computing network according to the following steps.

[0035] Step 1: Blockchain terminal N0 sends its identity identifier ID0, public key y0, and connection request information Req to PKG to request to join the edge computing network.

[0036] Step 2: After receiving the connection request information Req, PKG sends its identity identifier ID to the blockchain terminal N0. K Public key P pub and random number r K .

[0037] Step 3: Blockchain terminal N0 selects random numbers r0 and r′0 to calculate s0 = r K x+r0. Blockchain terminal N0 sends r′0, s0, and r0P to PKG.

[0038] Step 4: After receiving the information, the PKG verifies it.

[0039] s0P=r K y0+r0P

[0040] Complete the authentication of blockchain terminal N0. PKG selects a random number r′. K Calculate s K =r′0γ+r′ K PKG will r′ K s K ,r′ K P sends a message to blockchain terminal N0.

[0041] Step 4: After receiving the information, blockchain terminal N0 verifies it.

[0042] s K P=r0′P pub +r′ K P

[0043] Complete the PKG certification.

[0044] Note

[0045] s0P=(r K x+r0)P=r K y0+r0P

[0046] The correctness of the above scheme is obvious, and its security analysis can be proven by traditional methods. The main proof process is omitted in this specification.

[0047] 3. Key Distribution

[0048] Suppose a local trusted management center manages several MEC servers. A certain MEC server is a wireless terminal N1,...,N m Provides uninstallation service. Uninstallation requires N1,...,Nm Several nodes work together to complete a (t,m) threshold signature, where m is the number of nodes and t is the signature threshold. Only when at least t share signatures are collected can a valid signature be synthesized.

[0049] Given the identity of the user who needs to sign, GID∈{0,1} * PKG calculates its public key Q. GID =H1(GID), which means substituting the GID bit string into H1, and using the mapping result as its public key and private key. To distribute the key value required for signing, the PKG chooses to define it in Z. q The Lagrange polynomial f(x) on:

[0050]

[0051] PKG transmits the key fragment value d through a secure channel. ID =f(ID) is the node whose identity is ID that participated in the threshold signature.

[0052] 4. Signature

[0053] If the wireless terminal nodes served by the MEC server need to sign a given message M∈{0,1}*, the following process applies.

[0054] 1) Nodes N1,...,N m Select random numbers r1,...,r respectively m m is the number of nodes, and it is used for group broadcasting and sending to the MEC server.

[0055] 2) The MEC server receives r1,...,r m Then, the system public key and the node public key are used to calculate...

[0056]

[0057] U = r(P) pub +Q GID P)

[0058] It then broadcasts U, where U is the intermediate value that must be obtained using the system public key and the user public key during the signature calculation process.

[0059] 3) Nodes N1,...,N m Calculate separately

[0060]

[0061] h = H2(M,U)

[0062] M is to be the bit string and U is to be the group. Substituting the elements in H2 into H2, the resulting h is an intermediate value obtained during the signature calculation process.

[0063] Then select random numbers r′1,...,r′ m Calculate their respective share signatures (s i ,z i ):

[0064]

[0065] Where λ i Let d be the Lagrange multiplier. i These are the key fragments received by each node previously.

[0066] Each wireless terminal node N1,...,N m After completing the share signing, send to MEC respectively

[0067] s1,z1,...,s m ,z m

[0068] 4) After MEC receives at least t share signatures, it calculates...

[0069]

[0070] Output (s, z) as the signature of message M.

[0071] 5. Signature verification

[0072] Given a message / signature pair (M,s,z), the verifier is calculated as follows:

[0073] i. Calculate h = H2(M,U);

[0074] ii. The verifier chooses to believe the signature (s,z) and outputs a verification value of 1 if and only if the following expression is true:

[0075]

[0076] Where Ver represents the verification process, and e(P,P) is... Given generators P and bilinear mappings of P, we will now verify the correctness of the equation.

[0077] prove

[0078]

Claims

1. A blockchain node identity privacy method based on edge computing, characterized in that: It includes two parts: building a mobile blockchain network based on edge computing and identity-based weighted threshold short signatures; Specifically as follows: Mobile blockchain network based on edge computing Based on the network architecture of edge computing, the mobile edge computing (MEC) server is given blockchain attributes to serve as a consensus node, and smart terminals are connected to the blockchain through the MEC server. The blockchain layer includes MEC servers, which are endowed with blockchain attributes to act as consensus nodes, as well as mobile devices, vehicle-mounted mobile network devices, or IoT devices that are connected to the blockchain via the servers; the edge computing layer includes a local key distribution center, a local trusted management center, and MEC servers, which provide computing resources to the blockchain layer and distribute security policies; the cloud service layer includes a cloud service center and cloud servers, which provide cloud services to the edge computing layer and distribute security policies. Identity-based weighted threshold short signatures: This method is a signature algorithm, and the system parameters are: First, the symbols used in this method are defined and explained: k: Security parameter. The larger the security parameter, the more difficult it is to crack this signature scheme, that is, the higher the security of the scheme. A numerical value Large prime numbers; A class of Multiplication cyclic group; A class of Multiplication cyclic group; :group The generators of a group are the elements generated by the product of the minimum number of group elements, and P is the group of group elements. Bilinear mapping is a mapping relationship defined on two groups, which has the properties of bilinearity, nondegeneracy, and computability. : prime number field; : Integer multiplication cyclic group; : Refers to a 0 or 1 bit string of arbitrary length; Mapping a bit string of arbitrary length to a... ; : Combine bit strings and groups of arbitrary length The element-wise dot product in the matrix is ​​mapped to a single element. ; S1: System Master Key; System public key; A terminal node in a blockchain; 1) System Initialization Given a security parameter k, the PKG private key generation center selects two numbers whose order is both prime. group and A modified Weil pair PKG selects random number S1 As the system master key, calculate the system public key. S1 PKG releases system parameters S1 is kept secret; 2) Node addition Set up a blockchain terminal The private key and public key are respectively Blockchain terminal Join the local edge computing network by following these steps; Step 1, Blockchain Terminal Identity Public key Connection request information Send a request to join the edge computing network to the PKG; Step 2: After receiving the connection request information Req, PKG sends it to the blockchain terminal. Send PKG's identity identifier Public key and random numbers ; Step 3, Blockchain Terminal Select random numbers ,calculate Blockchain terminal Will Send PKG; Step 4: After receiving the information, the PKG verifies it. ； Complete the blockchain terminal Authentication; PKG selects random numbers ,calculate PKG will Send blockchain terminal ; Step 5, Blockchain Terminal After receiving the information, verify. ； Complete the PKG certification; 3) Key distribution Set up a local trusted management center to manage several MEC servers; A certain MEC server is a wireless terminal Provide uninstallation service; Uninstallation requires Several nodes work together to complete Threshold signature, where m is the number of nodes and t is the threshold value for the signature. Only when at least t share signatures are collected can a valid signature be synthesized. Given the identity of the user who needs to sign PKG calculates its public key Soon Bit string substitution The mapping result is used as its public key and private key. To distribute the key value required for signing, the PKG chooses to define it in Lagrange polynomials on : ； PKG transmits the key fragments through a secure channel. The node whose identity is ID is assigned to participate in the threshold signature; 4) Signature If the wireless terminal node served by the MEC server needs to process a given message The signing process is as follows; a) Node Select random numbers r1, ..., r respectively. m m is the number of nodes, and it is broadcast within the group and sent to the MEC server; b) The MEC server receives r1, ..., r m Then, the system public key and the node public key are used to calculate... ； ； And broadcast ,in This is the intermediate value that must be obtained using the system public key and the user public key during the signature calculation process; c) Node Calculate separately ； Soon As a bit string As a group Substitution of elements The generated h is an intermediate value obtained during the signature calculation process; Then select a random number. Calculate their respective share signatures : ； in For Lagrange coefficients, These are the key fragments received by each node previously; Each wireless terminal node After completing the share signing, send to MEC respectively ； d) After MEC receives at least t share signatures, it calculates... ； Output As a message The signature; 5) Signature verification Given message / signature pair The verifier calculates as follows: i. Calculation ; ii. The verifier chooses to believe the signature if and only if the following expression is true. And output a checksum of 1: ； Where Ver represents the verification process. for Generator and A bilinear mapping.

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