Lightweight security identity verification method based on hybrid authentication architecture

Abstract

The invention discloses a lightweight security identity authentication method based on a hybrid authentication architecture, which comprises the following steps of: centralizing edge-level authentication, and registering an Internet of Things system; communicating the equipment of the Internet of Things system with the edge server; whether the two devices needing to communicate are connected to the same edge server or not is judged, and if yes, the two devices conduct same-domain communication; and if not, the two devices carry out cross-domain communication. By combining centralized and decentralized authentication architectures, the security, expandability and real-time performance of an Internet of Things system are effectively improved, and the problems of calculation, storage, delay and the like in a traditional authentication method are solved while the performance of resource-constrained equipment is guaranteed.

Description

Technical Field

[0001] The present invention relates to the field of the Internet of Things, and particularly to a lightweight secure authentication method based on a hybrid authentication architecture. Background Art

[0002] The Internet of Things (IoT) is gradually evolving into a ubiquitous technology aimed at significantly improving and enriching human life with minimal time and effort investment. With the expansion of IoT applications, especially in areas such as smart homes, smart cities, and industrial automation, the popularity of IoT devices has enabled a large number of physical devices, sensors, and smart terminals to be interconnected. However, resource-constrained IoT devices face significant security threats, especially the risk of physical-layer intrusion.

[0003] Since IoT devices typically have low computing power, limited storage space, and finite battery life, traditional security solutions, especially cryptographic primitives (such as RSA, AES, and SHA), consume a large amount of resources during processing, which is not practical for resource-constrained IoT devices. At the same time, in IoT networks, device authentication often requires frequent information exchange, resulting in high bandwidth consumption. In addition, due to IoT devices being deployed in different environments and networks, the authentication and interoperability requirements between heterogeneous systems make it difficult for traditional authentication protocols to meet real-time requirements and also fail to effectively handle potential delays during protocol execution. Therefore, the industry has begun to re-examine the design concept of IoT protocols and seek lightweight, secure, and efficient authentication methods.

[0004] Existing centralized authentication schemes perform poorly in cross-domain authentication and cannot meet the scalability requirements of large-scale IoT systems. To overcome these problems, blockchain technology has gradually been introduced into the IoT field, especially for establishing a decentralized authentication mechanism between devices. However, most blockchain-based authentication methods still have relatively large overheads in terms of computing, storage, and energy consumption. Especially in real-time IoT systems, the additional delays caused by authentication time and consensus mechanisms pose an important challenge. With the increase in IoT devices and data volume, the computing bottlenecks of traditional centralized authentication methods and public blockchains make the authentication process even more inefficient. Summary of the Invention

[0005] To solve the above technical problems, the present invention provides a lightweight secure authentication method based on a hybrid authentication architecture with a simple algorithm, high security, and reliability.

[0006] The technical solution of the present invention to solve the above technical problems is: a lightweight secure authentication method based on a hybrid authentication architecture, comprising the following steps: S1: Centralized edge-level authentication to register the IoT system; The specific process of step S1 is as follows: S11: Assign a unique identifier EID to each edge server, and generate a public key and a private key for each edge server; S12: Use the system name S B and the hash of the corresponding edge server to generate a unique group identifier GID for the Internet of Things system, and register the new Internet of Things system to the nearest edge server; S13: Generate a unique object identifier OID to identify each object O in group G. In addition, the edge server generates a random input stimulus, i.e., a challenge C, for the physically unclonable function PUF, and collects the generated response R; then, store the challenge-response pair (C, R) in the secure database; R is collected and stored in the secure database of the edge server, and for each device, only one challenge-response pair is stored during the registration phase; S2: Communicate the devices of the Internet of Things system with the edge server; The specific process of step S2 is as follows: S21: Initialize the connection between the device and the edge server; First, the device Node B sends a connection request message to the edge server. The connection request message contains the unique identifier OID of Node B ; after receiving the request, the edge server looks up the challenge-response pair (C B , R B ) corresponding to Node B from the secure database. C B represents the challenge of Node B , and R B represents the response corresponding to the found C B ; then, the edge server generates a random number RN1, and performs an exclusive OR (XOR) operation on RN1 and R B to obtain the encrypted message D B ; next, the edge server calculates the hash value H B of the message D B and R B to ensure the integrity of the information; finally, the edge server sends the message D B , H B , and C B back to Node B ; the formula is as follows: ; ; ; where, represents the exclusive OR operation, represents the concatenation symbol, denotes a hash function; S22: The device authenticates the edge server; S23: The edge server authenticates the device; S3: Determine whether two devices that need to communicate are connected to the same edge server. If so, proceed to step S4; if not, proceed to step S5; S4: The two devices perform in-domain communication; The specific process of the said step S4 is as follows: S41: Initialize the connection between two in-domain devices; The two in-domain devices are device Node A1 and device Node A2 , device Node A1 sends a connection request message to the edge server. The connection request message contains the unique identifier OID A1 of Node A1 and the unique identifier OID A2 of Node A2 ; after receiving the connection request, the edge server checks whether Node A2 is registered through the database and sends a connection request to Node A2 . After receiving the connection request, Node A2 selects a flag and sends an N2N connection establishment request (OID A1 , OID A2 ) to the edge server; after receiving the N2N connection establishment request, the edge server obtains the corresponding challenge-response pair (C A1 , R A1 , C A2 , R A2 ) from the security database and generates a random number RN2. C A1 represents the challenge of Node A1 , R A1 represents the response corresponding to C A1 , C A2 represents the challenge of Node A2 , R A2 represents the response corresponding to C A2 ; perform XOR operations on the random number RN2 with R A1 and R A2 respectively to obtain the encrypted messages D A1 and D A2 , and the formula is as follows: ; ; Then, calculate R A1With D A1 The hash value H A1 of R A2 and D A2 The hash value H A2 To verify the transmitted message; the edge server sends the data D A1 H A1 and C A1 Back to Node A1 Send the data D A2 H A2 and C A2 Back to Node A2 ; The formula is as follows: ; ; S42: Two devices in the same domain authenticate the edge server; S43: The edge server authenticates two devices in the same domain; S5: Two devices perform cross - domain communication; The specific process of step S5 is as follows: S51: The two cross - domain devices are device Node A3 and device Node A4 respectively. Device Node A3 first sends an association request to the edge server E3 it is connected to; through step S22 and step S23 for identity authentication and key exchange, after successful device authentication, E3 sends a transaction to the blockchain Bch by providing the unique identifier OID A4 of device Node A4 and the edge server E4 connected to Node A4 ; S52: Bch verifies whether the given OID A4 and the corresponding unique identifier exist on the blockchain; if the verification passes, the process continues; otherwise, the process terminates and returns an error; S53: When the verification that the other device exists is successful, Bch creates a block to store the mapping information of device Node A3 and Node A4 ; S54: Device Node A3 performs identity authentication and key exchange with the edge server E3 it is connected to through step S22 and step S23. After successful device authentication, a session key Key A3 is generated between the edge server E3 and device Node A3 , and the edge server E3 uses the public key Pk4 of the target edge server for the edge server E3 and device Node A3The key Key A3 Encrypt to obtain the encrypted data packet M k , and then send the encrypted data packet M k to the edge server E4; S55: When the edge server E4 receives M k , create a new transaction block F and share it with the blockchain-based edge network, and at the same time send a connection establishment request to Node A4 , Node A4 After receiving the request, perform identity authentication and key exchange with the edge server E4 connected to it through steps S22 and S23. If the edge server E4 and the device Node A4 successfully authenticate each other, then a communication key Key A4 is generated between the edge server E4 and the device Node A4 , otherwise, an error will be reported and the process will end; S56: Next, the edge server E4 verifies the validity of the block to ensure the legality of the block transaction; S57: Once the block passes the verification, the edge server E4 will use its private key Prk4 to decrypt Key k from M A3 ; Encrypt Key A3 with Key A4 to obtain the data M SK , and send M SK to the device Node A4 , and the device Node A4 After receiving M SK , decrypt it with Key A4 to obtain Key A3 , thus completing cross-region identity authentication and key exchange.

[0007] In the above lightweight security authentication method based on a hybrid authentication architecture, in step S11, the trusted institution TA first sets a finite field parameter, that is, selects a prime number p to construct the finite field Fp. On the finite field Fp, an elliptic curve Eq(m,n) is defined, and its expression is as follows: Eq(m,n):y 2 =x 3 +mx + n; Where: x, y ∈ Fp, where x and y respectively represent the abscissa and ordinate of a point on the elliptic curve; m, n are coefficient parameters of the elliptic curve, and m, n ∈ Fp; after constructing the elliptic curve, calculate the point set G of the elliptic curve over the finite field Fp, and the point set G forms a finite additive group under the elliptic curve addition rule; subsequently, TA selects a base point g from the additive group, where g ∈ G; the order of the base point g is q, and to ensure the non-singularity of the elliptic curve, it is required to satisfy the condition: 4m 3 + 27n 2 mod q ≠ 0, where mod represents the modulo operation; TA randomly selects a private key Prk in the integer set Zq = {0, 1, 2,..., q - 1}, where Prk ∈ [1, q - 1], and Prk is an integer satisfying 1 ≤ Prk < q; then, calculate the corresponding public key: Pk = Prk·g, where · represents the scalar multiplication operation, Pk is the public key corresponding to the private key Prk, and Pk ∈ G; finally, TA publishes the following public parameters to all edge servers participating in the identity verification: {Eq(m, n), g, q, Pk}, and at the same time, the private key Prk is only sent to and held in confidence by the corresponding server and not made public to the outside to ensure the security of the entire identity authentication process.

[0008] For the lightweight security authentication method based on the hybrid authentication architecture, the specific process of step S22 is as follows: Node B After receiving the message from the edge server, first use the embedded PUF instance to generate , which is the response obtained according to C B ; then, Node B calculates the hash value of B and D and compares with the received H B to verify the integrity of the message; if the two are consistent, it means the message has not been tampered with during transmission, then Node B confirms the integrity of the message, proving that it is a legitimate request from the edge server; Node B performs an exclusive OR decryption on the received message D B and to extract the random number RN1 and generate the key Key1; Once Node B completes the authentication of the edge server, Node B generates a new challenge C B+1 and the corresponding response R B+1 through the PUF, where C B+1 is C B and R BThe XOR value; then, take R B+1 and XOR it with RN1 to generate message D B+1 , and calculate the value of which is H B+1 , then send D B+1 and H B+1 to the edge server; the formula is as follows: ; ; ; ; ; ; ; ; where, represents the physical unclonable function of Node B , represents judging whether they are equal.

[0009] For the above lightweight security authentication method based on the hybrid authentication architecture, the specific process of step S23 is as follows: Assume that the edge server receives H B+1 and message , is the received message corresponding to D B+1 . First, decrypt using the random number RN1 to recover the updated response B of Node . Next, calculate and the hash value of ; verify the correctness of the device response by comparing with the received H B+1 ; if the hash verification is successful, it means that the authentication of device Node B has been successful, and the edge server updates the challenge C B+1 and response R B+1 in the manner of a legitimate node and stores them in the secure database; once Node B successfully passes the edge server authentication, the edge server and Node B use as the session key for secure communication; the formula is as follows: ; ; ; Next, the authentication information is recorded in the edge server as a transaction in the edge blockchain network BCH; Finally, the edge server updates the stored challenge to C B+1 , and replaces the old challenge-response pair data with the new data in the manner of a legitimate node, and stores it in the secure database; the formula is as follows: .

[0010] For the lightweight security authentication method based on the hybrid authentication architecture, the specific process of step S42 is as follows: Node A1 After receiving the message from the edge server, it will first use its embedded PUF instance to generate , where is the response obtained according to the challenge C A1 of Node A1 ; then, Node A1 uses the generated to compare with the hash A1 of D and the received H A1 to verify the integrity of the message; the formula is as follows: ; ; represents the physical unclonable function of Node A1 ; If is consistent with H A1 , it means that the message has not been tampered with during transmission. Node A1 confirms the integrity of the message and proves that it is a legitimate request from the edge server; Node A1 performs an exclusive OR decryption on the received message D A1 and to extract the random number RN2 and generate the key Key2; once Node A1 completes the authentication of the edge server, Node A1 will update its PUF response. Node A1 generates a new challenge C A1+1 and the corresponding response R A1+1 through the PUF, and sends C A1+1 and R A1+1 back to the server, where C A1+1 is the exclusive OR value of C A1 and R A1 ​A1+1 is the response obtained by challenging C A1+1 ; Next, XOR R A1+1 with RN2 to generate the string D A1+1 and calculate the hash value of R A1+1 and D A1+1 which is H A1+1 The formula is as follows: ; ; ; ; ; ; Similarly, Node A2 authenticates the server in the same way after receiving the message. The formula for Node A2 node authentication is as follows: ; ; ; ; ; ; ; ; where, represents the physical unclonable function of Node A2 , is the challenge for Node A2 , is the response obtained according to , is and the hash value of D A2 , is the new challenge generated by Node A2 through PUF, is the corresponding response, is and the string generated by XOR, is and the hash value; Node A1 sends the message {D A1+1 , HA1+1} is sent to the edge server, Node A2 Send the message {D A2+1 and H A2+1} to the edge server.

[0011] For the lightweight security authentication method based on the hybrid authentication architecture described above, the specific process of step S43 is as follows: The server receives the messages {D A1+1 and H A1+1} and the messages {D A2+1 and H A2+1}. First, by performing an exclusive OR operation on D A1+1 and D A2+1 with the corresponding previously generated random number RN2, the updated PUF responses of Node A1 and the updated PUF response of Node and Node A2 are restored; subsequently, the edge server calculates the hash value of and D A1+1 , , the hash value of A2+1 and D to check the integrity of the messages; after the hash value verification is completed, the edge server successfully authenticates two Internet of Things devices, namely Node A1 and Node A2 ; the formulas are as follows: ; ; ; ; ; Next, the edge server updates the stored challenges C A1 and C A2 to C A1+1 and C A2+1 , and replaces the old challenge-response pair data with the new data in the manner of a legitimate node, , , , , , and stores them in the secure database; the formulas are as follows: ; ; Once Node A1 and Node A2Successfully authenticated by the edge server, Node A1 、Node A2 and the edge server use Key2 as the session key for secure communication; finally, the authentication information is recorded in the edge server and recorded as a transaction in the edge blockchain network BCH.

[0012] The beneficial effects of the present invention are as follows: 1. The present invention proposes a hybrid authentication architecture that combines centralized and blockchain-based authentication methods to serve the security needs of the Internet of Things system. In the hybrid authentication architecture, by deploying edge servers to provide centralized authentication services for associated Internet of Things devices, the burden on devices directly accessing the blockchain network is reduced; by combining centralized edge servers and blockchain networks, a decentralized authentication and verification mechanism is constructed, which can realize device authentication across different heterogeneous Internet of Things systems.

[0013] 2. In order to adapt to the resource-constrained Internet of Things environment, the present invention proposes a lightweight authentication and key exchange protocol, which uses low-overhead encryption technologies such as encrypted exclusive OR (XOR) operations and hash functions to achieve secure communication, and uses physical unclonable functions (PUFs) to generate unique device identities to prevent physical attacks. PUF generates a unique identity identifier related to the device through the physical characteristics of the device, has anti-tampering and non-clonable properties, and can effectively prevent traditional key extraction attacks. In addition, PUF does not require key storage, further reducing storage and computing overhead, and is an ideal choice for addressing security and resource limitations in the Internet of Things environment.

[0014] 3. By combining centralized and decentralized authentication architectures, the present invention not only effectively improves the security, scalability and real-time performance of the Internet of Things system, but also solves the problems of computing, storage and latency existing in traditional authentication methods while ensuring the performance of resource-constrained devices. Description of the Drawings

[0015] Figure 1 is the overall flowchart of the present invention. Detailed Embodiments

[0016] The present invention will be further described below with reference to the drawings and embodiments.

[0017] As Figure 1 shown, a lightweight security authentication method based on a hybrid authentication architecture includes the following steps: S1: Centralized edge-level authentication, registering the Internet of Things system.

[0018] The specific process of step S1 is as follows: S11: Assign a unique identifier EID to each edge server, and generate a public key and a private key for each edge server; In the step S11, the trusted authority TA first sets a finite field parameter, that is, selects a prime number p to construct the finite field Fp. On the finite field Fp, an elliptic curve Eq(m,n) is defined, and its expression is as follows: Eq(m,n):y 2 =x 3 +mx+n; where: x, y ∈ Fp, x and y respectively represent the abscissa and ordinate of the points on the elliptic curve; m, n are the coefficient parameters of the elliptic curve, m, n ∈ Fp; after constructing the elliptic curve, calculate the point set G of the elliptic curve on the finite field Fp, and the point set G forms a finite additive group under the elliptic curve addition rule; subsequently, TA selects a base point g from the additive group, g ∈ G; the order of the base point g is q, and to ensure the non-singularity of the elliptic curve, it is required to satisfy the condition: 4m 3 +27n 2 mod q≠0, mod represents the modulo operation; TA randomly selects a private key Prk in the integer set Zq={0,1,2,...,q - 1}, Prk ∈ [1,q - 1], Prk is an integer satisfying 1 ≤ Prk < q; then, calculate the corresponding public key: Pk = Prk·g, where · represents the scalar multiplication operation, Pk is the public key corresponding to the private key Prk, Pk ∈ G; finally, TA publishes the following public parameters to all edge servers participating in the identity authentication: {Eq(m,n), g, q, Pk}, meanwhile, the private key Prk is only sent to and held secretly by the corresponding server and not made public to the outside to ensure the security of the entire identity authentication process.

[0019] S12: Use the system name S name and the hash of the corresponding edge server to generate a unique group identifier GID for the Internet of Things system, and register the new Internet of Things system to the nearest edge server.

[0020] S13: Generate a unique object identifier OID to identify each object O in the group G. In addition, the edge server generates a random input stimulus, that is, a challenge C, for the physically unclonable function PUF, and collects the generated response R; then, store the challenge-response pair (C, R) in the secure database; R is collected and stored in the secure database of the edge server, and for each device, only one challenge-response pair is stored in the registration phase.

[0021] S2: Communicate the devices of the Internet of Things system with the edge server.

[0022] The specific process of the step S2 is as follows: S21: Initialize the connection between the device and the edge server; First, the device NodeB Send a connection request message to the edge server. The connection request message contains the unique identifier OID of the Node B ; After receiving the request, the edge server looks up the corresponding challenge-response pair (C B , R B ) of the Node from the security database. C B represents the challenge of the Node B , and R B represents the corresponding response found for C B ; Then, the edge server generates a random number RN1 and performs an exclusive OR (XOR) operation on RN1 and R B to obtain the encrypted message D B ; Next, the edge server calculates the hash value H B of the message D B and R B to ensure the integrity of the information; Finally, the edge server sends the message D B , H B , and C B back to the Node B ; The formula is as follows: B ; B ; ; ; Among them, represents the XOR operation, represents the concatenation operator, represents the hash function; S22: The device authenticates the edge server.

[0023] The specific process of the step S22 is as follows: After receiving the message from the edge server, the Node B first uses the embedded PUF instance to generate , is the response obtained according to C B ; Then, the Node B calculates the hash value of B and D and compares with the received H B to verify the integrity of the message; If the two are consistent, it means that the message has not been tampered with during transmission, and the Node B confirms the integrity of the message and proves that it is a legitimate request from the edge server; The Node B compares the received message D B with Perform XOR decryption to extract the random number RN1 and generate the key Key1; Once Node B completes the authentication of the edge server, Node B will generate a new challenge C B+1 and the corresponding response R B+1 , where C B+1 is the XOR value of C B and R B ; then, XOR R B+1 with RN1 to generate the message D B+1 , and calculate the value of which is H B+1 , then send D B+1 and H B+1 to the edge server; the formula is as follows: ; ; ; ; ; ; ; ; where, represents the physical unclonable function of Node B , represents judging whether they are equal.

[0024] S23: The edge server authenticates the device.

[0025] The specific process of the step S23 is as follows: Assume that the edge server receives H B+1 and the message , is the message corresponding to the received D B+1 , first use the random number RN1 to decrypt to recover the updated response B of Node , and then calculate the hash value of and ; verify the correctness of the device response by comparing with the received H B+1 ; if the hash verification is successful, it means that the device Node BThe authentication has been successful, and the edge server updates the challenge C as a legitimate node B+1 and the response R B+1 and stores them in the secure database; once Node B successfully passes the authentication of the edge server, the edge server and Node B will use as the session key for secure communication; the formula is as follows: ; ; ; Next, the authentication information is recorded in the edge server and recorded as a transaction in the edge blockchain network BCH; Finally, the edge server updates the stored challenge to C B+1 and replaces the old challenge-response pair data with new data in the manner of a legitimate node, and deposits it in the secure database; the formula is as follows: .

[0026] S3: Determine whether the two devices that need to communicate are connected to the same edge server. If so, go to step S4; if not, go to step S5.

[0027] S4: The two devices perform in-domain communication.

[0028] The specific process of the step S4 is as follows: S41: Initialize the connection between two in-domain devices; The two in-domain devices are device Node A1 and device Node A2 , and device Node A1 sends a connection request message to the edge server. The connection request message contains the unique identifier OID A1 of Node A1 and the unique identifier OID A2 of Node A2 ; after receiving the connection request, the edge server checks whether Node A2 is registered through the database and sends a connection request to Node A2 , and after receiving the connection request, Node A2 selects a flag to send an N2N connection establishment request (OID A1 , OID A2 ) to the edge server; after receiving the N2N connection establishment request, the edge server obtains the corresponding challenge-response pair (C A1 , RA1 , C A2 , R A2 ) and generate a random number RN2, C A1 represents the challenge of Node A1 , R A1 represents the response corresponding to C A1 , C A2 represents the challenge of Node A2 , R A2 represents the response corresponding to C A2 ; The random number RN2 is respectively XOR-operated with R A1 and R A2 to obtain the encrypted messages D A1 and D A2 , and the formula is as follows: ; ; Next, calculate the hash values H A1 of R A1 and D A1 , and the hash values H A2 of R A2 and D A2 to verify the conveyed messages; The edge server sends the data D A1 , H A1 and C A1 back to Node A1 , and sends the data D A2 , H A2 and C A2 back to Node A2 ; The formula is as follows: ; ; S42: Two devices in the same domain authenticate the edge server.

[0029] The specific process of the step S42 is as follows: Node A1 After receiving the message from the edge server, it will first use its embedded PUF instance to generate , is the response obtained according to the challenge C A1 of Node A1 ; Then, Node A1 uses the generated to compare with the hash A1 of D received and H A1 to verify the integrity of the message; The formula is as follows: ; ; represents Node A1 's Physically Unclonable Function; If is consistent with H A1 both, it indicates that the message has not been tampered with during transmission, and Node A1 confirms the integrity of the message, proving it is a legitimate request from the edge server; Node A1 XOR decrypts the received message D A1 with to extract the random number RN2 and generate the key Key2; Once Node A1 completes the authentication of the edge server, Node A1 will update its PUF response, and Node A1 generates a new challenge C A1+1 and the corresponding response R A1+1 , and sends C A1+1 and R A1+1 back to the server, where C A1+1 is the XOR value of C A1 and R A1 , and R A1+1 is the response obtained using the challenge C A1+1 ; Next, XOR R A1+1 with RN2 to generate the string D A1+1 , and calculate the hash value of R A1+1 and D A1+1 which is H A1+1 , and the formula is as follows: ; ; ; ; ; ; Similarly, Node A2 authenticates the server in the same way after receiving the message. The formula for Node A2 node authentication is as follows: ; ; ; ; ; ; ; ; wherein, represents the physical unclonable function of Node A2 ; is the challenge for Node A2 ; is the response obtained according to ; is the hash value of the combination of A2 and D is the new challenge generated by Node A2 through the PUF is the corresponding response is the string generated by XORing with is the hash value of the combination of and Node A1 sends the message {D A1+1 , H A1+1} to the edge server, and Node A2 sends the message {D A2+1 , H A2+1} to the edge server.

[0030] S43: The edge server authenticates two devices in the same domain.

[0031] The specific process of step S43 is as follows: After receiving the message {D A1+1 , H A1+1} and the message {D A2+1 , H A2+1}, the edge server first XORs D A1+1 and D A2+1 with the previously generated random number RN2 to recover the updated PUF response A1 of Node and the updated PUF response A2 of Node ; Subsequently, the edge server calculates the hash value of the combination of , the hash value of the combination of , to check the integrity of the message; after the hash value verification is completed, the edge server successfully authenticates two IoT devices, namely Node A1 and Node A2 ; the formula is as follows: ; ; ; ; ; Next, the edge server updates the stored challenges C A1 and C A2 to C A1+1 and C A2+1 , and replaces the old challenge-response pair data with the new data in the manner of a legitimate node, , , , , , and stores them in the secure database; the formula is as follows: ; ; Once Node A1 and Node A2 successfully pass the authentication of the edge server, Node A1 , Node A2 and the edge server will use Key2 as the session key for secure communication; finally, the authentication information is recorded in the edge server and recorded as a transaction in the edge blockchain network BCH.

[0032] S5: The two devices perform cross-domain communication.

[0033] The specific process of step S5 is as follows: S51: The two cross-domain devices are device Node A3 and device Node A4 , and device Node A3 first sends an association request to the edge server E3 to which it is connected; through step S22 and step S23 for identity authentication and key exchange, after the device authentication is successful, E3 sends a transaction to the blockchain Bch by providing the unique identifier OID A4 of device Node A4 and the edge server E4 connected to Node A4 ; S52: Bch verifies the given OID A4whether the corresponding unique identifier exists on the blockchain; if the verification passes, the process continues; otherwise, the process terminates and returns an error; S53: After successfully verifying the existence of the other device, Bch creates a block to store the mapping information of device Node A3 and Node A4 ; S54: Device Node A3 authenticates its identity and exchanges keys with the connected edge server E3 through steps S22 and S23. After successful device authentication, a session key Key A3 is generated between the edge server E3 and device Node A3 . The edge server E3 uses the public key Pk4 of the target edge server to encrypt the key Key A3 between the edge server E3 and device Node A3 to obtain the encrypted data packet M k . Subsequently, the encrypted data packet M k is sent to the edge server E4; S55: When the edge server E4 receives M k , it creates a new transaction block F and shares it with the edge network based on the blockchain. At the same time, it sends a connection establishment request to Node A4 . After receiving the request, Node A4 authenticates its identity and exchanges keys with the connected edge server E4 through steps S22 and S23. If the mutual verification between the edge server E4 and device Node A4 is successful, a communication key Key A4 is generated between the edge server E4 and device Node A4 ; otherwise, an error will be reported and the process ends; S56: Next, the edge server E4 verifies the validity of the block to ensure the legality of the block transaction; S57: Once the block passes the verification, the edge server E4 will use its private key Prk4 to decrypt Key k from M A3 ; encrypt Key A3 with Key A4 to obtain data M SK . Send M SK to device Node A4 . After receiving M A4 , device Node SK decrypts it with Key A4 to obtain Key A3 , thus completing cross - regional identity authentication and key exchange.

Claims

1. A lightweight security authentication method based on a hybrid authentication architecture, characterized in that, It includes the following steps: S1: Conduct centralized edge-level authentication and register the Internet of Things system; The specific process of step S1 is as follows: S11: Assign a unique identifier EID to each edge server, and generate a public key and a private key for each edge server; S12: Use system name S name Generate a unique group identifier GID for the IoT system using the hash of the corresponding edge server, and register the new IoT system with the nearest edge server; S13: Generate a unique object identifier OID to identify each object O in group G. In addition, the edge server generates a random input stimulus, i.e., a challenge C, for the physically unclonable function PUF, and collects the generated response R; then, store the challenge-response pair (C, R) in the secure database; R is collected and stored in the secure database of the edge server. For each device, only one challenge-response pair is stored during the registration phase; S2: Communicate the devices of the Internet of Things system with the edge server; The specific process of step S2 is as follows: S21: Initialize the connection between the device and the edge server; First, the device Node B sends a connection request message to the edge server. The connection request message contains the B unique identifier OID of the Node B ; After receiving the request, the edge server looks up the corresponding Node in the security database B 's challenge-response pair (C B , R B ), where C B represents the challenge of Node B , and R B represents the corresponding response to the found C B ; then, the edge server generates a random number RN1 and performs an XOR operation on RN1 and R B to obtain the encrypted message D B ; next, the edge server calculates the hash value H B of the message D B and R B to ensure the integrity of the information; finally, the edge server sends the message D B , H B and C B back to Node B ; the formula is as follows: ； ； Among them, represents an exclusive OR operation, represents a concatenation symbol, represents a hash function; S22: The device authenticates the edge server; S23: The edge server authenticates the device; S3: Determine whether the two devices that need to communicate are connected to the same edge server. If so, go to step S4; if not, go to step S5; S4: The two devices conduct in-domain communication; The specific process of step S4 is as follows: S41: Initialize the connection between the two in-domain devices; Two devices in the same domain are device Node A1 and device Node A2 respectively. Device Node A1 sends a connection request message to the edge server. The connection request message contains the unique identifier OID A1 of Node A1 and the unique identifier OID A2 of Node A2 . After receiving the connection request, the edge server checks whether Node A2 is registered through the database and sends a connection request to Node A2 . After receiving the connection request, Node A2 selects a flag and sends an N2N connection establishment request (OID A1 , OID A2 ) to the edge server. After receiving the N2N connection establishment request, the edge server obtains the corresponding challenge-response pairs (C A1 , R A1 , C A2 , R A2 ) from the security database and generates a random number RN2. C A1 represents the challenge of Node A1 , R A1 represents the response corresponding to C A1 . C A2 represents the challenge of Node A2 , R A2 represents the response corresponding to C A2 . The random number RN2 is respectively XOR-operated with R A1 and R A2 to obtain the encrypted messages D A1 and D A2 . The formula is as follows: ； ； Next, calculate R A1 and D A1 's hash value H A1 、R A2 and D A2 's hash value H A2 to verify the transmitted message; the edge server sends the data D A1 、H A1 and C A1 back to Node A1 , and sends the data D A2 、H A2 and C A2 back to Node A2 ; the formula is as follows: ； ； S42: The two in-domain devices authenticate the edge server; S43: The edge server authenticates the two in-domain devices; S5: The two devices conduct cross-domain communication; The specific process of step S5 is as follows: S51: The two devices across domains are device Node A3 and device Node A4 . Device Node A3 first sends an association request to the edge server E3 it is connected to; through step S22 and step S23 for identity authentication and key exchange, after successful device authentication, E3 sends a transaction to the blockchain Bch by providing the unique identifier OID A4 of device Node A4 , and the edge server E4 connected to Node A4 . S52: Bch verifies whether the given OID A4 and the corresponding unique identifier exist on the blockchain; if the verification passes, the process continues; otherwise, the process terminates and returns an error; S53: After successfully verifying the existence of the other device, Bch creates a block to store the mapping information of device Node A3 and Node A4 ; S54: Device Node A3 The edge server E3 to which it is connected performs identity authentication and key exchange through steps S22 and S23. After successful device authentication, the edge server E3 and the device Node A3 generate a session key Key A3 . The edge server E3 uses the public key Pk4 of the target edge server to encrypt the key Key A3 between the edge server E3 and the device Node A3 to obtain the encrypted data packet M k . Subsequently, the encrypted data packet M k is sent to the edge server E4; S55: When the edge server E4 receives M k it creates a new transaction block F and shares it with the blockchain-based edge network, and at the same time sends a connection establishment request to Node A4 Node A4 After receiving the request, it performs identity authentication and key exchange with the connected edge server E4 through steps S22 and S23. If the edge server E4 and the device Node A4 successfully authenticate each other, then a communication key Key A4 is generated between the edge server E4 and the device Node A4 otherwise, an error will be reported and the process will end; S56: Next, the edge server E4 verifies the validity of the block to ensure the legality of the block transaction; S57: Once the block is verified, the edge server E4 will use its private key Prk4 to obtain the k Decrypt Key A3 ; Key A3 Use Key A4 Encrypted data M SK , M SK Send to device Node A4 , device Node A4 Receive M SK Use Key later A4 Decrypt to get the Key A3 , thus completing the cross-region identity authentication and key exchange.

2. The lightweight security authentication method based on the hybrid authentication architecture according to claim 1, wherein In step S11, the trusted authority TA first sets a finite field parameter, i.e., selects a prime number p to construct the finite field Fp. On the finite field Fp, define an elliptic curve Eq(m,n), and its expression is as follows: Eq(m,n):y 2 =x 3 +mx + n; where: x, y ∈ Fp, x and y represent the abscissa and ordinate of the points on the elliptic curve respectively; m, n are the coefficient parameters of the elliptic curve, m, n ∈ Fp; after constructing the elliptic curve, calculate the point set G of the elliptic curve over the finite field Fp, and the point set G forms a finite additive group under the elliptic curve addition rule; subsequently, TA selects a base point g from the additive group, g ∈ G; the order of the base point g is q, and to ensure the non-singularity of the elliptic curve, it is required to satisfy the condition: 4m 3 + 27n 2 mod q ≠ 0, mod represents the modulo operation; TA randomly selects a private key Prk in the integer set Zq = {0, 1, 2,..., q - 1}, Prk ∈ [1, q - 1], and Prk is an integer satisfying 1 ≤ Prk < q; then, calculate the corresponding public key: Pk = Prk·g, where · represents the scalar multiplication operation, Pk is the public key corresponding to the private key Prk, and Pk ∈ G; finally, TA publishes the following public parameters to all edge servers participating in the identity authentication: {Eq(m, n), g, q, Pk}, at the same time, the private key Prk is only sent to and held secretly by the corresponding server and is not made public to the outside to ensure the security of the entire identity authentication process.

3. The lightweight security authentication method based on a hybrid authentication architecture according to claim 1, wherein The specific process of step S22 is as follows: Node B After receiving a message from the edge server, first use the embedded PUF instance to generate , as the response obtained according to C B ; then, Node B calculates the hash value of B and D and compares with the received H B to verify the integrity of the message; if the two are consistent, indicating that the message has not been tampered with during transmission, then Node B confirms the integrity of the message, proving that it is a legitimate request from the edge server; Node B performs exclusive-or decryption on the received message D B and to extract the random number RN1 and generate the key Key1; Once the Node B completes the authentication of the edge server, the Node B will generate a new challenge C B+1 and the corresponding response R B+1 , where C B+1 is the exclusive OR value of C B and R B ; then, XOR R B+1 with RN1 to generate the message D B+1 , and calculate the value of which is H B+1 , then send D B+1 and H B+1 to the edge server; the formula is as follows: ； ； ； ； ； ； ； ； Among them, represents the physical unclonable function of Node B , represents judging equality.

4. The lightweight security authentication method based on a hybrid authentication architecture according to claim 3, wherein The specific process of step S23 is as follows: Assume that the edge server receives H B+1 and the message , is the message corresponding to the received D B+1 . First, decrypt using the random number RN1 to recover the updated response of Node B . Next, calculate the hash value of and ; verify the correctness of the device response by comparing with the received H B+1 ;​​ If the hash verification is successful, it indicates that the device Node B has been successfully authenticated. The edge server then updates the challenge C B+1 and the response R B+1 and stores them in the secure database; once Node B successfully passes the authentication by the edge server, the edge server and Node B will use as the session key for secure communication; the formula is as follows: ； ； ； Next, the authentication information is recorded in the edge server and recorded as a transaction in the edge blockchain network BCH; Finally, the edge server updates the stored challenge to C B+1 , and replaces the old challenge-response pair data with the new data in the manner of a legitimate node, and stores it in the secure database; the formula is as follows: 。 5. The lightweight security authentication method based on a hybrid authentication architecture according to claim 4, wherein The specific process of step S42 is as follows: Node A1 After receiving the message from the edge server, it will first use the embedded PUF instance to generate , which is the response obtained according to the challenge C A1 of Node A1 ; then, Node A1 uses the generated to compare with the hash A1 of D and the received H A1 to verify the integrity of the message; the formula is as follows: ； ； Represents Node A1 's physically unclonable function; If is consistent with H A1 both, it indicates that the message has not been tampered with during transmission. Node A1 confirms the integrity of the message, proving that it is a legitimate request from the edge server; Node A1 performs an exclusive-or decryption on the received message D A1 and to extract the random number RN2 and generate the key Key2; once Node A1 completes the authentication of the edge server, Node A1 will update its PUF response. Node A1 generates a new challenge C A1+1 and the corresponding response R A1+1 through the PUF, and sends C A1+1 and R A1+1 back to the server, where C A1+1 is the exclusive-or value of C A1 and R A1 , and R A1+1 is the response obtained using the challenge C A1+1 ; next, XOR R A1+1 with RN2 to generate the string D A1+1 , and calculate the hash value of R A1+1 and D A1+1 which is H A1+1 . The formula is as follows: ； ； ； ； ； ； Similarly, Node A2 authenticates the server in the same way after receiving the message. Node A2 The formula for node authentication is as follows: ； ； ； ； ； ； ； ； Among them, represents the Physical Unclonable Function of Node A2 , is the challenge for Node A2 , is the response obtained according to , is the hash value of the XOR operation with D A2 , is the new challenge generated by Node A2 through PUF, is the corresponding response, is the string generated by the XOR operation with , is the hash value of the XOR operation with ; Node A1 Send the message {D A1+1 , H A1+1} to the edge server. Node A2 Send the message {D A2+1 , H A2+1} to the edge server.

6. The lightweight security authentication method based on a hybrid authentication architecture according to claim 5, characterized in that, The specific process of step S43 is as follows: The server receives the messages {D A1+1 , H A1+1} and the message {D A2+1 , H A2+1}. First, by performing an exclusive OR operation on D A1+1 and D A2+1 with the previously generated random number RN2, the updated PUF responses of Node A1 and the updated PUF response of Node and Node A2 are restored ; Subsequently, the edge server calculates the hash value of D A1+1 and , the hash value of D A2+1 and to check the integrity of the message; after the hash value verification is completed, the edge server successfully authenticates two IoT devices, namely Node A1 and Node A2 ; the formula is as follows: ； ； ； ； ； Next, the edge server will store the challenge C A1 and C A2 update to C A1+1 and C A2+1 , and replace the old challenge-response pair data with the new data in the manner of a legitimate node, , , , , , and store it in the secure database; the formula is as follows: ； ； Once Node A1 and Node A2 successfully pass the edge server authentication, Node A1 、Node A2 and the edge server will use Key2 as the session key for secure communication; finally, the authentication information is recorded in the edge server and recorded as a transaction in the edge blockchain network BCH.

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