57 results about "Trust third party" patented technology

Example systems and methods include: receiving, by a computing system, a request to add a block to a blockchain, wherein the block includes an entry that relates to a semantic representation, wherein the semantic representation encodes a state change to a state stored on the blockchain; obtaining, by the computing system, a copy of the semantic representation as provided by a trusted third party, wherein the copy of the semantic representation is digitally signed by the trusted third party or provided by the trusted third party at a network address; validating, by the computing system, the semantic representation; and initiating, by the computing system, procedures to add the block to the blockchain.

The invention provides a threshold access system supporting threshold decryption and an NTRU type multi-party homomorphic encryption method, and belongs to the technical field of information security and data security. The threshold access system supporting threshold decryption comprises an initialization stage, a key generation stage, a secret share sharing stage, an encryption stage, a decryption stage, a homomorphic calculation stage and a data reconstruction stage, and a new NTRU type multi-party homomorphic encryption method is realized based on the threshold access system. Comprising an initialization stage, a key generation stage, an encryption stage, a decryption stage and a homomorphic calculation stage, so that the method can be more suitable for application scenarios of highly sensitive data processing, the dependence on a trusted third party is very small, the communication overhead and the calculation overhead are very small, the privacy of data is ensured, subdomain lattice attacks can be resisted, and the security of the data is improved. And the efficiency is relatively high.

The invention relates to the fields of cryptographic algorithms and homomorphic encryption, in particular to an anti-quantum-attack homomorphic encryption method. Along with increasing demands of outsourcing computing and privacy protection application in a multi-user scene, multi-key homomorphic encryption becomes an important research direction. The construction of a traditional multi-key homomorphic encryption scheme generally depends on a common random character string (CRS) model, and a trusted party needs to generate a common parameter for a public key so as to support calculation on a joint ciphertext. Due to the dependence on the central trusted mechanism, the anti-attack capability and the decentralization characteristic of the system are greatly reduced. In order to avoid excessive dependence on trusted third parties and public parameters, a distributed key generation protocol is used in the invention, all users are enabled to independently generate keys thereof, and ciphertexts of a plurality of users are expanded to the same dimension through a ciphertext expansion technology, so that the encryption efficiency is improved. Therefore, multi-key homomorphic encryption in a multi-user scene is realized without depending on a trusted third party, a lattice-based CRS-free multi-key homomorphic encryption method is provided, and the security and decentration characteristic of the scheme are enhanced. Furthermore, the invention provides a directional decryption mechanism and introduces the directional decryption mechanism into the scheme, the public key information of the target user is embedded into the ciphertext, it is ensured that only the specific target user can decrypt the ciphertext after homomorphic operation, and more flexible privacy protection is provided.

The invention relates to the field of secure multi-party communication and quantum cryptography, and provides a dynamic quantum message authentication method capable of identifying suspension. Comprising the following steps: in a stage of screening honest participants by a semi-quantum trusted third party SQ-TTP, dynamically grouping the participants by the SQ-TTP, randomly selecting part of the participants to form a small quantum communication network for message transmission, and screening honest participants not less than the grouping number according to a message authentication result; in a quantum message parallel transmission stage of each group, the SQ-TTP appoints the screened honest participants as receivers of each group, and the participants in the group complete message transmission in a quantum message transmission mode similar to that in the screening stage; in the stage that the SQ-TTP and each packet receiver transmit the received message to the server, the server decrypts the message by using the key sent by the SQ-TTP and authenticates the message by measuring trap quantum bits. The method is suitable for a large-scale quantum communication network, the quantum resource consumption is reduced through dynamic grouping and parallel transmission, and the message transmission efficiency is improved.

The invention discloses a privacy protection federated learning method based on result-agnostic function encryption, and the method comprises the steps: dividing a derived key assembly into a plurality of shares, and carrying out the reconstruction through the remaining shares even if a part of clients are offline and the key shares are missing, thereby guaranteeing that a function key can be recovered, and an encryption model can be correctly aggregated, and improving the privacy protection efficiency. And the robustness and fault tolerance of the system are greatly improved. A non-interactive key exchange technology is adopted, and a secret sharing mechanism is combined, so that a client can generate a private key in a collaborative manner under the condition that no trusted third party participates, the deployment complexity is reduced, and the security and expandability of the system are improved. A function encryption process with an unknown result is designed, only an intermediate result in an encrypted state is output in an aggregation stage, and decryption is finally completed by local joint of a client, so that the possibility of snooping an aggregation result and reversely deducing original data by a server under a semi-honesty model is fundamentally avoided, and data privacy in a federated learning process can be effectively guaranteed.

The invention aims to provide a decentralized edge data integrity batch verification method and system, and the method comprises the steps: taking any industrial edge server as an initiator, sending a data integrity verification request to an intelligent contract, and collecting the response of a candidate; after the response of any candidate is collected through the smart contract, selecting an optimal verifier combination from the candidates; the reward allocation and reputation update are performed, and the reward is allocated to the verifier by contribution to significantly reduce communication overhead and verification latency. According to the method disclosed by the invention, the verification delay and the communication overhead can be remarkably reduced without depending on a central trusted third party, and the special requirements of the industrial Internet of Things are met.

The application provides a third-party-based key exchange method and system, a trusted third party and an entity, wherein the trusted third party only participates in identity authentication of the entity and assists in negotiation of a key between the two entities, and cannot obtain a shared key between the two entities, effectively solving the problem that the trusted third party cannot avoid obtaining the exchanged key in the existing key exchange scheme based on the trusted third party, and ensuring that the finally exchanged key is only owned by the two entities participating in the key exchange. In addition, in the application, the trusted third party can also provide a random number to participate in the final key generation, thereby ensuring the strength of the final key, meeting the requirement that the trusted third party needs to manage the strength of the exchanged key in a specific application scenario, and enhancing the management and control capability of the system.

We provide computing systems and methods for communicating with customer devices and trusted third parties. [Solution] In the currency conversion system, the network interface receives customer identity data and a request to restore the customer wallet from the customer device. The processor verifies the customer identity data received from the customer device. Once the processor has verified the customer identity data received from the customer device, the network interface communicates a request to a trusted third-party key repository for a first key associated with the customer wallet. The processor uses the first key associated with the customer wallet and a second key associated with the customer wallet to restore the customer wallet.

The application belongs to the technical field of encryption, and provides an anti-quantum threshold encryption method and system, wherein a trusted third party generates system parameters, uniformly and randomly generates a matrix, samples a secret vector and a noise vector, calculates a public key vector, and discloses the matrix and the public key vector as a public key; a unique and public identification value is allocated to each authorized accesser, a private key share is calculated, and the private key share is sent to the authorized accesser respectively; a data owner acquires a message to be encrypted and the public key, calculates a ciphertext, and the ciphertext comprises a first component and a second component; an authorized accesser participating in decryption reads the first component of the ciphertext, calculates a partial decryption value, and sends the identification value and the partial decryption value to the trusted third party; when the trusted third party receives the partial decryption values of no less than a threshold parameter, Lagrange coefficients are calculated, an aggregated decryption value is calculated, the decryption of the ciphertext is carried out, and the obtained result is sent to the authorized accesser participating in decryption. The application can guarantee the confidentiality of the message.

The invention relates to the technical field of data security, in particular to a bank asset electronic auction algorithm based on homomorphic encryption, which comprises key generation and distribution, hybrid encryption quotation, threshold decryption and verification and result publication. Compared with the prior art which depends on a non-completely trusted third party to realize the auction process, the scheme adopts a decentralized (t, n) threshold decryption mechanism, combines a Shamir secret sharing technology, splits a private key into multiple parts and distributes the multiple parts to all participants, and decryption needs at least t nodes to cooperate to complete. In the prior art, a centralization risk is caused by dependence on a single third party, and control by an attacker or single-point failure is easily caused; according to the scheme, through distributed key management and threshold verification, third-party dependence is eliminated, it is ensured that even if part of nodes are malicious or invalid, the result can still be safely decrypted and verified, and the collusion attack resistance and fault tolerance of the system are remarkably improved.

The application discloses a mass interface call log storage and tracing method and system based on a blockchain, belongs to the technical field of the blockchain, and aims to solve the problems of mass interface call log storage difficulty and data sharing tracing difficulty in a data sharing mode. A service gateway pushes a call log to a Kafka cluster; the Kafka cluster consumes the call log and stores the consumed call log in batches to an ES system through logstash; a log collection system uploads a total hash value corresponding to the batch call log to the blockchain, the blockchain returns a transaction hash value to the log collection system, the log collection system returns the transaction hash value to the ES system and associates the transaction hash value with the corresponding batch call log; a trusted third party calculates a total hash value of the corresponding batch call log, compares the obtained total hash value with the total hash value queried from the blockchain, and determines that the call log is trusted if the total hash values are consistent.

The disclosed technology provides for managing, authenticating, and authorizing data sharing between parties utilizing multi-party-computation ("MPC"). A method can include: receiving, by a server from a party B system, (i) a request to access first data of a party A system and (ii) second data of party B, sending, to the party systems, an authorization request to authorize the request, receiving, from the party systems, MPC shares associated with trusted third party processing of data, the MPC shares generated as part of a digital contract between the parties for combining the first and second data within an environment of the trusted third party, to which neither party has access, retrieving MPC authorization functions associated with the digital contract, determining whether the requested access is authorized based on the MPC shares and MPC authorization functions, and performing data processing operations using the first and second data in a secure environment.

Embodiments of the present disclosure provide a multimedia data stream processing method and apparatus, an electronic device and a storage medium. The method comprises: receiving stream pushing related data sent by a stream pushing node, wherein the stream pushing related data corresponds to a pushed multimedia data stream; determining a target processing policy on the basis of the stream pushing related data and reception related data of a received processed multimedia data stream forwarded by a trusted third party; and when the target processing policy is a stream repushing policy, creating a data transmission link corresponding to the trusted third party and a current receiver so as to push, on the basis of the created data transmission link, the multimedia data stream pushed by the stream pushing node to the trusted third party. The technical solution provided by the embodiments of the present disclosure can ensure that the trusted third party forwards the multimedia data stream to the current receiver, achieving the effect of improving the forwarding service quality and stability.

The application discloses a privacy-enhanced data aggregation method supporting off-line fault tolerance and deviation correction. The method efficiently packs multi-dimensional data by using the Chinese remainder theorem, and realizes ciphertext aggregation without a fully trusted third party by introducing a collaborative mask based on neighbor relationship and a special mask shared by SM and CC, thereby guaranteeing data and identity privacy. Meanwhile, a deviation correction recovery mechanism executed unidirectionally by a control center is designed. The mechanism reconstructs a residual mask by using information such as a frozen candidate set and an effective participation set, thereby recovering a real aggregation result without requiring a node to respond secondly or an off-line node to supplement transmission. Performance evaluation shows that, compared with existing advanced schemes, DBPMDA reduces the additional communication and calculation overhead of the system in the case of device off-line, and is suitable for a resource-limited smart grid Internet of Things environment.

The present invention provides a method and system for flexible data sharing based on public key and attribute-based encryption, belonging to the field of data encryption technology. In the solution of the present invention, a trusted third party generates system public parameters PP and a master private key MSK; an ordinary public key encryption user generates an ordinary public key PK and an ordinary private key SK; the trusted third party generates a user attribute-based private key SK based on the user attribute set S ABE ; the ordinary public key encryption user encrypts the data plaintext M to obtain an ordinary public key encrypted ciphertext CT; the ordinary public key encryption user generates a conversion key RK, and at the same time sets an access control policy to limit the usage right of the conversion key RK; the cloud service provider uses the conversion key RK to convert the ordinary public key encrypted ciphertext CT into an attribute-based encrypted ciphertext CT'; the attribute-based encryption user uses the user attribute-based private key SK ABE to decrypt the attribute-based encrypted ciphertext CT' and output the data plaintext M. The present invention can directly convert the ordinary public key encrypted ciphertext specified by the user into an attribute-based encrypted ciphertext.

The present invention discloses a secure and verifiable federated learning scheme with low communication volume and resistance to tampering attacks and deletion attacks, comprising the following steps: (1) initialization: a trusted third party generates initialization parameters and a public-private key pair for each user and distributes them to the corresponding users; (2) secret sharing: each user generates a mask and shares the mask with each user through secret sharing technology; (3) encryption and proof generation: the user uses the mask to encrypt the local update to be uploaded and generates a proof for the unencrypted local update for subsequent correctness verification and resistance to spoofing attacks; (4) aggregation verification: the trusted third party collects the user's proof to generate a verification proof, and the server requests to restore the mask of the offline user; (5) aggregation update: the user verifies the server's request. If the verification is successful, the server restores the mask and then aggregates the updates uploaded by the user; (6) correctness verification: the user verifies the correctness of the aggregation result sent by the server.

The present invention discloses a method for aggregating intelligent IoT data without a trusted third party, and relates to the technical field of IoT. A plurality of resource nodes and a resource node management center are set, and the types of IoT data collected by the resource nodes are distinguished by a multi-classification fusion method based on fuzzy measurement. Each resource node autonomously generates a public and private key and encrypts the IoT data to generate a ciphertext. A plurality of aggregation nodes are set to aggregate different types of ciphertexts. An operation center identifies the type of the aggregated ciphertext and selects a port to a corresponding business node. The business node decrypts the aggregated ciphertext to obtain aggregated data, thereby achieving the distinction and aggregation of multiple types of IoT data without a trusted third party, improving the data transmission efficiency, avoiding the security problems caused by external attacks and internal collusion attacks, and improving the reliability of IoT data transmission protection.

A method, system, device and medium for defending against poisoning attacks in vertical federated learning, an active party and passive party interaction data integrity verification scheme is designed for the classic vertical federated learning algorithm Secureboost, the method is: key generation and distribution; the active party encrypts the Boost tree gradient information, and sends the encrypted result to the passive party, and sends the encrypted Boost tree gradient information to the trusted third party after homomorphic hash encryption; the passive party aggregates the received encrypted gradient information according to the feature dimension, and then performs homomorphic hash on the aggregation result and sends it to the trusted third party; the trusted third party aggregates all the information sent by the passive party, and then verifies whether the encrypted Boost tree gradient information sent by the active party and the aggregation result of the passive party information are consistent, if consistent, the integrity verification is passed, otherwise the verification is failed; the system, device and medium based on the above method defend against poisoning attacks, realize the safe aggregation of global model, and improve the defense reliability of poisoning attacks.

The invention discloses a lightweight privacy protection vehicle formation building method, which adopts a multi-level encryption mechanism from pilot vehicle selection and member attribute matching in a formation forming stage to feedback aggregation and reputation updating in a formation disintegration stage, and ensures the confidentiality and integrity of sensitive data (such as reputation values, attributes and feedback reports). Through dynamic bucket mapping, random vector perturbation and lightweight ciphertext calculation, the method significantly reduces calculation and communication overhead while guaranteeing privacy, and solves the core problems that a traditional scheme depends on a trusted third party, is susceptible to association attacks, is insufficient in dynamic adaptability and the like. The technical framework can be widely applied to logistics fleet collaborative transportation, urban intelligent bus formation scheduling, automatic driving vehicle group collaboration and other scenes, and safe and reliable technical support is provided for large-scale deployment of an intelligent traffic system.

The application discloses a kind of fusion attack traceability and data integrity audit federated learning method and system, the method includes: trusted third party initializes system parameter, system parameter and initial model parameter are sent to all clients;Gradient and four characteristics returned by each client are received, attack traceability and reputation evaluation are carried out to four characteristics, determine the client set of next round continues training;Gradient set is sent to aggregation server after encryption, receive the encrypted aggregation gradient returned by aggregation server, obtain aggregation gradient plaintext by decryption;The present application is processed by client homomorphic encryption, attack detection and traceability, secure multi-party aggregation, encrypted reputation management, hierarchical process of independent integrity verification, malicious attack is identified and traced to next round training before model, so that attack detection is realized under the premise of guaranteeing privacy not to leak, reduce the overall security risk of federated learning system.

The application relates to the fields of secure multi-party communication and quantum cryptography, and discloses a dynamic quantum message authentication method capable of identifying suspension, which comprises the following steps: a semi-quantum trusted third party (SQ-TTP) screening honest participant phase, in which the SQ-TTP dynamically groups the participants, randomly selects part of the participants to form a small quantum communication network for message transmission, and screens out no less than the number of groups of honest participants according to the message authentication result; a parallel transmission of quantum messages of each group phase, in which the SQ-TTP specifies the screened honest participants as the receivers of each group, and the participants in the group complete the message transmission by adopting a quantum message transmission mode similar to that in the screening phase; and a stage of transmitting the received messages to a server by the SQ-TTP and the receivers of each group, in which the server decrypts the messages by using the key sent by the SQ-TTP, and authenticates the messages by measuring the trap qubits. The application is applicable to a large-scale quantum communication network, and can reduce the consumption of quantum resources and improve the message transmission efficiency by dynamic grouping and parallel transmission.

The present invention provides a secure aggregation method based on random exchange and key homomorphic pseudorandom functions, specifically comprising: in an initial stage, a user randomly selects n other users and exchanges the generated random numbers with them respectively; after the exchange, the total amount of the users' random numbers is calculated and sent to a control center; in a sending stage, a ciphertext is formed by a modular addition homomorphic operation based on the current time period, the user's electricity consumption, and the key obtained in the initial stage, and the ciphertext is summed up at the gateway and sent to the control center; in a decryption stage, the obtained ciphertext sum and the total amount of random numbers corresponding to the ciphertext sum are decrypted to obtain the total electricity consumption; in a management stage, new users are added, old customers are withdrawn, or the user's smart meter malfunctions are managed. The beneficial effects of the present invention are: no trusted third party is required, multiple solutions are adaptable, implementation is convenient, user management is lightweight, and while ensuring the security and accuracy of the results, additions and deletions can be freely made, resulting in strong applicability.

The invention relates to an anonymous data submission method based on a hash mask, and belongs to the technical field of data security. According to the method, all data senders generate session keys between every two data senders under the assistance of a data receiver, and then the senders randomly join one of m groups respectively; all data senders generate unique serial numbers which are different from one another under the condition that a trusted third party does not need to participate, and it is guaranteed that the values of the serial numbers can be deduced by no other entities except the data senders; all the data senders carry out packaging protection on own data by using own serial numbers and session key sequences; a data receiver obtains all the packaged data and unpacks the packaged data to obtain a set of original plaintext data, but cannot deduce the source of the data. According to the method and the device, the data receiver can obtain the data submitted by the data provider without a trusted third party, and the data receiver cannot deduce the source of the data, so that the identity anonymity of the data provider is guaranteed.

The present invention relates to the technical field of traffic prediction, and specifically relates to a method and system for crowd traffic prediction based on multi-party vertical federated learning, which are as follows: Multiple data holders perform local feature encoding, perform spatio-temporal feature encoding on the spatio-temporal crowd traffic data of the spatio-temporal traffic data holder, perform external factor feature encoding on the external factor data of the external factor data holder, and then perform encryption and differential privacy protection on the encoded features of each party through privacy-preserving distributed joint modeling. Then, the encrypted features after encryption and privacy protection are transmitted to the global module of the trusted third party. Finally, the encrypted features of the global module of the third party are decrypted, crowd traffic prediction is performed based on the decrypted features, and the local models of each data holder are updated. It can effectively solve the prediction problem of the mobile crowd traffic of dispersed data sources by utilizing the cross-domain collaboration of spatio-temporal traffic data and external factors on the premise of ensuring data privacy and security.

The invention relates to a multi-key fully homomorphic encryption method supporting multiple hops, and belongs to the technical field of computer application. The trusted third party selects public parameters and sends the public parameters to all participating users; each user i sends the first component bi to a trusted third party; the trusted third party calculates a joint public key pk; each user i calculates a ciphertext cti; calculating a polynomial di, 2 by each user i; generating a ciphertext Di as an expansion component; when the user with the serial number of N + 1 is newly added, calculating an update variable Ki, and sending the update variable Ki to the user i; each original user i calculates an active update component Li, 0 and sends the active update component Li, 0 to the trusted third party; calculating a passive update component Li, 1 of the user i, and sending all Li, 1 and the public key pkN + 1 to a trusted third party; the trusted third party updates the new ciphertext to nct; updating the new joint public key pk; according to the method, the additive property of the BFV type multi-key fully homomorphic encryption ciphertext component without ciphertext extension and the multiplication property of secrets which can be realized by single encryption are considered, the updating of the ciphertext to a new user can be realized, and the method has a wider application prospect.

The application discloses a kind of distributed flow table item effective time dynamic hopping implementation methods, including distributed flow table item effective time dynamic hopping definition, implementation, and balance security, performance and resource consumption three features such as characteristic.This method, flow table item in flow table existence time is regarded as privacy, through the ladder random response mechanism of differential privacy in SDN forwarding equipment local flow table item in flow table existence time is dynamically disturbed, forms dynamic mobile flow table item attack surface, makes low-speed flow table overflow attack unable to synchronize flow table item attack surface, to the attack has realized effective active defense.The method does not need to upgrade existing SDN interface protocol and controller software, does not need to introduce trusted third party, while considering network security, guarantee network performance and expansibility, especially suitable for various types of need to support high security and large concurrent user, and has special requirements to delay and expansibility, guarantee its service quality and user experience.

The disclosed technology provides for managing, authenticating, and authorizing data sharing between parties utilizing multi-party-computation ("MPC"). A method can include: receiving, by a server from a party B system, (i) a request to access first data of a party A system and (ii) second data of party B, sending, to the party systems, an authorization request to authorize the request, receiving, from the party systems, MPC shares associated with trusted third party processing of data, the MPC shares generated as part of a digital contract between the parties for combining the first and second data within an environment of the trusted third party, to which neither party has access, retrieving MPC authorization functions associated with the digital contract, determining whether the requested access is authorized based on the MPC shares and MPC authorization functions, and performing data processing operations using the first and second data in a secure environment.

The present application provides a cross-border data verification system and method. In this system, it includes a data subject, an overseas recipient, and a domestic agent with a domestic trusted third party. The data subject sends the first data security certification document of the target cross-border data and the data subject identity identifier to the overseas recipient. The overseas recipient performs data encryption processing on the first data security certification document and the data subject identity identifier to obtain a second data security certification document and a cross-border business identifier, and sends at least one of the second data security certification document and the cross-border business identifier to the domestic agent and the data subject. The domestic agent verifies the target cross-border data based on the first data security certification document, the second data security certification document, the data subject identity identifier, and the cross-border business identifier stored by the domestic trusted third party, obtains the target verification result, and sends it to the overseas recipient, thereby achieving the effect of improving the verification security of cross-border data.

This invention discloses an efficient threshold multi-party computation method and system based on homomorphic encryption in a decentralized model. The method specifically includes the following steps: (1) each participant agrees on common parameters; (2) each participant generates its own private key; (3) each participant uses its private key multiplied by the parameters and adds noise to generate a public key; (4) each participant uses its public key to encrypt its own plaintext to obtain ciphertext; (5) each participant expands the ciphertext; (6) addition and tensor product function calculations are performed, and the calculated ciphertext is output; (7) the ciphertext from step (6) is relinearized; and (8) the ciphertext from step (7) is decrypted. This invention can solve the problems of trusted third parties, algorithm paralysis after participant corruption, and low efficiency in relinearization in existing multi-party computation based on homomorphic encryption in cloud computing.

The present invention relates to the field of network information security technology, and in particular to an access token application control method based on an attribute encryption mechanism, comprising the following steps: S1, a trusted third party generates public parameters of the attribute encryption mechanism: Setup(λ)→(params, mpk, msk), generates system parameters params, a master public key mpk, and a master private key msk; S2, the trusted third party generates a private key of a user attribute ω for a user: KeyGen(mpk, msk, ω); S3, a server performs attribute encryption on the access token: Encrypt(mpk, A, m): encrypts the access token m∈{0, 1}* in the set of authorized user attribute strings A; S4, the user receives the ciphertext access token and performs attribute decryption: Decrypt(ct, sk): decrypts the ciphertext access token ct using the user's private key sk. The present invention can encrypt the access token using the attribute encryption mechanism according to the user's access permission attributes, thereby ensuring that the access token cannot be correctly decrypted even if the attributes are changed due to a change in user permissions or a network attack.