Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for consensus system downtime recovery. One of the methods includes: obtaining a pre-prepare message from the primary node; multicasting a prepare message indicating an acceptance of the pre-prepare message to at least some of the primary node and the other (N?2) backup nodes; obtaining (Q?1) or more prepare messages respectively from (Q?1) or more of the backup nodes; storing the pre-prepare message and the (Q?1) or more prepare messages; multicasting a commit message to at least some of the primary node and the other backup nodes, the commit message indicating that the one backup node agrees to the (Q?1) or more prepare messages; and obtaining, respectively from Q or more nodes among the primary node and the backup nodes, Q or more commit messages each indicating that the corresponding node agrees to (Q?1) or more prepare messages.

Abstract: Implementations of the present specification disclose graph structure model training and junk account identification methods, apparatuses, and devices. The solution includes: obtaining an account medium network graph, a node in the account medium network graph representing an account and a medium, and at least some edges indicating that a login behavior relationship exists between nodes connected by the edges; obtaining feature data and risk labeling data of the node, the feature data reflecting a login behavior of the corresponding node in a time sequence; and training, based on the account medium network graph, the feature data, and the risk labeling data, a predefined graph structure model for identifying a junk account.

Abstract: A method: broadcasting a first message comprising an apparatus type through near field communication; scanning a digital object identifier (DOI) that is displayed by a mobile terminal according to the first message and that matches the apparatus type, to obtain service information and identity information of the mobile terminal included in the DOI; broadcasting a second message generated based on the identity information; obtaining, from the mobile terminal, a request for a near field communication connection, the request being generated by the mobile terminal after the mobile terminal determines the second message includes information consistent with the identity information of the mobile terminal; verifying the request based on the identity information of the mobile terminal; in response to that the verification succeeds, establishing the near field communication connection to the mobile terminal; and executing a service through the near field communication connection according to the service information.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based cross-entity authentication are provided. One of the methods includes: obtaining, from a blockchain, a blockchain transaction comprising an authentication request by a first entity for authenticating a user, wherein the authentication request comprises a decentralized identifier (DID) of the user; in response to determining that the first entity is permitted to access authentication information of the user endorsed by a second entity, obtaining an authentication result of the user by the second entity in response to the obtained blockchain transaction, wherein the authentication result is associated with the DID; generating a different blockchain transaction comprising the authentication result; and transmitting the different blockchain transaction to a blockchain node for adding to the blockchain.

Abstract: Disclosed are a service processing method and apparatus, and a service server. The method comprises: receiving an operation request, sent by a first client device, for requesting to perform a service operation; generating a target service random code for a first account according to the operation request; receiving an operation response that is sent by a second client device according to the target service random code; identifying the first account by using the operation response; and sending account information of the first account to the second client device, so that the second client device completes the service operation based on the account information. In embodiments of the present application, a service processing process is completed based on a service random code that is generated by a service server in real time; therefore, security is relatively high, and interference from the external natural environment is avoided, and reliability of service processing can be effectively improved.

Abstract: A method for processing a transaction request, implementable by a first transaction node, may comprise: acquiring transaction data of a target transaction, wherein the first transaction node participates in the target transaction; determining, according to the transaction data, a transaction abstract after a plurality of transaction nodes each sign a data abstract of the transaction data, wherein the transaction nodes comprise at least the first transaction node and one or more second transaction nodes; generating a transaction request that comprises the transaction abstract; and broadcasting the transaction request to one or more consensus nodes, causing the consensus nodes to each save the transaction abstract in the transaction request into a blockchain after the transaction abstract passes consensus verification, the consensus nodes being blockchain nodes, wherein the transaction nodes and the consensus nodes are blockchain nodes of a blockchain network.

Abstract: A method includes: training a prediction model with sample data; obtaining user information of a user as an input feature to the prediction model; predicting, using the prediction model according to a set of determination conditions, whether the user has forgotten a payment password associated with a payment application; and in response to predicting that the user has forgotten the payment password and detecting the user logging in the payment application with a login password different from the payment password, displaying a user interface for directing the user to a payment password resetting interface for resetting the payment password.

Abstract: Disclosed in the present application are a card-based information displaying method and apparatus, and an information displaying service processing method and apparatus. The card-based information displaying method comprises: determining target information to be displayed and a card type of a first card for displaying the target information; determining whether a configuration version of a client supports the card type of the first card; when it is determined that the configuration version of the client does not support the card type of the first card, determining an association identifier corresponding to the first card, and associating with a second card supported by the configuration version of the client according to the association identifier; and displaying the target information of the client using the second card.

Abstract: Techniques for processing blockchain data are described. A node in a blockchain network receives service data generated by a first service, wherein the service data comprises a data structure having a field a value of which indicates that the first service is associated with a first processing level. The node stores, based on the value of the field, the service data in a first data processing queue selected from a plurality of data processing queues, wherein the first data processing queue corresponds to the first processing level, and each of the plurality of data processing queues corresponds to a different processing level. The node generates a new block that stores the service data read from the first data processing queue, and additional service data read from one or more of the plurality of data processing queues.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based notification are provided. One of the methods includes: obtaining information in a block of a blockchain to determine a current state of a workflow, wherein a blockchain contract deployed in the blockchain is executable to update the current state among one or more states of the workflow; updating a locally-maintained state machine based on the determined current state; and in response to determining that the updated state machine corresponds to one of the one or more states, transmitting a notification message to one or more subscribers subscribing to the one state.

Abstract: One or more embodiments of the specification provide a blockchain-based relationship binding method, apparatus, and device. An exemplary method may include: receiving a user binding request including a binding tag, the binding tag includes (1) a binding type of a binding relationship, and (2) role information of the second user in the binding relationship; sending a confirmation request to a second user; retrieving a relationship table of the second user; in response to the binding type in the user binding request includes a one-to-one binding relationship: determining whether the one or more binding types in the relationship table of the second user include the binding type in the user binding request, and if yes, terminating the method; and generating a record of binding relationship; writing the record of binding relationship into a blockchain; and updating the relationship table in the local database.

Abstract: A computer-implemented method comprises: committing a transaction amount t of a transaction with a commitment scheme to obtain a transaction commitment value T, the commitment scheme comprising at least a transaction blinding factor r_t; encrypting a combination of the transaction blinding factor r_t and the transaction amount t with a public key PK_B of a recipient of the transaction; and transmitting the transaction commitment value T and the encrypted combination to a recipient node associated with the recipient for the recipient node to verify the transaction.

Abstract: A method for audio recognition comprises: dividing audio data to be recognized to obtain a plurality of frames of audio data; calculating, based on audio variation trends among the plurality of frames and within each of the plurality of frames, a characteristic value for each frame of the audio data to be recognized; and matching the characteristic value of each frame of the audio data to be recognized with a pre-established audio characteristic value comparison table to obtain a recognition result, wherein the audio characteristic value comparison table is established based on the audio variation trends among the frames and within each of the frames of sample data.

Abstract: A method for starting an operation process comprises: receiving an operation request message from a terminal device in response to the terminal device scanning a barcode to obtain barcode information and determining an address of the server based on the barcode information, the operation request comprising an image of text associated with the barcode scanned by the terminal device, and the image of text specifying an operation function; determining text content based on the image of text; searching a correspondence relationship between different text content and respective operation access information to obtain operation access information corresponding to the determined text content; and returning the operation access information to the terminal device, for the terminal device to start an operation process by using the operation access information, the operation process having the operation function specified by the received image of text.

Abstract: A payment card binding method, a trust evaluation method, an apparatus, and an electronic device are provided. The payment card binding method includes: receiving a payment card binding request; sending a payment request to a payment system; in response to the payment request being successfully processed by the payment system, determining (1) an account trust level, (2) a device trust level, and (3) an environment trust level; inputting the account trust level, the device trust level, and the environment trust level into a trained classifier to determine a new card trust level (NCTL); determining a payment limit restriction for the digital wallet account using the payment card on the computing device; and binding, based on the NCTL and the payment limit restriction, the digital wallet account with the payment card for the digital wallet account to use the payment card for future payments.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for blockchain-based cross-entity authentication are provided. One of the methods includes: obtaining an authentication request by a first entity for authenticating a user, wherein the authentication request comprises a decentralized identifier (DID) of the user; in response to determining that the first entity is permitted to access authentication information of the user endorsed by a second entity, generating a blockchain transaction for obtaining an authentication result of the user by the second entity, wherein the authentication result is associated with the DID; and transmitting the blockchain transaction to a blockchain node for adding to a blockchain.

Abstract: Embodiments of the present specification disclose random walking and a cluster-based random walking method, apparatus and device. A solution includes: obtaining information about each node included in graph data, generating, according to the information about each node, a hash table reflecting a correspondence between the node and an adjacent node of the node, and generating a random sequence according to the hash table, to implement random walking in the graph data. The solution is applicable to clusters and single machines.

Abstract: Methods, systems, and apparatus, including computer programs encoded on computer storage media, for claim verification. One of the methods includes: receiving, from a first entity, a request for verifying a verifiable claim (VC) that comprises a digital signature; obtaining, based on the VC, a public key associated with a second entity; determining that the digital signature is created based on a private key associated with the public key; and verifying the VC based on the determination.