Abstract: At a node device associated with a blockchain as a received target transaction, a target transaction published by a user is received, where the received target transaction includes transaction content, and where at least a part of the transaction content includes a content summary associated with target content that is stored in a third-party storage system connected to the blockchain. By the node device and to the third-party storage system, the target content corresponding to the content summary is queried. By the node device, whether the target content is verified is determined. In response to determining that the target content is verified, by the node device, the received target transaction is executed based on the transaction content. By the node device, the received target transaction is stored in a distributed database associated with the blockchain.

Abstract: Implementations of the present disclosure include identifying, by a relay that is communicatively linked with a first blockchain instance and a second blockchain instance in a unified blockchain network, a blockchain domain name of a first blockchain instance; identifying a blockchain domain name of the second blockchain instance; receiving, from a node of the first blockchain instance, an access request for accessing the second blockchain instance, wherein the access request including the blockchain domain name of the second blockchain instance; identifying a chain identifier of the second blockchain instance based on the blockchain domain name of the second blockchain instance, wherein the chain identifier of the second blockchain instance indicates a blockchain network configuration of the second blockchain instance; and providing access to the second blockchain instance for the first blockchain instance based on the blockchain network configuration indicated by the chain identifier of the second blockchai

Abstract: Implementations of the present disclosure include obtaining, by a client node of a first blockchain instance, a blockchain domain name of a second, different blockchain instance, wherein the blockchain domain name is a unique identifier of the second blockchain instance in a unified blockchain network including multiple blockchain instances that are communicatively linked by two or more relays, the blockchain domain name includes a human-readable label, and the blockchain domain name uniquely corresponds to a chain identifier of the second blockchain instance; identifying the chain identifier of the second blockchain instance based on the blockchain domain name of the second blockchain instance, wherein the chain identifier of the second blockchain instance indicates a blockchain network configuration of the second blockchain instance; and accessing, by the client node, the second blockchain instance based on the blockchain network configuration indicated by the chain identifier of the second blockchain insta

Abstract: Implementations of the present disclosure include obtaining, by a computing system, a unified blockchain domain name (a UBCDN) message of a blockchain instance, wherein the UBCDN message includes a UBCDN of the blockchain instance, a digital signature of an owner of the UBCDN of the blockchain instance (a UBCDN owner) on the UBCDN, and a domain certificate of the UBCDN; verifying whether the domain certificate of the UBCDN is issued by a trusted certificate authority (CA) using a public key of the CA; and verifying whether the UBCDN is issued by the UBCDN owner using a public key of the UBCDN owner. The UBCDN message includes a blockchain domain name and a chain identifier of the blockchain instance uniquely corresponding to the blockchain domain name.

Abstract: A data processing request is obtained containing blockchain data and an identifier used to identify a blockchain network to which the data processing request belongs. The identifier is extracted from the data processing request. Based on the identifier, corresponding processing logic associated with the data processing request is executed. The blockchain data is stored to a blockchain storage area corresponding to the identifier.

Abstract: A first certificate authority (CA) trust list comprising a plurality of CA identifiers is obtained by a first node of a blockchain network. A communication request comprising a public key certificate of the second node is received by the first node from a second node of the blockchain network. A first CA identifier is determined from the received public key certificate. A determination is made as to whether the first CA identifier matches one of the plurality of CA identifiers of the first CA trust list. In response to determining that the first CA identifier matches one of the plurality of CA identifiers of the first CA trust list, the communication request is approved by the first node. In response to determining that the first CA identifier does not match one of the plurality of CA identifiers of the first CA trust list, the communication request is denied.

Abstract: Implementations of the present disclosure provide techniques to improve security in blockchain networks. In some implementations, a linking request is received from a node. The node requests to be linked to a blockchain network. The linking request includes a digital code. One or more consensus verification messages are received from one or more blockchain nodes of the blockchain network. Each consensus verification message indicates whether a respective blockchain node approves or denies the linking request. A consensus verification result is determined based on the one or more consensus verification messages. In response to determining that the linking request is approved by the one or more blockchain nodes, the digital code is stored into the blockchain network as a digital certificate of the node.

Abstract: A first communication request including a digital certificate of a first node sent from the first node in a blockchain is received at a second node in the blockchain, where the digital certificate of the first node is stored in the blockchain. Certificate validity information stored in the blockchain and associated with the nodes in the blockchain is accessed by the second node based on the first communication request, where the certificate validity information reflects the validity status information of digital certificates of the nodes in the blockchain. A verification of whether the digital certificate of the first node is valid is performed by the second node based on the first communication request and the accessed certificate validity information. A communication connection to the first node is established by the second node in response to verifying that the digital certificate of the first node is valid.

Abstract: A communication request sent by a second node in a blockchain network is received by a first node in the blockchain network. Whether the second node has a mapping relationship with the first node is determined by the first node. A communication connection to the second node is established by the first node in response to determining that the second node has a mapping relationship with the first node. Establishment of a communication connection to the second node is refused by the first node in response to determining that the second node does not have a mapping relationship with the first node.

Abstract: Techniques for providing a digital certificate management for blockchain technologies are described. One example method includes a transaction request including a digital certificate is received from a certificate authority at a node in a blockchain network, and the transaction request is a request to write the digital certificate into a blockchain associated with the blockchain network, and the digital certificate is issued to a node in the blockchain network. A consensus verification result is determined for the transaction request, and the consensus verification result is produced by nodes in the blockchain network. The consensus verification result is compared to a predetermined threshold value. In response to determining the consensus verification result is greater than or equal to the predetermined threshold value, the digital certificate is stored in the blockchain associated with the blockchain network.

Abstract: A data processing request is obtained containing blockchain data and an identifier used to identify a blockchain network to which the data processing request belongs. The identifier is extracted from the data processing request. Based on the identifier, corresponding processing logic associated with the data processing request is executed. The blockchain data is stored to a blockchain storage area corresponding to the identifier.