Terms

Bitcoin

Bitcoin is a world-renowned form of electronic cash proposed by Satoshi Nakamoto in 2008 — the first major application of blockchain technology.

Blockchain

A blockchain is a peer-to-peer network where each participant has access to a shared ledger. Transactions and history records cannot be removed or altered. Smart contracts and consensus algorithms enable multiple participants to transact with one another and confirm transactions and ledger records.

Alibaba Cloud BaaS supports three types of blockchains: public blockchains, private blockchains, and consortium blockchains. Supported frameworks include Ethereum, EOS, Hyperledger Fabric, and Corda.

Smart contract

A smart contract encodes contract terms, transaction conditions, and business logic using cryptography. Smart contracts execute automatically and reconcile in real time — no manual intervention required.

*See also:* Chaincode (the Hyperledger Fabric equivalent of a smart contract), Virtual machine (VM)

Genesis block

The first block in a blockchain.

Account

An account is the basic operational object on a blockchain — the logical representation of a user. Accounts are required to perform transactions. Accounts fall into two types: common accounts and contract accounts.

*See also:* Identity

Application

An application built on the blockchain SDK.

Blockchain ID

The unique identifier of a blockchain, corresponding to a unique physical resource in the underlying layer.

Block height

Block height identifies a block's position in the blockchain and links to all its underlying attributes and transaction records.

Business ID

The unique identifier of a business scenario in which the blockchain is applied — for example, traceability or rental management.

Business time

The timestamp recording when a transaction is generated.

Category

The format of the chained business data for a given transaction.

Certificate

Certificates for Ant Blockchain are issued by a third-party Certificate Authority (CA) working with Alipay, upon certificate application requests.

*See also:* Certificate Signing Request (CSR), Private key

Certificate Signing Request (CSR)

A CSR file is the public key component generated by tools such as OpenSSL. During key generation, OpenSSL produces two outputs: the CSR file (public key) and a user private key. Store the private key and its corresponding password securely.

*See also:* Private key

Consensus algorithm

A consensus algorithm ensures data consistency in a distributed ledger and keeps transactions synchronized across the network through protocol interactions. Common algorithms include PBFT, RAFT, PoW, and PoS.

In Alibaba Cloud BaaS: Ant Blockchain uses PBFT and RAFT; Quorum supports Istanbul BFT and RAFT.

*See also:* Consensus proof

Consensus proof

A data structure that proves the target data's consistency has been confirmed by the consensus algorithm.

Consortium

A group of organizations working together to complete a specific business objective.

*See also:* Organization (Ant Blockchain)

Decentralized application (DApp)

A DApp connects directly to blockchain nodes through clients and accesses data via smart contracts. Unlike traditional centralized applications, a DApp has no centralized backend services.

Digital envelope

A secure electronic data container that protects a message through encryption and data authentication. Only authorized users can decrypt its contents.

*See also:* Private transaction (Ant Blockchain), Envelope transaction

Envelope transaction

A transaction type that encapsulates a private transaction. When sent, the private transaction is encoded and stored in the data field of the envelope transaction. The envelope transaction itself is stored on the public blockchain as a notary record; the data field can be modified based on business needs.

*See also:* Private transaction (Ant Blockchain)

Gas

The unit for measuring the computational and storage resources required to perform actions in a virtual machine. Gas prevents malicious attacks and limits resource consumption.

*See also:* Virtual machine (VM)

Identity

A 256-byte value that uniquely identifies an account or smart contract, typically represented as a unique, human-readable hash.

Intel Software Guard Extensions (Intel SGX)

An extended instruction set on Intel CPUs that lets applications create private regions (enclaves) to protect code and data. Intel SGX ensures the integrity and confidentiality of security-sensitive computations even when all privileged software is potentially malicious.

*See also:* Trusted Execution Environment (TEE)

Ledger data

Data written into a blockchain. Because a blockchain is a tamper-resistant ledger, data written to it cannot be modified and can therefore be trusted. Ledger data can be a string or a file hash, representing text, files, or other data types.

Node information

Information about the blockchain nodes that make up a network. A blockchain typically consists of multiple nodes. The required number of nodes is 3F+1, where F is a positive integer.

Organization (Ant Blockchain)

An organization is a member of a consortium.

*See also:* Consortium

Previous block hash

The hash of the preceding block, used to chain blocks together and preserve immutability.

Private key

A private key file generated by tools such as OpenSSL. During key generation, OpenSSL produces two outputs: a CSR file (public key) and the user private key. Store the private key and its corresponding password securely.

*See also:* Certificate Signing Request (CSR)

Private transaction (Ant Blockchain)

Unlike ordinary transactions, private transactions are not executed or stored on the public blockchain. Instead, they are encapsulated in the data field of an envelope transaction and ultimately stored on the private blockchain.

*See also:* Envelope transaction

Root hash

The root hash of the Merkle tree, calculated from the current blockchain transaction. Also referred to as the Merkle root.

Transaction

The total number of transactions saved on the current blockchain ledger.

Transaction count

The number of transactions included in a block.

Transaction receipt

The execution result of a transaction. Because a blockchain is an asynchronous network, a consensus protocol must confirm a transaction after it executes. Unlike traditional architectures, a blockchain cannot return a transaction result directly — check the final result in the transaction receipt.

Transaction type

The classification of a transaction. Types include: link notary, content notary, hash notary, ciphertext notary, privacy sharing notary, and ciphertext-only notary.

Trusted Execution Environment (TEE)

A hardware-level isolated environment that provides isolation and trust metrics. TEE technology — best represented by Intel SGX — has seen growing adoption in server and terminal applications.

*See also:* Intel Software Guard Extensions (Intel SGX)

Virtual machine (VM)

The sandbox environment in which smart contracts are executed.

*See also:* Gas

World state

The storage status of all blockchain accounts, including the basic storage of all accounts and the internal storage of contract accounts. The contract platform functions as a transaction-based state machine. The world state holds the latest value for all data in the ledger and updates frequently as smart contracts execute.

Anchor peer

The entry point for peers from other organizations on the same channel to communicate with peers in the anchor peer's organization. Anchor peers ensure high availability and keep the entire network in a synchronized state.

CA

The Certificate Authority (CA) is an entity that issues digital certificates. In Alibaba Cloud BaaS, the CA provides blockchain user registration and enrollment services for an organization.

*See also:* Organization (Hyperledger Fabric)

Chaincode

Code written in a supported language — Node.js, Go, or Java — that implements the business logic of a blockchain network. In Hyperledger Fabric, chaincodes are the smart contracts that run on peers and create transactions.

*See also:* Smart contract, Peer node

Channel

A channel isolates a specific business within a consortium. Each channel represents one business and contains a subset (or all) of the consortium's organizations. One consortium can have multiple channels; one organization can join multiple channels. Each channel functions as a sub-chain with its own ledger, and chaincodes can be deployed to it.

*See also:* Consortium (Hyperledger Fabric), Chaincode

Consortium (Hyperledger Fabric)

A collection of organizations involved in a blockchain-based business collaboration or transaction network.

In Alibaba Cloud BaaS, each consortium has a consortium instance — typically created by the consortium initiator or operator. The consortium instance contains Orderer nodes responsible for transaction sequencing, block generation, and consensus. The consortium operator invites organization instances to join, creates channels, and manages the Orderer nodes.

One blockchain network consists of 1 consortium instance + N organization instances (N ≥ 1). The number of organization instances depends on the number of business participants and whether exclusive access is required. A participant that needs exclusive blockchain nodes, ledger access, chaincode deployment, or user management must create a separate organization instance. Participants without exclusive requirements can share an organization instance. Consortium and organization instances can be purchased and created by a single cloud account or by different cloud accounts.

*See also:* Organization (Hyperledger Fabric), Channel, Orderer node

Orderer node

An ordering service node that sequences and broadcasts transactions. The Orderer collects transactions from network members, orders them, and bundles them into blocks, then delivers the block to all peers to ensure that ledgers are updated with the same transactions in the same order.

*See also:* Peer node

Organization (Hyperledger Fabric)

An entity in the blockchain business network — such as an enterprise, government agency, or group. Each organization instance in Alibaba Cloud BaaS includes the following node types:

• CA: Issues digital certificates and provides blockchain user registration and enrollment services.

• Peer: Receives ordered state updates from the ordering service, maintains the state and ledger, and can act as an endorser.

*See also:* Consortium (Hyperledger Fabric), Peer node, CA

Peer node

A node that maintains a ledger under the Hyperledger Fabric framework. Peers fall into two types:

• Endorsing peer: Executes and endorses transactions. Chaincode must be installed on each endorsing peer to forward endorsement requests.

• Committing peer: Validates transactions and persists accepted blocks to a modular data store. Chaincode installation is not required.

*See also:* Anchor peer, Orderer node

DApp

A distributed application.

*See also:* Decentralized application (DApp) in the Ant Blockchain section.

Enclave

Works with the Transaction Manager to strengthen transaction privacy. The Enclave manages encryption and decryption in isolation, holds private keys, and functions as a virtual hardware security module (HSM) isolated from other components.

*See also:* Transaction Manager

Ethereum Virtual Machine (EVM)

The distributed computing environment that runs smart contracts in Quorum. EVM is a core element of the Quorum architecture.

*See also:* Solidity

Gas (Quorum)

A measure of the computing resources consumed by a transaction. Gas consumption increases with the complexity of the transaction executed by an Ethereum node.

Geth

The command-line interface for running a full Ethereum node, implemented in Go.

Network ID

A numeric identifier that represents a specific version of the Ethereum network.

Private transaction (Quorum)

A transaction whose payload is visible only to specified participants. Set the private parameter to the public keys of the intended recipients to restrict visibility to those participants.

*See also:* Transaction Manager, Enclave

Quorum node

A Quorum node is based on Geth with the following modifications made by Ant Blockchain:

• Supports Istanbul BFT and RAFT consensus algorithms.

• Modified P2P layer to allow connections to or from permissioned nodes only.

• Added block verification logic for private transactions.

• Retained the Gas mechanism but removed the Gas price.

*See also:* Geth, Private transaction (Quorum)

Solidity

An object-oriented, high-level language for writing smart contracts. Solidity is similar to JavaScript and compiles to EVM bytecode.

*See also:* Ethereum Virtual Machine (EVM)

Transaction Manager

Responsible for transaction privacy in Quorum. The Transaction Manager stores encrypted payloads, controls access to encrypted transaction data, and exchanges encrypted payloads with other participants' Transaction Managers. It does not hold any private keys — instead, it calls its associated Enclave to handle encryption. The Transaction Manager is stateless and RESTful, making it straightforward to load balance.

*See also:* Enclave, Private transaction (Quorum)