Key Terminology

A list of the VMware Blockchain terminology definitions. These terminologies and concepts are commonly used throughout the product documentation.

Authenticated Key-Value Ledger

To prove facts about smart contracts on the platform and to allow, access to a privacy-aware verifiable source of truth, VMware Blockchain stores the state of the blockchain in an authenticated key-value data structure. This data structure is part of the Replica nodes in the Replica network.

The authenticated data structure is implemented as a sparse Merkle tree where the application data keys are the leaves of the tree. Application data keys have metadata that allows the Replica Network to implement privacy controls.

Block

Results of the executed transactions that have been committed to the blockchain ledger.

Blockchain

A data structure that holds a group of records. These groups of records create a block, and these blocks are linked using cryptography.

Each block contains a cryptographic hash of the previous block. The records are saved as a list of keys and their values, which comprise the state of the blockchain.

Client node

Allows sending requests to the Replica Network and receiving the results after running these requests.

BFT protocol

This protocol is the communication between the Replica nodes that allows them to synchronize. The nodes must agree on which requests are executed, the order of execution, and a process to maintain State Machine on all the Replica nodes.

The protocol can tolerate slower Replica nodes than others, disconnected or failing Replica nodes, and even malicious Replica nodes.

DAML

DAML (Digital Asset Modeling Language) is an open-source system for building full-stack smart contract-based distributed applications.

Its core smart contract language is a purpose-built functional language specialized in describing composable distributed business workflows.

DAML Ledger API

DAML smart contracts are stored on a ledger. To exercise choices on those smart contracts, create smart contracts, or read from the DAML Ledger, users use the DAML Ledger API.

Decentralized Applications (DApps)

An application that keeps some or all its state on the blockchain.

Replica Node

Replica nodes store the replicated State Machine. Each Replica node has a local key-value database store, RocksDB, and a DAMLe.

The Replica nodes actively participate in the BFT State Machine Replication protocol.

Replica Network

A network that consists of Replica nodes that use an authenticated key-value storage and a deterministic State Machine to run smart contracts. The Replica nodes use the BFT protocol to create consensus and maintain the same state on all the nodes even if some of the Replica nodes are down or even malicious.

RocksDB

Persistent key-value storage used by the Replica nodes.

Smart Contract Execution Engine (DAMLe)

Interprets the DAML commands and provides results in a key-value format. DAMLe is available in every Replica node in the blockchain.

Smart Contract

An application where the code and state are stored on the blockchain.

Transaction

Request sent from the Client node to the Replica Network to be executed and the results persisted on the ledger.

VMware Blockchain

Distributed trust platform that enables business networks, who might not necessarily trust one another, to share data or transact in a permissioned business network. The VMware Blockchain core natively supports pluggable State Machine Replication atop a BFT replication protocol.

VMware Blockchain only makes assumptions that the network is permissioned. Measures are established to prevent or detect malicious behavior because Replica nodes within a network might have incentives to behave maliciously, or their systems might be compromised.

Overall, VMware Blockchain enables the network to operate correctly even if a subset of Replica nodes behaves dishonestly. These guarantees do not depend on synchrony assumptions of the network and a violation of message delivery deadlines might only result in a momentary lack of progress, not inconsistency, or safety violations.

VMware Blockchain Orchestrator

A standalone virtual appliance (VApp) designed to streamline deployment operations on a private cloud in an on-premises environment. The VApp includes a CLI-based interface to configure the infrastructure and deployment parameters. The defined parameters automate several deployment tasks to simplify the deployment process.