Logical clock mechanism proposed by Leslie Lamport (1978) for ordering events in distributed systems without synchronized physical clocks. Solana's Proof of History extends this concept by using a SHA-256 hash chain as a verifiable, cryptographic logical clock, creating a global ordering of events without requiring validators to communicate timestamps.
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Logical clock mechanism proposed by Leslie Lamport (1978) for ordering events in distributed systems without synchronized physical clocks. Solana's Proof of History extends this concept by using a SHA-256 hash chain as a verifiable, cryptographic logical clock, creating a global ordering of events without requiring validators to communicate timestamps.
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Lamport Timestamp (lamport-timestamp) Category: Programming Fundamentals Definition: Logical clock mechanism proposed by Leslie Lamport (1978) for ordering events in distributed systems without synchronized physical clocks. Solana's Proof of History extends this concept by using a SHA-256 hash chain as a verifiable, cryptographic logical clock, creating a global ordering of events without requiring validators to communicate timestamps. Aliases: Logical Clock Related: Proof of History (PoH), SHA-256 Hash Chain, Consensus Mechanism
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A clock mechanism that cryptographically proves the passage of time between events. PoH uses a sequential SHA-256 hash chain where each output becomes the next input, creating a verifiable ordering of events without requiring consensus. The leader produces ~400,000 hashes per slot (~400ms), and any validator can verify the sequence in parallel, enabling Solana's high throughput by removing the need for validators to agree on time.
The core mechanism of Proof of History. A SHA-256 hash is computed sequentially—each hash takes the previous hash as input—creating an ordered, unforgeable timestamp sequence. The PoH generator runs approximately 400,000 hashes per slot. Data (transactions) can be inserted into the chain by mixing their hash with the current state.
The protocol by which nodes in a distributed network agree on the current state of the ledger. Common mechanisms include Proof of Work (Bitcoin), Proof of Stake (Ethereum, Solana), and BFT variants. Consensus ensures all honest nodes converge on the same transaction history despite potential network delays or malicious actors.
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A clock mechanism that cryptographically proves the passage of time between events. PoH uses a sequential SHA-256 hash chain where each output becomes the next input, creating a verifiable ordering of events without requiring consensus. The leader produces ~400,000 hashes per slot (~400ms), and any validator can verify the sequence in parallel, enabling Solana's high throughput by removing the need for validators to agree on time.
The core mechanism of Proof of History. A SHA-256 hash is computed sequentially—each hash takes the previous hash as input—creating an ordered, unforgeable timestamp sequence. The PoH generator runs approximately 400,000 hashes per slot. Data (transactions) can be inserted into the chain by mixing their hash with the current state.
The protocol by which nodes in a distributed network agree on the current state of the ledger. Common mechanisms include Proof of Work (Bitcoin), Proof of Stake (Ethereum, Solana), and BFT variants. Consensus ensures all honest nodes converge on the same transaction history despite potential network delays or malicious actors.
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A systems programming language emphasizing memory safety, zero-cost abstractions, and concurrency without a garbage collector. Rust uses an ownership model with borrow checking at compile time to prevent data races and null pointer bugs. It is the primary language for Solana program development (via Anchor or native solana-program crate) and the Agave validator client.
A statically typed superset of JavaScript that compiles to plain JavaScript. TypeScript adds type annotations, interfaces, generics, and enums to catch errors at compile time. It is the standard language for Solana client-side development—wallet adapters, dApp frontends, test suites, and SDK interactions (web3.js, Anchor client) are typically written in TypeScript.
The ubiquitous scripting language for web development, running in browsers and Node.js. JavaScript is dynamically typed and event-driven. Most Solana dApp frontends and scripts use JavaScript/TypeScript with libraries like @solana/web3.js. Node.js enables server-side JS for backend services, indexers, and bot development.
A JavaScript runtime built on Chrome's V8 engine that enables server-side JavaScript execution. Node.js uses an event-driven, non-blocking I/O model. In the Solana ecosystem, Node.js is used for: running Anchor tests (Mocha/Jest), backend services, transaction bots, indexers, and CLI tools. npm/yarn/pnpm manage JavaScript package dependencies.