A modified fork of the Agave validator client maintained by Jito Labs that adds an out-of-protocol block space auction. Jito's modifications include a block engine that accepts transaction bundles with tips, enabling MEV extraction while returning value to stakers. The majority of mainnet-beta stake runs the Jito client.
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A modified fork of the Agave validator client maintained by Jito Labs that adds an out-of-protocol block space auction. Jito's modifications include a block engine that accepts transaction bundles with tips, enabling MEV extraction while returning value to stakers. The majority of mainnet-beta stake runs the Jito client.
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Consensus, leader rotation, slots, epochs, and the runtime.
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Jito Validator Client (jito-validator) Category: Core Protocol Definition: A modified fork of the Agave validator client maintained by Jito Labs that adds an out-of-protocol block space auction. Jito's modifications include a block engine that accepts transaction bundles with tips, enabling MEV extraction while returning value to stakers. The majority of mainnet-beta stake runs the Jito client. Aliases: Jito-Solana Related: Agave, Validator, MEV (Maximal Extractable Value)
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The Rust-based Solana validator client maintained by Anza (formerly Solana Labs). Agave is the original and most widely deployed validator implementation. It handles all aspects of validation: TPU, TVU, gossip, AccountsDB, and RPC. The name 'Agave' was adopted to distinguish it from the Firedancer client.
A node that participates in the Solana network by validating transactions, voting on blocks, and (when selected as leader) producing new blocks. Validators run the Agave, Firedancer, or Jito client software, require significant hardware (128+ GB RAM, high-core CPU, NVMe SSD), and earn rewards from inflation and transaction fees.
The profit a block producer (leader) or sophisticated trader can extract by controlling the ordering, inclusion, or exclusion of transactions within a block — including strategies like front-running, back-running, sandwich attacks, and arbitrage. On Solana, MEV dynamics differ from Ethereum because there is no public mempool; transactions are forwarded directly to the current leader, making latency and validator relationships central to MEV capture. The Jito infrastructure provides the dominant MEV marketplace on Solana through bundles and tips.
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A node that participates in the Solana network by validating transactions, voting on blocks, and (when selected as leader) producing new blocks. Validators run the Agave, Firedancer, or Jito client software, require significant hardware (128+ GB RAM, high-core CPU, NVMe SSD), and earn rewards from inflation and transaction fees.
The first validator in a Solana cluster that produces the genesis block and bootstraps the initial ledger. The bootstrap validator generates the genesis configuration, creates the initial accounts (mint, vote, stake), and begins producing PoH entries and blocks. Other validators then join the cluster by connecting to the bootstrap validator via gossip and downloading a snapshot.
A formal specification document describing proposed and accepted changes to the Solana protocol, analogous to Ethereum's EIPs. SIMDs are categorized as Standard (Core, Networking, Interface) or Meta, and require supermajority validator stake-weighted voting (66.67%) to pass. Notable SIMDs include SIMD-33 (Timely Vote Credits), SIMD-123 (Block Revenue Sharing), SIMD-228 (Market-Based Emissions), and SIMD-326 (Alpenglow).
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The Rust-based Solana validator client maintained by Anza (formerly Solana Labs). Agave is the original and most widely deployed validator implementation. It handles all aspects of validation: TPU, TVU, gossip, AccountsDB, and RPC. The name 'Agave' was adopted to distinguish it from the Firedancer client.
A node that participates in the Solana network by validating transactions, voting on blocks, and (when selected as leader) producing new blocks. Validators run the Agave, Firedancer, or Jito client software, require significant hardware (128+ GB RAM, high-core CPU, NVMe SSD), and earn rewards from inflation and transaction fees.
The profit a block producer (leader) or sophisticated trader can extract by controlling the ordering, inclusion, or exclusion of transactions within a block — including strategies like front-running, back-running, sandwich attacks, and arbitrage. On Solana, MEV dynamics differ from Ethereum because there is no public mempool; transactions are forwarded directly to the current leader, making latency and validator relationships central to MEV capture. The Jito infrastructure provides the dominant MEV marketplace on Solana through bundles and tips.
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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.
Solana's custom BFT consensus algorithm built on top of Proof of History. Tower BFT uses PoH as a clock to reduce communication overhead in traditional PBFT from O(n²) to O(n). Validators vote on forks with exponentially increasing lockout periods—each consecutive vote doubles the lockout, making rollbacks progressively more expensive. A fork is finalized when it reaches supermajority (66.7%+ of stake).
A time window during which a designated leader validator can produce a block. Each slot lasts approximately 400 milliseconds. Slots are numbered sequentially from genesis and grouped into epochs of 432,000 slots (~2-3 days). Not every slot produces a block—a skipped slot means the leader was offline or too slow.
A set of entries produced by a leader during a single slot. A block contains transactions bundled into entries, each with a PoH hash proving ordering. Blocks are broken into shreds for network propagation via Turbine. Maximum block size is limited by compute units (48M CU cap per block) rather than byte size.