Knowledge Base
Browse the concepts behind Truestamp. Follow the links between concepts, or search across everything.
Tagged: commitment
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Blockchain
Item Commitment vs Block Commitment
The load-bearing distinction between Item Commitment (an item's item_hash becomes a Merkle-tree leaf in a finalized block) and Block Commitment (block hashes Merkle-rooted into an epoch whose root is recorded on a public blockchain such as Stellar or Bitcoin), and why a complete proof needs both.
Public Ledger Explorer
The public ledger explorer pages, no account required - the /blocks index and /blocks/<block_id> detail with commitment chain and proof downloads, the /entropy and /entropy/<observation_id> observation pages, and the real-time /timeline visualization of entropy, items, blocks, and commitments.
The Epoch and Block Commitment
How Truestamp batches many finalized internal block hashes into an epoch, builds one epoch Merkle root, records that single root on a public blockchain (Stellar via MEMO_HASH, Bitcoin via OP_RETURN), and gives each block an inclusion proof within the epoch as its Block Commitment.
Glossary
Bitcoin
A public proof-of-work blockchain Truestamp uses two ways, capturing new Bitcoin block hashes as entropy observations and committing epoch roots into a transaction OP_RETURN output, which appears in a proof bundle as a commitments entry with chain bitcoin and a regtest, testnet, or mainnet network.
Block Commitment
The second Truestamp commitment event: finalized block hashes are batched into an epoch whose single Merkle root is recorded on a public blockchain (Stellar MEMO_HASH, Bitcoin OP_RETURN), moving each covered block from finalized to committed and adding an external timing witness.
Commitment
Truestamp's term for recording a hash somewhere durable and checkable: Item Commitment places an item's hash in a finalized block's Merkle tree, Block Commitment records an epoch root of batched block hashes on a public blockchain, and a complete proof requires both events.
Committed
The normal resting state on both Truestamp ledgers - an item is committed once its item hash is a leaf in a finalized block (Item Commitment), and a block is committed once its block hash is covered by an epoch recorded on a public blockchain (Block Commitment).
Epoch
The batch Truestamp uses for Block Commitment: all block hashes finalized since the last commitment of a given kind form one Merkle tree whose single root is recorded on a public blockchain, with each chain (Stellar, Bitcoin) advancing its own independent series of epochs.
Epoch root
The single Merkle root summarizing every block hash in an epoch, the exact value written on-chain as a Stellar transaction memo hash or a Bitcoin OP_RETURN payload, carried in a proof bundle as each commitment's epoch_merkle_root and the root its epoch_proof walks a block hash up to.
External Commitment
Truestamp's permanent per-block, per-chain record that a block was committed to a public blockchain, carrying the Merkle proof from block_hash to the on-chain epoch root; appears in a proof bundle as an entry in the commitments array naming its chain, and every bundle carries at least one.
Item Commitment
The first Truestamp commitment event: an item's item_hash becomes a Merkle-tree leaf in a finalized block, recorded with a compact inclusion proof, moving the item to the committed state and proving it was submitted within that block's submission window.
Stellar
A public blockchain Truestamp uses two ways: Stellar ledger closes are captured as entropy observations, and epoch roots are committed as a transaction MEMO_HASH, appearing in a proof bundle as a commitments entry with chain stellar and a network of testnet or public.
Product
Submission Window
The submission window is Truestamp's honest time guarantee, the cryptographic proof that data was submitted after a set of public records it witnesses and before the block that includes it, which is why we say submitted and submission window rather than created or creation time.
What Truestamp Proves
The affirmative guarantees of a Truestamp proof, that the exact bytes existed unchanged and that submission fell inside a submission window whose earlier edge rests on witness records the proof carries and whose later edge is committed to a public blockchain, every hash re-derivable offline.
Verification
Proof Claims by Availability
Claims matrix for a Truestamp item proof, which of eight claims (bytes existed, unchanged, both submission-window edges, signature, key binding, ledger position, entropy freshness) hold from the bundle alone, from public chains and sources, from a pinned keyring, from the ledger, or never.
The Proof Lifecycle
How a Truestamp proof comes to exist and strengthens over time as an item is submitted against a set of witnesses, committed into a block via item commitment, and that block is committed to Stellar and Bitcoin via block commitment.