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.
Overview
An external commitment is Truestamp’s permanent ledger record that one internal block was
committed to one public blockchain. Each record pairs a block with one chain and carries
the compact Merkle proof that ties the block’s block_hash to the
epoch root recorded on that chain; the records are immutable,
publicly readable, and unique per block and chain. In a
proof bundle external commitments appear as the
entries of the commitments array, each naming its chain in plain text (stellar or
bitcoin) and carrying the epoch root, the epoch proof, and the public-chain transaction
reference. Every
bundle must contain at least one, because a bundle with no external commitment would
resolve only to Truestamp’s own signature chain, defeating the promise of verification
without trusting Truestamp. How epochs and their per-block proofs are produced is covered
in the epoch and Block Commitment.