Check it, don't just trust it
Public records
Each thing TallClip records goes on the public ledger within a minute. Every minute that there are new records, they are gathered into one summary that is sealed there too, so nothing in it can be changed afterwards. Back to the pulse ›
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Check it with your own tools
You don't need TallClip's page to check a summary. Here is how it is made:
- Each record is a data output in its own transaction on the public ledger. Its fingerprint (the "leaf") is a double SHA-256 - SHA-256 run twice - of the record's exact bytes. The download above lists every leaf, in order.
- The leaves are paired up and hashed again - double SHA-256 of the left one followed by the right one - and so on up, level by level, into a Merkle tree. When a level has an odd number of items, the last one is paired with itself, as in a block. What is left at the top is the root.
- The summary's transaction has a data output that starts with the letters ACH1, then the root (32 bytes), then how many leaves there are (4 bytes, big-endian), then the batch name (its length, then its text).
- Hash the leaves yourself, rebuild the root, and compare it with the one in the transaction. If they are the same, the records listed are exactly the ones that were sealed - and a single changed or missing record would give a different root. "Check this summary" does exactly this in your browser; the ledger's own site is only asked for the transaction.
- Private records appear only as leaves. Nobody but their owner can read them, but they are in the tree, so they cannot be quietly added or removed either.
The format is the one used by the open AnchorChain project, so its tools can read these summaries too.