Reading from Blockchain

• Not all blockchain nodes keep all records that are written to the blockchain. These nodes may return "not found" for records they have purged from their local data. Use a blockchain node that stores the records.

• When GET location status provides a confirmation of your record being submitted to the blockchain, it supplies the Merkle proof:

  • This is a mathematical proof that your record was written to the blockchain at a particular place

  • According to this standard: https://tsc.bsvblockchain.org/standards/merkle-proof-standardised-format/

  • See the example in GET location status

  • Occasionally, the Merkle proof may change over an hour or so, if the blockchain "forks" – this is normal blockchain behaviour, however one prong of the fork will soon become dominant as consensus is restored

• When your record has been confirmed on the blockchain for at least an hour, the Merkle proof will cease being liable to change and, depending on your use case, you can store it as definitive evidence of the blockchain operation.

• You can read your written records from the blockchain at the returned location using a third-party tool. *

• You can also verify your written records at the returned location using a third-party tool. You will need the original record. *

Note: * You will need to trim off the nChain Event metadata from the transaction output to obtain the record. You can try writing an unencoded test record such as "[test]" to identify where the record resides amongst the transaction output.