Notarizing files

The API provides three methods of notarizing files:

  • Notarize a file by uploading it to the notary storage. The file cannot be larger than 1 GiB and your account must have sufficient Notary storage and Notarizations quotas.

    The notary service calculates the SHA-256 hash value of the file contents, creates the file’s notarization certificate that contains the information about the notarization status, and then queues the hash value for writing it to the Ethereum blockchain. The writing of queued hash values is triggered every hour and depends on the Ethereum network status.

    The file is stored in the notary storage and can be easily accessed on the Notarized files tab of the notary console. The certificate is always stored in the notary service, is available to all users, and can be accessed via the notary console, the permanent link, or the API.

  • Notarize a file by sending it to the notary service. The file cannot be larger than 1 GiB and your account must have a sufficient Notarizations quota. The logic is very similar to the method above, with the following exceptions:

    • The file is not uploaded and stored in the notary storage.

    • The notarization certificate cannot be accessed via the notary console.

  • Notarize a file by sending a pre-calculated hash value of its contents to the notary service. Your account must have a sufficient Notarizations quota.

    The notary service creates a notarization certificate for the object containing the hash value, and then queues this value for writing it to the Ethereum blockchain. The writing of queued hash values is triggered every hour and depends on the Ethereum network status. The notarization certificate is always stored in the notary service, is available to all users, and can be accessed via the permanent link or the API.

    This is the fastest and most secure way to notarize files because no file data is transferred over the network and stored in other storage and the hash value can be calculated by using an even more secure hash algorithm than the notary service uses. Also, this method offers the ability to notarize files that are larger than 1 GiB.

It is possible to notarize the same file multiple times. A new notarization certificate and blockchain record will be created every time.

Important

It is not possible to cancel the notarization.