When sensitive data is distributed, an integrity validation system is needed to ensure inmutability. Software distributors usually provide checksums for its application releases. These checksums can be recomputed with the file in posession. If both checksums are identical, the obtained file can be concluded to be an exact copy of the original one. This approach can be extended to other domains where verification is required.
Verifying the integrity of an engraved file is as simple as obtaining a cryptographic digest of the obtained file and query the Engraved Integrity contract. If a record is present, information about the file will be showed. The use of the Ethereum blockchain provides a reliable and highly available storage.
Authors can create namespaces that will be associated with their Ethereum address. Under a given namespace, the owner can add new files with its checksums. For example, this article could be registered as:
Where “engraved’’ is the namespace owned by the Engraved Team.
Besides being sure a file has not been modified while making a copy of it, it is also important to ensure that the file poster is a trustworthy source. In this way, the user could verify that the given file has not been modified and re-registered. For this purpose, a memorable code is assigned to every registered entity. This registration is done when the correspondent registry function is executed from an Ethereum address. This address will be the master address of the entity and will be able to attribute engraving permissions to third addresses under its namespace. One address can be part of multiple entities and thus, when engraving a document, the user will select the corresponding entity. When registering an entity, an identification code, as previously said, is assigned to it. This code could be published by the entity on their official website so users can verify files supposedly published by them. Optionally, the entity could set a DNS TXT record entry so automated verifications of the source domain could be performed with software based on the Engraved system.