Data stored on blockchains is fully immutable, meaning the data cannot be changed without consensus from the network.
This consensus is achieved by applying a set of rules that allows network nodes to confirm or deny the validity of state on the blockchain, ensuring that everyone has an identical record of data without requiring a centralized entity. When media is hashed and stored on the blockchain, the chain's immutable ledger makes detection of unauthorized tampering simple, as any change to the content produces a new hash.
By using nodes to distribute data, blockchain networks eliminate single points of control, decentralizing the system. Each node has a copy of the blockchain, and if the node's copy is tampered with, most nodes will reject it. Decentralization makes systems significantly more difficult to breach or disrupt, enhancing the threat detection process.
All public blockchains offer a transparent history of transactions. This open visibility enables users to verify the origin of all previous transactions and media files on the distributed system, making it easier to distinguish genuine content from deepfakes.
The cryptographic security techniques of blockchain - encryption, digital signatures, and key management - make it an ideal system to store and transfer media and content. Encryption uses complex algorithms to protect media that interacts with the chain, allowing users to verify the authenticity of media. The use of digital signatures allows users to confirm that the media was uploaded by a trusted source, as that source must digitally sign off on the public release of the media file. Private keys, managed by hardware modules or digital multi-signature wallets, are used to verify content and sign off on its release. These security techniques make it nearly impossible to deploy deepfake content without clear evidence of media tampering.
Institutional efforts are underway to ensure the provenance of media and data with the use of blockchains. Microsoft and the BBC have teamed up to launch Project Origin, an initiative that utilizes the technology to combat deepfakes and the spread of misinformation. This cross industry approach leverages decentralization for the authentication of content. The New York Times launched its own internal project to mitigate these threats with the use of distributed ledger technology. The project provides transparent metadata for content, enabling consumers to validate the source of information and identify if any alterations have been made.