Anonymous Communications over Blockchain Technology

A blockchain-based system provides anonymity if it preserves identity privacy and transaction privacy while allowing the users to verify the transactions’ data in order to update the system (Feng et al., 2019). Identity privacy is the concealment of the real-world identities, as well as the transactional relationships, of the involved parties (i.e., senders and receivers) mainly through the use of cryptographic pseudonyms. Transaction privacy is the protection of the transaction’s content against unauthorized access, i.e., the sensitive content (e.g., electronic health records) is only visible to its senders and recipients.