Blockchain in IoT and Beyond: Case Studies …

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Fig. 8 Ledgers in HI

Fig. 9 Consensus in HI

Credentials

An undeniable credential gives a standard method to carefully communicate qualifi-

cations in a manner that is cryptographically secure, privacy respecting. An element

called an issuer produces and signs such accreditations with its private key. A veri-

fier can look into the public key of a given DID, related to a given certification on a

certain information library.