Traceability of payment transactions (e.g., Bitcoin)
Traceability of identities (e.g., Civic)
Extreme anonymization of transactions (e.g., ZCash, Monero)
File storage (e.g., Filecoin, Storj, Via, Holo)
Interoperability of existing information systems at the international level (e.g., Ripple for finance)
Scalability and performance of consensus (e.g., BitcoinCash, EOS)
Mining algorithms (e.g., Verge)
Trusted third parties (e.g., Hyperledger Fabric, Corda for finance).
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