Blockchain Security
While blockchain is very efficient with respect to transactions, there are concerns about the security of blockchain-distributed ledger technology-based transactions. Vulnerabilities also exist in smart contracts based on some blockchain-based technologies. Some of the issues discovered are that blockchain-based distributed ledger technologies can be hacked like any other IT platform or protocol. If someone chooses to save their private keys on an Internet-connected device, they can be stolen. Once private keys are stolen, it does not matter how secure the blockchain architecture and encryption features are for hackers. Incidents like this have occurred in the past, e.g., the Ethereum attack in June 2016 in which the US $150 million was lost.