I have been following the three-year-old Hyperledger Fabric open-source project since its code base moved to GitHub about two years ago. The Hyperledger projects are hosted by the Linux Foundation and sponsored mostly by IBM. They promote the use of what are known as private, or permissioned, blockchains. With a public blockchain, the first anonymous miner who solves a cryptographic puzzle gets to commit the next block of ledger entries to the chain. Private blockchains solve the consensus problem among authenticated peers using algorithms such as Raft or Paxos.
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