Comment by betwixthewires
4 years ago
Keys are identities. Someone claiming to be you doesn't matter. Always defer to keys.
A non public ledger would be something agreed upon by participants only. So you and I and 5 other people for example could run some type of organization using some private way to keep track of state. You choose to trust it, if you don't, then don't use it.
If it doesn’t need a public ledger, why do you need a blockchain in the first place?
It doesn't have to be a blockchain. All these people selling "blockchain" are selling hype, the only reason you need a blockchain is if you're in an adversarial, permissionless environment and need consensus on state, and possibly need a record of historical state.
In a private system, you just need consensus among participants, potentially in an adversarial environment, but decidedly not a permissionless environment. As long as state can be kept, depending on the constraints of the system any sort of consensus and canonical state keeping mechanism would work. Could be a blockchain or something resembling one, could just be a document and it's hash kept by all participants and updated when the participants agree to a change. How complex you make consensus in a permissioned system depends on the goals and constraints of the system.