Semiprivate blockchains

With semiprivate blockchains, part of the blockchain is private and part of it is public. Note that this is still just a concept today, and no real world POCs have yet been developed. With a semi-private blockchain, the private part is controlled by a group of individuals, while the public part is open for participation by anyone.

This hybrid model can be used in scenarios where the private part of the blockchain remains internal and shared among known participants, while the public part of the blockchain can still be used by anyone, optionally allowing mining to secure the blockchain. This way, the blockchain as a whole can be secured using PoW, thus providing consistency and validity for both the private and public parts. This type of blockchain can also be called a semi-decentralized model, where it is controlled by a single entity but still allows for multiple users to join the network by following appropriate procedures.