Distributed Ledger Technologies (DLTs), when managed by a few trusted
validators, require most but not all of the machinery available in public DLTs.
In this work, we explore one possible way to profit from this state of affairs.
We devise a combination of a modified Practical Byzantine Fault Tolerant (PBFT)
protocol and a revised Flexible Round-Optimized Schnorr Threshold Signatures
(FROST) scheme, and then we inject the resulting proof-of-authority consensus
algorithm into Bitcoin (chosen for the reliability, openness, and liveliness it
brings in), replacing its PoW machinery. The combined protocol may operate as a
modern, safe foundation for digital payment systems and Central Bank Digital
Currencies (CBDC)
