Practical Byzantine Fault Tolerance is actually a consensus algorithm introduced from the late 90s by Barbara Liskov and Miguel Castro. pBFT was designed to work competently in asynchronous(no higher certain on when the response to the request will be obtained) units. It can be optimized for low overhead time. https://financefeeds.com/bitcoin-and-ethereum-build-momentum-as-institutional-inflows-regulatory-clarity-drive-bullish-sentiment/