In this third post, we conclude with the celebrated Fischer, Lynch, and Paterson impossibility result from 1985. It is the fundamental lower bound for consensus in the asynchronous model. Theorem 1 (FLP85): Any protocol $\mathcal{P}$ solving consensus in the asynchronous model that is resilient to even just one crash failure...| decentralizedthoughts.github.io
Post updated in March 2021 Different modeling assumptions under which we construct BFT protocols often make it hard to compare two protocols and understand their relative contributions. In this post we discuss synchronous protocols in the authenticated model (assuming a PKI). A protocol runs in the synchronous model if it...| decentralizedthoughts.github.io
In this series of three posts, we discuss two of the most important consensus lower bounds: Lamport, Fischer [1982]: any protocol solving consensus in the synchronous model that is resilient to $t$ crash failures must have an execution with at least $t+1$ rounds. Fischer, Lynch, and Patterson [1983, 1985]: any...| decentralizedthoughts.github.io