flâneur

Protocol in a Nutshell | Simplex Consensus

simplex.blog · 4,400 words · saved by 1 readers

Consensus. (Also known as State Machine Replication, or the Permissioned Blockchain problem.1) We want a protocol that works as follows: For scalability, players typically batch transactions together into “blocks”. The log is then comprised of blocks, instead of individual transactions, hence the name “blockchain”. It is then easy to extract an ordered log of transactions from a blockchain. The Partially Synchronous network setting. In a real-world network, such as the internet, messages may sometimes be delayed, reordered, or dropped entirely. Entire partitions of the network may lose connectivity due to an implementation bug, or an internet outage. It is essential to prevent a consistency violation (e.g. a double spend) in such a situation. We assume a network that behaves as follows:2 We require the protocol to confirm transactions under good network conditions, and to preserve consistency even under bad network conditions.3 Why is this problem hard? The challenge of faulty players.

Protocol in a Nutshell # What is Consensus? # Consensus. (Also known as State Machine Replication , or the Permissioned Blockchain problem . 1 ) We want a protocol that works as follows: Setup. There are \(n\) players, \(f\) of whom are faulty . Here, we assume that \(f < n/3\) , and that each of these faulty players are malicious (syn: Byzantine ), and can deviate arbitrarily from the protocol. (Of course, one may not need to be so pessimistic about faulty behavior - see Simplex for Crash Faults .) Transactions. Over time, players receive transactions \(\mathsf{txs}\) from the environment, an

related reading