Odaily Planet Daily reports that a16z Crypto has published a post exploring the fundamental tension between blockchain "censorship resistance" and "low latency," noting that any Byzantine fault-tolerant (BFT) blockchain protocol with censorship resistance requires at least five communication rounds for optimal good-case latency when more than one-fifth of validators may be malicious, whereas traditional BFT consensus requires as few as three rounds.
The article points out that in traditional BFT protocols, the block proposer holds both the power to construct blocks and to advance consensus, enabling them to censor specific transactions—a root cause of many MEV issues. To address this, Ethereum is researching FOCIL/EIP-7805, while Solana is exploring mechanisms such as Constellation and MCP, all of which center on having validators pre-collect inclusion lists of transactions that cannot be ignored before a block is formally proposed.
a16z Crypto states that achieving censorship resistance requires two additional rounds of communication: first, the user’s transaction must be broadcast to all validators, and then validators must confirm and include it in the inclusion list before the consensus process can begin. Therefore, in a partially synchronous network environment, there is no protocol design that can achieve both BFT and censorship resistance in only four rounds—five rounds are the mathematical lower bound.
The article emphasizes that while censorship-resistant mechanisms increase protocol latency, they significantly reduce the "effective latency" users actually experience. In systems without censorship resistance, transactions may be indefinitely delayed due to validator censorship; in contrast, in systems with censorship-resistant guarantees, transactions are guaranteed to be included in a block within at most five rounds of communication, making transaction confirmation times more predictable.