a16z Crypto Analyzes Blockchain Censorship Resistance and Latency Trade-offs

a16z Crypto has published an analysis discussing the fundamental conflict between censorship resistance and low latency in blockchain technology. According to Odaily, the article highlights that any Byzantine Fault Tolerant (BFT) blockchain protocol with censorship resistance requires at least five rounds of communication if more than one-fifth of validators are potentially malicious, compared to the minimum of three rounds needed in traditional BFT consensus. The article explains that in traditional BFT protocols, block proposers have the power to both construct blocks and advance consensus, allowing them to censor specific transactions, which is a root cause of many MEV issues. To address this, Ethereum is exploring FOCIL / EIP-7805, while Solana is investigating mechanisms like Constellation and MCP. These approaches focus on validators collecting non-negligible transaction "Inclusion Lists" before formally proposing blocks. a16z Crypto notes that achieving censorship resistance requires two additional communication rounds: first, user transactions must be broadcast to all validators, and then validators must confirm and write them into the inclusion list before the consensus process can begin. In a partially synchronous network environment, no protocol design can achieve both BFT and censorship resistance in just four rounds; five rounds is the theoretical minimum. The article emphasizes that while censorship resistance mechanisms increase protocol latency, they significantly reduce the "effective latency" faced by users. In systems lacking censorship resistance, transactions may be indefinitely delayed by validator censorship. In contrast, systems with censorship guarantees ensure that transactions are included in a block within five communication rounds, making transaction confirmation times more predictable.