PANews reported on March 3rd that, according to The Block, Vitalik Buterin published an article discussing the centralized risks and solutions of Ethereum's "block building pipeline." The upcoming Glamsterdam upgrade plans to introduce a "built-in proposer-builder separation" mechanism, allowing proposers to outsource block building to permissionless markets to prevent staking centralization. However, Buterin points out that ePBS itself could lead to centralized block building, as a few participants capable of optimizing transaction ordering could dominate block building, prompting stakers to join large mining pools associated with them to maximize their profits.
To address this, Buterin proposed extending the upcoming FOCIL mechanism to "Big FOCIL," enabling it to handle all transactions within a block and reducing the block-building role to solely handle MEV-related transactions and state calculations, thus commoditizing it. Furthermore, he proposed introducing a cryptographic mempool to encrypt transactions until they are included in the block, preventing "harmful MEVs" such as sandwich attacks and front-running. Buterin also emphasized that transactions should include anonymization protection from the moment they are sent by the user to the "transaction entry layer" that is packaged into the block. Network layer anonymization tools such as Tor and Flashnet already exist, and the Ethereum Foundation's Kohaku privacy initiative is also interested in this.


