Ethereum Developers Address Potential Glitch Ahead of the Merge

The chance of an MEV-Boost failure is slim, but contingencies should ensure that the Merge still happens smoothly.

AccessTimeIconAug 2, 2022 at 8:49 p.m. UTC
Updated Apr 10, 2024 at 2:26 a.m. UTC
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During Ethereum’s 92nd Consensus Layer Call, developers discussed some solutions to a potential wrinkle in the smooth execution of the network’s impending Merge, when Ethereum moves from its current proof-of-work (PoW) protocol to the Beacon Chain proof-of-stake (PoS) blockchain.

Alex Stokes, a researcher at the Ethereum Foundation, raised concerns over a possible MEV-Boost failure. The vulnerability could affect the way that relay operators, which are intermediaries between block builders and validators, communicate with each other. As a result, the orderly addition of blocks to the blockchain could be disrupted.

However, Stokes told CoinDesk that this complication should have no effect on the timeline of the Merge.

What is MEV-Boost?

MEV-Boost is an important component of “maximal extractible value” (MEV) for Ethereum. MEV refers to the income that miners (under PoW) and block builders and validators (under PoS) receive as a result of inserting or reordering of transactions within a block.

MEV-Boost, which is designed to avoid MEV centralization, is a middleware component that allows validators to request blocks from a network of builders. After the Merge, those interacting with the network will send their transactions over the blockchain to block builders. The MEV-Boost feature will then collect these blocks and offer them to validators. Validators will select and propose the most profitable blocks to the Ethereum network.

If there is a malfunction in MEV-Boost, it will disrupt the entire PoS blockchain. A glitch with a relay operator could fail to release a block at the right moment. Then a series of blocks from validators running MEV-Boost would be missed. That would happen if the validator fails to propose a block because of a relay that didn’t have a way of signaling malicious behavior to validators.

The next set of validators could then be compromised, and if they were to propose a block that has dealt with the malicious relay, the same issues would continue on, preventing the production of blocks indefinitely.

Options on the table

During the call, one proposal addressed the possibility of introducing a circuit breaker. This could be as simple as writing code that tells the validator to automatically turn off if there are missed blocks. This would be a risky move because validators could deliberately withhold blocks from being proposed. There is incentive to do that, and by duping other validators, the person could monopolize MEV earnings.

Other developers also suggested that a third-party dashboard could watch over the relays. The Flashbots team, the developers behind MEV-Boost, are already working to create some kind of public monitoring system for MEV-activity. Ben Edgington, the lead product owner for Teku at ConsenSys, who is involved in the Merge development, told CoinDesk that there are several options for achieving the right solution for the MEV-Boost issue. “It’s just a question of choosing a good approach,” he said.

Christine Kim, a research associate at Galaxy Digital who took notes on the meeting, said that “MEV-Boost already does place inherent trust in relay operators. The trust in relay operators for earning MEV has always been known but what wasn’t known before Thursday’s call was the ability of a relay operator to potentially cause network downtime in this process.”

After the call, Stokes told CoinDesk that developers are exploring options that would have users wait for the Merge to be completed before attempting to use the builder, or to introduce some kind of circuit breaker. Stokes said that the chances of an MEV-Boost failure are very low, but he is pushing to get some kind of solution implemented in the event that it does happen.


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Margaux Nijkerk

Margaux Nijkerk reports on the Ethereum protocol and L2s. A graduate of Johns Hopkins and Emory universities, she has a masters in International Affairs & Economics. She holds a small amount of ETH and other altcoins.

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