Ether.fi makes Optimum’s mump2p mandatory for all its node operators

Ether.fi has turned a nice-to-have into a must-have. The liquid staking protocol now requires all 12 of its node operators to run mump2p, a networking tool built by startup Optimum.

Until now, using the software was optional for Ether.fi operators. The change came alongside Optimum’s mainnet launch of the protocol on October 20, 2026.

With that move, 16 Ethereum node operators are now running mump2p in production. Together they manage over 1.4 million staked ETH and approximately 22,000 validator keys.

What mump2p actually does

Every Ethereum block has to travel across a global network of computers before validators can vote on it. Today, that job falls largely to GossipSub, Ethereum’s existing propagation protocol. Optimum says mump2p delivers blocks 2.5 to 3.5 times faster than GossipSub. The company also claims lower timing variance and says up to 90% of blocks get accelerated when routed through its system.

Under the hood, mump2p uses Random Linear Network Coding, or RLNC, layered on top of libp2p. libp2p is the networking toolkit that Ethereum clients already use to talk to each other.

RLNC is easier to picture than to pronounce. Rather than shipping a file in rigid sequential pieces, the network sends mixed combinations of data. A receiver can rebuild the original once it collects enough of those combinations, regardless of which ones arrive first.

The software runs as a sidecar gateway. It sits next to an operator’s existing setup rather than replacing it.

Why staking operators care

According to Optimum, faster propagation improves head-vote accuracy. In plain terms, validators are more likely to vote for the correct, most recent block, and that is what earns rewards.

The company also points to better opportunities to capture MEV. That term describes extra value validators can earn depending on which transactions make it into a block and in what order.

Optimum claims its technology has boosted total value by more than $3.7 billion. That figure comes from the company itself and is best read as a marketing headline rather than an independently audited number.

Optimum says deployment requires no hardware changes and no alterations to Ethereum’s consensus rules. Integration typically takes less than two hours of engineering work per operator.

From testnet to mainnet

Optimum is led by MIT professor Muriel Médard. The mump2p rollout followed an extended testing phase that started in mid-2025 and ran until the mainnet launch.

Beyond Ether.fi’s operators, the user list includes established infrastructure names such as Blockdaemon and Stakefish.

What this means for Ethereum staking

When a large liquid staking protocol makes a tool compulsory for its whole operator set, it stops being a performance experiment. It becomes part of the baseline infrastructure.

It also raises a question worth watching: concentration. As more operators route traffic through the same third-party gateway, the network grows more reliant on one company’s software working correctly. The sidecar design means operators keep their existing setup underneath.

The 2.5 to 3.5 times speed figures and the $3.7 billion value claim are both self-reported by Optimum. Independent measurement from operators or researchers would help show how much of the advertised improvement holds up across different network conditions.