Ethereum’s Ropsten Testnet Successfully Merges

The Ropsten Proof-of-Work testnet has merged with its Proof-of-Stake beacon chain, finalizing one of the last rehearsals before the Ethereum mainnet transition.

Ropsten Testnet Completes Merge

Ethereum’s Ropsten Testnet successfully merged with its beacon chain today, bringing the network one step closer to the highly-anticipated mainnet merge.

The testnet operation, which happened at 16:10 UTC, marks a significant milestone in a long technical process colloquially known in the crypto space as the “Merge.” The Merge will see Ethereum abandon its current Proof-of-Work consensus model in favor of the more energy-efficient Proof-of-Stake. The upgrade is expected among other things to reduce the ETH token emission rate by approximately 90%.

The Ropsten Testnet, created in 2016 and named after a metro station in Stockholm, was notable for being Ethereum’s only Proof-of-Work testnet, and was considered one of the best replications of the Ethereum Mainnet. It had previously launched its own beacon chain on May 30 in preparation for today’s Merge trial run.

Ropsten’s close resemblance to Mainnet allows for developers to conduct realistic tests on it before deploying them on mainnet. The successful evolution of the Ropsten Testnet to a Proof-of-Stake consensus mechanism therefore bodes well for the Ethereum Mainnet’s own forthcoming transition.

However, a few more steps remain before the mainnet Merge. Two more Ethereum testnets, Goerli and Sepolia, will have to undergo their own merges, and the current difficulty bomb may have to be set back. The difficulty bomb exponentially raises the mining difficulty of the Ethereum Proof-of-Work chain in order to incentivize nodes to switch to the post-merge Proof-of-Stake chain. If Ethereum’s developers take too long in preparing for the Merge, they will need to postpone the difficulty bomb to keep the network functioning until the Merge can take place. Developers have already suggested on the Ethereum Improvements Proposals (EIP) forum to postpone the difficulty bomb to mid-August.

Ethereum developer Preston Van Loon has previously stated that the Merge could take place as soon as August, although Ethereum co-founder Vitalik Buterin has also given a more conservative estimate of September or October. After today’s successful Ropsten Testnet merge, the outlook for an August mainnet merge now looks more likely. However, it’s worth noting that previous network upgrades have encountered multiple delays. With the pressure mounting, Ethereum’s developers will be keen to ensure the network’s biggest update to date is executed flawlessly. 

Disclosure: At the time of writing, the author of this piece owned ETH and several other cryptocurrencies.