Network
Launch Date
Consensus
Note
Sepolia
Oct 2021
PoW
Like-for-like representation of Ethereum
Görli
Jan 2019
PoA
Proof-of-Authority
Kiln
Mar 2022
PoS
Post-Merge (for ETH2), shadow fork of the mainnet
Kintsugi
Dec 2021
PoS
DEPRECATED, use Kiln; post-Merge (for ETH2)
Ropsten
Nov 2016
PoW
DEPRECATED, use Sepolia; the Merge to happen on Jun 8, 2022
Rinkeby
Apr 2017
PoA
DEPRECATED, use Görli and Görli Faucet
Kovan
Mar 2017
PoA
DEPRECATED, use Sepolia or Görli
List of active and deprecated Ethereum testnets, including Kintsugi.
Features
Optimistic rollup 
ZK-rollup 
Proof
Uses fraud proofs to prove transaction validity. 
Uses validity (zero-knowledge) proofs to prove transaction validity. 
Capital efficiency
Requires waiting through a 1-week delay (dispute period) before withdrawing funds. 
Users can withdraw funds immediately because validity proofs provide incontrovertible evidence of the authenticity of off-chain transactions. 
Data compression
Publishes full transaction data as calldata to Ethereum Mainnet, which increases rollup costs. 
Doesn't need to publish transaction data on Ethereum because ZK-SNARKs and ZK-STARKs already guarantee the accuracy of the rollup state. 
EVM compatibility
Uses a simulation of the Ethereum Virtual Machine (EVM), which allows it to run arbitrary logic and support smart contracts. 
Doesn't widely support EVM computation, although a few EVM-compatible ZK-rollups have appeared. 
Rollup costs
Reduces costs since it publishes minimal data on Ethereum and doesn't have to post proofs for transactions, except in special circumstances. 
Faces higher overhead from costs involved in generating and verifying proofs for every transaction block. ZK proofs require specialized, expensive hardware to create and have high on-chain verification costs. 
Trust assumptions
Doesn't require a trusted setup. 
Requires a trusted setup to work. 
Liveness requirements
Verifiers are needed to keep tabs on the actual rollup state and the one referenced in the state root to detect fraud. 
Users don't need someone to watch the L2 chain to detect fraud. 
Security properties 
Relies on cryptoeconomic incentives to assure users of rollup security. 
Relies on cryptographic guarantees for security. 
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Ethereum
Merge Overview

Technical Aspects of Ethereum Merge

Definitions, Risks, and How You can Help
Last Updated:
May 7, 2022

The time is coming when Ethereum moves from proof of work to proof of stake. While proof of work is fully reliable and secure, ensuring thousands of nodes will reach a consensus, it comes at a cost. Proof of work requires a lot of computing power to solve complex problems, and because of this, also requires lots of energy.

Proof of stake does not require energy-intensive equipment and still improves efficiency, increases decentralization, and resists censorship. Proof of stake will become the new standard for the entire network. Throughout this article, we’ll explain The Merge and tell you ways you can get involved.

What steps on the Ethereum roadmap are required for The Merge?

Source

Steps required on the Ethereum roadmap to get to The Merge include the addition of the beacon chain, removing the proof of work consensus layer, and merging proof of stake into the Ethereum mainnet.

What is the Beacon Chain?

The Beacon Chain is a fully independent decentralized network running parallel to the Ethereum Mainnet that uses the proof of stake consensus mechanism instead of Ethereum’s current Proof of work consensus mechanism. 

The purpose of the Beacon Chain is to support the transition from proof of work to proof of stake, and it is the first step needed to complete the merge.

The Beacon Chain transition started in November 2020 when a one-way bridge started moving the proof of work chain to the proof of stake chain and started accepting deposits. One month later, the Beacon Chain launched and secured millions of ETH across several validators. So far the Beacon Chain has not experienced any downtime or network interruptions.

What is the Merge?

The Merge is a planned Ethereum network upgrade that removes the proof of work consensus layer and merges the Beacon Chain’s proof of stake network into the current Ethereum mainnet. Ethereum’s consensus mechanism is a contribution to the network following Eth1. Eth1 was known as the execution layer. This will soon be deprecated as we migrate towards Eth2, now renamed The Merge.

Primarily The Merge will focus on the execution of upgrading the consensus mechanism and  bringing it in line with its original mission: to migrate from proof of work to proof of stake, validate transactions on the blockchain, and add new blocks.

Source

What happens to Ethereum’s consensus layer and data layer during The Merge?

During The Merge, the consensus layer is upgraded, and the data layer will remain unchanged. Ethereum’s blockchain data is structured so that it consists of two fundamental elements: a pointer and a linked list.

A linked list is a list of chained blocks that contain data and use pointers that point toward the previous block. Since The Merge is not the launch of a new version of Ethereum but rather an upgrade, the data layer won’t be affected in this process.

Once this transformation is complete, Ethereum will now be at a point of a more sustainable, eco-friendly ecosystem. 

What happens after The Merge?

After The Merge, the Ethereum blockchain will prioritize adding new features planned through a separate upgrade, a post-merge cleanup, and sharding. Some of the planned features include things like allowing stakers to withdraw staked ETH. 

The post-merge "cleanup" upgrade addresses these features, which is expected to happen very soon after The Merge is complete. 

Source

Finally, the process of sharding will be used to further scale Ethereum. Right now, Ethereum can only handle about 15 transactions a second. With sharding, Ethereum will have the capabilities to scale thousands of transactions by splitting the blockchain into “shards” (separate chains).

Sharding is a commonly used Web2 strategy for scaling databases. However, with Ethereum, this will lower the barrier of entry for validators to store and run data and is much more convenient than running the entire blockchain. Running an Ethereum node from your laptop or mobile device would soon be possible thanks to shard chains.

What are the risks of The Merge?

If The Merge fails, it could create a chain reaction that affects other blockchains and ecosystems dependent on Ethereum. 

There is a lot of hope going for the Ethereum merge, but that also comes with risks involved for all Ethereum network participants. 

The Merge has an important role in making changes to a current protocol managing hundreds of billions of dollars in assets. It's been known that The Merge has been delayed a number of times. 

The most recent delay was in June announcing that The Merge won’t happen in June, but a few months after. The Merge is now expected to ship in Q3 or Q4 of 2022.

Ethereum functions as the base layer for thousands of decentralized apps (dApps). Failure of The Merge could affect many dApps, ranging from altcoins like Basic Attention Token (BAT) to Layer 2s like Polygon (MATIC) and metaverse tokens like Sandbox. In addition, NFTs, DAOs, and other encrypted technologies could be affected.

If The Merge fails to meet expectations, Ethereum currently has 4 unique client implementations of proof of stake Ethereum nodes. This means proof of stake node operators can switch to different clients, if one experiences issues. 

5 Common misconceptions of The Merge

1. Stakers get unburnt fees

Not all of Ether is burnt in a transaction fee. Unburnt fees, or tips on the execution layer, will be sent to stakers. This is due to proof of stake that will exist after the merge. In addition to new Ether minted as a block reward, you also get 30% of all transaction fees. 

2. Once the merge happens, you will be able to withdraw ETH

You won’t be able to withdraw your ETH post-merge. There will be another update about 6 months later, at which point you’ll be able to withdraw. Keep in mind that the ETH you stake will be locked until the update to withdraw exists. The merge aims to keep simplicity, focusing on one step at a time.

3. The merge will reduce gas fees

This is not the case. Sharding will reduce gas fees, but this will be a focus post-merge. This later phase is expected in 2023. It should be known that Layer 2s will begin to take on a larger role post-merge as well.

4. Running a node post-merge requires ETH

This is another misconception. Ethereum never required ETH to run a node. You can be a staking validating node and add transactions to the blockchain, or you can be a listening node and send transactions to the mempool via your own node. It’s easy and accessible to run a node. No ETH is necessary in order to run a node.

5. A new ETH2 token will exist and be minted

This is not true, since the Ethereum network won’t have a new network, nor a new token. This is why the Ethereum Foundation is doing away with the “Eth1” and “Eth2” terminology. 

What are some testing strategies currently used for The Merge?

Source

Most recently, Ethereum developers ran a test called the Kiln merge tesnet, which allows the community to practice running nodes, deploying contracts, testing infrastructure, and more. 

The Kiln testnet uses “shadow forking”, which inherits the state of existing testnets and allows us to stress test our sync assumptions as well as assumptions around how long it takes to build a block/timeouts. Kiln is expected to be the last merge testnet before existing public testnets are upgraded. 

The main focus is that Ethereum encourages users to continue testing the merge in order to ensure it functions fully before the actual event of the merge.

What are the timelines for The Merge testnets and mainnets?

Most of the testnets and mainnets will be determined in the future. However, the next test is set for April 22. The purpose of these tests are to surface any potential issues and resolve them as soon as possible. This will make it more comfortable for developers to familiarize with Ethereum, post-merge.

With that being said, Ethereum developer Time Beiko expects that The Merge could happen in July of 2022 as a “rough estimation”. According to his colleague, Ethereum developer Marius Van Der Wijden, it’s only a matter of time before The Merge becomes a historical event.

How to help Ethereum launch The Merge?

There are many ways you can help, from staking ETH, to running a client, to finding and reporting bugs, and even by joining the Ethereum development Discord channel. 

Stake ETH

If you currently have Ethereum, you have the ability to stake it into the blockchain. This will make users become validators, enabling them to earn rewards while also securing the network. 

Staking is more sustainable for the environment. There are several ways to stake with Ethereum, which includes solo staking, staking as a service, pooled staking, and through centralized exchanges.

Run a Client

If you’re interested in diving deeper into helping Ethereum, you can also run a client. This will mean you will be able to run software that runs the blockchain, checks transactions, and creates new blocks. This is also known as using “consensus later clients”, in which Ethereum provides a distribution of clients.

Find and Report Bugs

Finally, for those that have more technical backgrounds, finding bugs within Ethereum can be one of the most helpful tasks you can do. Reporting bugs can enable you to earn up to $50k USD. Ethereum has a leaderboard that also shows the top bug hunters. 

Join the Community

In addition, joining the Ethereum community through the Eth Research and Development Discord can also be helpful. They specifically have a Merge #testing channel for people to collaborate!

Merge Overview

Technical Aspects of Ethereum Merge

Definitions, Risks, and How You can Help

The time is coming when Ethereum moves from proof of work to proof of stake. While proof of work is fully reliable and secure, ensuring thousands of nodes will reach a consensus, it comes at a cost. Proof of work requires a lot of computing power to solve complex problems, and because of this, also requires lots of energy.

Proof of stake does not require energy-intensive equipment and still improves efficiency, increases decentralization, and resists censorship. Proof of stake will become the new standard for the entire network. Throughout this article, we’ll explain The Merge and tell you ways you can get involved.

What steps on the Ethereum roadmap are required for The Merge?

Source

Steps required on the Ethereum roadmap to get to The Merge include the addition of the beacon chain, removing the proof of work consensus layer, and merging proof of stake into the Ethereum mainnet.

What is the Beacon Chain?

The Beacon Chain is a fully independent decentralized network running parallel to the Ethereum Mainnet that uses the proof of stake consensus mechanism instead of Ethereum’s current Proof of work consensus mechanism. 

The purpose of the Beacon Chain is to support the transition from proof of work to proof of stake, and it is the first step needed to complete the merge.

The Beacon Chain transition started in November 2020 when a one-way bridge started moving the proof of work chain to the proof of stake chain and started accepting deposits. One month later, the Beacon Chain launched and secured millions of ETH across several validators. So far the Beacon Chain has not experienced any downtime or network interruptions.

What is the Merge?

The Merge is a planned Ethereum network upgrade that removes the proof of work consensus layer and merges the Beacon Chain’s proof of stake network into the current Ethereum mainnet. Ethereum’s consensus mechanism is a contribution to the network following Eth1. Eth1 was known as the execution layer. This will soon be deprecated as we migrate towards Eth2, now renamed The Merge.

Primarily The Merge will focus on the execution of upgrading the consensus mechanism and  bringing it in line with its original mission: to migrate from proof of work to proof of stake, validate transactions on the blockchain, and add new blocks.

Source

What happens to Ethereum’s consensus layer and data layer during The Merge?

During The Merge, the consensus layer is upgraded, and the data layer will remain unchanged. Ethereum’s blockchain data is structured so that it consists of two fundamental elements: a pointer and a linked list.

A linked list is a list of chained blocks that contain data and use pointers that point toward the previous block. Since The Merge is not the launch of a new version of Ethereum but rather an upgrade, the data layer won’t be affected in this process.

Once this transformation is complete, Ethereum will now be at a point of a more sustainable, eco-friendly ecosystem. 

What happens after The Merge?

After The Merge, the Ethereum blockchain will prioritize adding new features planned through a separate upgrade, a post-merge cleanup, and sharding. Some of the planned features include things like allowing stakers to withdraw staked ETH. 

The post-merge "cleanup" upgrade addresses these features, which is expected to happen very soon after The Merge is complete. 

Source

Finally, the process of sharding will be used to further scale Ethereum. Right now, Ethereum can only handle about 15 transactions a second. With sharding, Ethereum will have the capabilities to scale thousands of transactions by splitting the blockchain into “shards” (separate chains).

Sharding is a commonly used Web2 strategy for scaling databases. However, with Ethereum, this will lower the barrier of entry for validators to store and run data and is much more convenient than running the entire blockchain. Running an Ethereum node from your laptop or mobile device would soon be possible thanks to shard chains.

What are the risks of The Merge?

If The Merge fails, it could create a chain reaction that affects other blockchains and ecosystems dependent on Ethereum. 

There is a lot of hope going for the Ethereum merge, but that also comes with risks involved for all Ethereum network participants. 

The Merge has an important role in making changes to a current protocol managing hundreds of billions of dollars in assets. It's been known that The Merge has been delayed a number of times. 

The most recent delay was in June announcing that The Merge won’t happen in June, but a few months after. The Merge is now expected to ship in Q3 or Q4 of 2022.

Ethereum functions as the base layer for thousands of decentralized apps (dApps). Failure of The Merge could affect many dApps, ranging from altcoins like Basic Attention Token (BAT) to Layer 2s like Polygon (MATIC) and metaverse tokens like Sandbox. In addition, NFTs, DAOs, and other encrypted technologies could be affected.

If The Merge fails to meet expectations, Ethereum currently has 4 unique client implementations of proof of stake Ethereum nodes. This means proof of stake node operators can switch to different clients, if one experiences issues. 

5 Common misconceptions of The Merge

1. Stakers get unburnt fees

Not all of Ether is burnt in a transaction fee. Unburnt fees, or tips on the execution layer, will be sent to stakers. This is due to proof of stake that will exist after the merge. In addition to new Ether minted as a block reward, you also get 30% of all transaction fees. 

2. Once the merge happens, you will be able to withdraw ETH

You won’t be able to withdraw your ETH post-merge. There will be another update about 6 months later, at which point you’ll be able to withdraw. Keep in mind that the ETH you stake will be locked until the update to withdraw exists. The merge aims to keep simplicity, focusing on one step at a time.

3. The merge will reduce gas fees

This is not the case. Sharding will reduce gas fees, but this will be a focus post-merge. This later phase is expected in 2023. It should be known that Layer 2s will begin to take on a larger role post-merge as well.

4. Running a node post-merge requires ETH

This is another misconception. Ethereum never required ETH to run a node. You can be a staking validating node and add transactions to the blockchain, or you can be a listening node and send transactions to the mempool via your own node. It’s easy and accessible to run a node. No ETH is necessary in order to run a node.

5. A new ETH2 token will exist and be minted

This is not true, since the Ethereum network won’t have a new network, nor a new token. This is why the Ethereum Foundation is doing away with the “Eth1” and “Eth2” terminology. 

What are some testing strategies currently used for The Merge?

Source

Most recently, Ethereum developers ran a test called the Kiln merge tesnet, which allows the community to practice running nodes, deploying contracts, testing infrastructure, and more. 

The Kiln testnet uses “shadow forking”, which inherits the state of existing testnets and allows us to stress test our sync assumptions as well as assumptions around how long it takes to build a block/timeouts. Kiln is expected to be the last merge testnet before existing public testnets are upgraded. 

The main focus is that Ethereum encourages users to continue testing the merge in order to ensure it functions fully before the actual event of the merge.

What are the timelines for The Merge testnets and mainnets?

Most of the testnets and mainnets will be determined in the future. However, the next test is set for April 22. The purpose of these tests are to surface any potential issues and resolve them as soon as possible. This will make it more comfortable for developers to familiarize with Ethereum, post-merge.

With that being said, Ethereum developer Time Beiko expects that The Merge could happen in July of 2022 as a “rough estimation”. According to his colleague, Ethereum developer Marius Van Der Wijden, it’s only a matter of time before The Merge becomes a historical event.

How to help Ethereum launch The Merge?

There are many ways you can help, from staking ETH, to running a client, to finding and reporting bugs, and even by joining the Ethereum development Discord channel. 

Stake ETH

If you currently have Ethereum, you have the ability to stake it into the blockchain. This will make users become validators, enabling them to earn rewards while also securing the network. 

Staking is more sustainable for the environment. There are several ways to stake with Ethereum, which includes solo staking, staking as a service, pooled staking, and through centralized exchanges.

Run a Client

If you’re interested in diving deeper into helping Ethereum, you can also run a client. This will mean you will be able to run software that runs the blockchain, checks transactions, and creates new blocks. This is also known as using “consensus later clients”, in which Ethereum provides a distribution of clients.

Find and Report Bugs

Finally, for those that have more technical backgrounds, finding bugs within Ethereum can be one of the most helpful tasks you can do. Reporting bugs can enable you to earn up to $50k USD. Ethereum has a leaderboard that also shows the top bug hunters. 

Join the Community

In addition, joining the Ethereum community through the Eth Research and Development Discord can also be helpful. They specifically have a Merge #testing channel for people to collaborate!

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ALCHEMY SUPERNODE - ETHEREUM NODE API

Scale to any size, without any errors

Alchemy Supernode finally makes it possible to scale blockchain applications without all the headaches. Plus, our legendary support will guide you every step of the way.

Get started for free
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