The upcoming Ethereum Cancun upgrade will bring changes to the execution layer (EL) and consensus layer (CL). This article discusses the EIP protocols that will be upgraded and the changes they will bring. The article is sourced from the author BLOB and compiled by BlockBeats.
Introduction
What is EIP?
EIP-1 defines EIP as “Ethereum Improvement Proposals”. EIPs are design documents that provide information to the Ethereum community about new features or changes to Ethereum, its processes, or environment. Anyone can start a discussion on forums like Ethereum Magicians or Ethereum Research to propose changes they want to see on Ethereum. Once a consensus is reached on the idea, the author can write an EIP-1 following the process described in the EIP.
What are the execution layer and consensus layer?
Since the Ethereum merger (also known as the Paris upgrade), Ethereum has been operating on two separate and isolated layers: the execution layer (EL) and the consensus layer (CL). These layers have different functions and together form the PoS version of the Ethereum blockchain:
– Execution Layer (EL): Responsible for applying the changes brought by transactions to the blockchain. For example, when Alice wants to exchange 10 WETH for BLOB, she needs to send a transaction to the Ethereum blockchain specifying the exchange. The EL executes the necessary code (token swap on Sushiswap) and updates Alice’s token balance and approval, effectively modifying the blockchain’s database. The EL can be imagined as the engine of Ethereum that powers the actions on the blockchain.
– Consensus Layer (CL): Responsible for achieving consensus among all blockchain nodes. As Ethereum is supported by a decentralized network of participants (usually called nodes), all participants must agree on the blockchain. If this consensus is not achieved and Ethereum nodes disagree, we would have a situation where part of Ethereum believes Alice has 10 WETH while another part believes Alice has no WETH. The CL can be imagined as the steering wheel of Ethereum, defining the path the Ethereum blockchain will take.
Dencun: What is it?
Dencun = Deneb + Cancun
Since Ethereum is now composed of two independent layers, both layers need to undergo their own modifications to support large-scale changes (such as EIP4844). Therefore, major upgrades now require upgrades to both layers. To refer to the general Ethereum upgrade that involves upgrading both layers, the Ethereum core developers use the name Dencun, which is obtained by combining the names of the individual layer upgrades:
– Shapella = Shanghai (EL) + Capella (CL)
– Dencun = Cancun (EL) + Deneb (CL)
Interestingly, EL upgrades are named after cities, while CL upgrades are named after planets.
Deneb: Consensus Layer EIP
– EIP-4788: Beacon Block Root in EVM
This EIP introduces “proofs” of consensus conditions and makes them available for smart contracts on Ethereum (located in the EL). Systems like staking pools, re-staking protocols, and bridges will benefit from improved trust assumptions during execution.
– EIP-4844: Sharding Blob Transactions
This EIP introduces a new transaction format called “Blob transactions” that will be adopted by L2 networks like Arbitrum and Optimism to compress their L2 transactions on Ethereum. This improvement also establishes a separate fee market for these transactions, meaning Ethereum users and L2 networks will have their own gas prices and won’t compete in the Ethereum fee market.
– EIP-7044: Voluntary Exit with Permanent Validity Signature
This EIP improves the quality of life for Ethereum validators executing with split certificates, making it easier to withdraw a validator’s stake when the validation certificate and withdrawal certificate are held separately.
– EIP-7045: Increase Max Proof Inclusion Slots
This EIP extends the longest time for submitting proofs of proposed Ethereum blocks. Proofs are “votes” by validators on proposed blocks, and enough votes determine whether a new block will be accepted and added to the blockchain.
– EIP-7514: Increase Max Epoch Churn Limit
This EIP intends to introduce a limit on the “epoch churn limit,” which directly translates into a limit on the “maximum validator growth rate.” Ethereum core developers aim to limit the rate at which Ethereum validators increase in order to have more time to research comprehensive solutions to address potential issues when 100% of ETH is staked.
Cancun: Execution Layer EIP
– EIP-1153: Transient Storage Opcodes
This EIP introduces the TLOAD and TSTORE opcodes to the Ethereum Virtual Machine. These opcodes are used to specify that certain smart contract data is temporary and should return to its original value before the transaction is completed. This allows smart contracts to have storage that only changes within a transaction. Many contracts and protocols will benefit from this as the gas cost of variables used in reentrancy protection will be reduced.
– EIP-4788: Beacon Block Root in EVM
This EIP is of interest to both the CL and EL layers.
– EIP-4844: Sharding Blob Transactions
This is the beloved EIP-4844, which has been discussed in the Deneb section.
– EIP-5656: MCOPY Memory Copy Opcode
This EIP introduces the MCOPY opcode to the Ethereum Virtual Machine, allowing a segment of memory to be copied and written to a different location in memory during smart contract execution.
– EIP-6780: SELFDESTRUCT Only in Same Transaction
This EIP is part of the deprecation roadmap. It changes the behavior of the SELFDESTRUCT opcode to delete an account only when the opcode is executed in the same transaction that creates the contract. This opcode has long been intended for deprecation as it hinders the immutability of the Ethereum blockchain.
– EIP-7516: BLOBBASEFEE Opcode
This EIP introduces the BLOBBASEFEE opcode, which returns the current base fee of data blobs. Similar to how transaction fees work on Ethereum today, data blob transactions will be priced using a flexible base fee mechanism that determines the total gas price for sending such transactions. Just like normal transaction base fees, the blob base fee will gradually increase if the number of blob transactions exceeds the target transaction count, and decrease if it falls below the target transaction count.
Related Reports:
– How does Metis achieve true decentralization on Layer 2 after the Cancun upgrade?
– What will happen to the market after the Ethereum Cancun upgrade: Layer 2 “internal strife”?
– Latest progress on the Ethereum Cancun upgrade: Devnet 12, planning process, network specifications