Great decoupling: What are Blobs and Blobspaces?

Author: 563, Bankless; Translation: Golden Finance 0xjs

If you’ve been paying attention to the cryptocurrency market, you may have heard about Ethereum’s “rollup-based” development roadmap. Through EIP-4844, the Ethereum mainnet introduces a new concept - Blobs (data blocks) to help these expansion solutions to achieve long-term expansion plans based on Rollup.

So, what exactly is a “Blob” and how exactly does it help Ethereum achieve long-term scaling through Rollup? Let’s take a closer look.

From full execution sharding to Rollup

Sharding involves randomly assigning validators to different shards (subgroups) of the blockchain, with each shard actually being its own mini-blockchain, running in parallel with the Beacon Chain.

This is not a new concept in blockchain design, Ethereum has long been planning to adopt this approach.

The only problem is that this is a complicated change and requires The time is too long. As Ethereum developers and researchers figure out how best to implement sharding, a new challenger has emerged – Rollup.

Rather than splitting the main Ethereum chain into its own mini-blockchain, Rollup acts as a mini-blockchain running on top of Ethereum Layer 1 (hence the name Layer 2). By the time Vitalik wrote his “Rollup-centric Ethereum Roadmap” article in 2020, one could already see that the situation was clear:

"When full execution sharding finally arrives, I don’t think anyone will care about it basically. Everyone has adapted to a Rollup-centric world, and whether we like it or not, by that time, it will be easier to continue on this path , instead of trying to bring everyone back to the base chain, which has no obvious benefit for us and is 20-100 times less scalable.”

Why EIP-4844 is a major change

Now that the Ethereum community has widely accepted Rollup as the future, which improvements could have the biggest impact on mainnet?

First, let’s briefly talk about the responsibilities of the blockchain in the Ethereum-Rollup relationship.

The original Ethereum vision was to scale execution on the mainnet through sharding . Now, since Rollup has scaled execution, this is no longer a priority.

What is the problem now? Data availability.

Rollup today still needs to publish transaction data (and fraud/validity proofs for settlement verification) to L1 so that everyone has a complete understanding of what is happening on the network. For Rollup, this is currently an expensive undertaking.

So while Rollup already helps scale execution, Proto-Danksharding (PDS, EIP-4844) is moving in the direction of helping scale data availability via “Blobs”.

Think of “Blobs” as a new type of tool, Rollup can efficiently store transaction and attestation data, thereby saving gas fees when sending this information to the mainnet. This new type of transaction provides a better way for L2 to interact with the L1 block space.

Although how much gas cost EIP-4844 actually saves will depend on Blobs are being adopted, but preliminary estimates suggest that Rollup’s transaction costs may be reduced by 10-100 times.

How many cents does it cost to transact on Ethereum’s Layer 2? Yes.

In fact, these fees could be so cheap that they could be completely subsidized by L2 sequencers in hopes of generating some buzz around their network. Given that Arbitrum and Optimism are already running token incentive programs, this isn’t such a ridiculous idea. Who doesn’t want to trade for free?

Great Decoupling

With the introduction of the Proto-Danksharding (PDS) update in EIP-4844, validators on the Ethereum mainnet will be able to handle L1 execution and blobs (containing L2 data and settlement/proofs). The best part is that this will be the first time these two sets of data will be separated into fee markets.

• Before EIP-4844 = Gas cost on L1 directly affects Gas cost on Rollup
• After EIP-4844 = Fully separated fee market for L2 blobs and L1 execution

The decoupling of the fee market is one of the reasons why Visa chose Solana as its stablecoin payment network.

A much-hyped NFT minting on the Ethereum mainnet will no longer impact DeFi users’ experience on their favorite Rollup. With fee markets segregated, these unnecessary entanglements will become a thing of the past.

Blobs will also inherit a “target allocation”, which will target three blobs per block for this stage. Blob fees will be maintained through operations similar to EIP-1559 to ensure that blobs do not clog the network. In this way, Blobs and L1 execution transactions can coexist harmoniously on the basic chain.

What to Expect

EIP-4844 is planned to go online in Dencun, the next upgrade of Ethereum, probably around January next year. After the mainnet upgrade, Rollup will have to undergo some upgrades to be able to properly build and send blobs to the mainnet.

Full Danksharding (FDS) is further on the Ethereum roadmap due to its complexity, but it plans to roll out a massive upgrade:

Data Availability Sampling (DAS) - Nodes do not have to download the entire data set to confirm that the data is present. They just need to do a random sampling (called a “data availability check”).

Thanks to DAS, blocks will be able to contain more blobs, and the blobs can be larger.

The best part is that once FDS arrives, Rollup won’t have to upgrade to support it - their upgrade to EIP-4844 will be enough.

With the launch of Proto-Danksharding, the Rollup-centric roadmap officially begins, laying the foundation for Ethereum’s next chapter. So as you enjoy essentially free deals on your favorite L2s next summer, remember to thank your friendly “Blob.”