This article is forLearning to exchange and use does not constitute any investment advice. Please indicate the source for reprinting and contact the IOSG team for authorization and reprinting instructions. None of the projects mentioned in the article are recommendations or investment suggestions.

Two years ago, at the beginning of the rise of the modular blockchain narrative, we wrote an article presenting our views and predictions on the Data Availability (Data Availability) circuit. As we might expect, the modular blockchain narrative has prevailed and fueled infrastructure innovation, enhanced network interoperability, and fostered more collaboration and integration within the ecosystem, various Rollup as a Service (RaaS) solutions (Altlayer,Caldera, Conduit, Gelato) began to emerge. The following figure shows the interface of the Rollup development tool Conduit, showing that deploying Rollup and selecting DA solutions has become extremely simple and convenient.

Source: Conduit

In the past two years, alternative DA solutions (Alt-DA) such as Celestia, Eigenda, Avail, and Nearda have developed significantly, each showing unique technical advantages and market share. At the same time, with the launch of Ethereum EIP-4844, the introduction of blobs to replace calldata greatly reduced the cost of using Rollup in Ethereum's native DA layer. Today, developers and project parties face more trade-offs when choosing a data availability layer. This article will track and analyze existing DA solutions, explore in depth their performance costs, technical characteristics and market performance, and present our views and thoughts on future DA circuit development.

1.Status of adoption of existing DA schemes

Rollup, which uses Ethereum's native DA on-chain solution, mainly focuses on mainstream Layer 2 solutions that have been updated from CallData storage to suit BLOB, including Arbitrum, Optimism, and Base, as well as Starknet, zkSync, and Scroll. By using Ethereum as the DA layer, Rollup data is verified and stored by all Ethereum nodes, and benefits from Ethereum's security, degree of decentralization, continuity of protocol upgrades, and economic incentives. Comprehensive L2 occupies an important position in the Ethereum ecosystem, and requires the use of the above orthodoxy brought about by native DA as the core difference. (Vitalik believes that the core of Rollup is an unconditional security guarantee: you can take out your assets even if everyone is against you. If data availability depends on an external system, this equivalent security cannot be obtained)

However, posting data to the Ethereum mainnet was associated with high costs, especially before EIP - 4844 (calldata cost was 16 gas per byte; in December 2023 alone, L2 spent more than 15,000 ETH on DA costs). As a result, various Alt-DA off-chain solutions have emerged, such as Celestia, Eigenda, and Avail, which is not yet online. Through various technical means, such as DAS, erasure codes, KZG promises, etc., the cost of data storage and transmission has been reduced.

Among these, Celestia, as a modular blockchain dedicated to DA, has become the leading project on the DA circuit since the main network was launched in October 2023. The main target customers include projects requiring a modular architecture: cross-chain bridges, settlement layer solutions, defi projects, games, sequencers, and Layer 2 solutions not limited to the Ethereum ecosystem. Its current customers include Omnichain DEX protocol Orderly, modular L2 Manta Pacific tailored for EVM-native ZK applications, Base-based L3 Hokum, and DEX Lyra and Aevo, which focus on derivatives trading. As a DA layer pioneer in modular design that is not limited to a specific ecosystem, Celestia's advantages make it the first choice for many emerging Layer 2 projects.

EigenDA was developed by EigenLabs and uses EigenLayer's restaking mechanism to provide an efficient, secure, and expandable DA service solution, inheriting to a certain extent the security of the Ethereum main network and a large network of validators. Eigenda is focused on providing high performance DA solutions for the Ethereum ecosystem. As the first active verification service (AVS) on Eigenlayer, eigenda was launched along with the EigenLay mainnet in April. The existing customer base is equally diverse, including Ethereum L2 Swell, Celo, Mantle Network, and many other AVS built on EigenLayer, such as the decentralized computing stack Versatus, Polymer, DEX Protocol DODO, and CyberConnect as Social L2.

Source: eiGenda

2.The trade-off between native DA (EIP-4844) and existing Alt-DA

2.1 Ethereum native DA

Source:Dune & Growthepie

Blob capacity and storage characteristics:

• Each block can hold up to 6 blobs

• Each blob can store up to 128 KB of data (even if 128 KB of space is not fully used, the sender is charged for the full blob)

The new blob gas market operates in a manner similar to EIP-1559. The basic blob fee is adjusted according to changes in supply and demand:

• If the number of blobs in a block exceeds the target (currently 3), the basic blob fee is increased.

• If the number of blobs in a block is less than the target, reduce the basic blob fee.

Source: IOSG Ventures

Source: Dune/Ethereum block blob count 3-day EMA

L2 mainly uses the newly introduced Type 3 transactions. The max_fee_per_blob_gas and blob_versioned_hashes fields are added to the previous transactions, representing the maximum cost per blob gas that users are willing to pay and the hash output list of kzg_to_versioned_hash, respectively.

This new pricing mechanism means that Type 3 transactions still require the max_fee_per_gas and max_priority_fee_per_gas fields and are subject to the existing EIP-1559 market. In addition to blob space, type 3 transactions still need to pay for the EVM space they use.

As a result, blobs still compete for block space, causing cost uncertainty because each block has limited blob space, and the gas fee market for blobs is dynamically adjusted according to demand.

Therefore, as a general chain, Ethereum's shortcoming also lies in the uncertainty of the blockchain space — it is possible that the sudden emergence of on-chain activities such as NFT minting and airdrop claims will cause on-chain congestion, and the pricing of blobs will be raised, making Rollup unable to estimate the cost base. This will cause the Rollup expenditure budget to be uncertain, leading to unstable profit margins and an increaseBarriers to the use of new projects that are still in their infancy make it difficult for project partiesTo determine whether Ethereum DA can be used as a long-term solution. Most of the time in the figure below, using blobs will be about 98% cheaper than using Calldata, but in the figure below, you can see that using Blobs for a certain period of time is only 59% cheaper than using Calldata.

Source: Ethernow

Here's an example of how much we calculate the cost of two blob transfers:

Source:Ethernow

The figure shows a Zksync Validator Timelock Type 3 transaction in a block on March 28, 2024. Let's calculate its data cost by breaking down the basic execution fee and priority fee based on blob fees:

Assuming that the price of Ethereum was $3600, the data cost using 1 Mib blob at the time was approximately:

4×0.018ETH×3600USD/ETH = 259.2USD

Let's take another zksync era type 3 transaction on June 24:

Source:Ethernow

At that time, there was a slight decline in mainnet activity. Let's break down the data cost:

The approximate cost of using a 1Mib blob of data at the time was:

4×0.0021ETH×3600USD/ETH = 30.24USD

It can be seen from this that the cost of using blobs to transfer data is uncertain, and it is still relatively high. However, for a rollup, the stability of the cost structure is one of the key considerations when choosing a DA solution.

2.2 Celestia

As the pioneer of modular blockchains, Celestia focuses on providing the DA layer and the consensus layer, separating the execution layer, thereby specifically optimizing DA functions and improving efficiency and scalability. Celestia's L1 off-chain solution has many different technical characteristics compared to methods using the Ethereum chain, thereby reducing the cost of data availability and providing relatively higher flexibility and scalability. The modular design makes Celestia extremely flexible, allowing developers to freely choose the execution environment, not limited to a specific virtual machine (VM), so that Celestia can support various application scenarios and meet diverse needs.

If Rollup wants to integrate Celestia as the DA layer, it is necessary to submit transaction data (data blobs) generated by the execution layer to the Celestia network instead of the original Layer 1 (Ethereum) to ensure data availability for verification and transactions. Celestia's data availability sampling (DAS) technology recodes block data by using a two-dimensional RS erasure coding scheme, allows light nodes to verify data availability through multiple rounds of random sampling by downloading only a small portion of the block data, and allows multiple nodes to process different parts of the data in parallel, improving overall efficiency.

Source: Celestia.org

In terms of security, Celestia is based on the Tendermint consensus mechanism. Validators agree on data blobs, ensure the availability and consistency of data in the network, and can tolerate up to one-third of the validator nodes to fail or maliciously. By staking TIA tokens, Celestia's validators are financially incentivized to ensure honest conduct and punish malicious acts or misconduct, thereby safeguarding the security of the network. Currently, Celestia's TVL is about 6.44 billion US dollars, and the total number of nodes is 100.

Regarding scalability, Celestia's block size can be dynamically adjusted according to the number of active light nodes in the network. As more nodes are added, Celestia can safely increase block size, theoretically increasing throughput and scalability indefinitely. Current data shows that its data throughput is approximately 6.67 Mb/s.

Celestia Blob capacity and storage characteristics and pricing mechanism:

To compare costs, we will briefly discuss Celestia's performance and pricing mechanism here. When a user submits data on Celestia, it is achieved by submitting a blob transaction (blobtX). The fee consists of blob space fees and gas fees.

Specifically, the maximum size limit for each blob is slightly less than 2 MiB (1,973,786 bytes), and each block can contain multiple blobs, depending on the total block size limit. The current maximum block size is 64x64 shares (about 2 MiB), for a total of 4096 shares, with one share reserved for PFB (PayForBlobs) transactions and the remaining 4095 shares for data storage. Celestia's fee marketplace is similar to Ethereum's EIP-1559 mechanism, using priority memory pools based on gas prices. Transactions with higher transaction fees are prioritized by validators, and the fee consists of a fixed fee per transaction and a variable fee based on the size of each blob.

According to the comprehensive statistics of Rollup data on Celenium (6/17), the DA cost for each Celestia integrated customer was between 0.02-0.25 Tia/Mib, equivalent to the price of $TIA on June 17 ($7.26), and DA costs for several major customers ranged from $0.15 to $1.82/MiB. As a result, Celestia provides a competitive and stable cost structure compared to native DA on the Ethereum chain.

Source: Celenium

Source:Celenium, gas price stabilized at around 0.015 uTia (1 uTIA = TIA × 10 − 6)

However, Celestia itself is a Layer 1 blockchain network that requires P2P networks to broadcast and agree on data blobs. Although light nodes can use DAS to ensure data availability, the network still has high requirements for all of its nodes (128 Mb/s download and 12.5 Mb/s upload), which poses an obstacle to decentralization and future throughput increases. In contrast, eiGenda uses a different architecture—no consensus or P2P networks.

As an active verification service (AVS) built using EigenLayer, eiGenda uses the security of Ethereum (there is no need to introduce a new set of validators, Ethereum validators can freely choose to join; eiGenda's re-pledge nodes are a subset of Ethereum nodes) to ensure data availability through a re-staking mechanism, making good and direct use of existing infrastructure. The main workflow is that Rollup Sequencer generates blob data and then sends it to the Disperser (can be run by Rollup itself, or through a third party, such as EigenLabs). Disperser will slice the blob data, generate a correction code and KZG promise, and then publish it to eigenda's node, then the eiGenda node will verify Attestation and ensure data availability. After the verification is complete, the node The data needs to be stored and a digital signature sent back to the Disperser. Finally, Disperser collects signatures and uploads them to the EiGenda smart contract on the Ethereum mainnet to verify the correctness of the final aggregated signatures.

The core idea is still to use technology to reduce the requirements for node data storage and verification computing power. However, eiGenda chose KZG promise verification technology consistent with the Ethereum upgrade to achieve it. Furthermore, eiGenda does not rely on consensus protocols and P2P transmission, but instead uses unicast to further increase consensus speed.

To ensure that the eiGenda node actually stores the data for use, eiGenda uses the Proof of Custody (Proof of Custody) method. If an inert validator appears, anyone can submit a certificate to the eiGenda smart contract, and the proof will be verified by the smart contract. If the validation succeeds, the lazy validator will be slashed.

Therefore, eiGenda's solution processes are all carried out on Ethereum, and Ethereum provides consensus guarantees, so there is no need to be limited by consensus protocols and bottlenecks with low throughput in P2P networks. Nodes do not need to wait for sequential sequencing, and can directly process data availability proofs in parallel, greatly improving network efficiency.

eiGenda's capacity performance and cost:

eiGenda currently has 266 node operators. Its maximum throughput target is 10 Mbps. According to the 7-day average data, EiGenda's data throughput is 0.685 MiB/s, and the data storage and transmission costs are about 0.001 Gas/Byte. In equivalent terms, assuming the gas fee is 10 Gwei and the price of Ethereum is $3600, the cost per 1 MB of data is about 0.038 US dollars. The total staked TVL is 33M ETH, close to $1.2 billion.

Comprehensive Comparative Analysis Celestia vs. eIGenda

From a technical perspective, Celestia and eiGenda differ in several ways. First, in terms of node load, all Celestia nodes need to handle broadcast, consensus, and verification. The download bandwidth requirement is 128 MB/s, and the upload bandwidth requirement is 12.5 MB/s, while Eigenda's node does not handle broadcast and consensus, the bandwidth requirement is only 0.3 MB/s, and it can use a subset of Ethereum nodes. Second, in terms of throughput, Celestia's maximum throughput was around 6.67 MB/s, while Eigenda's target reached a maximum of 10 MB/s. In terms of security, Celestia's security comes from its network value, with a pledge value of approximately $6.65 billion and attack costs of over $4 billion. eiGenda inherited part of Ethereum's security based on re-staked asset values and mainnet operator shares. The current TVL is close to 1.2 billion US dollars, which inherits about 2% of Ethereum's security.

Taken together, Celestia's competitive advantage lies in its flexible modular design and high data throughput, making it more popular among small to medium L2 and application chains. The advantage of eiGenda is that it uses the Ethereum infrastructure to decouple the legitimacy brought about by data availability and consensus. In the future, as the dual trend of modularity and application chains develops, Celestia may benefit from the incremental market, while eiGenda may occupy a larger share of the central Ethereum market, which requires greater security.

3. Avail and NEARDA

Although Celestia and Eigenda currently dominate the data availability market, the competitive landscape may change in the future. With the potential launch of Avail and NEARDA projects, the competitive landscape in the field of data availability is expected to further intensify.

Avail is a blockchain network focused on data availability and aims to provide efficient transaction sequencing and data storage services for EVM compatible blockchains and rollups. It uses BABE and GRANDPA consensus mechanisms inherited from the Polkadot SDK, avail uses KZG polynomial promises as proof of validity, supports up to 1,000 validators using nominated proof of stake (nPOS), and provides reliable backup through a unique lightweight client P2P network sampling mechanism.

On the other hand, NEARDA is a data availability solution launched by Near Foundation, which mainly provides DA services for ETH Rollup and Ethereum developers. Its goal is to provide a cost-effective DA solution that is as decentralized as Near Protocol. At present, strategic partnerships have been established with major players in the Ethereum ecosystem such as Polygon CDK, Arbitrum, and Optimism. 

However, in the short term, for Rollups, it is more effective to reduce sidesInternational costs are the best way to establish barriers. Among them, adjusting revenue and cost models to market conditions is a better solution.

4. DA for specific scenarios

In addition to the generic DA for Rollup described above, the current DA circuit has also spawned some relatively early DA projects that target specific scenarios, such as ZeroGravity (0G), a high-throughput DA solution tailored for AI, and Nubit, a Bitcoin DA solution.

4.1 Zerogravity (0G)

AI applications require different data availability than traditional blockchain applications. AI model training and operation requires processing large amounts of data, including model parameters, training data sets, real-time data requests, etc. This data needs to be stored and transmitted quickly and reliably to ensure the efficiency and performance of AI models. However, existing general-purpose DA solutions, such as Celestia and eiGenda, are mainly designed to meet the data availability requirements of ordinary blockchain applications, and have certain limitations when processing large-scale data transmission with ultra-high throughput and low latency.

ZeroGravity (0G) wanted to specifically meet the needs of AI applications through modular design and high-performance data transmission. Its modular design divides the data availability workflow into two channels for data publishing and data storage, so that the system can scale linearly as the number of nodes increases. The data storage channel focuses on big data transmission, ensuring that big data can be stored and accessed almost instantaneously. Data distribution channels, on the other hand, are used to guarantee the availability of data and verified through an arbitration system based on most honest assumptions. 0G Storage is an on-chain database composed of a network of storage nodes. Storage nodes participate through the “Proof of Random Access” (PorA) mining process to ensure data availability and integrity. It supports the storage of various types of AI-related data, including models, training data, user requests, and real-time retrieval of enhanced generation (RAG) data.

Source: 0G

4.2 Nubit

The Bitcoin ecosystem is gradually starting up and receiving attention, and various technical routes related to Bitcoin are also surging. With the development of these technology routes, applications such as Ordinals, Layer 2, and oracles are also increasingly in demand for efficient and secure data availability solutions. These applications need to be able to store and transfer large amounts of data quickly and reliably to ensure proper operation and improved user experience. For example, Ordinals requires efficient data storage and transmission to support the creation and trading of digital art, Layer 2 solutions require high throughput and low latency to achieve better scalability, and oracles require reliable data transmission to ensure data accuracy and timeliness.

Nubit is the first native data availability (DA) layer project in the Bitcoin ecosystem. It aims to solve the problem of limited throughput of the Bitcoin mainnet and provide infrastructure support for the long-term development of the Bitcoin ecosystem. Nubit's workflow includes multiple steps such as data submission, validation, broadcasting, storage, sampling, and consensus to ensure efficient processing and high availability of data. After the data submitted by the user is processed by RS coding, the validator node uses the NuBFT consensus algorithm to verify and generate KZG promises. The verified data block is broadcast to the entire network, the storage node is responsible for storing the complete data block, and the lightweight client verifies the availability of the data through the Data Availability Sampling (DAS) protocol. Even in the event of a network failure, the node can still recover data through full storage nodes and KZG on the Bitcoin network.

Nubit aims to provide infrastructure for Bitcoin ecosystem projects. It has established partnerships with various projects such as Babylon, Merlin Chain, and Polyhedra. Nubit will reduce data storage costs. For example, in the face of a surge in demand in the inscription market, Nubit can greatly reduce data publishing costs with Bitcoin Layer 2, making storing and processing data on Bitcoin more affordable.

5. Closing Thoughts

Analyzing the differences in DA circuit projects, we saw a series of unique technologies and market positions in terms of security (including data integrity, network consensus, etc.), customizability and interoperability, performance, and cost. With the widespread adoption of these DA solutions and differences in DA layer choices for different projects.

We believe more App-Rollups will be launched on the market in the future. However, despite the potential increase in the market, the DA circuit's head effect is obvious. Celestia, eiGenda, etc. will occupy the main market share, leaving few opportunities for the lower back and tail, and competition is also intensifying. Current capacity exceeds demand for Rollup. For example, after the launch of the main network, Celestia's network bandwidth utilization rate has been below 0.1% for a long time, far below its maximum supported capacity of 46,080 MB per day. However, compared to Ethereum's current 15 Rollups and 700 MB of data per day, Celestia's activity volume still has a lot of free space.

Of course, it is not ruled out that in the future, high-performance networks may require high DA bandwidth, or AI projects. In addition, there are also relatively early DAs that target specific scenarios, such as Bitcoin DA, which may gain a good market share in the segment.However, DA is essentially a to B business, and the revenue of DA project parties is closely related to the quantity and quality of ecological projects.At this stage, we don't think we need too many off-chain DA solutions on the market unless they make a few orders of magnitude leap in cost and efficiency.

Overall, looking at DA's business model now, there is sufficient supply, but the development of the racetrack is still evolving, and various solutions have shown different competitiveness in terms of technology and market positioning. Future development will depend on continued innovation in technology and dynamic changes in market demand.

References:

https://medium.com/@MTCapital_US/mt-capital-research-da-sector-analysis-comparative-study-of-celestia-and-eigenda-acc07ea5694f

https://www.theblockbeats.info/news/51171