CoinWorldNews Report:
Author: 1912212.eth, Foresight News
As Ethereum’s layer-two networks mature and gas fees significantly decrease, these networks are experiencing robust growth. However, accompanying challenges such as cost and speed variability have emerged, impacting user experience unfavorably. Against this backdrop, the importance of transaction sequencing has become increasingly prominent, pivotal to resolving transaction bottlenecks and optimizing user experience.
In April of this year, modular blockchain focusing on shared sequencers Astria completed a $5.5 million seed funding round led by Maven 11, with participation from 1kx, Delphi Ventures, and Robot Ventures. Just three months later, Astria secured an additional $12.5 million, led by dba and Placeholder VC, with Hasu among the contributors.
What is Astria?
Astria is developing a decentralized shared sequencer network designed to offer fast finality, censorship resistance, composability, and decentralization for Rollups.
Currently, L2 networks find it more convenient, cheaper, and easier for users to operate with a centralized sequencer. Despite L2 users being able to bypass sequencers by directly submitting transactions to L1, they must pay transaction gas fees on L1, potentially facing longer confirmation times.
Sequencers control transaction sequencing and theoretically have the authority to exclude user transactions. They can also extract MEV from transaction groups, posing increased centralization risks if only one sequencer exists.
Hence, a decentralized shared sequencer retains significance.
How Astria Operates
Astria’s decentralized sequencer comprises multiple sequencer nodes that sort Rollup transactions. In Astria’s operational model, users submit transactions to Rollups, which automatically enter respective Rollup node mempools. The combiners collect these transactions and forward them to sequencers. Finally, sequencers aggregate transactions into a shared block and send pre-confirmations to users.
Current sequencers are designed specifically for individual Rollups. Astria, however, processes blocks across multiple Rollups, potentially saving costs when publishing data to L1 through data compression. A decentralized shared sequencer network incentivizes participants from various Rollup ecosystems to act as validators on the network.
Astria Stack
Astria consists of five main components: combiners, sequencing layer, relayers, DA (Data Availability), and schedulers.
Combiners
While technically savvy individuals may interact directly with the sequencing layer for better transaction ordering, this approach increases complexity for most ordinary users. Astria provides combiners to abstract this complexity, acting as gas stations that manage transaction sequencing costs. Combiners also offer unordered guarantees, bundling transactions as received.
Sequencing Layer
Astria’s sequencing layer employs CometBFT as its consensus algorithm. Chains supporting CometBFT can utilize Inter-Blockchain Communication (IBC), facilitating interoperability with numerous other chains. The unique aspect of Astria’s sequencer is its transaction execution delay (deferred sequencing), assigning transactions to another execution engine like Rollup. Sequencer nodes can opt to act as validators, actively participating in new block production and finality.
Relayers
Relayers retrieve validated blocks from sequencers and transmit them to the DA layer. Since sequencer block times are faster than DA, relayers batch process ordered data from multiple sequencer blocks, compressing and submitting them to DA. Scheduler retrieves individual sequencer blocks before relaying them to DA, enabling improved user experience with rapid finality akin to soft commits in the execution layer. The dataset sent from relayers to DA serves as the definitive source for finality in Rollup.
DA (Data Availability)
Astria employs Celestia as its data availability layer, serving as the ultimate destination for all sequencer network-ordered data. Once data is written to Celestia, transaction order is considered final, ensuring all data extraction for new Rollup nodes originates here.
Schedulers
Schedulers function as consensus implementations for Rollup full nodes, akin to operational nodes in the OP Stack. They connect sequencers and DA layers to the Rollup execution layer by extracting required Rollup data from each sequencer block, validating batched Rollup data, and forwarding verified transaction lists to the execution engine for processing.
