On Day 11, we will focus on another oldie, but this time from a DA perspective.

🔸 @Arbitrum Nova – AnyTrust Optimium, which differs from Arbitrum One by not posting transaction data on-chain but instead relying on its own DAC.

🧵 Full summary below! 👇 Let’s start with Arbitrum Nova Risk Rosette:

The most important piece here is its Data Availability – a well-setup DAC:

Sequencer Failure - Self Sequence 🟢
In the event of a sequencer failure, users can force transactions onto L1 with a 1d delay.

State Validation - Fraud Proofs (INT) 🟡
13 whitelisted actors can challenge invalid states using interactive fraud proofs. Challenge window: 6d 8h.

Data Availability - External (DAC) 🌕
Data is NOT posted on-chain. A 5/6 threshold DAC ensures availability.

Exit Window - 2d 🔴
Users have 2d to exit before an upgrade takes effect. After this, exit delays can extend significantly.

Proposer Failure - Self Propose 🟢
After 12d 17h of inactivity, anyone can step in and propose state roots.

Day 5 of the tech summary AC brings yet another project from DABEAT!

No. 5 - @AvailProject, public blockchain and data availability network combining erasure coding, KZG polynomial commitments, and data availability sampling. 🧵👇 Avail is a public blockchain and data availability network utilizing erasure coding, KZG polynomial commitments, and data availability sampling. At present, they provide $151.28M in economic security.

The wait is over! 🙌

Today, we’re excited to launch DABEAT - your go-to platform to explore Data Availability layers, essential for ensuring user access to L2 transaction data.

Maintained by L2BEAT team, DABEAT helps you assess the unique risks across the growing DA landscape. The new DABEAT section is organized into two core categories:

🚨 Major shakeup in Ethereum’s Layer 2 ecosystem: dYdX v3, a long-standing decentralized exchange, has shut down, leaving over $70M in user funds not withdrawn.

What happens to assets on an L2 when it stops, and what role does L2BEAT play? 🧵👇 Enter “Escape Hatches,” a built-in safeguard of StarkEx tech by @StarkWareLtd, which powers @dYdX. This fallback mechanism is designed to protect users' funds when an exchange becomes “frozen” - as dYdX v3 now is.

On August 16, OP Mainnet effectively disabled the fault proof system as part of a bug fix. The project has been set to Under Review as we further assess the situation. Given the unprecedented nature of this procedure, here are a few important comments and considerations 👇 Proof systems, generally speaking, are extremely complex. Optimism has taken exceptional care in making sure that users’ funds remain safe in the presence of bugs, and that any action performed by the OP Foundation can be reverted by the Security Council.

New Risk Rosette update! 🏵️

We’ve just updated the Upgradeability column into the Exit Window column!

The exit window addresses the question: in the event of an unwanted (potentially malicious) upgrade, how much time is available for users to exit before the upgrade is executed? It turns out that in most cases, simply examining timelock delays is insufficient. In the previous 'Upgradeability' column, one might assume that dYdX offers a longer exit window compared to instantly upgradable rollups like zkSync Era or OP chains.

We're thrilled to unveil "Stages", a maturity ranking for Layer 2 projects!

We've developed a comprehensive framework to track the evolution of L2 rollups from their early days to full decentralization. Let's dive into the details! 👇🧵 The initial idea and the first version of the ranking came from @VitalikButerin's proposal which you can read here: ethereum-magicians.org/t/proposed-mil…

Our research team kicks 2023 off with another security experiment. Read the full article here medium.com/l2beat/circumv… or a summary below 🧵👇🏻 /1 Last year was pretty tough for the crypto industry. Many people lost lots of money because they weren’t aware of the risks associated with the projects they were using. Let's fix it this year by having a public discussion around risks, and let's start with this thread. /2

Because of the recent @MetisDAO upgrade we're changing Metis' classification from "Optimistic Rollup" to "Optimistic Chain". Read on to learn more 🧵👇
l2beat.com On April 12 2022 the protocol architecture was significantly upgraded. The transaction data is no longer kept on-chain, instead it is kept in @Memo_Labs distributed data storage system.

We have just released a MASSIVE update on l2beat.com 🤩 New risk view, new research and more! Check it out yourself or keep reading about the details 💬 1/ DISCLAIMER: This update is the result of months of research and a lot of hard work. That said we surely made mistakes. Let us know about them! We'd love to discuss our findings with you and correct any errors! 2/