On February 13, Arbitrum, which has been ridiculed for its "great technology but rubbish tokens", successfully completed the mainnet upgrade of BoLD technology, taking a key step towards permissionless verification.

At the same time, L2Beat upgraded Arbitrum’s status verification level from yellow to green. The Arbitrum upgrade is an important advancement for the Arbitrum ecosystem, and we have reason to pay attention and learn.#ARB#ETH #BoLD

To understand BoLD, we must first understand the basic logic of Arbitrum's Fraud Proofs. Fraud Proofs adopt the "most optimistic assumption", that is, all transactions are honest by default, unless a node finds a problem and challenges the block packager.

Arbitrum's innovative interactive fraud proof uses the K-segment method, efficiently identifying problematic segments by splitting disputed transactions into multiple segments, and then making final rulings through Ethereum.

However, Arbitrum's fraud proof mechanism also has a core issue: Who can propose blocks? And who can challenge the accuracy of these blocks? In the past, Arbitrum adopted a permissioned approach, where only authorized nodes could act as defensive validators, and dispute resolution was mostly in a one-on-one format. While this ensured system stability, it indeed posed a centralization problem.

BoLD has removed the permission requirements for validators, allowing any node to challenge the latest block, achieving a significant shift from 1 vs 1 to All vs All. This change means that the entire network's validation process is more decentralized, while also bringing new challenges:

📌Resource Attack: Malicious nodes may challenge every block, leading to network congestion and resource waste.

📌Delay Attack: Malicious nodes may continuously challenge the same block through multiple nodes, preventing Arbitrum from timely generating new blocks.

To counter these two types of attacks, BoLD has its own protective measures:

✅Resource Attack Protection: Nodes proposing challenges need to stake a certain amount of $WETH. If malicious nodes frequently propose challenges, they will ultimately lose a significant amount of ETH, greatly increasing the cost of attacks.

✅Delay Attack Protection: Arbitrum employs a parallel processing mechanism, ensuring that regardless of how many nodes challenge, the system can complete state confirmation within 2 * 6.4 days, avoiding delays in block generation.

At the same time, BoLD stipulates that proposing a block generation proposal requires staking 3600 ETH in advance, while proposing a challenge requires staking at least 3600 ETH.

Although Arbitrum offers staking pools, the threshold for ordinary nodes to stake ETH is relatively high. This design effectively mitigates the risk of malicious attacks.

👉In summary, BoLD has brought the following important technical upgrades:

1. Validators are permissionless, significantly enhancing decentralization.

2. Staking ETH prevents resource attacks, greatly increasing the cost of malicious attacks.

3. Parallel processing prevents delay attacks, ensuring efficient operation of the network.

4. Maximum time limit: The processing time for fraud proof of a block is limited to within 2 * 6.4 days, ensuring a quick response.

Although the launch of BoLD is a significant advancement in Arbitrum's technology, the abandonment of using $ARB for node staking operations does not bring significant benefits to token prices in the short term; this is merely a phase in Arbitrum's development.

In the future, Arbitrum has more tasks awaiting completion, including decentralized ordering, $ARB staking functionality, and enhancing Ethereum L2 interoperability, among others. Arbitrum is continuously moving towards a more efficient and decentralized goal.

I hope Arbitrum can lead the entire Layer 2 industry towards a more open and decentralized future, and achieve $ARB token empowerment, comprehensive interoperability, and traffic access as soon as possible.