CoolWallet Supports Optimism (OETH), a Layer-2 ETH scaling solution

CoolBitX is excited to announce that CoolWallet Pro now supports Optimism (OETH). This Ethereum layer-2 scaling solution is our latest supported optimistic rollup chain following our recent Arbitrum integration.

CoolWallet Pro is one of the best Optimism hardware wallets on the market and allows users to send and receive OETH in secure cold storage thanks to its EAL6+ secure element, encrypted Bluetooth and biometric verification process. Coming soon, CoolWallet will offer a MetaMask integration with Optimism and the ability to purchase OETH directly from our CoolWallet App.

Contents

• Secure layer-2 chain cold storage for Optimism, Arbitrum and Polygon
• What is Optimism (OETH)?
• How does an Optimistic Rollup work?
• How is an optimistic rollup (OR) different from a zero-knowledge (ZK) rollup?

Secure layer-2 chain cold storage for Optimism, Arbitrum and Polygon

Two of the biggest pain points for Ethereum and its users remain its congested network and high gas fees whenever the network is very busy. These are issues that will not be solved by the Ethereum Merge, but only be addressed with further upgrades a few years away, such as sharding.

Layer-2 scaling solutions like Optimism, Arbitrum and Polygon (MATIC), all supported by CoolWallet, should continue to play an important role in alleviating stress from the Ethereum main chain by helping to process some transactions off-chain. This is vital to sustain network growth on Ethereum as it continues to scale, by making it affordable for both developers and users to participate and build the dynamic new smart contract-powered sectors of DeFi, GameFi, NFTs, SocialFi,  metaverse and more.

What is Optimism (OETH)?

Optimism is a low-cost and ultra-fast Ethereum Layer-2 blockchain that uses an Optimistic Rollup network design in order to benefit from the strong and proven security of Ethereum while reducing its gas fees and network latency.

How does an Optimistic Rollup work?

An "Optimistic Rollup" network is a layer-2 blockchain protocol designed to lessen computing demands on a parent chain like Ethereum's base layer by processing transactions off-chain and publishing results on-chain as calldata, thereby reducing gas costs and helping its parent network improve 10-100x in scalability.

An Optimist Rollup does this by piggy-backing off the superior security of its parent blockchain, in this case Ethereum. It does this by using the consensus mechanism, such as Proof-of-Stake (PoS) or Proof-of-Work (PoW) of their parent chain instead of providing their own. Parent chains are usually more secure thanks to a higher degree of decentralization and network participants.

How is an optimistic rollup (OR) different from a zero-knowledge (ZK) rollup?

Optimistic rollups like Optimism and Arbitrum are "optimistic" in the sense that they consider transactions that happen off-chain to be valid and accurate, and therefore don't need to post cryptographic proofs of validity for these transaction batches on-chain.

Zero-knowledge (ZK) rolllups on the other hand do publish these proofs of validity for the off-chain transactions.

Instead ORs use a scheme that works like this: after a batch is posted, there's a certain period of time alloted (called the "challenge period") for other parties to challenge the results of an optimistic rollup transaction by processing a"fraud proof". If the fraud proof is successful, the transactions are rolled back and the processor is penalized. If the fraud proof fails or there challenge period elapses, the transactions is considered validated and processed on Ethereum.

How to bridge ETH and ERC20 assets between Optimism and Ethereum

Optimism is designed so that users can send arbitrary messages between smart contracts on Optimism and Ethereum. This enables users to bridge (transfer) assets such as ERC20 tokens, between the two networks.

Optimism uses this functionality in the Standard bridge to allow users to deposit assets (ERC20s and ETH) from Ethereum to Optimism and withdraw the same back from Optimism to Ethereum.