CBE Blockchain Interoperability and Scalability 3

Question 1

What is a Hash Time-Locked Contract (HTLC) primarily used for?

Accepted Answer

Enabling trustless cross-chain atomic swaps by combining hash locks and time locks

Answer

Securing smart contract code from reentrancy attacks

Answer

Compressing transaction data for rollup submissions

Answer

Encrypting validator communications in a PoS network

Question 2

What does 'finality' mean in the context of blockchain scalability and interoperability?

Accepted Answer

The point at which a transaction is considered irreversible and cannot be reorganized out of the chain

Answer

The total number of transactions a chain can process per second at peak capacity

Answer

The maximum block size a chain allows for scalability purposes

Answer

The process of finalizing a cross-chain bridge transfer with cryptographic proof

Question 3

What is 'data availability' and why is it critical for Layer 2 rollup security?

Accepted Answer

The guarantee that transaction data posted to L1 is publicly accessible so anyone can reconstruct the L2 state and detect fraud

Answer

The bandwidth available to process transactions on the L2 network

Answer

The replication of L2 node data across geographically distributed servers

Answer

The encryption scheme used to protect private transaction data on rollups

Question 4

What is Ethereum's EIP-4844 (Proto-Danksharding) designed to improve?

Accepted Answer

Reducing the cost of posting rollup data to Ethereum by introducing temporary 'blob' data storage

Answer

Enabling Ethereum to process 100,000 TPS natively without Layer 2 solutions

Answer

Implementing full sharding with 64 shards for parallel transaction processing

Answer

Adding native cross-chain messaging to the Ethereum protocol

Question 5

Which interoperability approach uses 'light clients' to verify cross-chain transactions without trusting a centralized bridge?

Accepted Answer

IBC's on-chain light client verification, where each chain runs a light client of the other

Answer

Multisig bridge relayers where 5-of-9 signers approve transfers

Answer

Centralized custodian holding assets on behalf of both chains

Answer

Wrapped token bridges backed by audited smart contracts

Question 6

What is the key security risk of a 'trusted' or 'custodial' cross-chain bridge?

Accepted Answer

A compromised custodian or multisig can steal all locked assets, making bridges high-value hack targets

Answer

Bridges slow down transaction finality on both connected chains

Answer

Trusted bridges cannot support ERC-20 tokens, only native assets

Answer

Custodial bridges require on-chain governance votes for every transfer