CBE Blockchain Interoperability and Scalability 1 — Questions and Answers
Question 1: What is the primary purpose of a blockchain bridge?
- To transfer assets or data between two separate blockchain networks (Correct answer)
- To increase block size on a single chain
- To merge two blockchains into one unified ledger
- To synchronize node clocks across a network
Correct answer: To transfer assets or data between two separate blockchain networks
A blockchain bridge locks assets on the source chain and mints equivalent wrapped tokens on the destination chain, enabling cross-chain transfers.
Question 2: Which Layer 2 scaling solution bundles hundreds of transactions off-chain and submits a single proof to the main chain?
- ZK-Rollup (Correct answer)
- Lightning Network
- Plasma
- Sharding
Correct answer: ZK-Rollup
ZK-Rollups aggregate transactions off-chain and generate a zero-knowledge proof of validity, posting only the proof and compressed data to Ethereum mainnet.
Question 3: What distinguishes an Optimistic Rollup from a ZK-Rollup?
- Optimistic Rollups assume transactions are valid and use a fraud-proof challenge window instead of validity proofs (Correct answer)
- Optimistic Rollups use zero-knowledge proofs while ZK-Rollups use fraud proofs
- Optimistic Rollups process transactions on-chain while ZK-Rollups are fully off-chain
- Optimistic Rollups are only used on Bitcoin while ZK-Rollups are Ethereum-specific
Correct answer: Optimistic Rollups assume transactions are valid and use a fraud-proof challenge window instead of validity proofs
Optimistic Rollups post transactions assuming validity; a 7-day challenge window allows anyone to submit a fraud proof if a transaction is invalid.
Question 4: What is the Interplanetary File System (IPFS) primarily used for in blockchain applications?
- Decentralized content-addressed file storage to host off-chain NFT metadata and large files (Correct answer)
- Cross-chain communication between Ethereum and Bitcoin
- Sharding block data across validator nodes
- Storing private keys in a distributed manner
Correct answer: Decentralized content-addressed file storage to host off-chain NFT metadata and large files
IPFS stores files by their content hash, making it ideal for NFT metadata and large assets that are too expensive to store directly on-chain.
Question 5: What is 'sharding' as a blockchain scalability technique?
- Splitting the blockchain into parallel partitions (shards) so each node only processes a subset of transactions (Correct answer)
- Compressing block data to reduce storage requirements
- Dividing validator rewards into smaller increments
- Breaking smart contracts into modular components
Correct answer: Splitting the blockchain into parallel partitions (shards) so each node only processes a subset of transactions
Sharding horizontally partitions the blockchain so validator subsets process different transaction subsets in parallel, increasing overall throughput.
Question 6: Which protocol is specifically designed for cross-chain messaging and asset transfers using a hub-and-spoke model?
- Cosmos IBC (Inter-Blockchain Communication) (Correct answer)
- Polkadot XCM only
- Ethereum Bridge Protocol
- Hyperledger Fabric channels
Correct answer: Cosmos IBC (Inter-Blockchain Communication)
The IBC protocol in the Cosmos ecosystem enables sovereign blockchains to communicate and transfer assets through standardized message passing via a central hub.
CBE Blockchain Interoperability and Scalability 1
What is the primary purpose of a blockchain bridge?