CBSA Blockchain Network Architectures 3 — Questions and Answers
Question 1: What is the primary function of a 'relay chain' in the Polkadot network architecture?
- To store all transaction history
- To provide shared security and interoperability between parachains (Correct answer)
- To manage user wallets and identities
- To execute smart contracts for all connected chains
Correct answer: To provide shared security and interoperability between parachains
Polkadot's relay chain coordinates consensus and cross-chain communication, providing shared security to all connected parachains.
Question 2: Which factor primarily determines the 'finality' time in a blockchain network?
- The block size limit
- The consensus mechanism and number of confirmations required (Correct answer)
- The number of smart contracts deployed
- The geographic distribution of nodes
Correct answer: The consensus mechanism and number of confirmations required
Finality time depends on the consensus algorithm (e.g., PoW requires multiple confirmations while BFT-based systems offer instant finality) and the required confirmation depth.
Question 3: In a hybrid blockchain architecture, private transactions are typically handled by:
- Broadcasting to all public nodes first
- Off-chain databases with on-chain hash anchoring (Correct answer)
- Encrypting data in public blocks
- Using a separate consensus mechanism only for private data
Correct answer: Off-chain databases with on-chain hash anchoring
Hybrid architectures often store sensitive data off-chain while anchoring cryptographic hashes on the public chain to ensure integrity without exposing private information.
Question 4: What does 'sharding' accomplish in a blockchain network architecture?
- It splits large files before storing them on-chain
- It divides the network into smaller partitions that process transactions in parallel (Correct answer)
- It creates backup copies of the blockchain across regions
- It separates validator nodes from storage nodes
Correct answer: It divides the network into smaller partitions that process transactions in parallel
Sharding partitions the blockchain network into smaller groups (shards) that process transactions concurrently, dramatically increasing overall throughput.
Question 5: A blockchain architect needs nodes in different organizations to see only their relevant transaction data. Which Hyperledger Fabric feature addresses this?
- Endorsement policies
- Private data collections (PDC) (Correct answer)
- Chaincode lifecycle
- Gossip protocol
Correct answer: Private data collections (PDC)
Private Data Collections in Hyperledger Fabric allow subsets of channel members to keep specific transaction data private, sharing only a hash on the public ledger.
Question 6: In blockchain network design, what is a 'genesis block'?
- The block containing the most transactions
- The first block in the blockchain that establishes the chain's initial state (Correct answer)
- A special block used during network upgrades
- The block with the highest difficulty target
Correct answer: The first block in the blockchain that establishes the chain's initial state
The genesis block is the first block (block 0) of any blockchain, hardcoded with the network's initial configuration and having no predecessor.
Question 7: Which network architecture pattern is BEST suited for a blockchain solution requiring both high throughput and strong privacy between competitors?
- Public permissionless blockchain
- Single-organization private blockchain
- Consortium blockchain with private data channels (Correct answer)
- Centralized database with blockchain audit log
Correct answer: Consortium blockchain with private data channels
A consortium blockchain with private data channels provides shared governance among competitors while enabling selective data visibility through dedicated private channels.
CBSA Blockchain Network Architectures 3
What is the primary function of a 'relay chain' in the Polkadot network architecture?