Free Certified Blockchain Professional (CBCP) Enterprise Blockchain Platforms Questions and Answers — Questions and Answers
Question 1: A consortium of competing manufacturers wants to build a supply chain solution on Hyperledger Fabric. They need to share transactional data with their direct suppliers and logistics partners, but want to ensure that pricing and quantity details remain confidential from other competing manufacturers on the same network. Which Hyperledger Fabric feature is specifically designed to address this requirement?
- The ordering service
- Channels (Correct answer)
- The Membership Service Provider (MSP)
- State-based endorsement
Correct answer: Channels
Hyperledger Fabric's channels act as private 'sub-networks' within the main blockchain network. [5, 12] By creating a channel that includes only the manufacturer, its suppliers, and its logistics partners, all transactions and ledger data for that specific supply line are isolated and kept confidential from other members (like competing manufacturers) who are not part of that channel. [3, 6, 10]
Question 2: Which enterprise blockchain platform is architecturally designed around a 'need-to-know' principle, where transaction data is NOT broadcast to all nodes on the network but is instead sent directly and privately only to the participants involved in that specific transaction?
- Hyperledger Fabric
- Ethereum (public mainnet)
- ConsenSys Quorum
- R3 Corda (Correct answer)
Correct answer: R3 Corda
R3 Corda is uniquely designed to avoid global broadcasting of transactions. Instead, it uses a peer-to-peer communication model where transaction details are shared only on a 'need-to-know' basis with the parties directly involved and any necessary notaries. [16, 18, 23] This approach provides a high degree of privacy by default, as no node has a complete view of all transactions on the network. [17]
Question 3: A financial services consortium is using ConsenSys Quorum to settle private transactions between member banks. Which component is primarily responsible for managing the encryption, decryption, and secure distribution of the private transaction payloads to only the authorized participants?
- The GoQuorum client
- The Istanbul BFT consensus engine
- Tessera (Correct answer)
- The smart contract engine
Correct answer: Tessera
Tessera is the private transaction manager used by ConsenSys Quorum (and Hyperledger Besu). [1] Its core function is to handle the privacy of transactions by encrypting the payload, securely distributing it to the intended recipients off-chain, and replacing the private data on the main chain with a hash, ensuring only authorized parties can view the sensitive details. [2, 4]
Question 4: In Hyperledger Fabric's transaction lifecycle, what is the specific role of an 'endorsing peer'?
- To bundle transactions into blocks and send them to all peers.
- To validate the final block and write it to its local ledger.
- To execute a chaincode transaction proposal, sign the result, and return it to the client. (Correct answer)
- To manage the cryptographic identities and certificates for all network participants.
Correct answer: To execute a chaincode transaction proposal, sign the result, and return it to the client.
The endorsing peer's primary role is to receive a transaction proposal from a client application, simulate the transaction by executing the specified chaincode, and then sign the read-write set (the results). This signed proposal response, or 'endorsement', is sent back to the client. It does not commit the transaction to the ledger at this stage. [8, 21]
Question 5: An enterprise is evaluating blockchain platforms and notes a key difference in their underlying data structures. One platform, R3 Corda, is described as using a UTXO (Unspent Transaction Output)-like model, whereas platforms like Ethereum and Quorum use an account-based model. What is a primary characteristic of Corda's UTXO-like model?
- It maintains a global state of all account balances that is updated with each transaction.
- Transactions consume existing states as inputs and produce new states as outputs, which are then individually tracked. (Correct answer)
- It relies on a central server to calculate and broadcast the current balance of every participant.
- All transaction history for a single asset is stored within one globally accessible smart contract.
Correct answer: Transactions consume existing states as inputs and produce new states as outputs, which are then individually tracked.
Unlike the account model which tracks balances in a global state, Corda's ledger model is similar to the UTXO model. Each transaction consumes one or more existing states (inputs) and creates new, immutable states (outputs). The current state of the ledger is the collection of all unconsumed states, providing a clear chain of provenance for each asset without a central balance sheet. [25, 29]
Question 6: A consortium of four organizations (A, B, C, D) is operating a Hyperledger Fabric network. A specific chaincode requires that for any transaction to be valid, it must be approved by at least one organization from the pair (A, B) AND organization C. Which Fabric mechanism is used to formally define and enforce this rule before a transaction is committed to the ledger?
- A Membership Service Provider (MSP) policy
- A channel access policy
- An endorsement policy (Correct answer)
- An Access Control List (ACL)
Correct answer: An endorsement policy
An endorsement policy is defined for a chaincode and specifies which peers, and by extension which organizations, must execute and sign a transaction to deem it valid. [27] The policy can define complex rules, such as `AND(OR('A.member', 'B.member'), 'C.member')`, which directly implements the scenario described. This check is performed by committing peers before a block is written to the ledger. [22]
Free Certified Blockchain Professional (CBCP) Enterprise Blockchain Platforms Questions and Answers
A consortium of competing manufacturers wants to build a supply chain solution on Hyperledger Fabric.
They need to share transactional data with their direct suppliers and logistics partners, but want to ensure that pricing and quantity details remain confidential from other competing manufacturers on the same network.
Which Hyperledger Fabric feature is specifically designed to address this requirement?