Free Certified Blockchain Professional (CBCP) Blockchain Core Concepts Questions and Answers — Questions and Answers
Question 1: Which of the following best describes the principle of decentralization in blockchain technology?
- A single server is responsible for validating all transactions and maintaining the ledger.
- Control and decision-making are distributed across a peer-to-peer network of participants. (Correct answer)
- A government-appointed body regulates the network and approves new blocks.
- Transactions are processed by a central financial institution before being added to the chain.
Correct answer: Control and decision-making are distributed across a peer-to-peer network of participants.
Decentralization is a core concept of blockchain, meaning there is no central authority. Instead, control and data are distributed among the network's participants (nodes), who collectively validate transactions and maintain the ledger. This removes single points of failure and makes the network resistant to censorship and manipulation.
Question 2: A development team is building a decentralized application for supply chain management. They need a mechanism to ensure that all participants agree on the validity and order of transactions without a central intermediary. Which blockchain component fulfills this requirement?
- Cryptographic Hash
- Public Key Infrastructure
- Smart Contract
- Consensus Mechanism (Correct answer)
Correct answer: Consensus Mechanism
A consensus mechanism is the protocol that allows nodes in a distributed network to agree on the state of the ledger. It ensures that all valid transactions are recorded and that all participants have an identical copy of the ledger, which is crucial for a trustless environment like a supply chain application.
Question 3: What is the primary function of a cryptographic hash in linking blocks together to form a blockchain?
- To encrypt the transaction data within the block, making it unreadable to unauthorized parties.
- To generate a unique, fixed-length 'fingerprint' of the previous block's header, creating a secure and immutable chain. (Correct answer)
- To digitally sign transactions, proving the identity of the sender.
- To define the rules of the network, such as block rewards and transaction fees.
Correct answer: To generate a unique, fixed-length 'fingerprint' of the previous block's header, creating a secure and immutable chain.
Each block in a blockchain contains the cryptographic hash of the previous block's header. This hash acts as a unique identifier or 'fingerprint'. Because each block references the hash of the one before it, a secure and tamper-evident chain is created. Any change to a previous block would alter its hash, which would break the link to all subsequent blocks.
Question 4: In the context of blockchain, what is the relationship between a user's private key and public key?
- The public key is used to generate the private key.
- The private key and public key are identical and can be used interchangeably.
- The private key is mathematically derived from the public key and must be kept secret.
- The public key is mathematically derived from the private key and can be shared freely. (Correct answer)
Correct answer: The public key is mathematically derived from the private key and can be shared freely.
In public-key cryptography, a private key is generated first. A one-way mathematical function is then used to derive a corresponding public key from the private key. The private key must be kept secret as it is used to sign transactions and prove ownership, while the public key can be shared with others to receive funds.
Question 5: An organization wants to automate the payment of an insurance policy. The policy should automatically pay out a claim to a farmer if a trusted external weather data source reports a drought. Which blockchain concept would be most suitable for implementing this?
- Proof-of-Work
- Merkle Tree
- Smart Contract (Correct answer)
- Cold Storage
Correct answer: Smart Contract
A smart contract is a self-executing contract with the terms of the agreement directly written into code. It can automate actions based on predefined conditions. In this scenario, a smart contract could be programmed to execute a payment (the action) when it receives data from a trusted source (an oracle) indicating a drought has occurred (the condition).
Question 6: Which of the following is a key component of a block header in a typical blockchain?
- A list of all user public keys on the network.
- The hash of the previous block. (Correct answer)
- The complete code of all smart contracts.
- The private keys of the transacting parties.
Correct answer: The hash of the previous block.
A block header contains metadata about the block. One of its most critical components is the hash of the previous block (also called the parent block hash). This hash is what links the current block to the preceding one, forming the chronological and immutable chain.
Free Certified Blockchain Professional (CBCP) Blockchain Core Concepts Questions and Answers
Which of the following best describes the principle of decentralization in blockchain technology?