CBP - Certified Bitcoin Professional Fundamental Cryptography Concepts Questions and Answers

Question 1

In the context of Bitcoin's public-key cryptography, which of the following statements accurately describes the relationship between a private key, a public key, and a Bitcoin address?

Accepted Answer

A Bitcoin address is a hashed version of the public key, which is mathematically derived from the private key.

Answer

The foundational principle of Bitcoin's cryptography is that a private key is generated first. From this private key, a corresponding public key is derived using Elliptic Curve Cryptography. The public key is then put through hashing algorithms (SHA-256 and RIPEMD-160) to produce the public Bitcoin address that is shared to receive funds.

Question 2

A user wants to send a Bitcoin transaction. To prove they are the legitimate owner of the funds, they must create a digital signature. Which cryptographic component is used to create this signature?

Accepted Answer

The user's private key

Answer

A digital signature in Bitcoin is created by signing the hash of the transaction data with the sender's private key. This proves ownership of the funds being spent without revealing the private key itself. Others on the network can then use the sender's public key to verify that the signature is valid.

Question 3

Which characteristic of a cryptographic hash function is most critical for ensuring the immutability of the Bitcoin blockchain?

Accepted Answer

Pre-image resistance

Answer

Pre-image resistance means it is computationally infeasible to find an input that hashes to a specific output. For the blockchain, this means it's practically impossible to alter a block's data without changing its hash. Since each block's hash is included in the subsequent block, changing a historical block would require re-mining that block and all subsequent blocks, which is computationally infeasible. This property directly contributes to the blockchain's immutability.

Question 4

A Bitcoin user has a 12-word mnemonic seed phrase. What is the primary function of this phrase in relation to cryptographic keys?

Accepted Answer

It is used to deterministically generate all private keys in a hierarchical deterministic (HD) wallet.

Answer

A mnemonic seed phrase, as defined by standards like BIP39, is a backup mechanism. It is used as a seed to a deterministic algorithm that can recreate the master private key, and from there, all the public/private key pairs within the wallet. This allows a user to restore their entire wallet on a new device with just the seed phrase.

Question 5

In asymmetric cryptography (also known as public-key cryptography), which key is kept secret and which is shared?

Accepted Answer

The private key is kept secret, and the public key is shared.

Answer

The core principle of asymmetric cryptography is the use of a key pair: a private key, which must be kept secret by the owner, and a public key, which can be freely distributed. Data encrypted with the public key can only be decrypted by the corresponding private key, and a signature created with the private key can be verified with the public key.

(CBP) Certified Bitcoin Professional Practice Test

(CBP) Certified Bitcoin Professional Practice Test

CBP - Certified Bitcoin Professional Fundamental Cryptography Concepts Questions and Answers