Cryptocurrency Cryptography and Hashing 2

Question 1

What property of a cryptographic hash function ensures that even a tiny change in input produces a completely different hash output?

Accepted Answer

Avalanche effect

Answer

The avalanche effect means a single-bit change in input dramatically alters the output hash, preventing partial-match attacks.

Question 2

Which elliptic curve does Bitcoin use for its public-key cryptography?

Accepted Answer

secp256k1

Answer

Bitcoin uses the secp256k1 elliptic curve, defined over a 256-bit prime field, to generate key pairs.

Question 3

What is a 'Merkle root' in the context of a Bitcoin block?

Accepted Answer

A single hash summarizing all transactions in a block

Answer

The Merkle root is a single hash derived by repeatedly hashing pairs of transaction hashes until one root hash remains.

Question 4

In asymmetric cryptography, which key is used to encrypt data intended for a specific recipient?

Accepted Answer

The recipient's public key

Answer

Data is encrypted with the recipient's public key, and only the recipient's matching private key can decrypt it.

Question 5

What does 'SHA' stand for in the context of Bitcoin's SHA-256 algorithm?

Accepted Answer

Secure Hash Algorithm

Answer

SHA stands for Secure Hash Algorithm, a family of cryptographic hash functions published by NIST.

Cryptocurrency Practice Test