Cryptography and Security Flashcards
7 cards from real CBCP practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Cryptography and Security flashcards as text
What is the Schnorr signature scheme's key advantage over ECDSA in blockchain contexts?
Answer: It natively supports signature aggregation, allowing multiple signatures to be combined into one
Schnorr signatures support linear aggregation (e.g., MuSig), enabling multiple signers to produce a single compact signature, improving scalability and privacy.
In symmetric encryption used for blockchain data at rest, what is the fundamental limitation compared to asymmetric encryption?
Answer: It requires a secure channel to share the secret key between parties
Symmetric encryption requires both parties to already share a secret key, making initial key exchange the central security challenge.
What is a Pedersen commitment, and where is it commonly used in blockchain privacy?
Answer: A homomorphic commitment scheme allowing arithmetic on hidden values, used in confidential transactions
Pedersen commitments are computationally hiding and perfectly binding; their homomorphic property allows verifying transaction balance without revealing amounts, as in Confidential Transactions.
What does 'perfect forward secrecy' (PFS) mean in the context of blockchain node communications?
Answer: Past session keys cannot be compromised even if the long-term private key is later revealed
PFS ensures that session keys derived from ephemeral key exchanges remain secure even if the server's long-term private key is later compromised.
How does a ring signature in Monero provide sender anonymity?
Answer: It allows a signer to sign on behalf of a group without revealing which group member actually signed
Ring signatures let one member of a group (ring) sign a message such that any ring member could plausibly be the signer, providing sender ambiguity.
What is the difference between a hot wallet and a cold wallet from a cryptographic security standpoint?
Answer: Hot wallets keep private keys connected to the internet; cold wallets keep keys fully offline
The key distinction is internet exposure: hot wallets have keys accessible online (higher convenience, higher risk), while cold wallets keep keys air-gapped offline.
What cryptographic primitive underlies atomic swaps between different blockchains?
Answer: Hash Time-Locked Contracts (HTLCs) using SHA-256 preimage secrets
Atomic swaps use HTLCs where funds are locked with a hash and can only be claimed by revealing the preimage within a time window, enabling trustless cross-chain exchange.