A global payment system uses zero-knowledge proofs to hide transaction amounts. A regulator in one jurisdiction requires the ability to trace transactions for AML purposes, while another jurisdiction requires strict privacy with no tracing. Which approach best satisfies both jurisdictions?

Use a single global policy that prohibits tracing for all transactions.

Use a trusted third party to decide on a case-by-case basis.

Implement a multi-jurisdiction system with selective disclosure based on the jurisdiction of the transaction.

Use a single global policy that allows tracing for all transactions.

A supply chain consortium wants to run a smart contract that verifies a shipment's temperature stayed within a required range during transit, without revealing the actual temperature readings to competitors. The contract must be publicly verifiable. Which technique should be used?

Have the smart contract access an off-chain oracle that reveals the readings to the public

Use a hash of the temperature readings and store the hash on-chain

Store the temperature readings on-chain in an encrypted format and share the decryption key with all consortium members

Generate a zero-knowledge proof that the temperature readings satisfy the range condition, and submit the proof to the smart contract

A privacy-focused cryptocurrency wants to allow users to send transactions without revealing the sender, receiver, or amount. They also need to prevent double-spending. Which combination of technologies is most appropriate?

Ring signatures, stealth addresses, and confidential transactions

zk-SNARKs and Pedersen commitments

Ring signatures and stealth addresses

Merkle trees and digital signatures

What is a common regulatory challenge when implementing anonymous transactions in a blockchain?

Making the transaction data readable by all network participants.

Ensuring that law enforcement can trace transactions when required by law.

Preventing users from creating multiple identities.

Ensuring that the blockchain is fast enough to process anonymous transactions.

EC-CouncilBlockchain Developer Certification

Domain 9Objective 3

Privacy and Zero-Knowledge Innovations BDC Practice Questions (Page 7)

Part of the Advanced Concepts and Future Innovations domain, which makes up ~12% of our current practice bank.

38questions here

8free pages

5concepts

Questions 31–35

31expert · hard
A global payment system uses zero-knowledge proofs to hide transaction amounts. A regulator in one jurisdiction requires the ability to trace transactions for AML purposes, while another jurisdiction requires strict privacy with no tracing. Which approach best satisfies both jurisdictions?
Select an answer first
32application · medium
A supply chain consortium wants to run a smart contract that verifies a shipment's temperature stayed within a required range during transit, without revealing the actual temperature readings to competitors. The contract must be publicly verifiable. Which technique should be used?
Select an answer first
33application · medium
A privacy-focused cryptocurrency wants to allow users to send transactions without revealing the sender, receiver, or amount. They also need to prevent double-spending. Which combination of technologies is most appropriate?
Select an answer first
34foundation · easy
What is a common regulatory challenge when implementing anonymous transactions in a blockchain?
Select an answer first
35application · medium
A government agency is evaluating a zero-knowledge proof system for a public voting application. They require that the system be post-quantum secure and that no trusted setup ceremony be needed. Which proof system should they select?
Select an answer first

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