BBLOCKCHAIN MASTERYBCM · a One Great Mentor Mastery Track

Viva preparation

A viva is not recall. You must justify why a mechanism exists, what it costs and where it fails. Practise mode reveals reasoning; assessment mode does not.

BCM-C01 · Why Blockchain Exists

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Viva preparation

BCM-C01 · Why Blockchain Exists

1. What exactly is the double-spending problem?

2. Why can't we just timestamp transactions and take the earliest?

3. Does hashing make blockchain data impossible to change?

4. What does the 'CPU power as credential' idea actually mean?

5. What is a confirmation, and when is one enough?

6. Why is verification cheap but block production expensive?