🛡️ Why Changing History Is Impossible
See how tampering with one block breaks the entire chain
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0 / 5 completed🛡️ Chain Integrity & Tampering
What happens when someone tries to tamper with a block? Let's explore why blockchain is considered "immutable" and tamper-proof.
🎯 The Challenge
Imagine a hacker wants to change a historical transaction. Maybe they want to increase the amount they received or delete evidence of a payment. Let's see what happens when they try.
Hacker's Goal:
Change "Bob → Charlie: 5 BTC" to "Bob → Hacker: 50 BTC"
Let's see if they can get away with it...
🔥 Tamper Simulation
Click "Tamper" on any block to see how it breaks the chain:
Block #1
Alice → Bob: 10 BTC
Hash:00000a5f
Prev Hash:Genesis
Block #2
Bob → Charlie: 5 BTC
Hash:00000b3c
Prev Hash:00000a5f
Block #3
Charlie → David: 3 BTC
Hash:00000c7d
Prev Hash:00000b3c
Block #4
David → Eve: 2 BTC
Hash:00000d8e
Prev Hash:00000c7d
🔐 Why Blockchain is Secure
1
Cascading Effect: Changing one block invalidates all subsequent blocks, making tampering obvious and requiring re-mining the entire chain.
2
Network Consensus: Even if you fix your copy of the chain, every other node has the correct version and will reject your tampered chain.
3
Computational Cost: Re-mining blocks requires massive computational power. The deeper in history a block is, the more work needed to tamper with it.
✅Valid Chain
- • All previous hashes match
- • No broken links
- • Every block verified
- • Network accepts the chain
❌Tampered Chain
- • Hash mismatch detected
- • Broken link in chain
- • Subsequent blocks invalid
- • Network rejects the chain