Network Attacks and Defenses
12 min readarticleIncludes quiz · 5 questions
To attack Bitcoin, you would need to control more than half of all mining power on earth — currently requiring billions of dollars in hardware and millions of dollars per day in electricity. And even then, you could only disrupt new transactions, not steal existing coins.
Learn about potential attacks on the Bitcoin network and how the protocol defends against them.
Attack Vectors:
- •51% Attack: Control majority hashrate
- •Double Spend: Spend same coins twice
- •Sybil Attack: Create many fake nodes
- •Eclipse Attack: Isolate nodes
- •Selfish Mining: Withhold blocks
- •Time Warp Attack: Manipulate timestamps
Defense Mechanisms:
- •Proof of Work: Makes attacks expensive
- •Decentralization: No single point of failure
- •Checkpoints: Prevent deep reorganizations
- •Peer Diversity: Multiple node connections
- •Economic Incentives: Honesty more profitable
- •Time Limits: Timestamp validation rules
Key Takeaway
The cost of attacking Bitcoin increases every year as the network grows. The economic incentive structure ensures that participating honestly is always more profitable than attacking.
Test Your Knowledge
5 questions · Passing score: 80%
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