✅ You're Now a Cryptographic Hash Expert
Master collision resistance, birthday paradox, and why SHA-256 is still secure
Your Progress
0 / 5 completed🎓 Key Takeaways
📚 Core Concepts Mastered
When two different inputs produce identical hash outputs. Breaks the uniqueness guarantee of hash functions.
Finding collisions requires only √n attempts, not n. Makes collision attacks exponentially easier than expected.
Collision attacks (find ANY match), preimage attacks (find specific input), and second preimage attacks.
MD5 and SHA-1 broken. Trillions in digital assets depend on SHA-256 remaining collision-resistant.
💡 Practical Insights
Never use MD5 or SHA-1 for security. SHA-256, SHA-3, or newer algorithms are required for any cryptographic application.
Increasing hash size from 128 to 256 bits doesn't just double security - it makes collisions 18 quintillion times harder to find!
Bitcoin's entire security model relies on SHA-256 collision resistance. If broken, the $1.5T+ cryptocurrency market would collapse.
Attackers don't need to target a specific hash - they can generate many inputs and look for ANY collision. This is why hash size must be large.
📝 Test Your Knowledge
Answer these questions to verify your understanding: