Optimal Broadcast Encryption and More from Evasive LWE

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" summary

New construction gives ciphertext-policy ABE and optimal broadcast encryption from a new lattice hypothesis called evasive LWE plus standard LWE (subexponential modulus ratio). It removes pairings for the broadcast case by using a matrix vectorization identity, Gaussian trapdoors and short public R matrices; for low-norm A the scheme achieves polylogarithmic (optimal) public/ciphertext size in N and the construction is proven secure under evasive LWE, while full CP‑ABE requires an extra gadget-type assumption.

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" chapters (9)

1. 0:00Introduction to ABE
2. 2:24Prior work and limitations
3. 6:17Basic scheme construction
4. 10:43Handling collusion resistance
5. 16:04Security analysis and proofs
6. 22:58Optimal broadcast encryption
7. 26:54Evasive LWE assumption
8. 37:24Final construction refinement
9. 39:47Conclusion and open problems

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