iO via Functional Encryption: Techniques and Challenges from LWE

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" summary

Attempts to get functional encryption from LWE alone produce concrete partial results and clear roadblocks: constructions use homomorphic LWE encodings and dual‑Regev style keys to build noisy linear FE, but security holds only in restricted games or for one ciphertext because of leaky LWE keys that combine into SIS trapdoors. Overcoming noise requires degree flattening and structured LWE labels to generate compressed smudging noise; this yields plausibility under new interactive assumptions and non‑interactive security only in the single‑ciphertext case.

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" chapters (16)

1. 0:00Start
2. 2:47MC Escher
3. 3:31Hans Hoffman
4. 4:23Functional Encryption Encryption with Partial Decryption Keys
5. 7:01LWE...Leakage on Partial Decryption (FE)
6. 9:45Decryption works
7. 10:08We need: Partial Decryption Capability
8. 19:59Doing Without Pairings?
9. 27:27Degree Flattening
10. 30:17Symmetric key FHE for Quadratic Polynomials BV11a
11. 31:09FHE Evaluation
12. 34:53Compactness Vs Leakage
13. 41:55RLWE with Structured Noise
14. 45:33Security
15. 46:44Connection with Functional Encodings ww! • Functional encodings are akin to functional encryption with single ciphertext
16. 49:35Open Problems

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