Are 128-bit symmetric keys really secure against quantum computers?

· Guillaume Kerkour · July 21, 2026, 8:54 a.m.
Security Cryptography Quantum Computing Encryption Algorithms
Summary
This blog post challenges a conclusion about the security of 128-bit symmetric keys against quantum computers, arguing that the prevailing opinion may be incorrect and comparing 128-bit vs 256-bit key sizes in AES encryption.
Read full post on kerkour.com →
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