Why 128-bit Symmetric Keys Are Still Quantum-Resistant

Contrary to the widespread belief that quantum computing will render current encryption obsolete, 128-bit symmetric keys remain secure because Grover's algorithm cannot be efficiently parallelized. This means the transition to 256-bit keys is less urgent than theoretical models suggest, allowing engineers to focus on more immediate security vulnerabilities. It redefines the timeline for post-quantum cryptographic readiness for mainstream applications.