Quantum Implementation of S-Boxes: A Memory Optimized Approach


Tilki O., Saran A. N., ÇILDIROĞLU H. Ö., YAYLA O.

18th International Conference on Information Security and Cryptology, ISCTurkiye 2025, Ankara, Türkiye, 22 - 23 Ekim 2025, (Tam Metin Bildiri) identifier

  • Yayın Türü: Bildiri / Tam Metin Bildiri
  • Doi Numarası: 10.1109/isctrkiye68593.2025.11224820
  • Basıldığı Şehir: Ankara
  • Basıldığı Ülke: Türkiye
  • Anahtar Kelimeler: Memory Optimization, Quantum circuit, Quantum Computing, S-Box
  • Orta Doğu Teknik Üniversitesi Adresli: Evet

Özet

Substitution boxes (S-boxes) serve as fundamental non-linear components in symmetric cryptography, and their quantum circuit implementation is critical for quantum security. This work addresses the dual challenges of quantum circuit depth optimization and computational intractability in S-box synthesis. We introduce memory-optimized data structures, a pointer-efficient RandomAccessSet and a dynamic devector, that reduce memory overhead by 12 times per element, thereby mitigating the computational complexity associated with Pauli representation. Our enhanced Meet-in-the-Middle framework achieves exhaustive depth optimization for standardized S-boxes, demonstrating up to 8.5% depth reduction over DORCIS baselines at equivalent T-depth. The approach scales to 5-8-bit primitives, establishing memory efficiency as an independent resource dimension in quantum circuit synthesis. Comparative analysis under varied cost parameters provides new insights for resource-efficient cryptographic implementations on quantum hardware.