Sürdürülebilir Kalkınma Amaçları
Yayınlar
- MakaleAçık Erişim2026Scopus SJRQ1Real-time photovoltaic voltage data-driven dynamic green s-box generation framework for smart grid security
Aydın, Yılmaz; Garipcan, Ali Murat; Özkaynak, Fatih
In this study, a dynamic substitution box (s-box) generation method is proposed using real-time voltage data obtained from photovoltaic (PV) panels as an environmentally sensitive entropy source. These data, affected by environmental conditions such as solar radiation and temperature, exhibit irregular and unpredictable temporal behavior, offering strong potential for cryptographic randomness generation. In this context, the 0–1 test, Kolmogorov Entropy (KE), scale-index analysis, and the National Institute of Standards and Technology (NIST) SP 800-22 test suite are applied to PV voltage data collected at 1-minute intervals, experimentally confirming their chaotic dynamics and high-entropy characteristics. Following appropriate preprocessing and nonlinear mathematical transformations, the validated data are utilized to generate 8-bit s-box structures. The cryptographic strength of the generated s-boxes is quantitatively evaluated using standard security metrics, including nonlinearity (NL), Differential Probability (DP), Linear Probability (LP), Strict Avalanche Criterion (SAC), and Bit Independence Criterion (BIC). The findings reveal that PV data can serve as a functional resource not only for energy monitoring but also for randomness-based cryptographic construction. This approach enables lightweight cryptographic solutions for resource-constrained edge devices requiring <1 KB of memory and supports context-aware data security in renewable energy infrastructures.
- MakaleAçık Erişim2025Scopus SJRQ1A novel s-box generation method based on metastable inducing over FPGA for block ciphers
Garipcan, Ali Murat; Aydın, Yılmaz; Özkaynak, Fatih
Substitution boxes (s-boxes) providing the nonlinearity property are fundamental components of modern encryption systems. The security of these systems directly depends on the quality of the s-boxes ensuring a high level of resistance to advanced attacks. Although there is no perfect method in the literature, improving the cryptographic properties of s-boxes, such as nonlinearity and differential independence remains an important area of interest for many researchers. In this paper, we propose a new s-box generation method based on the reinforcement of the randomness obtained from the metastable states of the R-S latch. In the proposed method, a Field Programmable Gate Array (FPGA) chip is used to obtain design inputs based on physical reality obtained from the hardware level. Design inputs with poor statistical adequacy are transformed into s-boxes by passing them through four different hash functions (Blake2b, Blake2 s, SHA3 and Shake). A total of 333,328 s-boxes are generated with the proposed method for four different scenarios and widely used evaluation metrics such as bijectivity, nonlinearity (NL), strict avalanche criteria (SAC), bit independence criteria (BIC), differential probability (DP) and linear probability (LP) are considered for the analysis. Taking into account these metric values, the study also presents a detailed performance comparison of the proposed s-boxes with recent studies from the last 5 years in the literature. The fact that the nonlinearity degree of 75 % of the produced s-boxes is higher than 103, which is the average limit value in the literature, also confirms the method's efficiency, proven reliable by the analysis results. When all these results are evaluated together, they confirm that the proposed method is highly effective in generating robust s-boxes and that these s-boxes can be reliably used in modern cryptographic systems.
AtıfScopus21WoS23
İncele - MakaleAçık Erişim2025Scopus SJRQ1A novel post-processing approach for improving minimum nonlinearity in S-boxes: A case study based on 2D hyper chaotic Schaffer transformation map
Aydın, Yılmaz; Garipcan, Ali Murat; Özkaynak, Fatih
Substitution boxes (s-boxes), providing nonlinearity in block cipher algorithms, constitute a fundamental security layer against linear and differential cryptanalysis attacks. In this study, an innovative s-box generation method is proposed by integrating a 2D hyper-chaotic Schaffer map (SM) with biomolecular DNA-based encoding techniques. Furthermore, to enhance the security of s-box structures, a novel post-processing algorithm is developed, aiming to simultaneously optimize both the average (NLavg) and minimum (NLmin) nonlinearity levels by targeting linear components. Unlike traditional meta-heuristic methods, the proposed algorithm avoids random exploration across large search spaces, instead identifying dominant linear components through Walsh spectrum analysis and applying targeted permutation operations to suppress their effects. This strategy not only increases the NLavg value but also balances the contribution of each Boolean function to security, thereby establishing a homogeneous and consistent security structure across all input–output combinations. Comparative experimental analyses with existing methods demonstrate that the proposed approach outperforms prior techniques in terms of both cryptographic security metrics and computational efficiency. In this respect, the study presents an advanced s-box design framework, characterized by high nonlinearity and a balanced spectral distribution, suitable for integration into modern block cipher systems.
AtıfScopus12WoS13OpenAlex13İncele - Proje2021Kaotik Entropi Kaynakları Ve Optimizasyon Algoritmaları Kullanılarak Gürbüz Anahtar Üreteçlerinin Tasarımı Ve Mobil Platformlar Için Pratik Uygulamalarının Geliştirilmesi
Özkaynak, Fatih; Bürhan, Yücel; Aydın, Yılmaz; Durmuş, Beyzanur; Çakıl, Ahmet Can; Metin, Zülfiye Beyza; Kaya, Ömer
Son yirmi yılda, kaos temelli şifreleme, kaotik sistemlerin pratik uygulamaları arasında en dikkat çekici konulardan biri olmuştur. Literatürde binlerce çalışma vardır. Ancak bu çalışmalar incelendiğinde iki temel kategori ön plana çıkmaktadır. Birinci kategorideki çalışmalar kaotik sistemlerin zengin rastgelelik dinamiklerini kullanan yeni şifreleme protokollerini önerirken, ikinci kategorideki çalışmalar ise bu ilk kategoride önerilenlerin güvenlik zayıflıklarını analiz etmektedir. Bu iki karşıt durum birçok araştırmacının kaos temelli kriptolojiye şüphe ile yaklaşmasına neden olmaktadır. Proje önerisinde bu problemleri adresleyebilmek için kaotik sistemlerin rasgelelik karakteristiklerin optimizasyon algoritmaları yardımıyla iyileştirilmesi, fiziksel klonlanamaz fonksiyonlar ve çeşitli son işlem teknikleri ile elde edilen çıktıların görüntü şifreleme algoritmasına dönüştürülmesi planlanmıştır. Proje sonunda iki farklı fiziksel klonlanamaz fonksiyon kullanılarak önerilen görüntü şifreleme mimarinin hem masaüstü hem de mobil versiyonları gerçekleştirilmiştir. PUF donanımlarının kriptolojik uygunluğunun incelenmesi, kaotik yer değiştirme kutusu yapılarının yan kanal analizlerine karşı direncinin araştırılması ve kaotik entropi kaynaklarına çeşitli son işlem teknikleri uygulanarak kriptolojik açıdan daha başarılı tasarımlar elde edilebileceğinin gösterilmiş olması proje önerisinin diğer önemli çıktılarıdır. Tüm bu çıktılar kapsamında bir yüksek tezi, yüksek etki faktörlü iki araştırma makalesi ve bir uluslararası konferans bildirisi yayınlanmıştır. Proje sonuçları TÜBİTAK 1001 ve 1005 projelerine ön çalışma çıktısı olarak katkı sunmuştur.
