International Journal of Applied Cryptography (3 papers in press)

Regular Issues

• BlockFedL: a blockchain-based federated learning framework for securing smart UAV delivery systems at the edge  
  by Chengzu Dong, Zhiyu Xu, Shantanu Pal, Frank Jiang, Shiping Chen, Chong Zhang, Xiao Liu 
  Abstract: The integration of edge computing into advanced UAV delivery systems is of great interest to both research and industry. This integration offers new business opportunities and serves as a testbed for innovative technologies like edge computing, blockchain, and machine learning. A key concern for these systems is data privacy, especially given the large amounts of user and UAV data processed for tasks such as self-guided navigation, facial recognition, and person re-identification (ReID). To address this, federated learning (FL) has emerged as a popular choice, allowing for model parameter sharing while keeping raw data private. However, traditional FL approaches are vulnerable to single points of failure. Our study introduces the blockchain-powered edge FL (BlockFedL) framework, a blockchain-enhanced, decentralised FL framework for edge-based UAV delivery systems. BlockFedL leverages blockchain to form a decentralized FL network, ensuring secure data storage and mitigating risks. We specifically investigate privacy issues in the person ReID application for smart UAV delivery systems and introduce a proof of quality factor (cPoQF) consensus protocol to address blockchain scalability challenges. Experimental results demonstrate improvements in energy consumption, transaction speed, and processing capacity, highlighting the frameworks effectiveness.
  Keywords: UAV delivery; blockchain technology; internet of things; IoT; edge computing; collaborative learning; federated learning; intelligent communications.
  DOI: 10.1504/IJACT.2024.10065181
   
  
• Private set intersection with constant-size encryptions using RSA subgroups  
  by Sigurd Eskeland 
  Abstract: Private set intersection (PSI) evaluation is a well-known secure multiparty computation problem that has received much attention. Authors generally tend to state improved performance as a goal and justification for their proposed PSI schemes. In this paper, we propose an original and new approach to two-party PSI evaluation based on RSA subgroups. The novel idea aims at that each element and subgroups of a universe can be represented by means of subgroups having unique order. Moreover, this representation enable any subset within that universe can be encrypted by a single encryption, and not by many individual encryptions. The proposed protocols combine the private inputs of two parties securely, in such a way that all that can be deduced from the resulting subgroup is whether the inputs overlap or not. Contrary to previous approaches that at best incur linear communication and computational complexity to the set size, our scheme is the first to achieve constant communication and computational complexity incurring only two encryptions and five exponentiations. Configurations for three output granularities (Boolean, cardinal, and intersection subset) are proposed. Lastly, an extended PSI scheme handling larger sets is also proposed.
  Keywords: private set intersection; secure multiparty computations; RSA subgroups.
  DOI: 10.1504/IJACT.2024.10067208
   
  
• Cryptanalysis of Markle-Hellman knapsack cipher using nature inspired algorithms  
  by Subinoy Sikdar, Joydeep Biswas, Malay Kule 
  Abstract: In this paper, cryptanalysis of Markle-Hellman Knapsack cipher is demonstrated using nature inspired algorithms. The attack methods were implemented using three different algorithms on the same Knapsack cipher. The cryptanalytic attack algorithms are proposed based on Cuckoo Search Algorithm (CSA), Grey Wolf Optimization (GWO) and the Harris-Hawk Optimization (HHO) technique. Chosen Plaintext Attack (CPA) has been executed using these attack algorithms to recover the plaintext. While executing these experiments, we also found out fascinating properties of these different nature inspired algorithms according to their working strategies. Comparatively a better experimental result has been obtained from the Harris Hawk Optimization technique, though test results attained from Cuckoo Search Algorithm and the Grey Wolf Optimization method are also very satisfactory. The reasons behind the better performance of HHO over GWO and CSA is also explained from the experimental results. This paper also presents the results comparisons with other existing similar works.
  Keywords: cryptanalysis; knapsack cipher; cuckoo search algorithm; CSA; grey wolf optimisation; GWO; Harris Hawk optimisation; HHO; nature inspired optimisation algorithms; Friedman test.
  DOI: 10.1504/IJACT.2024.10067627