Decentralized storage platforms and blockchain systems offer novel opportunities for data exchange; however, they also present significant challenges in safeguarding sensitive visual information. The Interplanetary File System (IPFS) offers efficient distributed storage, but it lacks built-in confidentiality mechanisms, making additional security layers necessary. This work proposes a security-oriented framework that integrates (k,n) threshold visual cryptography (shamir secret ), LSB-based image steganography, and blockchain-based ownership management using non-fungible tokens (NFTs). Sensitive images are divided into multiple visual shares using a threshold scheme so that no useful information can be obtained unless enough shares are available. Each share is then hidden inside a cover image using a simple LSB-based steganography method and stored on IPFS. Instead of storing the data itself on the blockchain, NFTs are used only to reference the stored content and record ownership in an immutable manner. Experimental results are evaluated using common image quality and statistical metrics, including PSNR, SSIM, correlation, and entropy. With PSNR = Inf dB for all images, Entropy analysis shows that the entropy values of the original cover images are approximately 7.0865, while the entropy values of the stego-images after embedding range between 7.0907 and 7.0954, indicating only a slight increase in randomness. This minimal change confirms that the LSB-based steganographic embedding does not significantly alter the statistical properties of the cover images. The findings show that the original images can be reconstructed with acceptable visual quality while preserving the statistical characteristics of the cover images. The proposed approach demonstrates that combining visual cryptography with decentralized storage and blockchain-based ownership can offer improved confidentiality compared to direct on-chain image storage, without introducing excessive system complexity.
Open access
Advanced Steganography and Watermarking Techniques
Mohammad Adel El Sehayl, Ahmad Almaaz, Khaleel Mershad, Nadine Abbas
The Interplanetary File System (IPFS) is a decentralized peer-to-peer (P2P) protocol for distributed file storage and sharing. It is one of the main pillars towards reaching the Web3 technology, which depends heavily on decentralization. IPFS ensures more control over stored data even across untrusted nodes. However, IPFS lacks various security measures, such as encryption, to ensure the confidentiality of the stored data. This paper suggests a parallel encryption engine incorporated within IPFS to enhance data security while maintaining high performance and speed. The paper specifically proposes a novel parallelized symmetric encryption framework that encrypts data chunks before distributing them across the IPFS network. Also, the engine uses hardware-accelerated instructions to ensure speedup and robustness. Various factors were considered to evaluate the research contributions, such as encryption speed, storage overhead, and retrieval efficiency. The obtained results signify the importance of incorporating encryption into IPFS to ensure data privacy without compromising performance. Furthermore, unauthorized access and data leakage can be prevented through encryption, enabling IPFS to become more suitable for sensitive data storage in decentralized environments. In general, the contributions of this research support the advancement towards Web3 by protecting usersâ data without aggravating the IPFS system efficiency and performance.
Modern cryptographic primitives have evolved from supporting basic to more advanced functionalities, and such schemes are now getting more practical. In this thesis, we identify and rectify some limitations of such cryptographic constructions and their proofs of security. Specifically, we work with functional encryption, secure aggregation, and threshold signature schemes, and observe key functional or security limitations in prior work. Our first focus is functional encryption (FE), which enables function evaluation on encrypted messages using a functional secret key. A different primitive named function-revealing encryption (FRE) allows one to compute a fixed function of the underlying messages using their ciphertexts only. We give formal definitions and construct an inner-product FRE scheme. We also analyze the relationship between FE and FRE. Our second contribution considers secure aggregation, a classic problem that has numerous applications in privacy preserving machine learning. Secure aggregation lets many clients contribute data for aggregation without revealing their individual data. Existing practical protocols either have multiple rounds of interaction between clients and the server or rely on heavyweight cryptographic primitives. We build a non-interactive secure aggregation protocol using a novel combination of inner-product FE and a fully-linear probabilistically checkable proof (FLPCP) system. For this protocol, we use an existing FLPCP system [BBCGIâ19] that we prove satisfies soundness and zero-knowledge properties even when reused for multiple proof instances. Finally, we address a pressing open question: achieving fully adaptive security for the Sparkle+ [CKMâ23] threshold signature scheme. Threshold schemes require t signers to provide partial signatures to form a valid one. Fully adaptive security prevents adversaries from forging signatures even when corrupting up to t-1 signers. While Sparkle+ is secure against static corruption and a limited number of adaptive corruptions, a previous proof of fully adaptive security was shown to be incorrect. We propose a novel hardness assumption under which Sparkle+ satisfies this notion with a tight reduction. We establish hardness of this assumption in the elliptic-curve generic-group model. Our contributions close important gaps in prior work and push advanced cryptographic primitives closer to practice.
Vinod Kumar Joshi, Rajendra Kachhava, Kriti Kamal Gupta, Dixit Dutt Bohra
The quantum-secure CBIR scheme which is presented in this research is a fence against unauthorized users and adversarial attacks on cloud environment remote sensor images. The proposed solution is characterized by Quantum Key Distribution, zero-knowledge proof authentication, QCrypt encryption, adversarial trained deep hashing, and robust watermarking. The model was developed with the help of the MLRSNet dataset, where proposed model recorded a remarkable mean average precision of 94.77% that is 10% improvement from the previous deep-hash results while the watermark-extraction accuracy of over 95% was maintained at 35 dB PSNR. The model has been able provide good result with adversarial, replay, and JPEG compression. Even though the computing engine provides military-grade security and forensic accountability, the current compute overhead is the major reason it has limited use in real-time scenarios.
In the digital era, protecting visual content from misuse and forgery is essential. This study proposes a robust image watermarking method by integrating Discrete Wavelet Transform (DWT), Hessenberg Decomposition (HD), and Singular Value Decomposition (SVD), aiming to enhance watermark imperceptibility and resilience against common image attacks. Additionally, the system incorporates RSA digital signatures within the watermark metadata to ensure verifiable authenticity in NFT (Non-Fungible Token) applications. The method was implemented using Python and tested on multiple grayscale images across various attack scenarios, including noise addition and compression. Experimental results demonstrate high SSIM and PSNR values, confirming the method's effectiveness in maintaining both visual fidelity and embedded watermark integrity. These findings support the potential of this approach for secure and scalable NFT copyright protection.
Open access
Advanced Steganography and Watermarking Techniques
This thesis deals with investing in the cryptocurrency market. The main objective of the thesis is to determine the most suitable investment strategy based on historical data and analysis. The theoretical part is devoted to the introduction of cryptocurrencies, technologies associated with cryptocurencies, legal regulations, and the use of cryptocurrencies as a means of payment. In the practical part, the weak-form efficiency of the cryptocurrency market is first tested using the Wald-Wolfowitz runs test. Subsequently, the investment strategies Buy and Hold, Dollar Cost Averaging (DCA), moving average crossovers, and an equally weighted portfolio are compared. These strategies are evaluated using returns, volatility, Maximum Drawdown, and the Sharpe ratio. For comparison with more traditional markets, external benchmarking with the S&P 500 equity index is conducted.
Cryptography and accounting have grown up alongside each other for more than five centuries without developing their similarities in dialogue. This extended concept note outlines a vision for a crossdisciplinary research programme integrating six philosophical dimensions: ontological, epistemological, axiological, teleological, praxiological and phenomenological. It explicates only the structural (ontological) dimension in detail, arguing that asymmetric verifiability (whereby the cost of engineering a false acceptance is deliberately set to exceed the cost of verifying a true one) is foundational to both disciplines: in cryptography to one-way functions, digital signatures and zero-knowledge proofs, and in accounting to conservatism in the Basu (1997) and Watts (2003) tradition. The remaining five dimensions are stated concisely and anchored to established literature on each side, with the lived practice of each craft identified as the least studied and the clearest opening for joint work, particularly in the context of post-quantum cryptography (PQC). The present contribution is the naming of the six-dimension structure rather than local novelty within any single dimension; prior scholarship has already placed Albertiâs cryptography and Pacioliâs bookkeeping within a common Renaissance tradition addressing trust at a distance. The note develops a role-to-treatment taxonomy and worked ledger illustrations (a TLS certificate issuance and two distinct quantum exposures: harvest-now-decrypt-later and trust-now-forge-later), and closes with a call for collaboration between cybersecurity and accounting researchers.
Interoperation across distributed ledger technology (DLT) networks hinges upon the secure transmission of ledger state from one network to another.This is especially challenging for private networks whose ledger access is limited to enrolled members.Existing approaches rely on a trusted centralized proxy that receives encrypted ledger state of a network, decrypts it, and sends it to members of another network.Though effective, this approach goes against the founding principle of DLT, namely avoiding single points of failure (or single sources of trust).In this paper, we leverage fully-distributed broadcast encryption (FDBE in short) to build a fully decentralized protocol for confidential information-sharing across private networks.Compared to traditional broadcast encryption (BE), FDBE is characterized by distributed setup and key generation, where mutually distrusting parties agree on a BE's public key without a trusted setup, and securely derive their decryption keys.Given any FDBE, two private networks can securely share information as follows: a sender in one network uses the other network's FDBE public key to encrypt a message for its members.The resulting construction is secure in the simplified universal composability (UC) framework.To further demonstrate the practicality of our approach, we present the first instantiation of an FDBE that enjoys constantsized decryption keys and ciphertexts, and evaluate the resulting performances through a reference implementation that considers two private Hyperledger Fabric networks within the Hyperledger Cacti interoperation framework.
Consumer Healthcare Devices (CHD) in Healthcare 4.0 (HC 4.0) increasingly generate continuous physiological data that are transformed into 3-dimensional holographic visualizations for remote monitoring, diagnosis, and clinical decision support. However, existing IoMT and blockchain (BC)-based healthcare systems protect data storage and access but do not verify the integrity, freshness, or provenance of holographic patient representations, leaving such visualizations vulnerable to spoofing, replay, and slice-level tampering. This paper proposes a Blockchain-Assisted Holographic Counterpart (BAHC) framework that cryptographically binds wearable devices to holographic updates using PUF-derived Holographic Authentication Tokens (HAT), enforces slice-level integrity through a Merkle-Hologram-Commitment Tree (Merkle-HC Tree), and anchors updates on a permissioned Proof-of-Authority (PoA) BC. Privacy-preserving access control and verification are achieved using Ciphertext-Policy Attribute-Based Encryption (CP-ABE) and Zero-Knowledge Proofs (ZKPs). The framework is evaluated on a controlled experimental testbed emulating 500 concurrent patient streams using independent public physiological datasets and public MRI volumes for synthetic hologram generation, measuring end-to-end latency, anomaly detection performance, rendering efficiency, and blockchain throughput under up to 100 validators. Experimental results show a 68.6% reduction in holographic rendering latency, a 34% reduction in diagnostic latency, a relative 27% improvement in anomaly detection performance, and sustained throughput close to 500 transactions per second, demonstrating that BAHC provides a scalable and trustworthy foundation for secure holographic monitoring in HC 4.0 systems.
Chaos-based Image/Signal Encryption
Physical Unclonable Functions (PUFs) and Hardware Security
Prof. Abhijeet More, Tejashree B. Patil, Deep Kharate, M P Akhil · 5 authors
As the multi-chain digital assets, decentralized finance (DeFi) and non-fungible tokens (NFTs) seeing rapid development, cryptocurrency portfolio management is causing strong pain among users.With the growing number of blockchain networks like Ethereum and a variety of chains, users commonly have assets across multiple wallets, protocols and dApps.Classic portfolio tracking services often require the constant relationship between client and server, with centralized servers, offering heavy privacy issues and security implications.Manual and account based access Many of these systems require data to be manually entered or employees to sign in with their accounts, which opens up the possibility for data leaks, inaccurate reporting, and divulgence of sensitive financial information.More centralized trackers unfortunately have a very poor understanding of more advanced DeFi functions such as staking, joining liquidity pools, and yield farming positions, total or just plain token approval permissions leading to either incomplete or worse yet misleading asset summaries.To solve the above issues, this system suggests a completely decentralized cryptocurrency portfolio tracker on client-side.The code utilizes APIs like Alchemy, Zapper and CoinGecko to read real-time token balances, NFTs creatures or positions (for DeFi), and allowances from the current network directly offchain.Being exclusively client side, the tracker does not rely on centralized databases and it is designed to minimize privacy compromises.The built-in on-chain security module is its most noticeable feature, as it detects any potentially malicious or extremely large token approvals given to smart contracts.Suspicious approvals can be detected, and then revoked in a timely manner through signed wallet transactions without needing to reveal any private keys.The results show that this decentralized tracker would provide significantly better user privacy, data accuracy and overall security.As a serverless applications service, that bypasses central authentication, as well as database storage, it offers a transparency, user-centric and scalable way to manage digital assets securely.
Open access
Internet Traffic Analysis and Secure E-voting
Chaos-based Image/Signal Encryption
Advanced Steganography and Watermarking Techniques
Mohammad Javad Jannati, Abolfazl Iraninasab, Mehrshad Eskandarpour
As blockchain adoption accelerates, smart contracts have become attractive targets for attackers, often resulting in significant financial losses. While many studies focus on well-known vulnerabilities like reentrancy or integer overflows, weaknesses in pseudo-random number generation (PRNG) remain a persistent and critical challenge despite their role in decentralized applications such as lotteries, games, and token distribution. In Ethereum, randomness is often derived from predictable environmental variables like block timestamps or sender addresses, making these systems vulnerable to manipulation. This paper presents a rigorous investigation into PRNG vulnerabilities in Ethereum smart contracts and introduces two practical attack strategies. The first method relies on brute-force contract deployment to obtain a desired output, incurring high gas costs. The second approach leverages the CREATE2 opcode to precompute candidate contract addresses off-chain, reducing gas usage by over 90%. However, since final outcome prediction depends on block.timestamp at execution time, attack success is contingent on network timing stability and validator behavior. Through formal analysis and empirical evaluation on a controlled local test network, we demonstrate success rates of 100% for Method 1 and 98% for Method 2 under fixed-timestamp conditions. Under simulated live-network congestion, Method 2 success drops to 87% due to block.timestamp sensitivity. Our findings highlight the urgent need for secure randomness solutions, such as verifiable random functions (VRFs) and decentralized randomness beacons. Without adopting such mechanisms, blockchain applications across Ethereum and other EVM-compatible platforms remain exposed to critical security risks.
Rajasekaran P., Duraipandian M., Johny Renoald Albert, R. Jamuna · 5 authors
The Internet of Medical Things (IoMT) in the IoT with Cloud Healthcare (CHI) creates a high volume of realâtime medical data, but traditional compression methods suffer high computation costs, privacy leaks and quantum attacks, while advanced cryptographic algorithms such as homomorphic encryption are costly and have poor scalability for the realâtime system application. In this work, we propose a quantumâenhanced zeroâknowledge healthcare compression network (QZâHCN) that associates zeroâknowledge proofs (ZKPs) with quantumâinspired deep learning (QIDL) by introducing an innovative adaptive quantumâsupported ZKP verification mechanism (AQâZKV) and a quantum fusion autoconventional neural network (QFâAutoCNN) technique to achieve efficient, privacyâpreserving compression. For healthcare IoT datasets, QZâHCN can reach 98.16% in accuracy, 97.09% in Fâmeasure, 96.32% in precision and 97.45% in recall, with a throughput of 449.57 bits/s; processing time is reduced to 0.85 s, and memory cost is minimised to be only 192 kbits, which outperforms CNNâEncryption (90.23% accuracy), proxy reâencryption and homomorphic encryption by at most 13 percentage points in accuracy and 75 percentage points in memory efficiency. The secure and scalable management for CHI data is achieved by QZâHCN, which solves the problems of privacy threats and space costs of realâtime medical applications.