Blockchain Papers

Ghassan Al-Sumaidaee, Željko Žilić

In an era dominated by rapid digitalization of sensed data, the secure exchange of sensitive information poses a critical challenge across various sectors. Established techniques, particularly in emerging technologies like the Internet of Things (IoT), grapple with inherent risks in ensuring data confidentiality, integrity, and vulnerabilities to evolving cyber threats. Blockchain technology, known for its decentralized and tamper-resistant characteristics, stands as a reliable solution for secure data exchange. However, the persistent challenge lies in protecting sensitive information amidst evolving digital landscapes. Among the burgeoning applications of blockchain technology, non-fungible tokens (NFTs) have emerged as digital certificates of ownership, securely recording various types of data on a distributed ledger. Unlike traditional data storage methods, NFTs offer several advantages for secure information exchange. Firstly, their tamperproof nature guarantees the authenticity and integrity of the data. Secondly, NFTs can hold both immutable and mutable data within the same token, simplifying management and access control. Moving beyond their conventional association with art and collectibles, this paper presents a novel approach that utilizes NFTs as dynamic carriers for sensitive information. Our solution leverages the immutable NFT data to serve as a secure data pointer, while the mutable NFT data holds sensitive information protected by steganography. Steganography embeds the data within the NFT, making them invisible to unauthorized eyes, while facilitating portability. This dual approach ensures both data integrity and authorized access, even in the face of evolving digital threats. A performance analysis confirms the approach's effectiveness, demonstrating its reliability, robustness, and resilience against attacks on hidden data. This paves the way for secure data transmission across diverse industries.

Zaman Nihat, Işıl Karabey Aksakalli, Nursena Bayğın

With the rise of digitalization and increased internet usage, digital certificates' security issues have gained significant importance. The utilization of counterfeit certificates can lead to deceptive identity and capability verifications, allowing untrustworthy individuals to assume misleading positions. Simultaneously, factors such as data leaks and technical glitches can jeopardize the security of certificates. These challenges can complicate talent verification processes and result in unsuitable individuals being placed in incorrect roles. The proposed work aims to thwart forged certificates and ensure their verifiability within this context. The methodology employed in the study strives to mitigate potential data loss or accessibility problems by adopting a decentralized storage structure. The primary objective is to establish certificates that are reliable, traceable, and capable of being verified. A rapid and efficient user interface was developed using React.js to achieve this aim. Smart contracts were scripted on the Ethereum blockchain using Solidity, and data, including user information and certificate details, were stored within components like MongoDB. In the phase of practical implementation, diverse scenarios have been designed to facilitate the generation, verification, and monitoring of certificates. The proposed approach is geared towards deterring forgery and enhancing the credibility of certificates. Through this system, users and organizations can authenticate certificates and prevent the proliferation of counterfeit ones. Furthermore, the enhanced security and ease of sharing certificates on digital platforms offer substantial advantages to certificate holders. In summary, this study strives to enhance the safeguarding and dependability of certificates by addressing the security concerns posed by the era of digitalization.

Mohammad Hajian Berenjestanaki, Hamid R. Barzegar, Nabil El Ioini, Claus Pahl

The employment of blockchain technology in electronic voting (e-voting) systems is attracting significant attention due to its ability to enhance transparency, security, and integrity in digital voting. This study presents an extensive review of the existing research on e-voting systems that rely on blockchain technology. The study investigates a range of key research concerns, including the benefits, challenges, and impacts of such systems, together with technologies and implementations, and an identification of future directions of research in this domain. We use a hybrid review approach, applying systematic literature review principles to select and categorize scientific papers and reviewing the technology used in these in terms of the above key concerns. In the 252 selected papers, aspects such as security, transparency, and decentralization are frequently emphasized as the main benefits. In contrast, although aspects like privacy, verifiability, efficiency, trustworthiness, and auditability receive significant attention, they are not the primary focus. We observed a relative lack of emphasis on aspects such as accessibility, compatibility, availability, and usability in the reviewed literature. These aspects, although acknowledged, are not as thoroughly discussed as the aforementioned key benefits in the proposed solutions for blockchain-based e-voting systems, whereas the considered studies have proposed well-structured solutions for blockchain-based e-voting systems focusing on how blockchain can strengthen security, transparency, and privacy, in particular, the crucial aspect of scalability needs attention.

João Beleza Sousa, Gonçalo Marques

Nothing prevents several Non Fungible Tokens (NFTs) to be associated to the same digital asset, for instance, an image. As a consequence, the NFTs ecosystem is flooded with NFT replicas associated to the same assets of famous NFTs. The purpose of this paper is to propose creating NFTs in such a way that NFT/asset combination can not be replicated. We call the NFTs created in this way, Authentic NFTs. NFT token ids are known in advance, before creating the NFTs. Our approach is to include the NFT token id in the digital asset, and have the asset being digitally signed by it’s creator (author/artist). Given that NFT IDs are unique, our main finding is that any Authentic NFT replica can not be authentic. Either the NFT replica id does not match the NFT ID in the asset (if the asset was not modified), or the NFT replica asset is not signed by the asset creator (if the asset was modified).

Mikhail Cherdakov, Aleksey Kudashkin, Yash Madhwal, Yury Yanovich

The music industry faces numerous challenges regarding tracking and distributing royalties. This article explores how a decentralized and transparent system for managing music royalties can be created with a smart contract implementation on the Polygon network, utilizing Chainlink oracles. By enhancing the efficiency and transparency of royalty distribution, this groundbreaking smart contract has the potential to revolutionize the music industry and stand as a blueprint for diverse sectors grappling with analogous challenges in intellectual property rights and revenue allocation. At its core, this smart contract, functioning on the bedrock of blockchain, ensures meticulous oversight of financial transactions between consumers and content creators. It streamlines the process and facilitates the collection of user view statistics crucial for strategic fund allocation. With the potential impact of transaction fees on the user experience of blockchain payments, a new solution has been developed that includes a payment channel that reserves significant amounts of funds and enables off-chain payments through specialized messages. By combining these technological advancements, we are taking a transformative step towards a more seamless and fair future in the complex world of royalty management. The application is structured into conventional backend and frontend segments, with the code available on Github.

Saeed Banaeian Far, Maryam Rajabzadeh Asaar

Blockchain technology has emerged as a compelling field of study over the past decade. Nevertheless, certain blockchain-based protocols, particularly those reliant on permissioned blockchains, continue to be under the governance of a central authority (CA). This central authority possesses extensive control capabilities, including the facilitation of user network access, as well as the establishment, connection, and revocation of users to and from the network. Consequently, the majority of policies within these protocols are centrally administered by a singular party. This paper introduces an architectural framework and a specific protocol denoted as the ”Anonymous Reporting System with No Central Authority” (ARSnCA) on a public blockchain infrastructure. This design aims to mitigate the challenges posed by untrusted privileged insiders to the ARSnCA. It is hypothesized that this approach can enhance system reliability, fault tolerance, and foster trust among network members. To eliminate the central authority, a concept termed the virtual blockchain (VBC) is implemented as an embedded permissioned blockchain within a permissionless blockchain. Following the removal of the CA, the authorities previously held by the central authority are transferred to the members of the VBC. Comparative analysis and evaluation of the ARSnCA protocol demonstrate a performance advantage, with speeds that are 62% and 92% faster than reporting protocols based on ring signatures and other protocols included in the comparison.

Mao Wang, Shanshan Tu, Haoyu Yu, P.Y. Yan

With the continuous development of Internet of vehicles (IoV) services and the continuous influx of network users, how to solve the security and user privacy protection problems of IoV system has become a top priority. In this regard, based on the in-depth analysis and research of the existing cryptographic theory and anonymous authentication scheme, aiming at the key issues in the security architecture of IoV based on blockchain technology, we propose an anonymous authentication scheme for IoV based on private blockchain. We design a private blockchain-based anonymous authentication scheme for IoV. With the help of the non-tampering characteristics of blockchain, through the decentralized and distributed public key infrastructure (PKI), the registration pressure under high load is effectively shared. In addition, based on the system architecture of distributed authentication, we also design the anonymous identity update stage of the vehicle through the form of hybrid chain, which realizes the continuous tracking and tamper resistance of the vehicle anonymous identity binding information. Finally, through the security analysis and the implementation of the simulation system, we prove that the scheme meets the security requirements and effectively improves the efficiency of the anonymous authentication process.

Mehak Zia, Muhammad Kamran, Naeem Aslam, Muhammad Fuzail

Smart contracts, a unique form of blockchain technology, enable financial transactions on the Ethereum blockchain. However, the blockchain paradigm's decentralized structure raises security concerns and has been linked to significant financial losses. Contrary to typical financial entities, Ethereum lacks centralized controls to solve these challenges. These problems have been addressed and Ethereum's security has been enhanced by symbolic execution, which has grown to be a well-known technique for guaranteeing programme integrity. The security of the blockchain can be improved more efficiently by using this method to assess Ethereum's security and identify areas that require the attention of security experts.

Zhonghui Ge, Jiayuan Gu, Chenke Wang, Yu Long · 6 authors

Payment channel hubs (PCHs) serve as a promising solution to achieving quick off-chain payments between pairs of users. They work by using an untrusted tumbler to relay the payments between the payer and payee and enjoy the advantages of low cost and high scalability. However, the most recent privacy-preserving payment channel hub solution that supports variable payment amounts suffers from limited unlinkability, e.g., being vulnerable to the abort attack. Moreover, this solution utilizes zero-knowledge proofs, which bring huge costs on both computation time and communication overhead. Therefore, how to design PCHs that support variable amount payments and unlinkability, but reduce the use of huge-cost cryptographic tools as much as possible, is significant for the large-scale practical applications of off-chain payments.

Rakshitha Channarayapatna Mullegowda, Nirmala Hiremani, Mahantesh N. Birje, Nataraj Kanathur Ramaswamy

Several countries have been researching digital voting methods in order to overcome the challenges of paper balloting and physical voting. The recent coronavirus disease 2019 (COVID-19) epidemic has compelled the remote implementation of existing systems and procedures. Online voting will ultimately become the norm just like unified payments interface (UPI) payments and online banking. With digital voting or electronic voting (e-voting) a small bug can cause massive vote rigging. E-voting must be honest, exact, safe, and simple. E-voting is vulnerable to malware, which can disrupt servers. Blockchain’s end-to-end validation solves these problems. Three smart contracts-voter, candidate, and voting-are employed. The problem of fraudulent actions is addressed using vote coins. Vote coins indicate voter status. Sidechain technology complements blockchain. Sidechains improve blockchain functionality by performing operations outside of blockchains and delivering the results to the mainchain. Thus, storing the encrypted vote on the sidechain and using the decrypted result on the mainchain reduces cost. Building access control policies to grant only authorized users’ access to the votes for counting is made simpler by this authorization paradigm. Results of the approach depict the proposed e-voting system improves system security against replay attacks and reduces the processing cost as well as processing time.

Zheyi Zhang, Yinghong Cao, Hadi Jahanshahi, Jun Mou

With the rapid development of blockchain technology, the security of non-fungible tokens (NFT) in the transaction process has attracted much attention. In the transaction process, the commoditized NFT images will inevitably involve display and leakage problems, which is likely to lead to economic losses drink copyright disputes between the trading parties. To protect transaction security, a chaotic color multi-image compression encryption/LSB data-type steganography scheme is proposed in the paper. A series of chaotic sequences are obtained by iterating the chaotic map, while compression sensing (CS) is introduced to compress multiple secret images and fuse the compressed secret images into one large secret image. Then this image is encrypted, and the encrypted large secret image is hidden on multiple cover images by steganography. This encryption can hide the change in the statistical properties caused by steganography. Finally, the cover image is combined with the 3D object model by using it as a texture for the 3D object model to realize the type steganography of the image data. The simulation and performance test results of the scheme illustrate that the scheme has a large enough key space and steganography capacity, as well as good resistance to differential attacks, statistical attacks, compression reconstruction quality, and robustness. This scheme can well protect the transaction security of NFT images, and at the same time open a channel connecting 2D images and 3D obj textured models, which provides a new idea for steganography.

Dawei Xu, Jiaqi Gao, Liehuang Zhu, Feng Gao · 5 authors

Bitcoin is a decentralized digital cryptocurrency. Its network is a Peer-to-peer(P2P) network consisting of distributed nodes. Some of these nodes are always online and in this article are called Bitcoin backbone nodes. They have a significant impact on the stability and security of the Bitcoin network, so it is meaningful to analyze and discuss them. In this paper, we first continuously collect information about Bitcoin nodes from July 2021 through June 2022 (which is the longest duration of data collection to date). In total, we collect information on 127,613 Bitcoin nodes. At the same time, we conclude that the fluctuation of Bitcoin nodes is directly related to the fluctuation of onion network nodes. Further, we filtered 2694 Bitcoin backbone nodes based on our algorithm. By analyzing the backbone nodes' attributes such as geographic distribution, client version, operator, node function, and abnormal port number, it is demonstrated that these nodes are centralized and play an important role in the Bitcoin network. Based on this, three unsupervised machine learning algorithms are selected to cluster multiple attributes of backbone nodes in a more scientific way. In this paper, the whole process from data collection to cluster analysis is completed and the best results are obtained by comparison. The experiments proved the existence of centralization of Bitcoin backbone nodes and obtained the number of nodes within each cluster. Finally, cluster nodes are de-anonymized based on the optimal results. Through our experiments, we obtain organizational information about the deployers of 103 nodes, linking the Bitcoin backbone nodes to the real world, thus accurately demonstrating the existence of Bitcoin centrality.

Sumit Shevtekar -, Radhey Saykar -

Blockchain based E-voting system can be revolution- ary in terms of security and tamper proof, transparent elections and hence empower the democracy. Blockchain E-voting is already implemented at organisational level. But at state/national level it faces challenges such as privacy, stability, latency etc. To counter them we require advanced implementation techniques from multiple disciplines. These techniques are 2-layer-solution, sharding for scalability issue, optimizing consensus algorithm and off-chain transaction for reducing latency, zero knowledge proof, using multiple protocols for user privacy etc. General architecture of blockchain is explained in details which combines election creation, voter registration, voter transaction, tallying the results and vote verification. We have discussed how integrating E-voting with blockchain document verification system can be benificial. It is complicated to implement at state, national level and need additional research and implementation to make blockchain E- voting acceptable in elections across the world. Through research and innovation we can make blockchain voting mainstream.

Dingjie Xu, Na Ren, Changqing Zhu

Existing zero-watermarking algorithms for remote sensing images heavily rely on traditional feature extraction techniques, which are vulnerable to targeted attacks and lack discriminability for images captured by different sensors or at different time periods in the same geographical area. To address these limitations, this paper proposes a novel watermarking algorithm based on blockchain and Stacked Denoising Autoencoder (SDAE) to achieve lossless copyright protection for high-resolution remote sensing images (HRRS). The algorithm utilizes SDAE to extract deep and robust features from local square feature regions (LSFR) for watermark construction. Moreover, the algorithm incorporates a watermark registration scheme designed with Hyperledger Fabric and IPFS to ensure secure and trustworthy registration of watermarks and associated parameter information, enhancing the algorithm's uniqueness. Experimental results demonstrate the effectiveness of the proposed algorithm against various watermark attacks and its high discriminability for similar images. This algorithm holds significant potential for wide-ranging applications in the field of lossless copyright protection for HRRS, effectively safeguarding the commercial interests of data providers.

Garima Mathur

<title>Abstract</title> Blockchain technology has gained significant attention in recent years due to its decentralized and secure nature. Ethereum a popular blockchain platform supports the execution of smart contracts and enables the storage of data on the blockchain. However Ethereum's public nature may not be suitable for scenarios where sensitive or private data needs to be stored and accessed securely. In this paper we present GANACHE an efficient private Ethereum blockchain tool that addresses the confidentiality and security concerns associated with data storage. GANACHE leverages various cryptographic techniques such as encryption and zero-knowledge proofs to ensure the privacy of stored data while maintaining the benefits of blockchain technology.

Vinayak Musale, Pranav Mandke, Debajyoti Mukhopadhyay, Swapnoneel Roy · 5 authors

No abstract is available for this record.

Geunyoung Kim, Jae‐Cheol Ryou

Anonymity forms the basis of decentralized ecosystems, leading to an increase in criminal activities such as money laundering and illegal currency trading. Especially in blockchain-based metaverse services, activities such as preventing sexual crimes and verifying the identity of adults are becoming essential. Therefore, avatar authentication and the KYC (Know Your Customer) process have become crucial elements. This paper proposes a mechanism to achieve the KYC process by verifying user identity using smart contracts. Users obtain an SBT (Soul Bound Token) from the metaverse service provider through the DID (Decentralized Identity) credential issued during the KYC process. The identity verification of avatars occurs within smart contracts, ensuring user privacy and protection through ZKP (Zero Knowledge Proof). Tools for generating ZKP are also provided, enabling users, even those who are unfamiliar with ZKP, to use them conveniently. Additionally, an integrated wallet is offered to seamlessly manage DID credentials and SBTs. Furthermore, in case of avatar identity issues, users can request an audit by the issuer through the associated DID tokens.

Najmath Ottakath, Abdulla Al‐Ali, Somaya Al-Máadeed, Omar Elharrouss · 5 authors

Videos and image processing have significantly transformed computer vision, enabling computers to analyze, and manipulate visual data. The proliferation of cameras and IR equipment has facilitated the collection of valuable information about individuals and their surroundings. These technologies find applications in various domains, ranging from biometric entry cards and high-security clearances to surveillance. These applications form part of the Internet of Things (IoT), forming a centralized network. However, the proliferation of data and its sharing brings challenges related to security, privacy, and storage. Interactions with third-party systems may introduce vulnerabilities. To address these issues, researchers in computer vision have explored the integration of blockchain technology into various applications. This paper presents a comprehensive survey of blockchain applications in computer vision, focusing on image and video data sharing, video surveillance, biometrics, and video integrity protection. The aim is to explore how the blockchain can enhance the security, privacy, and authentication of them. It also discusses tools and techniques employed at the edge to achieve these objectives while highlighting opportunities for further improvements. Overall, this review provides insights into the integration of blockchain and computer vision, advancements, challenges, and future directions in leveraging image and video data in a blockchain-enabled environment.

Awatef Salem Balobaid, Yasamin Alagrash, Ali Fadel, Jamal N. Hasoon

Blockchain technology can be employed in the education sector by building a decentralized system to store and share student records. The records can be encrypted to guarantee their confidentiality and security. With a blockchain-based system, student records can be saved in blocks that are linked and secured via cryptography. The records are decentralized and not controlled by any single entity, making them less susceptible to hacking or tampering. By using blockchain technology, educational institutions can create a more secure and efficient system for storing and sharing student records. This can streamline the process of transferring records between schools, and provide a secure and transparent way for students to access their own records. In this study, we provide a novel Merkle tree-based strategy for preserving the accuracy of student records and outline how to put it into practice. The software architecture resembled blockchain technology and was developed for private network deployment. The key components of our strategy are replacing conventional audit trails with their cryptographically secure equivalent and simplifying the Blockchain framework by avoiding mining. The cryptography system's framework is presented, and the new five dimensions of chaotic map academic records are proposed. Our study utilizes deoxyribonucleic acid (DNA) sequences and operations and the chaotic system to strengthen the cryptosystem in the blockchain authentication and authorization process. The significant advantage of this method is enhancing the generation of the hash function, which is the most critical challenge in the blockchain concept. The experimental outcomes and security analysis demonstrated that the proposed method works well in terms of different aspects. The suggested hash function's hash value distribution, sensitivity to tiny message modifications, confusion and diffusion qualities, resilience against birthday attacks, keyspace analysis, collision resistance, efficiency, and flexibility were all considered throughout the study.

Ruta Jawale, Dakshita Khurana

A non-interactive ZK (NIZK) proof enables verification of NP statements without revealing secrets about them. However, an adversary that obtains a NIZK proof may be able to clone this proof and distribute arbitrarily many copies of it to various entities: this is inevitable for any proof that takes the form of a classical string. In this paper, we ask whether it is possible to rely on quantum information in order to build NIZK proof systems that are impossible to clone. We define and construct unclonable non-interactive zero-knowledge arguments (of knowledge) for NP, addressing a question first posed by Aaronson (CCC 2009). Besides satisfying the zero-knowledge and argument of knowledge properties, these proofs additionally satisfy unclonability. Very roughly, this ensures that no adversary can split an honestly generated proof of membership of an instance $x$ in an NP language $\mathcal{L}$ and distribute copies to multiple entities that all obtain accepting proofs of membership of $x$ in $\mathcal{L}$. Our result has applications to unclonable signatures of knowledge, which we define and construct in this work; these non-interactively prevent replay attacks.

Akihiro Fujihara

In Bitcoin Core (BTC), there exists an upper limit of the block size around 1MB, which causes the Bitcoin scalability problem that severely limits transaction processing capacity.On the other hand, Bitcoin SV (BSV) forked from BTC is known to eliminate this limit.In BSV, the size of mined blocks is generally not uniform, but a mixture of various different sizes.Block miners in BSV can get more transaction fees as a reward, while there is a risk that the success rate of block mining decreases because it has to take a longer time to verify all the transactions in the block.For this reason, the selection of block size depends on mining strategy of each miner.To the best of our knowledge, there has been no detailed report on how each miner selects a block size.In this paper, we firstly formulated the Bitcoin scalability problem using a mathematical model of transaction processing capacity.Then, we investigated the probability distributions of block size in both Scaling Test Network (STN) and Mainnet of BSV.As a result, we found that the aggregate block size distribution in STN follows an exponential distribution, while that in the Mainnet follows a power-law distribution whose exponent is around one.We demonstrated a theoretical explanation of the difference between two distributions in the STN and Mainnet with a unified manner based on an underlying incentive mechanism.

Lucas Mayr, Lucas Palma, Gustavo Zambonin, Wellington Fernandes Silvano · 5 authors

Private key management is a complex obstacle arising from the traditional public key infrastructure model. However, before any related security breach can be addressed, it must first be reliably detected. Certificate Transparency (CT) is an example of a certificate issuance monitoring strategy, developed to detect the possible malfeasance of certification authorities (CAs). To the best of our knowledge, CT and other detection mechanisms do not cover digitally signed documents made by an end user, which are also susceptible to CA misbehavior. We modify the CT framework to handle signed documents via logging certificates in the blockchain to enable the secure and user-friendly monitoring of one-time signatures, backdating protection, and effective CA misbehavior detection. Moreover, to demonstrate the feasibility of our proposal, we present distinct deployment scenarios and analyze the storage, performance, and monetary costs.

Lin Wang, Changgen Peng, Weijie Tan

Blockchain integrates peer-to-peer networks, distributed consensus, smart contracts, cryptography, etc. It has the unique advantages of weak centralization, anti-tampering, traceability, openness, transparency, etc., and is widely used in various fields, e.g., finance and healthcare. However, due to its open and transparent nature, attackers can analyze the ledger information through clustering techniques to correlate the identities between anonymous and real users in the blockchain system, posing a serious risk of privacy leakage. The ring signature is one of the digital signatures that achieves the unconditional anonymity of the signer. Therefore, by leveraging Distributed Key Generation (DKG) and Elliptic Curve Cryptography (ECC), a blockchain-enabled secure ring signature scheme is proposed. Under the same security parameters, the signature constructed on ECC has higher security in comparison to the schemes using bilinear pairing. In addition, the system master key is generated by using the distributed key agreement, which avoids the traditional method of relying on a trusted third authorizer (TA) to distribute the key and prevents the key leakage when the TA is not authentic or suffers from malicious attacks. Moreover, the performance analysis showed the feasibility of the proposed scheme while the security was ensured.

Saeed Banaeian Far, Seyed Mojtaba Hosseini Bamakan

Abstract A considerable number of people worldwide start their second lives in the digital world soon. The 3D Internet reflects the digital world. Metaverse, the most famous example of the 3D Internet, is very popular and practical in people’s daily lives. However, combining Metaverse with newly-emerging technologies (e.g., blockchain) provides new user-friendly features such as autonomy, accessibility, removing central authorities, etc. Despite the mentioned attractive features, blockchain-based metaverses suffer various challenges, such as one user with multiple identities, certificate issuing for users in Metaverse, authentication-related issues, and arresting malicious users. Generally, identity management in a distributed environment where no central authority exists is a challenging issue. This study focuses on the challenge of distributed identity management in Metaverses to strike a balance between users’ privacy and regulation. The study proposes the use of Non-Fungible Tokens (NFTs) as a tool for managing identities in metaverses, as they are considered an excellent choice for this purpose. In addition to explaining the importance of this idea, this paper identifies its challenges, including distributed identity management, authentication issues, and security and privacy aspects. It then proposes possible solutions (e.g., using cryptographic tools). Despite existing challenges, there are many opportunities in the popularization of Metaverse, such as relying on blockchain technology, emerging many Metaverse-related jobs, in-Metaverse investments for huge revenues, and applying digital twins to provide realistic senses. This study also highlights the critical role of artificial intelligence (AI) in metaverses.