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Blockchain for the Metaverse: A Review
Thien Huynh-Thea, Thippa Reddy Gadekallub,c, Weizheng Wangd, Gokul Yendurib, Pasika Ranaweerae,
Quoc-Viet Phamf, Daniel Benevides da Costag, Madhusanka Liyanageh
aDepartment of Computer and Communication Engineering, Ho Chi Minh City University of Technology and Education, Vietnam
bSchool of Information Technology, Vellore Institute of Technology, India
cDepartment of Electrical and Computer Engineering, Lebanese American University, Byblos, Lebanon
dDepartment of Computer Science, City University of Hong Kong, Hong Kong SAR, China
eSchool of Computer Science, University College Dublin, Ireland
fSchool of Computer Science and Statistics, Trinity College Dublin, Ireland
gTechnology Innovation Institute, 9639 Masdar City, Abu Dhabi, United Arab Emirates
hSchool of Computer Science, University College Dublin, Ireland
Abstract
Since Facebook officially changed its name to Meta in Oct. 2021, the metaverse has become a new norm of social networks
and three-dimensional (3D) virtual worlds. The metaverse aims to bring 3D immersive and personalized experiences to users by
leveraging many pertinent technologies. Despite great attention and benefits, a natural question in the metaverse is how to secure its
users’ digital content and data. In this regard, blockchain is a promising solution owing to its distinct features of decentralization,
immutability, and transparency. To better understand the role of blockchain in the metaverse, we aim to provide an extensive survey
on the applications of blockchain for the metaverse. We first present a preliminary to blockchain and the metaverse and highlight
the motivations behind the use of blockchain for the metaverse. Next, we extensively discuss blockchain-based methods for the
metaverse from technical perspectives, such as data acquisition, data storage, data sharing, data interoperability, and data privacy
preservation. For each perspective, we first discuss the technical challenges of the metaverse and then highlight how blockchain
can help. Moreover, we investigate the impact of blockchain on key-enabling technologies in the metaverse, including Internet-of-
Things, digital twins, multi-sensory and immersive applications, artificial intelligence, and big data. We also present some major
projects to showcase the role of blockchain in metaverse applications and services. Finally, we present some promising directions
to drive further research innovations and developments towards the use of blockchain in the metaverse in the future.
Keywords: Blockchain, Metaverse, Smart COntracts, Privacy, Vertical Applications.
1. Introduction
The metaverse is the next phase of digital evolution that can
revolutionize the digital adoption to a staggering level and ex-
tends the domain of services beyond the standard systems with
online access. Digitization of services has become the trend for5
improving the efficiency in the fields of business, entertainment,
education, or any other system that can be integrated with on-
line access over the past few decades. These services and sys-
tems were improved to its maximum potential with the capa-
bilities provided with digital systems and online storage/pro-10
cessing facilities at remote data centres and cloud platforms.
With the efficiency, performance, and quality of the service ac-
cess reaching to its highest potential, the perspective has been
shifted towards the consumer experience. Thus, the demand for
Email addresses: thienht@hcmute.edu.vn (Thien Huynh-The),
thippareddy.g@vit.ac.in (Thippa Reddy Gadekallu),
weizheng.wang@ieee.org (Weizheng Wang),
gokul.yenduri@vit.ac.in (Gokul Yenduri),
pasika.ranaweera@ucdconnect.ie (Pasika Ranaweera),
viet.pham@tcd.ie (
Quoc-Viet Pham), danielbcosta@ieee.org (Daniel Benevides da Costa),
madhusanka@ucd.ie (Madhusanka Liyanage)
improved service experience with more interactive capability15
is ever increasing and service providers are keen on elevating
their existing standards to the next level. In fact, consumers are
demanding haptic and immersive capabilities with their digital
interfacing, where such traits are only possible with the emerg-
ing technologies of Virtual Reality (VR), Augmented Reality20
(AR), Mixed Reality (MR), and Extended Reality (XR) [1].
The metaverse is the solution that amalgamate all these perti-
nent technologies in the global context. This concept creates a
simulated digitized environment that can be endured as an im-
mersive virtual world for its prosumers. Users can interact with25
this virtual eco system through their digital avatars in compli-
ance to the duality principle [2]. Concretely, the avatars are the
virtual embodiments of the users, and has the same legal author-
ity in the metaverse as one’s legal rights in the real world; this
makes the avatar warranted for any transactions made within30
the virtual domain and restricts from repudiating any commit-
ted action. The access can be gained by any person having a
VR/AR enabled immersive device, such as a headset or a glass
under the minimal capability [3]. On the contrary, full-body
haptic bodysuits such as Teslasuit or Holosuit carries the poten-35
tial to embrace the immersive experience to its peak with the
Preprint submitted to Elsevier February 12, 2023
capability to track the motions, extract haptic feedback along
with transcended biometrics.
Despite the metaverse being developed and intended to ex-
pand the scope of capabilities in social media, its potential for40
other industrial, commercial, societal, educational, medical, mil-
itary, and governmental sectors are immense. Lack of immer-
sive experience is a well-known drawback with the online re-
mote access and control systems. Specially in the instances of
controlling Supervisory Control and Data Acquisition (SCADA)45
or Programmable Logic Controller (PLC) based remote automa-
tion systems [4], fitting on apparels, perception in commercial
real-estate or architecture, understanding Three-Dimensional (3D)
visualization in medical/engineering/or architectural educa-
tion, remote controlling of unmanned aerial/naval/or ground50
vessels, experiencing digital entertainment beyond the 2 dimen-
sions are areas that required more innovation. Though AR and
VR technologies offered standalone solutions for these areas,
an all-in-one platform or an environment was lacking to com-
bine these tools. The metaverse offers this digital eco-system55
to the world, and widely open the scope of possibilities beyond
measure. The concept of Digital Twins (DTs) empowers the re-
mote operation and controlling of machines or vehicles with im-
proved visualization and coordination, and benefit both indus-
trial and military sectors [5]. Three-dimensional visualization60
is leading for better accuracy and understanding of the context
that benefit both educational and entertainment applications. In
addition, novel directives such as AR based remote robotic con-
trolling, AR based remote surgery are achievable with the meta-
verse platform [6]. Further, the concept such as cryptocurrency65
[7], digital-biometrics [8], and explainable artificial intelligence
(XAI) [9] are facing unavoidable challenges when implement-
ing them in the real-world; with the issues of integrating to ex-
isting systems, compatibility, inter-operability, legal, and ethi-
cal discrepancies. As the metaverse is a newly building world,70
implementing these strategies at the design stages would allow
more assurance on security and privacy for its users with en-
hanced service experience.
Though the metaverse is produced as a panacea for future
digital expansion, there exist challenges and pragmatic issues75
hovering around it. Most critical issue being the lack of a ser-
viceable digital infrastructure to offer the guaranteed services
and applications with attributed processing and networking ca-
pabilities. Even such an infrastructure exists, access technolo-
gies required to offer the envisaged specifications are only vi-80
able with emerging 5G mobile technology, which is still in its
experimental stages and not deployed globally. The compat-
ibility and inter-operability between the virtual and physical
worlds are to be understood and standardized before launching
the metaverse. It is obvious that, even with a formidable level85
of a processing capability at the metaverse engines, resources
might not be sufficient to serve the demand considering its po-
tential and scalability with the social-media backbone. Thus,
optimum processing and operation strategies must be adopted
to alleviate the cost in terms of processing, storage, networking,90
and financial. Such strategies are only possible through auto-
mated AI based approaches and requires more assimilation and
research on that subject. As a person is required to be equipped
with a headset or a AR glass to access the metaverse at the
minimum, the higher personal investment makes it a privileged95
service rather than a open system for everyone. Further, se-
curity and privacy of the users are imperative aspects, where
certain privacy laws possible in the real-world might not be ac-
countable in the virtual domain, while the prominent biometrics
in the real-world can be replicated within the digital domain.100
Therefore, deploying the metaverse in a pragmatic context re-
quires much more research and proper standardization.
XR is an obvious technology required for the metaverse de-
velopment, where current AR and MR technologies should be
improved to the level in which to advocate full integration of105
virtual entities to a super-realistic level, and to improve its om-
nipresence. AI, as specified earlier, plays a key role in automat-
ing the metaverse eco-system to hand in the complete control
to the digital governance. AI involvement will further assure
the prosumers of their digital assets and content safety, that is110
bounded by their avatar. Existing computer vision processing
should be empowered with AI integration to enhance the 3D
image processing, while image/video/3D rendering technolo-
gies can be improved to accelerate the query processing of the
visual and telemetry data. XAI practices should be employed115
at the design stages to ensure global compliance for compati-
bility. As the existing cloud computing based storage and pro-
cessing infrastructure lacks the required networking capability
to host the metaverse applications, edge computing is a nascent
paradigm essential to launch it that enables elevated access ca-120
pacity along with context and location aware features due to
its proximate nature. Further, network slicing can be employed
to organize and structure the metaverse application flow among
the eight enablers presented in [2].
Introduced with the bitcoin cryptocurrency, blockchain rose125
to fame due to its unique ability to form a shared economy and
laid the foundation to existing digital currency market. Blockchain
has been considered a breakthrough technique for security and
privacy preservation [10]. In simpler terms, blockchain is a
ledger that stores the committed transactions to facilitate dig-130
ital asset tracing and securing in a commercial network. These
transactions or records being stored as blocks, are linked to-
gether using cryptographic measures, or hashing mechanisms
to be precise, ensures the ledgers‘ immutability and enables se-
cure sharing capability even in an insecure environment. Most135
salient feature of blockchain is its capability to operate on de-
centralized ledger content without a centralized authority [11].
Since blockchain is employing proof of work as the consensus
mechanism, the method itself deems it more secure and suit-
able for e-commerce platforms. In the context of the metaverse,140
blockchain is the pertinent enabler intended to enforce account-
ability into the digital eco-system.
The requirement for blockchain is imminent, where secur-
ing the digital content in possession of all the users of the meta-
verse is its prime purpose. The metaverse eco-system relies on145
blockchain for accounting their content and transactions to en-
sure user integrity, privacy, and reputation.
2
1.1. Related Works and Contributions
The metaverse related studies and surveys are widely avail-
able and has incremented over the past few years [12]. In spite150
of its evident potential, blockchain based studies are limited
and its wide adoption for various applications are not available
at present. The authors in [2] presented a comprehensive sur-
vey, and can be considered as the first scientific publication that
discussed about the metaverse on a broader technical context.155
Blockchain has been introduced as one of the technological en-
ablers out of seven other pillars. The authors identified data
storage, data sharing, and data interoperability as the main uses
of blockchain. A deeper study was not conducted on blockchain
as the scope of the paper is quite wide. The important position160
blockchain holds in the metaverse inception is discussed in [12]
concerning governmental and economic sectors while its possi-
ble utilization for virtual reality object connection is specified.
However, this survey fails to build on those specified facts de-
scriptively.165
The idea of fusing blockchain and AI for the metaverse
development was presented in [11] as a survey. This paper
discusses the potential correlation between the metaverse and
blockchain through the layered architecture composed of data,
network, consensus, incentive, contract, and application lay-170
ers. Though the authors present four blockchain empowered
applications, they are mostly focused on the commercial us-
age of blockchain. Contribution of blockchain and AI for the
metaverse was presented in [13], where handling and reusing
high quality/rich data, stabilizing the decentralized network,175
privacy of data, and handling of economic related data are dis-
cussed briefly. In addition, there are various studies [14, 15, 16]
that mention blockchain as a requisite for the metaverse, though
fails to discuss them rigorously. Table 1 emphasizes the contri-
bution of this paper. To the best of our knowledge, there hasn’t180
been a study that discusses the utilization of blockchain for the
metaverse applications. Thus, our study presents diverse poten-
tial applications for the metaverse where blockchain integration
would enhance their efficiency, and impact of blockchain for
enabling technologies.185
The main contributions of this survey are:
•Firstly, we present a brief overview of blockchain and the
metaverse, followed by the motivation behind integration
of blockchain in the metaverse.
•Secondly, we discuss application of blockchain for ad-190
dressing the challenges faced by several technical aspects
of the metaverse including, data acquisition, data stor-
age, data sharing, data interoperability, and data privacy
preservation.
•Thirdly, we discuss about the impact of blockchain on195
some of the key enabling technologies in the metaverse
such as Internet of Things, digital twins, multi-sensory
XR and hologrtaphic telepresence, AI, and the big data.
•Fourthly, we discuss about some of the interesting projects
such as Decentraland, Sandbox, Axie Infinity, and Illu-200
vium that leverage blockchain in the metaverse.
Table 1: Emphasizing the contribution of this paper in contrast to the state-of-
the-art
Context
[12]
[2]
[11]
[13]
[14]
[16]
Ours
Metaverse Technical
Perspective
✓ ✓ ✓ ✓ ✓ ✓ ✓
Blockchain as an En-
abling Technology for
Metaverse
✓ ✓ ✓ ✓ ✓ ✓ ✓
Applications of
Blockchain
✓ ✓ ✓ ✓ ✓
Technical Perspective of
Adoptable Blockchain
Methods
✓ ✓ ✓ ✓
Impact of Blockchain for
Metaverse Enablers
✓
✓Technical Analysis ✓High Level ✓Introducing
•Finally, we conclude the paper with some potential future
research directions.
1.2. Systematic Literature Survey
The following phases constitute the literature review that205
was used in this study to investigate the blockchain for the
metaverse: A Review. First, we investigated relevant scien-
tific and research publications on the role of blockchain in the
metaverse. We place a strong emphasis on peer-reviewed jour-
nals and high-quality articles published in reputed national and210
international conferences, seminars, books, symposiums, and
journals. The references used in this study were found in well-
known archives like Google Scholar and arXiv. We also re-
ferred to the publications in well-known publishers of IEEE,
Springer, Elsevier, Taylor & Francis, Wiley, and MDPI. Fur-215
thermore, the keywords of blockchain, the metaverse, privacy,
and vertical applications are used to identify relevant blockchain
references and publications for the metaverse. In the following
phase, all of the retrieved articles are screened based on their ti-
tles. We excluded any papers with poor-quality material. After220
that, we reviewed the abstracts of the papers to determine their
contributions. The data needed for our analysis of the role of
blockchain in the metaverse is extracted in the final step.
1.3. Paper Organization
The rest of this paper is organized as follows. The funda-225
mentals of blockchain,the metaverse, and the role of blockchain
in the metaverse are presented in Section 2. The applications of
blockchain for the metaverse from technical perspectives are
discussed in Section 3. In Section 4, we discuss the impact
of blockchain for enabling technologies in the metaverse, in-230
cluding IoT, digital twin, multi-sensory XR applications and
holographic telepresence, AI, and big data. After that, we dis-
cuss about some of the exciting projects related to blockchain
3
enabled metavserse applications in Section 5. Finally, we con-
clude the paper with some potential research directions in Sec-235
tion 6.
2. Blockchain and The Metaverse: Preliminaries
The preliminary introduction to blockchain and the meta-
verse is presented in this section, followed by the role of blockchain
in the metaverse.240
2.1. Preliminaries of Blockchain
The ability to mine a block is determined
by the computational power of each miner
A reward is given to the miner
who solves each block
Proof of Work
Proof of Stack
The ability to mine a block is determined by the
number of tokens of blockchain the user owns
The minter is provided with the
network fee or the gas fee
Figure 1: Popular Consensus Mechanisms.
The conception of blockchain origins from a white paper
written by Nakamoto Satoshi in 2008 [17]. Blockchain, also
called distributed ledger, owns consecutive blocks, which are
linked with each other through the hash value of previous block245
header. Other than the inevitable cryptographic hash, times-
tamp, nonce and transaction data are also included in a block
[18]. The block timestamp is considered valid only if its value is
more than the network-adjusted time plus two hours and greater
than the median timestamp of prior eleven blocks, which pre-250
vents adversary to manipulate the blockchain possibly. Note
that network-adjusted time refers to median of the timestamps
from entire connected nodes. The smooth execution of blockchain
is not just maintained by one or several nodes, instead, each
node in the blockchain network should comply with a common255
consensus protocol to generate and validate new blocks. Con-
sensus protocol is the backbone of blockchain where the op-
erating principles and legitimate actions are all regulated [19].
The famous bitcoin adopts Proof of Work (PoW) mechanism,
which demands miners to contribute a great number of comput-260
ing power to figure out an answer for the random mathematical
problem [20]. In order to avoid centralization of computing
power, the difficulty, also called nonce of next block genera-
tion, is dynamically changed on the basis of 10 minutes per
block. Although unimaginable computation power hinder ma-265
jority of attackers, PoW also leads to inefficient transaction rate
and excessive energy consumption. Proof-of-Stake (PoS) al-
leviates the problems brought by PoW, so the miner who be-
comes ultimate winner depends on their quantity of holdings in
the corresponding cryptocurrency rather than computing power270
[21]. The recent emerging InterPlanetary File System (IPFS)
propagates Proof of Space (PoSpace) consensus, which requires
participants to supply some storage space to prove a challenge
posted by the service provider [22]. The transaction data is or-
ganized in the form of Merkle tree for each block, which im-275
proves the verification efficiency. Note that Merkle tree enables
users to download any branch for check without full transaction
records. The above-mentioned general parts of blockchain and
the processing of transactions in a blockchain are depicted in
Fig. 2 and Fig. 3 respectively.280
The representative of first generation blockchain is bitcoin,
which only decentralizes the transaction records. Later, re-
searchers found the blockchain can overload more functions
such as asset management and family trust not merely a ledger.
Hence, the second generation of blockchain-Ethereum came285
into the picture. The main innovation brought by Ethereum is
the emergence of smart contracts [23]. The rules of smart con-
tract written into codes are stored in the blockchain. The trans-
actions can be used to trigger the corresponding functions in the
smart contracts, which automatically transfer funds or send no-290
tifications to the predetermined accounts. Since the smart con-
tract is accessible to everyone, a series of applications spring up
in a short time. For example, smart contracts strengthen the se-
curity of voting process, which becomes hard to be manipulated
and decoded by the malicious guys. Moreover, the insurance295
industry unites hospitals to track and record patient informa-
tion in the blockchain, where the smart contract can help the
corporations claim settlement to the patient immediately. Re-
cently, one of the smart contract derivation–Non-fungible to-
kens (NFTs) are popular around the world. Ethereum issues300
some standards such as ERC-721 and ERC-1155 to introduce
the features of assets built on NFTs. Unlike cyrptocurrencies in
Bitcoin and Ethereum, each NFTs are non-interchangeable and
cannot be divided. The NFT market is now worth more than $7
billion dollar, including art, games, sports, copyright, insurance305
and many other areas [24].
2.1.1. Popular Consensus Mechanisms
In blockchain, a consensus mechanism is a fault-tolerant
mechanism that is used to obtain the required agreement on a
single data value or a single network state across decentralized310
nodes. The popular consensus mechanisms are discussed in this
subsection and also depicted in Fig. 1.
1. Proof of Work: Most cryptocurrencies use PoW con-
sensus as their preferred consensus method. To validate
the transaction and add a new block to the blockchain,315
the algorithm is employed. Cynthia Dwork and Moni
Naor initially introduced the concept of PoW in 1993,
and Satoshi Nakamoto subsequently used it in the Bitcoin
paper in 2008. Markus Jakobsson and Ari Juels used the
term ”proof of work” in a publication in 1999. The PoW320
consensus mechanism is used to validate the transaction
and add a new block to the blockchain. In this method,
minors (a group of individuals) compete against one an-
other to finish the network transaction. Mining is the act
of competing with one another. Upon successfully cre-325
ating a legitimate block, miners are rewarded. Bitcoin
is the most well-known application of PoW. Producing
PoW can be a random, low-probability operation. Before
4
a valid proof of work can be developed, there must be sig-
nificant trial and error. Proof of work is based on a mathe-330
matical puzzle whose solution can be easily proved. The
Hashcash PoW method can be used to implement PoW
on a blockchain [25].
2. Proof of Stake: On July 11, 2011, the proof-of-stake
(PoS) concept was originally discussed on the forum ”Bit-335
coinTalk.” Sunny King and Scott Nadal initially proposed
PoS in a publication in 2012 with the goal of address-
ing the issue of PoW mining’s excessive energy usage.
Peercoin, which debuted in 2012, was the first proof-of-
stake cryptocurrency to be operational. Following were340
other cryptocurrencies like Cardano, Nxt, Blackcoin, and
Algorand. Ethereum, the second-largest cryptocurrency
in the world in 2022, transitioned from a proof-of-work
to a proof-of-stake consensus mechanism. The founding
principle of PoS revolves around the idea that nodes that345
wish to take part in the block building procedure must
initially demonstrate that they own a specific amount of
coins. Additionally, in order to take part in the block
generation process, they must deposit a set quantity of
their coins, known as stake, into an escrow account. The350
stake serves as a promise that it will follow the protocol’s
regulations. The node that escrows its share in this way
is referred as in PoS as the stakeholder, leader, forger,
or minter. If the minter misbehaves, it might forfeit the
stake. In essence, escrowing a share makes a stakeholder355
an implicit member of a restricted group. It is only possi-
ble to join this exclusive group and create blocks within.
If a shareholder is given the opportunity to build a new
block, they will be rewarded in one of two ways. Either
it is given a set amount of coins that serve as a kind of in-360
terest against their investment, or it is able to collect the
transaction fees within the block [26].
Block 1 Header
Hash Value of the
Previous Block
Header
Root of Hash Tree
TX1-1
TX1-2
TX1-3
Block 2 Header
Hash Value of the
Previous Block
Header
Root of Hash Tree
TX2-1
TX2-2
TX2-3
Block 3 Header
Hash Value of the
Previous Block
Header
Root of Hash Tree
TX3-1
TX3-2
TX3-3
Hash Value
H H
H
Hash Value Hash Value
H
Hash Value Hash Value
H
Hash Value Hash Value
TX2-1 TX2-nTX2-2 TX2-3
H
...
HHash function
Connection of BlocksCollection of Transactions
Transactions
Figure 2: General structure of a blockchain, in which blocks connected with
each other through their respective hash codes.
A transaction
is request
A block representing
the transaction is
created The block is transmitted to a peer-
to-peer networking computers
scratter across the world
The network validates and
confirms the transaction's
validity built in the block
The block is chained
together creatig a long
history of all transactions.
Nodes in the network
receive a reward for
the Proof of work
The transaction is
complete
Figure 3: Illustration of a transaction processed by the blockchain technology.
2.2. Preliminaries of the Metaverse
2.2.1. What is the metaverse?
The word “meta” origins from the Greek language, which is365
a prefix that means “more comprehensive” or “transcending”1.
The word “Verse” is abbreviated version of universe, which rep-
resents a space/time container 2. When these two words are
combined, a brand new word “Metaverse” comes into the pic-
ture, where the traditional social systems are transformed into370
a novel digital living space. State-of-the-art technologies such
as virtual reality (VR), digital twin, blockchain, etc are used to
build the metaverse that maps everything in our real world [15]
to a parallel universe. For example, users can work, live and
play with friends from any place in the metaverse. In 1992,375
Neal Stephenson, in his famous science fiction novel called
Snow Crash [27] firstly proposed the initial conception of the
metaverse, where people utilize digital avatars to control and
compete with each other to upgrade their status. However, till
now, the metaverse is in its conceptional stage; there are com-380
mon standards and very few real implementations are available.
2.2.2. What are enabling technologies of metaverse?
The metaverse is a fusion of multiple emerging technologies
such as 6G, artificial intelligence (AI), VR and digital twins.
The core technologies required in the metaverse are:385
1. The most important technology for realization of the meta-
verse is extended reality technology, including AR and
VR. While AR can overlay and superimpose digital infor-
mation onto the physical environment, VR allows users
to experience the digital world in a vivid way [28]. Both390
these techniques are very important in the development
of the metaverse, which creates digital space where the
users can interact as in the real world.
2. The second important technology is digital twin, which
establishes a virtual twin of a real world object by uti-395
lizing real world data to predict the expected behavior of
1https://en.wikipedia.org/wiki/Met
2https://alldimensions.fandom.com/wiki/Category:Verse
5
the real world object [29, 5, 30]. In the metaverse, digi-
tal twin can mirror the real world into the virtual world.
Correspondingly, the metaverse can also find some trial
solutions to the unsolved issues in the real world.400
3. The third technology–blockchain plays two irreplaceable
roles in the metaverse. On one side, blockchain technol-
ogy serves as a repository, so users can use it to store data
anywhere in the metaverse. On the other side, blockchain
technology can provide a complete economic system to405
connect the virtual world of the metaverse with the real
world. Especially, the above-mentioned NFTs allow vir-
tual goods to become physical objects. Users are allowed
to trade virtual items in the same way as in the real world.
Hence, blockchain bridges the real world and the meta-410
verse [13].
4. Future 6G wireless systems could provide higher levels
of computing, sensing, localization, and communication
resources that would enable faster transmission speeds
which are key essential for the metaverse. In the meta-415
verse, participants can get the immersive experiences in
gaming, education, entertainment, engineering and many
other fields without sensible latency [31].
2.2.3. What are applications of the metaverse?
Some of the popular applications of the metaverse are as420
follows.
•Online video conference: In the surreal atmosphere of
the Covid-19 pandemic, many small corporations are kept
alive through the application of telecommuting. How-
ever, as we all know, face-to-face communication is sig-425
nificant, 70% expression of people comes from body lan-
guage rather than verbal language. Telecommuting has
a number of problems unlike traditional face-to-face col-
laboration, such as inefficient cooperation, delay interac-
tion and misunderstood feedback [32]. However, in the430
metaverse, people can utilize a friendly avatar to walk
around and work in the virtual space. Even the body lan-
guage or eye interaction can be used to communicate with
working partner from different angles, which will greatly
improve telecommuting.435
•Digital Real Estate: In general, real estate refers to prop-
erty consisting of land and buildings, which can be used
for establishment, living, investment, rent, sale and buy.
In the metaverse, the above-mentioned activities can also
be implemented. Besides, the same factors in the reality440
such as location, amenities and transportation can influ-
ence house prices in the virtual world. For example, in
the metaverse, users can collect and sell households to
the public for a second time, as well as organize art exhi-
bitions, music festivals, gaming competitions and so on.445
The virtual platform explicitly emphasises the scarcity of
virtual land to users, which is offered to users at auction
and traded for NFTs [33].
•Digital Arts: Traditionally, people establish the 3D im-
ages through some modelling tools such as Maya and450
ZBrush. However, the metaverse has a strong focus on
the display layer, which brings new ways of expression
and artwork creation, so we can draw figures by using
a brush directly. On one side, with the growing popu-
larity of AI painting, digital art is gradually coming to455
the public’s attention. On the other hand, the emerging
blockchain technology has also brought traditional art-
works from offline to online. In the virtual gallery placed
in the metaverse, the users can enter the gallery to appre-
ciate from all dimensions [34].460
2.3. Role of Blockchain in the Metaverse
When it comes to the metaverse, the imagination of a vari-
ety of dazzling experiences or fun games may rise in our mind.
However, the scenario closely related to us is just a parallel
world, where the economic ecology is inevitable. Moreover, the465
digital assets are the core functions provided by the blockchain,
such as the homogenized tokens based on ERC-20 and the non-
homogenized tokens based on ERC-721 or ERC-1155. Since
the blockchain technology can maintain the smooth economic
operation of metaverse, blockchain technology is the soul of the470
metaverse. The adoption of blockchain infrastructure enables
the metaverse users to connect to the broader crypto-economy
by making virtual objects exchangeable for real-world currency.
Blockchain technology enables bitcoin and other cryptocurren-
cies to purchase and sell virtual assets in the metaverse. In the475
Metaverse, assets in the form of money or anything else can be
transferred and used across all virtual worlds. In the crypto-
enabled metaverse, users can go on a virtual vacation, buy dig-
ital clothes, and attend a virtual concert. Blockchain also en-
ables the metaverse to be a public platform with a decentralised480
open-source ecosystem that allows users to design applications
and conduct digital commerce. As an open-source blockchain
architecture, the metaverse will provide a user-friendly inter-
face for decentralised wallets and exchanges.
The motivation behind integration of blockchain in the meta-485
verse are summarized below
•Ensuring Data Privacy and Security: The metaverse
collects vast volumes of sensitive information in order to
present the user with the greatest possible experiences.
The organizations or the applications need this data for490
the successful development of targeting systems. If the
information is leaked into the hands of the wrong people
they might also target users in the real world. Blockchain,
with its authentication, access control, and the consensus
mechanisms provide the users complete control of their495
data thereby securing the data privacy of the users. The
blockchain uses asymmetric-key encryption and hash func-
tions which ensure security of data in the metaverse.
•Ensuring the Quality of the Data: The metaverse re-
ceives data from multiple applications ranging from health-500
care to entertainment. The AI models in the metaverse
6
rely on this data for making key decisions for its stake-
holders. The creation of the objects in the metaverse re-
lies highly on the quality of data shared by the users from
the real world. Blockchain, provides complete audit trails505
of transactions, allowing individuals and organizations to
validate all transactions [35, 36]. This will increase the
data quality in the metaverse.
•Enabling Seamless and Secured Data Sharing: The
metaverse depends on AR and VR devices, resulting in510
a more connected and immersive world. The metaverse’s
real benefit resides in its integration with AR on digi-
tal and physical objects. The metaverse’s success is de-
pendent on the seamless sharing of AR and VR data,
which enables the development of new, advanced appli-515
cations that aid in resolving real-world problems. The
blockchain’s advanced encoding information system en-
ables the metaverse’s data sharing to be seamless and se-
cure.
•Enabling Data Interoperability: In the metaverse, stake-520
holders need to access and hold assets in different virtual
worlds and use a variety of applications. Data interop-
erability across these virtual worlds is limited due to the
different environments in which they are built. It is pos-
sible to exchange data on two or more blockchains lo-525
cated in distinct virtual worlds using a cross-chain proto-
col. Users can migrate more easily between these virtual
worlds because of the blockchain’s interoperability.
•Ensuring Data Integrity: The metaverse’s data must be
maintained consistently and accurately. The stakehold-530
ers may lose faith in the metaverse if the integrity of the
data is compromised. The metaverse data is saved as a
copy in every block throughout the chain that can’t be
amended or removed without the consent of majority of
the participants, due to the immutability provided by the535
blockchain [37]. This mechanism of blockchain ensures
the data integrity of the metaverse.
Some use cases of application of blockchain in the meta-
verse are discussed below.
•Financial system: Tamper-proof, openness, transparency540
and decentralization are the four significant features in
blockchain. In the metaverse, millions of transactions
happen for goods exchange in a short time [38], so the
security and efficiency of these transactions must be guar-
anteed. Based on the above-mentioned features, blockchain545
based cryptocurrency is a good candidate for the large-
scale and scalable economic system construction in the
virtual world. In the metaverse, blockchain-based cryp-
tocurrencies allow peer-to-peer transactions. Rapid, sim-
ple, and relatively inexpensive e-commerce transactions550
are made possible by cryptocurrencies in the metaverse.
Since not all metaverses use the same coin, services of
crypto exchanges such as Coinbase and Binance are cru-
cial.
•Smart contract deployment: The inherent nature of the555
blockchain network allows smart contracts to be auto-
mated, programmable, open, transparent and verifiable
among other remarkable features, thus allowing for on-
chain trusted interactions without the need for a third-
party verification platform. If the financial system in the560
metaverse is built on top of the blockchain, the character-
istics of smart contracts can be used to decentralise the
operation of contracts in a programmed, non-custodial,
verifiable, traceable and trustworthy manner, thus sig-
nificantly reducing the harmful behaviours such as rent-565
seeking, corruption and underhanded operations that may
exist in the financial system, and can be widely used in
the financial, social and gaming sectors.
•NFTs: The most important feature of NFT is indivision
and uniqueness, which make it suitable for identity rep-570
resentation, for example, assets that are exclusive and
indivisible and can be freely traded and transferred. In
the metaverse, these virtual assets come with certificates
called NFTs that indicate ownership [24].
•Healthcare: Blockchain technology can be used to im-575
prove the efficiency and security of healthcare services in
metaverse. It can provide a secure, distributed ledger for
storing patient records and other sensitive data. Addition-
ally, blockchain-based smart contracts could enable auto-
mated payments between providers and insurers without580
the need for manual processing or third-party interme-
diaries. Decentralized identity protocols on blockchains
such as Ethereum could help ensure that only authorized
personnel have access to medical information while pro-
viding patients with greater control over their own health585
data [39].
3. Blockchain for the Metaverse: Technical Perspective
This section investigates the state-of-the-art blockchain-based
methods for the metaverse from the technical perspectives, in-
cluding data acquisition, data storage, data sharing, data in-590
teroperability, and data privacy preservation. The illustration
of blockchain for the above-mentioned technical aspects in the
metaverse is depicted in Fig. 4.
3.1. Data Acquisition
3.1.1. Introduction595
Data acquisition is an important step in the metaverse ecosys-
tem. Some of the sensitive data from the users such as bank/credit
card details are acquired when the users make payments. In
addition, sensitive data such as bio-metrics poses/gestures of
the users have to be acquired in the metaverse to create digi-600
tal avatars [40]. Data acquisition helps in training the AI/ML
algorithms that can assist in decision making, digital product
development, recommendation system development, and mar-
keting in the metaverse [15]. Data acquisition in the metaverse
will help applications create better insights, able to change over605
7
Security
Anonymity AuditsAuthentication Anti-tempering Access Control
Virtual Real
Estate
BLOCKCHAIN
Metaverse
Data Privacy
Data Inteoperability
Payments
NFT
Private key & public keyThird party applications
Traceability
Transparency Flexibility Adaptability
Data Sharing
Smart
Contract
Crosschain Technology
& Zero Trust
Mechanism
Diversified
Programming &
Smart Contract
Interplanetary File
System
High Transaction
Costs
Decentralized
LabelingLedger Availability Immutability
Data Storage
Decentralized
Storage
Latency & Hard
Forks
Immutability
Smart
Glasses
AR/VR
Devices
AI Bots
Haptic
Gloves
IoT
Devices
Smart
Devices
Data Acquisition
High quality and authentic data
Block chain
specific validation
Requires
huge
storage
Figure 4: Blockchain for technical aspects in the metaverse.
time, and adapt to new situations. The metaverse will be a digi-
tal marketplace where people can buy, sell, play, talk, and work
digitally using various devices as depicted in Fig. 4. Hence,
massive amounts of heterogeneous data will be generated [41].
Some of the data acquisition methods that can be used in the610
metaverse are as follows. Web forms will be one of the data
collection tools in the metaverse for gathering information from
users. Clients can quickly and easily fill out information using
web forms before being granted access to the metaverse capa-
bilities. Bots can capture personal information and required au-615
thentication elements like the social security number from the
users [42]. A high-definition camera in the metaverse helps to
gather information about a user’s physical attributes. The phys-
ical attributes of the user are used to build a digital representa-
tion of the user in the virtual world [33]. The client will benefit620
from the use of AR/VR gadgets to explore the metaverse. These
gadgets will be used to gather information about the user’s be-
havior [43].
3.1.2. Challenges of Data Acquisition in the Metaverse
Data generated through decentralized applications (Dapps)625
like WeiFund, Etheria, 4G Capital, and Ampliative Art in the
metaverse will be huge, unstructured, and real-time. It poses
a significant challenge in acquiring the enormous data being
generated. Data assurity or integrity will become important for
building applications like recommender systems in the meta-630
verse. These systems will be affected if the data is gathered
from unknown sources as it can impact the reliability of these
systems [44]. The volume of data will skyrocket in the meta-
verse as it provides high-quality digital services like Horizon
Worlds and Horizon Venues applications using VR headsets635
[45]. This will create a burden on data acquisition systems due
to increase in streaming in entertainment and other applications
[46]. Duplicate and inaccurate data may also be acquired which
will affect the quality of data [47].
3.1.3. How Blockchain Can Help640
The adoption of blockchain technology will make it eas-
ier for applications such as social networking to get authen-
tic data in the metaverse. The distributed ledger technology
of the blockchain will allow the acquisition of authentic data
and records as transactions. Every activity in a blockchain is645
recorded as a transaction, and each block includes a crypto-
graphic hash of the preceding block, a timestamp, and metadata
[48]. Therefore, data within a block cannot be modified with-
out compromising the other blocks. The data extracted from
any block is tamper-resistant [49]. Therefore, data acquired in650
the metaverse using blockchain is resistant to attacks, as the ma-
jority of nodes in the ledger must accept any modifications to
metaverse data [50]. All data acquired in the metaverse is sub-
jected to a blockchain-specific validation method that is pow-
ered by consensus mechanisms [51, 52]. This ensures that data655
is not duplicated in the metaverse. As the probability of pro-
ducing a duplicate block is nearly negligible in the blockchain-
enabled metaverse, the process of data acquisition is safer of
duplication. As each block in the blockchain is authorised,
8
the metaverse data obtained by blockchain-enabled acquisition660
mechanisms will be reliable [53].
3.1.4. Summary
In the metaverse, data acquisition presents a challenge in
terms of ensuring high-quality and authentic data. Although
blockchain technology will enable data acquisition systems to665
overcome these constraints, blockchain can be slow due to its
complexity and distributed nature [54]. A blockchain based
transaction can take much longer to complete. The entire trans-
action may take a few days. As a result, transaction fees are
higher than usual, and the number of users on the network is670
limited [55]. Data collected in a blockchain must be copied
along the chain, increasing storage demand. The more data
collected, the more storage space is needed [56]. To address
these issues in data acquisition systems, there is still room for
research in developing matured blockchain for the metaverse.675
3.2. Data Storage
3.2.1. Introduction
The metaverse is a digital realm that exists alongside the
physical world and is governed by humans. The metaverse will
comprise of experiences, places, and the things accessible over680
the Internet. The metaverse requires massive amounts of data
storage. Every person who enters the metaverse creates a data
file, and the data continues to grow as a result of social inter-
actions. Massive amounts of data will be generated once the
metaverse is built and implemented, laying a significant strain685
on the real world’s ability to process that information. Data
storage will have to be a top priority in order to put the meta-
verse to use [33].
3.2.2. Challenges of Data Storage in the Metaverse
In the metaverse, a digital reality exists alongside the physi-690
cal world. As more people join the digital worlds, large amounts
of data files are created, and as a result, the metaverse will gen-
erate voluminous data. The physical world’s data storage ca-
pacity will be pushed to the limits as soon as the metaverse is
fully operational. As a result, data storage will be a major chal-695
lenge for deploying metaverse applications like gaming, enter-
tainment, real estate, healthcare, etc [57]. There is a risk of data
leakage, tampering, or loss if the metaverse relies on a central
storage system. The high probability of data loss [58] and cor-
ruption in centralized applications endangers the metaverse’s700
ability to provide biometric data, vocal inflections, and vital
signs that rely on sensitive data [59]. Data labeling and organi-
zation will be another significant challenge with huge amounts
of data produced by the metaverse applications [60].
3.2.3. How blockchain can help705
For every transaction, a new block is created, making the
metaverse storage impenetrable to tampering [61]. Consequently,
data is saved as a replica of the original blocks throughout the
chain, boosting data reliability and transparency in the meta-
verse [13]. The metaverse applications, ranging from real es-710
tate to digital objects will be at high risk if the centralized data
storage is compromised [62]. The use of blockchain technology
will result in numerous blocks contributing to data distribution
and thereby increasing data availability in applications like vi-
tal monitoring and life support alerts in the metaverse. The de-715
centralized nature of blockchain technology allows data scien-
tists in the metaverse to collaborate and work on data cleansing,
which will significantly reduce the time and costs associated
with labeling data and preparing datasets for analytics [63].
3.2.4. Summary720
The decentralized nature of blockchain technology will re-
duce the time it takes to identify and label data while also serv-
ing as a collaborative platform for data scientists. Furthermore,
in the metaverse, the blockchain provides data reliability, trans-
parency, and availability as depicted in the Fig. 4. The data will725
be backed up in every block of the blockchain. A consensus-
based distributed ledger will help the data in the metaverse to
be resistant to tampering and duplication [64]. However, more
research is required to address the issue of latency, as any data
added must be mirrored throughout the entire chain. Although730
data tampering is impossible in blockchain, a hard fork is a pos-
sibility that must be considered.
3.3. Data Sharing
3.3.1. Introduction
Data sharing can benefit a diverse spectrum of the meta-735
verse stakeholders in numerous ways. As people and applica-
tions share the same platform, they may collaborate more ef-
fectively as depicted in Fig. 4. Everyone, from scientists to the
general public, will benefit from data exchange in the meta-
verse [65]. The data collected from AR/VR and IoT devices in740
the metaverse will be used to create personalized systems that
are customized to the users’ actions. This will enable a wide
variety of applications to deliver a more positive user experi-
ence [66]. Organizations will be able to conduct data analyt-
ics through the metaverse by disseminating information across745
applications. Shared data will help understand customers, eval-
uate advertising, personalize content, establish content strate-
gies, and build products in the metaverse [59].
3.3.2. Challenges of Data Sharing in metaverse
Sharing data in centralized data exchange platforms can ex-750
pose sensitive and private data of the data owners to heavy risk
in the metaverse [67, 68]. Data in the traditional sharing en-
vironment is highly mutable, this results in high latency and
lower data availability. Scaling the mutable data is challeng-
ing compared to the immutable data [69]. In the metaverse, nu-755
merous applications like healthcare, traffic optimization, media,
and entertainment will generate large volumes of data and will
be mostly real-time. Data flexibility becomes an issue when the
demand for real-time data increases in a traditional data-sharing
environment.760
3.3.3. How blockchain can help
Blockchain technology can make the transactions in crypto
exchange, education, and other applications more transparent
9
and precise in the metaverse [68]. Applications like governance
and finance will generate a decentralized, immutable record of765
all transactions, allowing stakeholders to view these records.
Hence, the stakeholders of the metaverse will benefit from greater
data transparency [70]. Blockchain will enable applications and
their users to understand how third-party applications like thun-
derbird, the bat, and pegasus manage data and can eliminate770
grey market transactions which will boost user confidence [71].
In addition, the data owner will have complete control over
the information. Data audits can also benefit from distributed
ledger technology. As a result, blockchain reduces the time and
money spent on validating the data [72]. Smart contracts will775
improve the flexibility in data sharing. They are typically used
to automate the execution of an agreement so that all partici-
pants can be certain of the outcome immediately, without the
involvement of an intermediary or the loss of time. Blockchain
allows smart contracts to be heterogeneous in programming.780
Hence, it will benefit applications like Nmusik, Ascribe, Tracr,
UBS, and Applicature [73].
3.3.4. Summary
The use of blockchain technology will improve the flexi-
bility and adaptability of the metaverse data. A blockchain785
must replicate copies of data along the chain resulting in greater
delay when transferring information [74]. As the number of
people in the metaverse increases, the number of blocks must
increase as well, necessitating the use of massive amounts of
computing resources [75]. Users will be charged a higher trans-790
action cost for the validation of shared transactions as a result
of this. Future-generation blockchains have to address this issue
for effective sharing of the data in the metaverse.
3.4. Data Interoperability
3.4.1. Introduction795
Interoperability will be the major driving force behind the
metaverse. A diverse set of applications like finance and health-
care will be able to communicate and exchange information in
the metaverse. The metaverse will be a social and cultural inter-
action platform for virtual worlds. virtual bridges will be cre-800
ated progressively to allow users to keep their avatars and pos-
sessions while easily transferring them between virtual worlds.
A unique set of credentials is issued to the user using an identity
standard, and these credentials can be used across virtual world
borders [76, 59, 77]. This could be the same as our real-life li-805
cense numbers, social security numbers, passport numbers, and
other identification numbers.
3.4.2. Challenges of Data Interoperability in the Metaverse
The metaverse will be created through the fusion of numer-
ous digital realms. The traditional centralized digital platforms810
that are currently available are disjointed and unorganized. In-
dividuals must set up their accounts, avatars, hardware, and
payment infrastructure to participate in different realms [57]. A
user’s options for transferring his or her digital possessions like
NFT and avatar to another digital environment are restricted.815
It is tough to relocate in virtual worlds due to lack of open-
ness, for example, using the same account in decentraland to
roblox is not possible. The potential to use an application in the
virtual world will depend on the interconnection among the vir-
tual worlds. Regardless of where they are located or what tech-820
nology is being utilized, digital world applications should be
able to freely communicate information with one another. The
metaverse interoperability is dependent on the capacity to man-
age the interactions between virtual worlds in an appropriate
manner which is a serious limitation of the traditional approach825
[14].
3.4.3. How blockchain can help
To ensure interoperability between virtual worlds in the meta-
verse, a cross-chain protocol is a perfect solution [78, 79]. This
allows the exchange of possessions like avatars, NFT’s, and830
payment between virtual worlds as depicted in the Fig. 4. This
protocol will provide the groundwork for widespread the meta-
verse adoption. Interoperability between virtual worlds will be
enabled through the use of cross-blockchain technology [80],
eliminating the need for intermediaries in the metaverse. Blockchain835
will make it simple for people and applications to connect in the
metaverse.
3.4.4. Summary
Despite the potential of blockchain in increasing the inter-
operability between virtual worlds in several metaverses, fur-840
ther research is required. The main challenge in cross-blockchain
enabled the metaverse interoperability is the existence of sev-
eral public blockchains in different virtual worlds that do not
share a common language. Various platforms will provide vary-
ing degrees of smart contract capabilities, making adaptation845
difficult. Additionally, the transaction architecture and consen-
sus processes utilized in these virtual worlds vary considerably,
limiting interoperability [81].
3.5. Data Privacy Preservation
3.5.1. Introduction850
The metaverse will make use of advanced human-computer
interface (HCI) technologies, allowing users to participate in
social interactions as well as interact with their virtual surround-
ings [82]. Web 2.0 is centralized and raises concerns about data
privacy. As the Internet of the metaverse, also known as Web855
3.0 grows in scope and complexity, the metaverse will reduce
the boundaries between the real world and the virtual world
[83]. The consequences of the Web 2.0 impact on personal
rights protection are yet to be addressed. Hence, the problem of
data privacy will become even more complicated in upcoming860
Web 3.0. The amount of data generated in the metaverse will
increase dramatically; hence, inadequate security procedures of
applications will raise the likelihood of a data breach [84]. Pri-
vacy preservation is a major cause of concern when it comes to
safeguarding the confidentiality of personal data [42].865
3.5.2. Challenges related to Privacy Preservation in the meta-
verse
The metaverse ecosystem will be difficult to adapt at the ini-
tial stages where the attackers can trick the users and can steal
10
sensitive information. If an artificial intelligence bot like pro-870
mobot is deployed, the user will not be aware of whom they are
dealing with, and the user may believe that they are interact-
ing with a real person, resulting in them being deceived. Per-
sonal identifiable information (PII) is a cause of concern when it
comes to safeguarding the confidentiality of personal data [85].875
Integrating validity information in the metaverse will increase
the difficulty to manage large volumes of the data at the same
time.
3.5.3. How blockchain can help
Blockchain technology gives users of the metaverse the abil-880
ity to control their data through the use of private and public
keys, effectively granting them ownership of their data. In the
blockchain-enabled metaverse, third-party intermediaries are not
permitted to misuse or gain data from other parties. In the
case of personal data kept on the blockchain-enabled the meta-885
verse, the data owners will be able to regulate when and how
a third party can access their information [86]. An audit trail
is included as a standard in blockchain ledgers, ensuring that
transactions in the metaverse are complete and consistent as de-
picted in the Fig. 4. The adoption of zero-knowledge proof on890
the blockchain allows individuals with convenient access to the
identification of essential data in the metaverse while protect-
ing their privacy and maintaining ownership over their posses-
sions. Zero-knowledge proofs are a mechanism of blockchain
by which users can persuade applications that something about895
them is real without disclosing the information [87].
3.5.4. Summary
The adoption of blockchain technology can assist users in
the privacy preservation of their data; but, a single human error,
such as the loss of a private key, has the potential to compro-900
mise the security of blockchain technology and the privacy of
data in the metaverse. In the metaverse, attackers can easily
target third-party applications since they tend to make use of
inadequate security mechanisms, resulting in the compromise
of personal information [88]. There is still a lot of potential for905
an investigation into how blockchain can be used in the meta-
verse to ensure user data privacy.
This section presented the various challenges related to data
acquisition, storage, sharing, interoperability, andprivacypreser-
vation in the metaverse. As depicted in Fig. 4, the blockchain,910
with its mechanisms like blockchain specific validation, decen-
tralised storage, interplanetary file system, cross-chain technol-
ogy, zero-trust mechanism, and encryption, enable the meta-
verse overcome those challenges.
4. Impact of Blockchain on Key Enabling Technologies in915
the Metaverse
Blockchain can enhance the key enabling technologies in
the metaverse that will allow users in participating social and
economic activities without fear of repercussions. The illustra-
tion of blockchain on key enabling technologies in the meta-920
verse is depicted in Fig. 5.
4.1. Blockchain for IoT in the Metaverse
4.1.1. Introduction
The metaverse platform gathers data from a variety of In-
ternet of Things (IoT) devices to ensure that it runs efficiently925
in several applications of the metaverse such as medicine, ed-
ucation, and smart cities [89]. The IoT devices will connect
the metaverse through the use of a diverse range of hardware,
controllers, and physical items. Connecting to the metaverse
and navigating both physically and virtually is made possible930
by IoT devices equipped with specialized sensors. The capac-
ity of IoT devices to perform operations in the metaverse will
be critical to the user’s ability to operate in the metaverse [62].
4.1.2. Challenges related to IoT in the Metaverse
There will be a huge number of connected IoT sensors in935
the metaverse. With so many connected devices, IoT storage
and security are undoubtedly a concern. It is incredibly diffi-
cult to analyze IoT data that is unstructured and real-time [90].
The quality of data can be judged by the amount, precision,
and speed of data [91]. In addition, the metaverse data must940
be error-free for analysis. The use of a centralized strategy is
not advantageous when it comes to storing data across virtual
worlds. If even a single piece of data has been tampered with,
it will harm the entire set of results produced by the IoT de-
vices. The cross-platform capabilities of IoT devices are criti-945
cal for sharing data between virtual worlds [92]. IoT data must
be tracked for safety and regulatory compliance reasons.
4.1.3. How blockchain can help
Blockchain enables the IoT devices in the metaverse to com-
municate data through cross-chain networks, which in turn pro-950
duce tamper-resistant records of shared transactions in virtual
worlds as depicted in Fig. 5 . As a result of blockchain tech-
nology, applications and users will be able to share and access
IoT data without the need for centralized management or con-
trol [93]. To eliminate conflicts and increase confidence among955
the metaverse users, each transaction is recorded and authen-
ticated. In the metaverse, IoT-enabled blockchain enables the
storage of data in real-time. All stakeholders can rely on the
data and take action promptly and efficiently because of im-
mutable blockchain transactions [94]. Blockchain technology960
allows stakeholders to keep track of their IoT data records in
shared blockchain ledgers this will help resolve issues in the
metaverse.
4.1.4. Summary
Blockchain will enable IoT devices to share and store real965
data securely over multiple virtual worlds. Blockchain tech-
nologies require a significant amount of processing power to
keep them running. Blockchains are vulnerable if a small group
of miners controls most of the network’s total mining hash rate.
It is not possible to verify IoT data that is not public due to970
a lack of governance before it is published on the blockchain
in the metaverse. Smart contracts in the metaverse that are exe-
cuted on a distributed transaction ledger may violate the laws. It
is difficult to trace down all IoT transactions involving unlawful
11
Users
IoT
Digital Twins
AI
Big Data
XR Apps
Real-time sensory data
from different devices
Immearuable
range of tasks
Historical data, sensory
data, and models Virtual models
Blockchain
Security
Decentralized
Traceability
Consensus
Metaverse
Smart contract
Immutability
Immersive
experience
Categorized data
Decisions
Multiple data sources
User input, real-time and
historical data
Speech, eye tracking,
gesture, VR/AR
Figure 5: Blockchain for key enabling technologies of the metaverse.
services in the metaverse because of the anonymity provided by975
blockchain technology. While the blockchain’s automatic func-
tion offers numerous advantages, pinpointing which parties are
responsible for specific behaviors remains a difficult challenge
[95]. The blockchain should be regularized to carry out the ex-
pansion of the metaverse.980
4.2. Blockchain for Digital Twins in the Metaverse
4.2.1. Introduction
Digital twins [5] are sophisticated digital representations of
everything in the metaverse, ranging from simple assets to com-
plex products and surroundings. Therefore, anything that is rel-985
evant to the user’s needs could be a component of the ecosys-
tem using digital twins. Two-way IoT connections enable users
to bring their preferred models to life while keeping them in
synchronization with the actual world. The applications of the
metaverse will not be able to work properly unless a connec-990
tion between the physical and digital worlds is established at
the beginning. Digital twins will be important to understand
how the metaverse environment will evolve and will aid in the
prediction of the future [96]. Using digital twins, it is possible
to predict when hardware will need to be serviced or to estimate995
the demands of users before they arrive in the metaverse [97].
4.2.2. Challenges related to Digital Twins in the Metaverse
Digital twin models in the metaverse will be developed us-
ing information obtained from several remote sensors. Digital
twin model accuracy is affected by the quality of the data that1000
is used to create the model. In other words, data provided by
the source must be genuine and up to standard in terms of qual-
ity [98]. Collaboration between digital twins in different virtual
worlds should be possible. It will improve the outcomes of the
metaverse. Digital twins need to interact and link to other dig-1005
ital twins ranging from healthcare to financial markets. Virtual
worlds are constantly changing, and digital twins in the meta-
verse should detect and respond to these changes. The digital
twins should be capable of identifying and fixing errors, which
results in more accurate and consistent communication. When1010
a variety of devices and sensors are brought together to develop
digital twin models using real-time data, it is challenging to
keep data safe from botnets and other malware [99].
4.2.3. How blockchain can help
Blockchain encryption capabilities and historical data trans-1015
parency enable digital twins resistant to attacks and securely
share data [100] over different virtual worlds. Data can be
shared between digital twins in virtual worlds using an intelli-
gent distributed ledger. Real-world objects will be stored on the
blockchain and synchronized to digital twins in the metaverse1020
using an intelligent distributed ledger as depicted in Fig. 5. Ad-
ditionally, the deployment of digital twins on a blockchain will
aid in the resolution of issues related to privacy and data secu-
rity [101]. By merging blockchain with AI, it will be feasible
to track sensor data and produce high-quality digital twins in1025
the metaverse. Every digital twin action in the metaverse will
be recorded as a transaction on the blockchain, which is im-
mutable and requires consensus to change [100].
4.2.4. Summary
The incorporation of blockchain technology into digital twins1030
enables the metaverse stakeholders to efficiently manage data
on a shared distributed ledger while also addressing data trust,
integrity, and safety concerns. Standardization, privacy, and
scalability are all issues that must be addressed for blockchain
to be successfully implemented in digital twin applications in1035
the metaverse. The combination of blockchain, XAI, and feder-
ated learning approaches will provide the explainability of de-
cisions taken with help of sensor data and also ensures data
privacy among the users. It also improve the quality of digital
twins in the metaverse [9].1040
12
4.3. Blockchain for AI in the Metaverse
4.3.1. Introduction
AI is one of the most important enabling technology for the
foundation and development of the metaverse, which helps it
in reaching its full potential. Based on the original image or1045
3D scan, an AI model will analyze user images automatically
and create a very realistic simulated rendition called avatars.
In the metaverse, the representational attributes and features of
avatar affect the overall quality of user experience. Concretely,
AI can plot a variety of facial expressions, feelings, fashions,1050
aging-related characteristics, and so on for the avatar to make
it more dynamic [33]. As a result of significant artificial in-
telligence training, the metaverse will be available to individ-
uals all across the world, regardless of their linguistic compe-
tence [102]. Making the metaverse experience that is both en-1055
tertaining and authentic while salable will be challenging with-
out the use of AI.
4.3.2. Challenges related to AI in the Metaverse
In terms of science and technology, the metaverse repre-
sents a new frontier, and establishing AI there will be a difficult1060
task. It is difficult to track down the ownership of AI-powered
material in the metaverse. Users have no means of knowing
whether they are interacting with a real person or a computer-
generated avatar as depicted in Fig. 5. Users may employ AI
technologies to engage in the metaverse interactions and ille-1065
gally exploit resources, for example, by utilizing AI code to
win games or by stealing resources from other users [103]. It is
also possible that AI will make errors that consequently cause
people to lose faith in the metaverse. Furthermore, it is an ob-
stacle to employ a similar type of blockchain across a variety of1070
AI applications in the metaverse.
4.3.3. How blockchain can help
The encryption provided by blockchain technology facili-
tates the metaverse users with complete control over their data,
making it simple to transfer ownership of AI consent to another1075
party. Users can persuade applications and bots that specific
information about them is accurate without disclosing this in-
formation through the use of zero-knowledge proofs, this pro-
vides the right to use data for AI model training. As a common
feature, blockchain ledgers provide an audit trail, which can1080
be used to check the accountability of all transactions occur-
ring in the metaverse. A zero-knowledge evidence system en-
ables individuals to identify critical facts in the metaverse while
also protecting their privacy and retaining ownership of their
resources from deepfakes and AI simulations [104]. This will1085
prevent AI from exploiting resources in the metaverse.
4.3.4. Summary
The combination of AI and blockchain will protect the highly
sensitive data that AI-driven systems must acquire, store, and
use. The sensitive data and information, from coarse to fine,1090
in the metaverse are substantially better protected as a result of
this approach. Public blockchains are secure and have authentic
data processing, but the collected data are open to all stakehold-
ers in the metaverse. This could be a source of concern and will
also harm the AI models in the metaverse. The attackers will1095
exploit the weakness of AI if there are no blockchain standards
or regulations in place. Remarkably, it is necessary to intro-
duce a cross-chain converter that enables AI applications to be
familiar with the metaverses built on different blockchains.
4.4. Blockchain for Big Data in the Metaverse1100
4.4.1. Introduction
Data in the metaverse is more diverse and arrives in greater
volumes and with high velocity than data in the real world.
When new data sources in the metaverse are discovered, big
data techniques in the metaverse will be used to assemble larger1105
and more sophisticated datasets. The massive amount of data
generated by the metaverse will be useful for a wide range of ac-
tivities, ranging from customer service to data analytics [105].
Big data will provide new insights that will lead to the creation
of new opportunities and business models in the metaverse.1110
4.4.2. Challenges related to Big Data in the Metaverse
Although data storage technologies have advanced, the amount
of data has progressively doubled and will continue to increase
in the metaverse. Keeping up with the amount and speed at
which data is generated in the metaverse is a complicated task1115
to accomplish. The heterogeneity of the data generated by the
metaverse applications is also a big challenge. The ability to put
data to good use in the metaverse is what makes it valuable, and
curation is the method by which this is accomplished. Data col-
lection and organization that is essential to the consumer in the1120
metaverse requires a large investment of time and effort. Data
scientists will spend the majority of their time preparing and
organizing data for it to be used by stakeholders [15]. Finally,
big data technology is progressing at a rapid speed. Keeping
up with the latest big data technological developments in the1125
metaverse is a never-ending challenge.
4.4.3. How blockchain can help
The use of blockchain technology will aid in the collection
of data from trusted data sources, hence reducing the amount of
improper data obtained as depicted in Fig. 5. The data owners1130
will have total control over their data, and any data manipula-
tion by a third party will be restricted. This assures that data
flows in the metaverse are of a high standard of quality [106].
Due to the decentralized nature of blockchain technology, data
scientists in the metaverse will be able to communicate and col-1135
laborate on data cleaning, which will significantly reduce the
time and expense associated with classifying data and creating
datasets for analytics applications, as well as the risk of data
contamination. Because of the immutability of the blockchain,
it will not be feasible to tamper with the data because it will be1140
duplicated throughout the network [107]. This will improve the
availability of data for stakeholders of the metaverse.
13
4.4.4. Summary
Blockchain holds a great deal of potential for the future of
big data analytics. Users will be able to maintain complete con-1145
trol over their personal information and financial activities in
the metaverse. There will be no need for a third party to obtain
trusted data and to label that data because of the blockchain.
Some of the issues, like consensus models, the cost of mining
blocks, and the verification of transactions are still challenging1150
[106]. Blockchain offers solutions that require major changes
to existing systems or the complete replacement of these sys-
tems. As a result, it will be hard and time-consuming to change
the whole system. Even though blockchain integration with the
metaverse is still in its early stages, these issues will be resolved1155
in the future, paving the way for a wide range of new and excit-
ing opportunities.
4.5. Blockchain Multi-sensory XR Applications, Holographic
Telepresence in the Metaverse
4.5.1. Introduction1160
The metaverse provides immersive, and real-world experi-
ences through the use of technology like holographic telepres-
ence and augmented reality applications as depicted in Fig. 5.
These applications incorporate audio, video, cognition, and other
components. They provide a real-time representation of vir-1165
tual and physical objects in the metaverse. XR applications
will make use of sensors to create a more realistic experience
by incorporating real-world objects [108]. As a result of these
advancements, holographic telepresence and multi-sensory XR
applications enable a user to experience both the real and virtual1170
worlds concurrently.
4.5.2. Challenges related to Multi-sensory XR Applications, Holo-
graphic Telepresence in the Metaverse
XR technologies like VR, AR, and holographic telepres-
ence are key enabling technologies in the metaverse. However,1175
they may also raise personal and societal concerns. Using the
information gathered from these technologies, the companies
will be able to develop a recommendation system. The quality
of these recommendation systems in the metaverse can be in-
fluenced by behavioral data collected from a variety of sources.1180
This technology necessitates enormous amounts of data stor-
age, which must be readily accessible at all times for the users
in the metaverse. Sensitive data like biometric information col-
lected by AR/VR devices can be used to identify users and infer
additional information about them in the virtual world [33]. The1185
metaverse must ensure the privacy of such sensitive informa-
tion of the users. These gadgets exchange or transfer a massive
amount of data between virtual worlds. The metaverse must
enable data transparency when various stakeholders and third
parties are involved in the data sharing process [109].1190
4.5.3. How blockchain can help
In the metaverse, a blockchain based distributed ledger would
enable the validation of holographic telepresence and other XR
applications records, as well as trace the source of erroneous
data. This will help build a more accurate recommendation1195
system. Holographic telepresence and other XR applications
will find it easier to share data securely between virtual worlds
with the zero-trust mechanism and cross-chain technology of
the blockchain [109]. For XR applications and holographic
telepresence, the inter-planetary file system provided by the1200
blockchain ensures data integrity. The data collected by these
devices and saved on a blockchain will be immutable due to
the consensus mechanism. Blockchain ensures trust among
AR/VR stakeholders by making the verification and ownership
transfer of digital assets transparent [110].1205
4.5.4. Summary
Multi-sensory XR applications combined with holographic
telepresence and blockchain technology will help to integrate
digital economies into unified platforms where assets and pay-
ments in the metaverse can be managed efficiently and unam-1210
biguously. VR/AR technology will not have the global reach of
smartphones or computers in the foreseeable future. A concern
and a problem for blockchain will be the use of enhanced AI
deep fakes [111], which must be addressed by new emerging
blockchain platforms.1215
IoT devices, digital twins, and XR applications will gener-
ate big data in the metaverse. Blockchain will assist these tech-
nologies in high quality, secured acquisition of authentic data in
the metaverse. Blockchain will store and handle the big data in
the metaverse data in a secured manner through the immutabil-1220
ity and transparency properties offered by the blockchain. En-
abling technologies like IoT, digital twins, and XR will be ben-
efited considerably in terms of higher data transparency and
adaptability provided by the blockchain. NFTs and the real
estate or the digital assets produced using digital twins in the1225
metaverse will become interoperable because of the zero-trust
and cross-chain mechanisms of the blockchain. The metaverse-
enabled technologies will be benefited from the high degrees
of data privacy due to anonymity, audits, authentication, anti-
tampering, and access control offered by blockchain. Table 21230
summarizes the impact of the blockchain on the technical as-
pects and various enabling technologies of the metaverse.
This section presented various challenges related to the inte-
gration of various enabling technologies like IoT, digital twins,
AI, big data, and XR in the metaverse. As depicted in Fig.1235
5, blockchain, with its features like security, traceability, im-
mutability, decentralised storage, smart contracts, and consen-
sus, will help the metaverse overcome integration challenges
with various enabling technologies.
5. The Metaverse Projects1240
This section briefly introduces some well-known the meta-
verse projects: Decentraland, Sandbox, Axie Infinity, and Illu-
vium, which have exploited blockchain as the core technology
of the metaverse foundation and development, and addition-
ally to deliver multifarious blockchain-based services and ap-1245
plications in the virtual world, from real estate to E-commerce
and real estate. The landscapes inside the virtual worlds of the
projects are shown in Fig. 6.
14
Figure 6: Inside the virtual worlds of different metaverse projects (left to right): Decentraland, Sandbox, Axie Infinity, and Illuvium.
Table 2: Impact of Blockchain for Technical Aspects in the Metaverse
Technical Perspec-
tive
Data Acquisition Capacity
Data Storage
Data Sharing
Data Interoperability
Data Privacy Preservation
IoT H L H L H
Digital Twins H L H M H
XR Applications H M H L H
AI L M L L H
Big Data H H L L H
LLow Impact MMedium Impact HHigh Impact
Decentraland3: Decentraland is a virtual reality platform
powered by the Ethereum blockchain, which allows users to ex-1250
perience, create, and monetize economic assets, hyperreal con-
tents, and applications. Land in Decentraland is permanently
owned by the community with full surveillance and control over
their creative activities. In the virtual world of Decentraland,
a virtual land is identified uniquely as a non-fungible, trans-1255
ferrable, and scare digital asset stored in the Ethereum smart
contract, which can be claimed on the blockchain-based ledger
with ERC-20 (Ethereum Request for Comments 20) tokens call
MANA. Different from other traditional virtual worlds and so-
cial networks, Decentraland is not managed and supervised by1260
any centralized organization; that is, no single agent has permis-
sion to change the rules of software, content, economic mecha-
nism, or prevent others from accessing the world, trading digital
products, and providing services.
Decentraland is with the proof of concept to enable the own-1265
ership of digital real estate to the user on the Ethereum blockchain,
wherein its blockchain payment network is built to obtain short-
to-medium-term scalability. This payment network is with low
fees to encourage the economic development of the Decentra-
land metaverse. In the perspective of user cases, Decentraland1270
considers content curation, advertising, social (forums, chat groups,
3https://decentraland.org/
and multiplayer games), applications (games, gambling, and
dynamic 3D scenes with scripting language toolset), and oth-
ers (such as therapy, 3D design, education, and virtual tourism).
In the perspective of architecture, the Decentraland protocol is1275
comprised of three layers: consensus layer, land content layer,
and real-time layer besides two supportive systems, including
payment channel infrastructure and identity system. With the
Ethereum smart contract to maintain a ledger of ownership for
a piece of land in the virtual world, Decentraland remarks non-1280
fungible digital assets LAND which is generated by burning
MANA tokens via the LAND smart contract. For ownership
identification, Decentraland uses the Ethereum Name Service
to create of a layer of ownership over in-world items.
Sandbox4: As built on the Ethereum blockchain, Sandbox1285
is a user-generated the decentralized metaverse, in which users
can build, own, and monetize immersed gaming experiences
using SAND, its native platform’s utility token with ERC-20.
Inspired by Minecraft5and Roblox6, Sandbox uplifts the gam-
ing experience from a 2D mobile pixel environment to a fully1290
3D world by using a voxel gaming platform. In the Sand-
box metaverse, users can freely create and animate 3D objects
(such as people, animals, buildings, and tools) by VoxEdit, a
built-in voxel gaming package, with true ownership as NFTs.
These creations can be traded on the Sandbox marketplace as1295
game assets and the creators can receive their reward/incentive
by SAND tokens (compatible with ERC-721 and ERC-1155).
With the utility of NFTs, the Sandbox users will receive the fol-
lowing benefits: (i) true digital ownership (every game item can
be tokenized to easily own, trade, and sell), (ii) security and im-1300
mutability (the risks of fraud and theft are minimized with the
distributed ledger of blockchain technology), (iii) trading (ulti-
mate digital asset control without in-game value abandon), and
(iv) cross-platform interoperability (in-game items can be avail-
able for usage in different games that allow it). The Sandbox1305
metaverse adopts The InterPlanetary File System to store the
actual digital assets and ensure the assets can be modified with-
out owner permission. The main concern of Ethereum chain-
aided projects is scalability, which motivates the Sandbox team
to look at layer-2 solutions (scale an application by handling1310
transactions offthe Ethereum Mainnet while taking advantage
of decentralized security).
Axie Infinity7: As one of the revolutionary Play-to-Ern meta-
verse projects, Axie Infinity builds a crypto-meet-Pok´
emon game
4https://www.sandbox.game/en/
5https://www.minecraft.net/en-us
6https://www.roblox.com/
7https://axieinfinity.com/
15
universe with fantasy creatures, called Axies, that players can1315
collect, raise, breed, and battle for building their Axies king-
doms. Like Decentraland and Sandbox, Axie Infinity has a
user-centric economy system that allows players to truly own,
sell, buy, and trade in-game resources over gaming activities
and contributions to the ecosystem. A key difference between1320
Axie and other traditional games is that the blockchain-based
economic mechanism of the Axie metaverse allows players to
increase their digital assets by improving in-game skills to reach
certain levels. Players can have fun with many play modes
(PvP - player versus player and PvE - player versus environ-1325
ment) and numerous tournaments while earning in-game re-
sources for trading with real monetary value possibly. Axie In-
finity Shards (AXS), the ERC-20 governance token of the Axie
metaverse, can be claimed as rewards when players stake their
AXS tokens, play the game, and participate in governance ac-1330
tivities. Furthermore, they can earn AXS tokens when playing
different games involved by Axie Infinity Universe and creat-
ing user-generated content. Axies creatures and other virtual
real estates can be bought, sold, and traded via an in-game mar-
ketplace in the form of NFTs. Remarkably, most transactions1335
are processed on an Ethereum-linked sidechain, called Ronin,
which is specially designed to achieve lower fees than the stan-
dard Ethereum blockchain. Besides AXS, Axie Infinity has a
secondary token, namely Small Love Position (SLP), which is
awarded to players via in-game activities.1340
Illuvium8: Often touted as the first open-world fantasy bat-
tle game metaverse built on the Ethereum blockchain, Illuvium
can provide a source of entertainment to regular gamers and de-
centralized finance (DeFi) users through a range of collecting
and trading features. The virtual world of Illuvium is inhabited1345
by fantasy creatures, called Illuvials, which can be captured by
players when defeating them in casual battles. From then on,
these Illuvials become a loyal team of the player’s collection
and be carried out to combat against other players via a ran-
dom PvP gameplay. In other words, the Illuvium’s game is1350
a combination of an open-world exploration game and a PvP
battle game, where players can immerse different gameplays,
i.e., freely exploring the virtual world while planning battle stat-
ics. Each Illuvial is associated with a unique NFT and can be
traded on the in-game marketplace or external exchange plat-1355
form without gas fees.
The native token used within the Illuvium ecosystem is ILV
which has three main use cases: rewarding players for in-game
achievements, presenting players for their vault (a private wallet
of each user) distribution, and participating in governance ac-1360
tivities of the game via decentralized autonomous organization
(DAO). To obtain the scalability of applications with NFT func-
tionality, Illuvium leverages Immutable X, a layer-2 Ethereum
scaling solution that allows users to trade NFTs with zero gas
fees and instant transaction finality by using an innovative tech-1365
nique known as Zero-Knowledge Rollup. Besides layer-2 in-
tegration, Illuvium is featured by a built-in decentralized ex-
change platform that facilitates trading activities of Illuvial NFTs.
8https://www.illuvium.io/
6. Conclusion and Research Directions
The paper has comprehensively investigated and analyzed1370
the roles and impacts of blockchain for the foundation and de-
velopment of applications and services in the metaverse. The
fundamental concepts of blockchain and the metaverse were
sketched at the beginning of this work, along with the role of
blockchain regarding the foundation and development of the1375
metaverse. Later in this work, several prominent technical as-
pects and use cases of blockchain in the metaverse were inves-
tigated exhaustively besides the insightful challenge analysis
and applicability discussion given. Finally, some technical im-
provements of blockchain were provisioned for the metaverse,1380
which in turn enhances the performance and practicality of po-
tential applications and services in the virtual world. Besides
making the conclusion, we sketch out some future research di-
rections as below.
Relying on the systematic investigation of blockchain for1385
the metaverse in both the technical and use case perspectives,
blockchain had showed a great potential to revolutionize the
immersive experience with various applications and services
built in the virtual world. Many technical and applicable as-
pects of all current blockchain versions have been attracting1390
much more research activities, including consensus algorithms,
network management, and blockchain interoperability. As con-
sensus algorithms ensure the agreement of states of certain data
among authorized nodes in a distributed network, numerous
variations of consensus mechanisms have been introduced to1395
achieve high throughput and low latency, but security, scalabil-
ity, and decentralization could not be obtained concurrently [112].
In this context, it is necessary to develop and sharpen some hy-
brid innovative consensus algorithms (e.g., Proof-of-Capability,
Proof-of-Burn, and Leased Proof-of-Stake) to effectively han-1400
dle the above-mentioned issues. As a serious global issue no-
ticed by many governments and blockchain communities, high
energy consumption and greenhouse gas emission derived by
the operation of a large number of participating nodes in a net-
work has caused negative climate and environmental impacts.1405
For a sustainable solution, the Stellar consensus protocol [113]
allows authenticating transactions based on a set of trustwor-
thy nodes rather than running the authentication process for the
whole network as PoW or PoS algorithm, which in turn accel-
erates the speed and reduces energy in use.1410
Nowadays, numerous networks and blockchains have been
designed for specific applications and services under the um-
brella of different community organizations and government
departments; therefore, interconnecting existing and new chains
is necessary to boost the development of emerging technolo-1415
gies in the metaverse. Cross-chain is introduced as the ulti-
mate solution to obtain the interoperability between different
chains, which allows users to execute transactions (with value
and information) successfully between different blockchain net-
works [114]. For instance, users would be able to send the infor-1420
mation from an Ethereum blockchain to a Polygon blockchain
and vice versa. This interoperability technique also actuates
the increasing development of fully decentralized systems with
cross-chain bridges. For a long-term evolution of blockchain
16
Table 3: Comparison of the Metaverse projects.
Project Decentraland Sandbox Axie Infinity Illuvium
Definition 3D blockchain meta-
verse allows user to
create, buy, sell, and
trade virtual plots of real
estate
Blockchain-based meta-
verse for creating, buy-
ing, selling digital assets
and empowering a play-
to-earn gaming economy
An online game uni-
verse revolving around
Pok´
emon creatures, in
which players collect
virtual pets with aspi-
rations to battle, breed,
collect, raise, and build
ecosystem.
As known as the first
blockchain-based AAA
video game devel-
oped on the Ethereum
blockchain by a decen-
tralized autonomous
organization (DAO).
Blockchain
adoption
Ethereum Ethereum Ethereum and Binance
smart chain
Ethereum
Token
standard
ERC-20, ERC-721 ERC-20, ERC-721,
ERC-1155
ERC-20, BEP-20 ERC-20
Crypto-
currency
MANA (native token)
and LAND (as NFT).
SAND (native token),
ASSETS (as NFT), and
LAND (as in-game to-
ken).
AXS (native token) and
SLP (reward token in
game).
ILV (native token) and
sILV (as in-game token).
Use cases Application (create
applications and 3D
scenes), content curation
(grow organic com-
munities), advertising
(buy spaces and setup
billboards), digital col-
lectiables (trade NFTs),
social (experience more
interactive socializing
manners).
There are five use
cases in the Sandbox
meteverse: purchase
(for required services),
trade (lands, assets, and
gems), play (built-in
games), create (games
and assets), and gov-
ernence (votes, staking,
and curation).
Attract players with an
active community and
thriving ecosystem over
in-game reward tokens
by offering a fun gam-
ing experience to be-
come immersed in.
Some use cases within
the game and ecosys-
tem: reward (receive
tokens for successes
and achievements when
playing games), stak-
ing (earn tokens when
staking native tokens),
and voting proposal via
its decentralized au-
tonomous organization.
Addressed
challenge
Decentraland partners
with Polygon blockchain
(as sidechain) to handle
transaction fee and pro-
cessing speed to address
the native problems
of the main Ethereum
blockchain. It is noted
that the sidechain is kept
interoperable with the
Ethereum’s mainchain.
The Ethereum
blockchain provides
three main benefits: ease
of use (the largest num-
ber of developers allows
well-established stan-
dards, practice’s, and
supports), robustness
(wide adoption makes
network more securely),
and interoperability (can
build and interact with
other chains). However,
Sandbox has a plan
to move to Polygon
to overcome high fees
and slow processing of
Ethereum.
To process transactions
instantly and allow play-
ers to transact tokens
and NFTs without using
the Ethereum blockchain
(high fee and slow),
Axie Infinity addition-
ally leverages Ronin
sidechain to reduce cost
and speed of transactions
to service an increasing
number of players.
Besides the main devel-
opment on the Ethereum
blockchain, the Illuvium
metaverse projects fur-
ther considers a layer-2
scaling solution known
as Immutable X to
accelerate transactions
for marketplaces, games,
and built-in applica-
tions on Ethereum.
Zero-knowledge rollups
are adopted to bundle
transactions together for
protecting privacy and
speeding up processing
speed as well.
to reach multi-chain interoperability, omni-chain [115], which1425
is defined as a blockchain-as-a-service platform to interact with
a wide variety of enterprise networks, can provide blockchain-
based applications and services (including asset management,
smart contract, transaction management, and shared data ledger)
with many appreciated benefits, such as greater transparency,1430
enhanced security, improved traceability, and better efficiency
and speed.
In traditional organizations adopting classical company hi-
erarchy, most of the important decisions have been made by
directors and area managers, which are usually risky and faulty1435
due to human mistakes. To overcome these problems, DAOs
17
are introduced as the next generation of organizational struc-
ture, which involves a group of incognito people sharing the in-
formation together according to a self-enforcing protocol [116].
DAOs are governed by the smart contract algorithms that live1440
on a blockchain network to reduce transaction management fees
while presenting better transparency and incorruptibility. All
governance rules of a DAO are recorded on a transparent, se-
cure, and open-source ledger of the blockchain network. No-
ticeably, native token stakeholders do not have permission to1445
override rules, but they can use tokens to vote proposals via
DAO’s consensus rules. Concerning shareholders’ common goals,
the immutability of smart contracts in DAOs will preserve the
economic profit and other interests of any governed organiza-
tions over a tamper-proof shared ledger, where all activities and1450
transactions on the network will be recorded. In the future, ser-
vices (e.g., DeFi) and products (e.g., NFT) in the metaverse can
be developed and maintained automatically by DAO, in which
smart contracts and consensus rules will govern all major func-
tionalities.1455
Acknowledgement
This work is partly supported by the CONFIDENTIAL-6G
project (grant no. 101096435) and the CONNECT research
center.
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20
Thien Huynh-The received the B.S. de-
gree in electronics and telecommunica-1835
tion engineering from Ho Chi Minh City
University of Technology and Education,
Vietnam, in 2011, and the Ph.D. degree
in computer science and engineering from
Kyung Hee University (KHU), South Ko-1840
rea, in 2018. From March to August
2018, he was a Postdoctoral Researcher
with KHU. He is currently a Postdoctoral
Research Fellow with ICT Convergence Research Center at
Kumoh National Institute of Technology, South Korea. He is1845
awarded with the Superior Thesis Prize by KHU in 2018 and
the Golden globe award 2022 for Vietnamese young scientists
by Ministry of Science and Technology of Vietnam in 2020.
His current research interest includes radio signal processing,
digital image processing, computer vision, wireless communi-1850
cations, and deep learning.
Thippa Reddy Gadekallu is currently
working as an Associate Professor in
School of Information Technology and1855
Engineering, Vellore Instituite of Tech-
nology, Vellore, Tamil Nadu, India. He
obtained his B.Tech. in CSE from Nagar-
juna University, India, M.Tech. in CSE
from Anna University, Chennai, Tamil1860
Nadu, India and completed his Ph.D in
VIT, Vellore, Tamil Nadu, India. He has
more than 14 years of experience in teaching. He has than
100 international/national publications in reputed journals and
conferences. Currently, his areas of research include Ma-1865
chine Learning, Internet of Things, Deep Neural Networks,
Blockchain, Computer Vision. He is an editor in several pub-
lishers like Springer, Hindawi, Plosone, Scientific Reports (Na-
ture), WIley. He also acted as a guest editor in several reputed
publishers like IEEE, Springer, Hindawi, MDPI. He is recently1870
recognized as one among the top 2% scientists in the world as
per the survey conducted by Elsevier in the year 2021.
Weizheng Wang received the B.S. degree
in software engineering from Yangzhou1875
University, Yangzhou, China, in 2019,
the M.S. degrees in computer science
and engineering from the University of
Aizu, Aizu-Wakamatsu, Japan, in 2021.
Now he is a Research Associate in Uni-1880
versity of Aizu and pursuing the Ph.D.
degree at the Department of Computer
Science, City University of Hong kong,
Hong Kong, China. His research interests include applied cryp-
tography, blockchain technology and IoT system.1885
Gokul Yenduri is pursuing his Ph.D.at
School of Information Technology and
Engineering, Vellore Institute of Technol-
ogy, Vellore, Tamil Nadu, INDIA. He ob-1890
tained his Bachelors in Computer Science
and Engineering from Acharya Nagar-
juna University,Guntur, INDIA and Mas-
ter of Technology in Information Tech-
nology (Networking) from Vellore Insti-1895
tute of Technology, Vellore, Tamil Nadu, INDIA. He has more
than 9 years of experience in teaching. He has published articles
in reputed journals/conferences. His areas of research include
Machine Learning, Software Engineering, Blockchain, Cryp-
tography, Network security. He is also serving as a reviewer in1900
many reputed journals like Journal of King Saud University -
Computer and Information Sciences, Expert Systems, Wireless
Communications and Mobile Computing, Human-centric Com-
puting and Information Sciences, Soft Computing, Journal of
Circuits, Systems, and Computers, Computational Intelligence1905
and Neuroscience, PLOS ONE, Security and Communication
Networks, etc.
Pasika Ranaweera is a Post-Doctoral
Researcher in the School of Computer1910
Science, University College Dublin, Ire-
land, since January 2023. He graduated
from the University of Ruhuna, Sri Lanka,
in 2010 with honors and received the
Lanekassen scholarship for pursuing the1915
Master Degree in Information and Com-
munication Technology (ICT) in 2013
from the University of Agder, Norway. Pasika completed his
Ph.D. from University College Dublin, Ireland, on improving
the security of service migrations of MEC in 2023 and awaits1920
his viva. Prior to his Ph.D., he served as a lecturer attached
to the Department of Electrical and Information Engineering,
Faculty of Engineering, University of Ruhuna, Sri Lanka, from
2014 to 2018. Pasika is focused on enhancing the security mea-
sures in 5G and beyond 5G mobile networks, while his main1925
research focus is directed at Federated Learning-based secu-
rity issues and how to overcome them utilizing Blockchain.
His additional research directives extend to lightweight secu-
rity protocols, formal verification, security, service quality op-
timization, 5G and MEC integration technologies (SDN, NFV,1930
Blockchain), privacy preservation techniques, and IoT security.
In addition to the research work, he serves as a reviewer for
IEEE IoT journal, IEEE Access, IEEE Communication Maga-
zine, IEEE IoT Magazine, SN Computer Science, and various
IEEE-hosted conferences and workshops under the IEEE Com-1935
munication Society (also a member of IEEE ComSoc).
21
Quoc-Viet Pham received the B.S. de-
gree in electronics and telecommunica-
tions engineering from the Hanoi Univer-1940
sity of Science and Technology, Vietnam,
in 2013, and the Ph.D. degree in telecom-
munications engineering from Inje Uni-
versity, Republic of Korea, in 2017. He
has been a Research Professor with Pu-1945
san National University, Republic of Ko-
rea, since Feb. 2020. He is specialized in
applying convex optimization, game theory, and machine learn-
ing to analyze and optimize edge computing and future wireless
communications. He has been granted the Korea NRF Funding1950
for outstanding young researchers for the term 2019ˆ
a€“2024.
He has been a TPC/TPC chair for leading conferences, includ-
ing IEEE ICC, IEEE VTC, and EAI GameNets. He is an
editor of the Journal of Network and Computer Applications
(Elsevier), an associate editor of the Frontiers in Communica-1955
tions and Networks, and a lead guest editor of the IEEE Inter-
net of Things Journal. He was also the recipient of the Best
Ph.D. Dissertation Award in engineering from Inje University
in 2017, the Top Reviewer Award from the IEEE Transactions
on Vehicular Technology in 2020, the golden globe award 20211960
from the Ministry of Science and Technology (Vietnam), and
the award for outstanding contributions and research excellence
from Minister of Education (Korea) in 2021.
Daniel Benevides da Costa was born in1965
Fortaleza, Cear ˆ
A´a, Brazil, in 1981. He
received the B.Sc. degree in Telecom-
munications from the Military Institute
of Engineering (IME), Rio de Janeiro,
Brazil, in 2003, and the M.Sc. and Ph.D.1970
degrees in Electrical Engineering, Area:
Telecommunications, from the University
of Campinas, SP, Brazil, in 2006 and
2008, respectively. His Ph.D thesis was awarded the Best
Ph.D. Thesis in Electrical Engineering by the Brazilian Min-1975
istry of Education (CAPES) at the 2009 CAPES Thesis Con-
test. From 2008 to 2009, he was a Postdoctoral Research Fel-
low with INRS-EMT, University of Quebec, Montreal, QC,
Canada. From 2010 to 2022, he was with the Federal Univer-
sity of Cear ˆ
A´a, Brazil. From January 2019 to April 2019, he1980
was Visiting Professor at Lappeenranta University of Technol-
ogy (LUT), Finland, with financial support from Nokia Foun-
dation. He was awarded with the prestigious Nokia Visit-
ing Professor Grant. From May 2019 to August 2019, he
was with King Abdullah University of Science and Technol-1985
ogy (KAUST), Saudi Arabia, as a Visiting Faculty, and from
September 2019 to November 2019, he was a Visiting Re-
searcher at Istanbul Medipol University, Turkey. From 2021 to
2022, he was Full Professor at the National Yunlin University
of Science and Technology (YunTech), Taiwan. Since 2022, he1990
is with the AI Telecom Research Center at the Technology In-
novation Institute (TII), in Abu Dhabi, UAE. He is Editor of
several IEEE journals and has acted as Symposium/Track Co-
Chair in numerous IEEE flagship conferences.
1995
Madhusanka Liyanage (Senior Mem-
ber, IEEE) received his B.Sc. degree
(First Class Honours) in electronics and
telecommunication engineering from the
University of Moratuwa, Moratuwa, Sri2000
Lanka, in 2009, the M.Eng. degree
from the Asian Institute of Technol-
ogy, Bangkok, Thailand, in 2011, the
M.Sc. degree from the University of Nice
Sophia Antipolis, Nice, France, in 2011,2005
and the Doctor of Technology degree in communication engi-
neering from the University of Oulu, Oulu, Finland, in 2016.
From 2011 to 2012, he worked a Research Scientist at the I3S
Laboratory and Inria, Shopia Antipolis, France. He is currently
an assistant professor/Ad Astra Fellow at School of Computer2010
Science, University College Dublin, Ireland. He is also act-
ing as an adjunct Processor at the Center for Wireless Com-
munications, University of Oulu, Finland. He was also a re-
cipient of prestigious Marie SkÅodowska-Curie Actions Indi-
vidual Fellowship during 2018-2020. During 2015-2018, he2015
has been a Visiting Research Fellow at the CSIRO, Australia,
the Infolabs21, Lancaster University, U.K., Computer Science
and Engineering, The University of New South Wales, Aus-
tralia, School of IT, University of Sydney, Australia, LIP6,
Sorbonne University, France and Computer Science and En-2020
gineering, The University of Oxford, U.K. He is also a senior
member of IEEE. In 2020, he has received ”2020 IEEE Com-
Soc Outstanding Young Researcher” award by IEEE ComSoc
EMEA. Dr. Liyanage’s research interests are 5G/6G, SDN, IoT,
Blockchain, MEC, mobile and virtual network security.2025
22
