Decentralized Car Rental System: Ensuring Security with Blockchain

Smart Contracts

Chiraz El Hog

1, 2 a

, Raoudha Ben Djemaa

3 b

, Rania Aldaas

, Buthainah Alnaeem

, Rand Alageeli

Atheer Almutiri

and Hadeel Alharbi

Department of Computer Science, College of Computer, Qassim University, Buraydah, 52571, Saudi Arabia

ISSAT, University of Sousse, Tunisia

ISITCOM, University of Sousse, Tunisia

ﬁ

Keywords:

Blockchain, dApps, Smart Contract, Data Security, Data Privacy, Car Rental.

Abstract:

In today’s fast-paced digital economy, efﬁciency and trust are crucial, particularly in ﬁnancial transactions

and resource-sharing services. The growing interest in car-sharing platforms and blockchain technology has

paved the way for decentralized solutions that enhance security, transparency, and automation. This paper

presents a decentralized car rental solution built on blockchain technology, using smart contracts to ensure

secure, tamper-proof, and trustful transactions. The proposed system allows users to browse and rent available

vehicles, select suitable options based on their needs, and set rental terms seamlessly. Furthermore, car owners

and businesses can rent out their unused vehicles for rent while specifying features, images, and pricing. The

rental process is governed by blockchain-based identity management and smart contract enforcement, elimi-

nating intermediaries and reducing operational risks. A key focus of this work is privacy and data protection.

The system incorporates cryptographic techniques, access control mechanisms, and smart contract security

best practices to mitigate risks such as fraud, unauthorized access, and data manipulation. Using blockchain

immutability, decentralized identity veriﬁcation, and secure payment channels, the platform improves user

trust and prevents common vulnerabilities seen in traditional rental systems. Through this blockchain-based

approach, we provide a secure, efﬁcient, and transparent alternative to conventional car rental services, foster-

ing greater trust among users while minimizing costs and enhancing operational efﬁciency.

1 INTRODUCTION

Intelligent Transportation Systems play a key role

in transportation and trafﬁc management systems

around the world. They are a combination of ad-

vanced information and communication technologies

used in transportation to enhance safety, efﬁciency,

and improve driver experience(Souki et al., 2023).

Car sharing and rental are signiﬁcant subﬁelds of

transportation systems that use these technologies to

simplify vehicle access and use. Currently, most ex-

isting car rental systems are centralized. They rely

on third parties to manage the rental process between

customers and car owners. The customer must there-

fore select the right vehicle in person at the rental of-

ﬁce. The rental agreement is achieved by accepting

https://orcid.org/0000-0002-0367-5439

https://orcid.org/0000-0002-7831-112X

the rental fees and terms of a contract created by the

middleman along with the need that a driver‘s license

and national identiﬁcation be shown. However, many

issues arise with this approach, such as the high leas-

ing costs resulting from the commission of the mid-

dleman and the possibility of misuse of the customer’s

personal papers due to the lack of conﬁdentiality guar-

antee.

Furthermore, contract management remains a sig-

niﬁcant challenge for companies that use traditional

paper contracts or digital systems. Paper contracts

are prone to damage, forgery, and loss, making them

unreliable for long-term records and signiﬁcantly in-

creasing the risk of fraud. Although digital contracts

offer greater efﬁciency, they remain susceptible to

hacking and data manipulation, posing a risk of se-

curity breaches and unauthorized alterations. Fur-

thermore, contract mismanagement, such as delayed

cancellation of a rental agreement, can lead to du-

1110

El Hog, C., Ben Djemaa, R., Aldaas, R., Alnaeem, B., Alageeli, R., Almutiri, A. and Alharbi, H.

Decentralized Car Rental System: Ensuring Security with Blockchain Smart Contracts.

DOI: 10.5220/0013505400003929

Paper published under CC license (CC BY-NC-ND 4.0)

In Proceedings of the 27th International Conference on Enterprise Information Systems (ICEIS 2025) - Volume 1, pages 1110-1120

ISBN: 978-989-758-749-8; ISSN: 2184-4992

plicate bookings, where a vehicle is rented to a new

customer while still being registered under the pre-

vious renter. Moreover, if any ﬁnes or penalties (for

example, trafﬁc violations) occur during this period,

they can be incorrectly assigned to the previous cus-

tomer, leading to conﬂicts, ﬁnancial liabilities, and

unfair charges. Managing their cars once they are

rented out presents serious difﬁculties for car rental

companies as well. Without adequate tracking, a

car could be damaged or utilized for illicit purposes

without the company’s knowledge. Customers may

exceed the predetermined mileage limits,Customers

may exceed the predetermined mileage limits, violat-

ing rental terms and ruining trust between the parties.

Blockchain technology is a decentralized peer-to-

peer network composed of a series of blocks where

data are stored. These blocks are linked based on

cryptographic hash methods(Souei et al., 2023). It

is a particularly promising and revolutionary tech-

nology because it helps reduce security risks, elimi-

nate fraud, and bring transparency in a scalable way

[15]. It is also considered ideal for delivering infor-

mation because it provides immediate, shared, and

completely transparent information stored on an im-

mutable ledger that can be accessed only by permit-

ted network members. This technology cancels the

participation of a third party between the seller and

the buyer. In fact, participants are connected in a

peer-to-peer network, and data are shared in a dis-

tributed manner. It is a series of blocks closely re-

lated to each other. Each block has a hash that is

like its own ﬁngerprint, which changes with chang-

ing content of the block, and also contains the hash

of the preceding block. Whereas, when the content of

the block is modiﬁed, it will appear that it has tam-

pered because it will change its hash and the hash that

follows it all. The strength of the blockchain lies in

its features such as immutability, decentralization, se-

curity, and anonymity. In fact, each node has copies

of all transactions, but with encrypted data. There-

fore, blockchain improves trust across a business net-

work (Shanker, 2019). With the advent of blockchain

technology, smart contracts appeared, which are piece

of code executed on the blockchain to automatically

trigger transactions upon the occurrence of predeﬁned

events (Souei et al., 2023). The smart contract is im-

mutable; therefore, it cannot be modiﬁed once cre-

ated. The smart contract is executed automatically

(self-executing code) when the agreement conditions

are met. To ensure that a blockchain can execute a

contract between two parties safely without the need

for a lawyer or any middleman, smart contracts can

hold the agreed-upon funds. Once the speciﬁed con-

ditions are met, the funds are automatically trans-

ferred to the rightful recipient. Many research stud-

ies have been conducted in academia and industry to

take advantage of these technologies in various areas.

Especially, in the domain of car sharing and rental,

some solutions were proposed (Auer et al., 2022)

(Nair et al., 2020) (HireGo, 2018).

Blockchain technology offers decentralization,

immutability, and security, making it an ideal solution

for the car rental industry. This study aims to develop

a decentralized car rental system that enhances secu-

rity, transparency, and trust. To achieve this goal, we

deﬁne the following objectives:

• Build a decentralized car rental system allowing

direct peer to peer transactions

• Enhance security and trust between car owners

and customers using smart contracts.

• Reduce rental time and costs by automating agree-

ments and payments.

• Ensure privacy and data protection through

blockchain-based identity management.

• Improve overall transparency and reliability in car

rental transactions.

To address these objectives, our study explores the

following research questions:

• What are the essential requirements for building

decentralized car rental system that allows anyone

to rent out his unused cars?

• How can blockchain improve privacy and trust in

car rental systems?

• How can traditional contracts be replaced by

smart contracts on a distributed ledger?

• How can smart contracts ensure fair and secure

transactions between car owners and renters?

The remainder of this paper is organized as follows:

Section 2 presents a review of related works. Section

3 describes the proposed decentralized car rental sys-

tem, including its architecture, technologies, and im-

plementation. Section 4 details the experimentation

and testing procedures. Section 5 highlights the ma-

jor ﬁndings, and Section 6 concludes the paper with

future research directions.

2 REVIEW OF RELATED WORKS

Traditional car-sharing platforms rely on centralized

systems which are prone to data breaches and service

downtimes due to their single points of failure. In re-

cent years, the intersection of blockchain technology

with shared mobility has gained signiﬁcant traction,

Decentralized Car Rental System: Ensuring Security with Blockchain Smart Contracts

1111

addressing key challenges posed by traditional car-

sharing systems. Blockchain enables enhanced secu-

rity, transparency, and efﬁciency through decentral-

ized applications (DApps). In this section, we will

explore existing research on this topic. Our study is

categorized into centralized systems and blockchain

based applications to provide a comprehensive com-

parison of both approaches.

2.1 Centralized Systems

The process of renting a car is highly centralized,

where the car rental company being the main point

of contact for the driver to rent cars. Car rental com-

panies need to maintain a ﬂeet of cars, as well as car

stations and staff to efﬁciently run their operations,

which makes up for bulk of their operating costs. Car

rental companies cover these costs from (high) rental

rates charged to their customers.

• The SECREDAS (Doe et al., 2022) project de-

veloped a secure car-sharing system including an

embedded access device, a backend server, and a

mobile application. The system combines identity

management, secure authentication mechanisms,

and REST API security to mitigate threats such

as unauthorized access and API abuse. Secure

vehicle unlocking is accomplished by Bluetooth

Low Energy (BLE) and Near Field Communi-

cation (NFC) using a symmetric rent token (car

key).

• Ekar (ekar, 2021), launched in February 2016 in

Dubai, is a mobile application for car booking that

aims to simplify the car rental process. Compet-

ing with platforms like Uber and Careem, Ekar

allows users to conveniently rent vehicles on de-

mand via a smartphone application. The service

offers various beneﬁts, including free fuel, in-

surance, and parking, as well as the ﬂexibility

to choose a preferred car type and locate nearby

available vehicles. Users can rent a car instantly

and conclude their trip seamlessly. Despite its

convenience, the platform has been criticized for

trust and security concerns. It relies on a central-

ized platform for authentication, payments, and

ﬂeet management. Additionally, it requires a

highly skilled support team and multilingual cus-

tomer service to effectively manage operations.

• Sharik (sharik, 2021) Application Company for

Information Technology is a Saudi-based car-

sharing platform. It is the ﬁrst licensed electronic

rental broker approved by the General Transport

Authority, enabling individuals to rent out their

cars through mobile applications and websites.

The platform allows users to book nearby vehi-

cles on an hourly or daily basis. However, users

have reported trust, privacy and security concerns,

along with software-related issues. Additionally,

high rental costs have been a common complaint

based on user feedback.

• Shift inc (shiftinc, 2021) offers a fully automated

car rental experience, where a user’s smartphone

serves as the key for accessing vehicles. By in-

tegrating advanced technology, the platform en-

hances the efﬁciency, speed, and quality of the

rental process. Shift Inc combines hardware and

software solutions to provide better operational

oversight and maintain high service standards for

users. The platform also emphasizes competitive

pricing, aiming to maximize customer satisfac-

tion while minimizing resource usage. However,

Shift Inc operates as a centralized system, requir-

ing staff and intermediaries for management. De-

spite its automation, users have raised concerns

regarding trust and security within the platform.

2.2 Blockchain-Based Systems

In the car rental industry, blockchain operates sim-

ilarly to other blockchain transactions. Car owners

(or service providers) and clients registered on the

blockchain can sign digital smart contracts, which au-

tomatically enforce rental terms based on pre-deﬁned

rules, just like a traditional rental agreement.

• The study (Garc

ıa-Moreno et al., 2022) empha-

sizes the development of a decentralized car rental

application that uses blockchain technology to

eliminate intermediaries and allow car owners to

hire vehicles directly to clients without paying

commission fees. The researchers propose a de-

centralized application (DApp) that utilizes smart

contracts to facilitate peer-to-peer transactions se-

curely. They highlight the importance of using

Ethereum and tools like Ganache to create a re-

liable framework for these transactions. The doc-

ument mentions the use of smart contracts how-

ever the programming language and features are

not covered. In addition, by building the DApp on

the Ethereum network, the solution may be sub-

jected to Ethereum’s scalability issues, including

transaction speed and cost ﬂuctuations, especially

during high network congestion periods

• The work presented by (Kim et al., 2021) ﬁlls

the gap by introducing a decentralized model

where stations, acting as intermediaries, manage

a blockchain that maintains user anonymity while

securing transaction records. The proposed sys-

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tem undergoes a comprehensive security analy-

sis using BAN logic and AVISPA simulations,

demonstrating resilience against various attacks.

Overall, it advances the ﬁeld by ensuring mutual

authentication, protecting user privacy, and pro-

viding integrative solutions to security vulnera-

bilities identiﬁed in earlier research. This paper

presents a secure and decentralized car-sharing

system model and authentication scheme. The

system uses blockchain for data integrity and user

anonymity, addressing security vulnerabilities in

traditional systems. However, there is no real-

world implementation or system simulation. Ad-

ditionally, it requires high Communication Costs

due to the authentication process consisting of in-

teraction among three parties (users, vehicle own-

ers, and stations). This could affect scalability and

responsiveness during periods of high usage. De-

spite being decentralized, the system still issues

credentials and manages keys through a trust au-

thority. It does not explicitly mention the use of

smart contracts in the proposed decentralized car-

sharing system.

• The paper (Dwivedi et al., 2024) proposed

a decentralized vehicle rental system utilizing

blockchain technology to eliminate intermediaries

and commission fees typically associated with tra-

ditional car-sharing services. By implementing a

secure, transparent, and tamper-proof model, the

paper demonstrated how blockchain can enhance

user trust and system reliability in peer-to-peer ve-

hicle rentals.

• HireGo (HireGo, 2018) is a UK based company

that builds a decentralized car hire and car shar-

ing application. HireGo prioritizes security and

ease of use. Payments are made in advance

and assist the Ethereum chain‘s deposit contract.

The HireGo team is notiﬁed of the disagreement.

However, the user is unaware of the technical

complexity. This solution increases conﬁdence

and trust in the authenticity of the Identity-based

Blockchain user platform. In addition, this solu-

tion presents low cost. But, there is no documen-

tation available about this application, no infor-

mation about the programming techniques

• Volvero (volvero, 2022) proposes blockchain

technology to create a straightforward, reliable

and sustainable solution that connects vehicles’

owners with drivers. Also, Volvero provides full

insurance and customized protection to guaran-

tee the safety of Drivers and Owners who join

Volvero. Unlike other renting or sharing services,

there are no time or location restrictions. As a

security measure, Volvero creates smart contracts

at the start of the ride while a built-in insurance

covers drivers and all kinds of vehicles during the

whole period of sharing. Volvero’s patent tech-

nology tracks speed, acceleration, braking and

the car’s location. But, there is no information

about the programming techniques: blockchain

platform, wallet management, monitoring smart

contract...

2.3 Limits of Existing Works

Previous studies have identiﬁed various security

threats, including data integrity issues and poten-

tial attacks such as impersonation and man-in-the-

middle attacks. Some have proposed authentication

protocols; however, they often rely on centralized

structures that expose users to risks. For instance,

earlier efforts have explored hierarchical systems

and smart token-based access without fully leverag-

ing blockchain’s decentralized capabilities. Recent

works have explored blockchain-based car-sharing

as a decentralized alternative. Solutions such as

HireGo and Volvero utilize smart contracts to auto-

mate rental agreements, ensuring tamper-proof trans-

actions, identity veriﬁcation, and secure payments.

Unlike traditional systems, blockchain eliminates in-

termediaries, reducing fraud risks and operational

costs. However, blockchain solutions often face la-

tency issues, as seen in Ethereum-based smart con-

tracts, where transaction validation can take several

seconds, impacting user experience. To compare be-

tween existing works presented in the previous sec-

tion we deﬁned the following criteria: platform type,

cost, Security , Trust, smart contract usage. Table 1

compares existing works according to the predeﬁned

criteria.

According to the table 1, we found that centralized

solutions (eKar, Sharik, Shift Inc.) have lower secu-

rity and trust due to reliance on third parties. They

are more prone to security breaches and have higher

operational costs. Decentralized solutions (HireGo,

Volvero, blockchain-based research) use smart con-

tracts, improving transparency, security, and cost ef-

ﬁciency. However, some lack implementation details.

These solutions present some challenges in relation

to blockchain limitations include scalability, gas fees,

and communication costs in some implementations.

Furthermore, our analysis revealed that existing solu-

tions lack detailed information on the programming

methodologies used for implementation. None of the

reviewed works provide insights into the user experi-

ence (UX), such as interface design, ease of use, or

customer interaction with the system.

Decentralized Car Rental System: Ensuring Security with Blockchain Smart Contracts

1113

Table 1: Comparison of related Works.

Solution Platform

type

Security Trust SC Usage Key Limitations

(ekar, 2021) centralized low low No Requires third party intermediaries, security

concerns and high costs

(sharik, 2021) centralized low low No Security, trust, software related issues, high

rental costs

(shiftinc, 2021) centralized low low No trust security

(HireGo, 2018) decentralized high high yes No detailed documentation on programming

techniques

(volvero, 2022) decentralized high high Yes No information on blockchain platform, wal-

let management, and smart contract manage-

ment

(Garc

ıa-

Moreno et al.,

2022)

decentralized high high Yes Uses Ethereum; may suffer from high gas fees

and network congestion

(Dwivedi et al.,

2024)

decentralized high high Yes Transaction Costs (must pay transaction fees

in Ethereum),Testing Limitations,issues re-

lated to scalability on the Ethereum network

(Kim et al.,

2021)

decentralized high high Not ex-

plicitly

mentioned

Requires trust authority for credential man-

agement, high communication costs

3 CONTRIBUTION: CarChain

The proposed system is to implement a decentralized

application CarChain based on blockchain technol-

ogy allowing the owner or car rental ofﬁces to rent

cars in a safe, less cost and reliable way by using

smart contract which Highlights all relevant stages

including duration, pickup and payment. The con-

cept of blockchain in car rental industry works sim-

ilarly to any other blockchain transaction. Service

providers (or car owners) and end clients registered on

the blockchain can sign digital smart contracts which

execute agreement terms based on predeﬁned terms

and obligations. The smart contract is self-executable

computer code that lives on a blockchain platform.

When the conditions deﬁned in the smart contract are

met, the code executes itself without the need for an

intermediary (third party) to provide permission. The

smart contract is immutable and it allows the owner to

detect if the customer fulﬁlls the conditions described

in the smart contract in order to increase the mutual

trust. The smart contract also contains the necessary

information, such as information about the customer

(driving license proof, insurance) and rental data such

as car registration number, rate, mileage, duration of

rental, and credentials of the car owner. The ﬁnan-

cial transactions (rental payment) can be done by us-

ing associated cryptocurrency to get registered on the

blockchain. Figure 1 shows the proposed car rental

life cycle.

3.1 System Requirements

This section outlines the functional and non-

functional requirements necessary for the develop-

ment of the decentralized car rental system.

Functional Requirements

• User Management. The application allows users

(car owners or renters) to register and authenticate

securely.

• Create Digital Identity for Car. The application

allows the owner to create digital identity for car

like(type of car,car number,car insurance).

• Negotiate a Contract. Allows the owner to nego-

tiate a contract with the customer.

• Check Wallet Value. Allows the owner to check

wallet if the customer complete the payment or

not.

• Rate a Customer. Allows the owner to rate the

customer usage of his car.

• Search and Choose. Allows the customer to look

for cars depending on the availability or nearest

cars using the map and the appropriate car de-

pending on his preferences.

• Negotiate a Contract. Allows the customer to ne-

gotiate a contract with the owner. The customer

then can complete the rent process by agreeing on

contract and choose the way the car is delivered.

• Rate an owner: Allows the customer to rate the

car and the way that customer get it.

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Figure 1: CarChain rental life cycle.

• Select the Ways to Receive the Car. Allows the

customer to choose the way to receive the car by

Bar code and SMS or the customer can take the

key of car from the owner.

Non-Functional Requirements: explain the quality

aspects of the system to be constructed.

• Security and Privacy Requirements: The applica-

tion must provide integrity, veriﬁcation, and non-

repudiation of the reservation details and the abil-

ity to prove the validity of the data and the pos-

sibility to access it safely by the renter and the

owner only such as the time of reservation and

the type of vehicle. The identity of the consumer

and the car should be hidden to anyone except the

owner, the consumer and the car. (Madhusudan

et al., 2019)

• Conﬁdentiality of Booking Details: Only the

owner and consumer should have access to the in-

formation stored in booking details.

• System Scalability: The maintainability and scal-

ability of the system should be fully considered to

facilitate the follow-up work of the developer.

• Saving Time,Money and Effort: The way to cre-

ate a fast binding ﬁnancial agreement in the form

of a smart contract. Like traditional contracts,

smart contracts specify the obligations of both

parties, unlike traditional contracts,they program-

matically enforce them (Apriorit, 2023).

• Traceability and Reliability: In the proposed sys-

tem, the risk of fraud or damage will be mini-

mized. Data from various sources will be shared

on a blockchain network, enabling the execution

of different transactions, such as signing leasing

contracts, renting cars, and selecting insurance

plans. This creates the need for a single, reliable

source of truth for the stored data, ensuring that all

users have access to the same information. More-

over, the recorded data will be accurate, address-

ing both short-term and long-term needs. There-

fore, the system will require an immutable history

log of executed transactions and car-related data,

including information on damages, maintenance,

and repairs.(Auer et al., 2022).

• Usability and User Experience (UX): The appli-

cation will be user-friendly and ﬂexible, offering

all services in one place without the need for ad-

ditional programs. Every user can navigate the

application easily.

Sequence Diagram is an interaction diagram that

details how operations are carried out. It captures the

interaction between objects in the context of a collab-

oration. Figure 2, depicts the sequence diagram of

create car digital identity.

Figure 2: Sequence Diagram of Create car digital identity.

Figure 3, depicts the sequence diagram of negoti-

ate smart contract. This diagram shows the interac-

tions after authenticating each one of the owner and

customer.

Figure 3: Sequence Diagram of negotiate smart contract.

To represent the workﬂow of Carchain and entire

process, ﬂowchart diagram is used for designing, doc-

umenting and visualizing what is going on. The fol-

lowing ﬂowchart, ﬁgure 4, shows how actions or de-

Decentralized Car Rental System: Ensuring Security with Blockchain Smart Contracts

1115

Figure 4: CarChain Flowchart Diagram.

cisions ﬂow between the owner and the customer.

3.2 System Architecture

An architecture description is a formal description

and representation of a system, organized in a way

that supports reasoning about the structures and be-

haviors of the system. A system architecture can con-

sist of system components and the sub-systems devel-

oped, that will work together to implement the overall

system. The proposed CarChain decentralized appli-

cation is a hybrid architecture that combines the fea-

tures of on chain systems and off chain. This architec-

ture helps to reduce the cost and to improve the trust

and data protection.

1. OFF Chain. For Cross-Platform development

and Cost-Effective Solution, we use ﬂutter plat-

form with dart language to design and mange all

the front end interfaces. For, fast and Secure Data

Storage, we use Firebase as our system back end

off chain to collect, store and retrieve data.

2. ON Chain. We use (Metamask, Solidity, Bi-

nance smart chain) to check the balance in wallet,

make the payment, write the smart contract us-

ing solidity then deploy it on Binance chain. Bi-

nance Chain is chosen because of its high trans-

action throughput, low fees, and fast processing

capabilities, which are essential for a scalable and

efﬁcient car-sharing platform. Its seamless inte-

gration with the Binance Smart Chain (BSC) en-

ables rapid and cost-effective smart contract exe-

cution, making it an ideal solution for supporting

decentralized car-sharing applications. Addition-

ally, the robust security features of Binance Chain,

along with its large user base and liquidity, further

strengthen its suitability for ensuring smooth, se-

cure, and transparent car rental transactions.

Figure5 shows the System architecture.

The languages used are:

• Dart: is a client-optimized language for develop-

ing fast applications on any platform. Its goal is to

offer the most productive programming language

for multi-platform development, paired with a

ﬂexible execution runtime platform for applica-

tion frameworks (DartTeam, 2024).

• Solidity: is an object-oriented, high-level

language for implementing smart contracts.

Smart contracts are programs which govern

the behaviour of accounts within the Ethereum

state(SolidityTeam, 2024).

The Development Tools used are:

• Flutter. Flutter is a mobile application develop-

ment platform created by Google. It allows devel-

opers to create web, desktop, and cross-platform

applications that run on Android and iOS de-

vices. Flutter uses a reactive programming lan-

guage called Dart, making development faster and

easier than traditional methods(EduCBA, 2024).

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Figure 5: Carchain architecture.

• Firebase. Firebase is a development platform

known originally for its real time database that’s

still at its core a multi-node, key-value database

optimized for synchronizing data, often between

user machines or smartphones and centralized

storage in the cloud(VentureBeat, 2024).

• MetaMask. MetaMask provides an essential

utility for blockchain newcomers, token traders,

crypto gamers, and developers(MetaMask, 2024).

• Remix. Remix IDE allows developing, deploying

and administering smart contracts for Ethereum

blockchains. It can also be used as a learning plat-

form(Project, 2024).

• Trufﬂe Suite. The most comprehensive suite of

tools for smart contract development. It helps

to quickly build, test, debug, and deploy using

the trufﬂe Command line interface. Also to write

scripts and plugins in order to automate common

processes(Suite, 2024).

• Ganache. Ganache is a component of the Truf-

ﬂe Suite ecosystem that can be used to launch

an Ethereum blockchain. It provides a personal

Ethereum blockchain which you can use to run

tests, execute commands, and inspect state while

controlling how the chain operates(Suite, 2024).

3.3 Smart Contract Implementation

We developed a smart contract with solidity language

and we used remix as its editor. MetaMask is also

used to create a wallet for deploying the smart con-

tract.

Figure6 shows the Smart contract to be used in

CarChain application.

Figure 6: Solidity smart contract deﬁnition.

• contract: name of the contract

• Count: that is responsible for Id, and it is also

responsible for giving the number of cars in the

system.

• Struct car represents the car information such as:

id for the car , model, number, size car, car im-

age, also contains address wallet of the owner and

customer ... etc.

Decentralized Car Rental System: Ensuring Security with Blockchain Smart Contracts

1117

• Function createCar. this function will push a

new car to our map (allCar) by recording some

ﬁeld for example (model car , price , number car

, carImage ..etc), if something is missing from

the recorded data the car is not push to the map.

Figure8 shows the function createCar().

• Function rentCar: It is responsible for renting

the car to the customer. It requires to take the id

of the car and the period of rent days. Also, it

calculates the ﬁnal price of all the rent period and

pays the fees from the customer wallet. Figure8

shows the function rentCar().

Figure7 shows the car struct.

Figure 7: Car struct in solidity language.

4 EXPERIMENTATION AND

TESTING

This interface includes the car data that the owner will

display for rental, as follows: (car model, car number,

exact price, fuel, type). The owner must take a picture

of the vehicle and the insurance to be able to display

it within the application. Once all data is entered, it

is securely stored in Firebase and on the blockchain.

After clicking the Save button, a conﬁrmation mes-

sage appears, notifying the owner that their data have

been successfully saved.

Figure9 shows the car registration page.

Figure 9: Car registration page.

Account Screen. This interface displays the public

account address of the car owner and their connected

wallet. To use the platform, the owner must have a

preexisting wallet with sufﬁcient balance. The wallet

consists of:

• A private key, known only to the user, ensures se-

curity and conﬁdentiality.

• A public address key is used for blockchain trans-

actions and to verify ownership.

The public address key will be obtained as well as

the balance of wallet by entering private key by the

user. If he wants to change the address it is by using

the button (change account address). Figure10 shows

the account screen.

For choosing the way to receive the car we use

google map. We added our project in google cloud

platform in order to enable maps SDK and to get API

key for IOS and Android.

The smart contract is deployed on the Binance

Smart Chain (BSC). The BNB smart chain is known

by its fast transactions, reduced fees, and integra-

tion with the Binance ecosystem (Cryptomus, 2025).

Figure11 shows the smart contract and the corre-

sponding transaction. After conﬁrming rent, the

transaction details (transaction hash, sending address,

receiving address and the transaction fee) will appear

immediately on transaction details as shown in ﬁgure

12.

Figure 8: Function createcar()/rentCar().

BEST 2025 - Special Session on Blockchain and Enhanced Security for a New Era of Trust

1118

Figure 10: Account screen.

Figure 11: Contract deployed on BNB Smart Chain Net-

work.

Figure 12: Rent transaction details.

5 MAJOR FINDINGS

The security beneﬁts of using blockchain technology

for car rentals in the proposed decentralized applica-

tion are as follows:

1. Decentralization. The process is decentralized,

which eliminates the need for a third party or in-

termediary. This reduces the risk of fraud and ma-

nipulation since there’s no central authority that

can alter the contract terms or mishandle the trans-

action.

2. Immutability. Once a smart contract is deployed

on the blockchain, it cannot be altered. This im-

mutability ensures that the terms agreed upon by

both parties remain unchanged, increasing

trust between the car owner and the renter.

3. Automated Execution. Smart contracts auto-

matically execute when predeﬁned conditions are

met. This automation reduces the chances of hu-

man error and ensures that the rental terms (such

as payment, duration, and pick-up) are enforced

as agreed without the need for intervention.

4. Transparency. All transactions and contract de-

tails are recorded on the blockchain, providing

a transparent audit trail. This means all parties

can verify agreements and transactions, enhanc-

ing trust and accountability.

5. Security of Data. The use of smart contracts

involves storing sensitive information (like cus-

tomer veriﬁcation documents) in a secure man-

ner, often encrypted, that protects against unau-

thorized access and data breaches.

6. Digital Integrity. The veriﬁcation of transactions

through consensus mechanisms ensures that only

legitimate transactions are recorded, reducing the

risk of fraud or double spending.

7. Fast and Less Expensive. Binance Chain is cho-

sen because of its high transaction throughput,

low fees, and fast processing capabilities (Cryp-

tomus, 2025), which are essential for a scalable

and efﬁcient car-sharing platform.

These features make the car rental process more

secure and trustworthy for both car owners and renters

by minimizing risks typically associated with tradi-

tional rental systems, which often involve centralized

control and numerous intermediaries.

6 CONCLUSIONS

The CarChain system is a decentralized application

developed using Dart and Solidity. The CarChain sys-

tem offers cars from owner to the customer for rent in

peer to peer model. It addresses the problems of tra-

ditional car rental systems which are centralized and

require a third party or a middleman who adminis-

trates all the rental process between the owners of cars

and customers. Additionally, a smart contract is used

to automatically create rental cars. It saves time and

money for the consumer and makes renting a car eas-

ier and safer for both the owner and the renter. This

work can be improved by integrating Service Level

Agreements (SLAs) with smart contracts to ensure

Quality of Service (QoS). As highlighted in the sur-

vey paper (Hamdi et al., 2022), SLAs deﬁne and guar-

antee the required service levels. Furthermore, the

Decentralized Car Rental System: Ensuring Security with Blockchain Smart Contracts

1119

study (Abdelhamid et al., 2024) highlights the bene-

ﬁts of utilizing Artiﬁcial Intelligence (AI) techniques

to improve blockchain-based solutions. These tech-

niques can be used to optimize the selection process

for the most suitable car.

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