Sina Ahmadi
email: sina0@acm.org

Challenges and Solutions in Network Security for Serverless Computing

Keywords: Serverless Computing, Network Security, Cloud Security, Data Privacy Issues, Insecure Dependencies I

This research study explores the challenges and solutions related to serverless computing so that the computer systems connected to the network can be protected. Serverless computing can be defined as a method of managing computer services without the need to have fixed servers. The qualitative research method is used by this research study, which does not include any numerical data and involves the examination of non-number data so that the network security challenges can be identified in detail. In the literature review, the past studies from 2019 to 2023 are reviewed to identify study gaps so that the foundation for investigating serverless network security. The literature review is based on thematic analysis, so all the data can be organized into meaningful themes. The findings of this research study include the solutions to the challenges like data privacy, insecure dependencies and limited control. The strategies to overcome these challenges include encryption, strong monitoring and other relevant strategies. This research study also suggests the use of blockchain technology and Artificial Intelligence. In short, this research study provides insights to improve serverless computing security and also guides future researchers to innovate creative solutions for developing security challenges.

INTRODUCTION

Serverless computing can be defined as the approach to providing backend services on an as-used basis. Serverless does not mean servers are not used; they are used, but the organizations getting serverless computing services are charged based on the services they use [START_REF] Javed | Serverless platforms on edge: a performance analysis[END_REF]. This means the amount or the number of servers still needs to be fixed. Serverless computing comes with several benefits and differs from traditional cloud computing. For instance, it offers great scalability, enhanced processing time, more flexibility, reduced cost and quicker time to release. It is important to consider that server computing not only comes with benefits but also significant challenges that need to be overcome by organizations to enjoy its advantages. The major challenges are related to the network's security, which includes the security of the connected devices and users and the data getting transferred from one device to another. This research study aims to explain the challenges related to network security for serverless computing along with their solutions. The best way to overcome such challenges is to limit access to the network to protect it from unauthorized access. Moreover, security systems must be implemented, such as a two-factor authentication method, so that no unauthorized person or device could harm a specific network's personal and sensitive information.

II. PROBLEM DEFINITION

Serverless computing is the main part of the cloud server. Its reliability and lower cost make it suitable and useful for large projects. However, they have to face many challenges, especially regarding network security [START_REF] Gadepalli | Challenges and opportunities for efficient serverless computing at the edge[END_REF]. They can solve this problem to reduce their challenges.

A. Limited Visibility and Control

In serverless computing, there is always a challenge which they have to face. The challenge is the loss of control and limited visibility [START_REF] Kumar | Serverless architectures review, future trend and the solutions to open problems[END_REF]. In traditional security approaches, the administrators have direct access to the system, but this needs to be updated in serverless computing. The lack of insight into these areas and the absence of traditional networking controls give the unauthorized user a chance to get access to the system or data. These challenges can be solved by monitoring the system and increasing its security. Without strong visibility over the network, an organization can face a lot of challenges in detecting and responding to security incidents.

B. Insecure Dependencies

Serverless applications depend on third-party libraries like APIs, leading them to face different security threats [START_REF] Yussupov | Facing the unplanned migration of serverless applications: A study on portability problems, solutions, and dead ends[END_REF]. This dependency creates a path for hackers or other unauthorized users to access the network or data. Organizations should understand how to control this to secure the network and data. Effective measures should be created to monitor and update the third-party libraries. When the organization starts to reduce these challenges, it can help the system remain protected from external illegal access.

C. Cold Start Attacks

There is another challenge for serverless computing named "cold start", characterized by early functions that have not been executed recently [START_REF] Golec | Cold start latency in serverless computing: A systematic review, taxonomy, and future directions[END_REF]. This temporary delay creates a window for the attackers to gain access to data, which raises security concerns. Currently, traditional security measures cannot be proven effective, highlighting the importance of new solutions. To reduce the effect of this challenge, they need to create new strategies to reduce the cold start time without compromising security. These risks can be reduced by implementing security measures on serverless applications. As the organization overcomes these challenges, the solutions to reduce the external access during the cold start phase ensure the increase of reliability of the serverless computing system.

D. Data Privacy and Resilience

Adding data processing in serverless computing increases the chances of damaging the data privacy and reliability of the system [START_REF] Singh | Privacy-preserving serverless computing using federated learning for smart grids[END_REF]. Organizations may hesitate to share sensitive data due to these data privacy issues in serverless systems. The danger of data loss or corruption comes as a challenge to the reliance on the serverless system. To solve this issue, they require a nuanced approach to data management, strong encryption, security measures and effective backup strategies. Ensuring a good balance between data privacy and the advantages of serverless computing becomes important for the organization.

E. Injection Attacks and Isolation

Serverless functions sharing a limited run time system cause isolation challenges like injection attacks [START_REF] Xiong | Warmonger: inflicting denial-of-service via serverless functions in the cloud[END_REF]. These challenges can cause an attacker to gain a golden chance to have unauthorized access. This highlights that the organisation must apply a strong run time protection mechanism and good isolation strategy. The main difficulty comes in making the system strong from different attacks while maintaining efficiency in a serverless structure. The organization must apply strong security measures to detect attackers early, ensuring the system's integrity during the shared run time environment. As the system progresses, solving these challenges to create a safe and reliable system becomes important.

F. Resource Exhaustion and Denial-of-Service (DoS)

The scaling of resources in serverless computing environments leads to increased challenges related to resource exhaustion and the threat of denial-of-service attacks [START_REF] Kelly | Denial of wallet-defining a looming threat to serverless computing[END_REF]. The harmful hacker may try to overpower or control the serverless system, which causes bad performance or unavailability of services. They must apply proactive measures to solve these challenges, including effective rate limiting and planned utilization of auto-scaling features. By improving how resources are assigned and increasing responsiveness, an organization can save their serverless system against unauthorized access, ensuring strong performance even when there are malicious attempts by attackers to take advantage of this dynamic scaling serverless computing model.

III. LITERATURE REVIEW

A. Introduction to Serverless Computing

Serverless computing mainly relates to providing backend services based on 'as-used.' This means the servers are still used, but a firm that avails backend services from a serverless provider is charged based on usage instead of a specific number of servers or bandwidth. [START_REF] Cassel | Serverless computing for Internet of Things: A systematic literature review[END_REF] researched serverless computing in the case of the Internet of Things. The research showed that with the help of serverless computing, solutions can operate in an integrated manner on cloud, fog, and edge layers. Besides, many critical functions can be performed on fog and edge to gain benefits from low-latency responses. On the other hand, heavy functions can be performed on the cloud to process large amounts of data created by IoT sensors.

[14] also focused on serverless computing and its adoption. The researchers stated that serverless computing is becoming famous because of its management simplicity and lightweight-ness. It attains these merits by lessening the granularity of the computing unit. Particularly, serverless computing enables users to emphasize the function instead of other scheduling or management problems faced by the platform provider. The researchers mainly conducted a detailed survey on serverless computing, focusing on its infrastructure features. It was also seen that serverless computing is expected to dominate future cloud platforms.

B. Security Challenges in Serverless Computing

Serverless computing encounters many security issues and challenges. One major issue is the occurrence of cold-start attacks. In serverless computing, idle resources are usually released in case of favourable pricing policy and energy efficiency. This procedure is called scaling to zero. When the resources are scaled to zero, it takes some time to be processed further for usage when a new function comes. This latency is thus known as a cold start. [START_REF] Solaiman | Novel architecture for mitigating cold start problem in serverless computing[END_REF] focused on this issue and conducted research to mitigate it. The researchers stated that the cold start relates to the time delay between attaining a lambda request in the application and the initiation of executing code for it. AWS is one of the famous serverless service providers and has developed Snap Start to resolve the issue of cold start attacks.

Another area for improvement with serverless computing is inadequate authorization and authentication. In this case, the user does not have direct control over their visibility over the infrastructure and servers and has to depend on the cloud provider to protect and secure the code and data. [START_REF] Li | Securing Serverless Computing: Challenges, Solutions, and Opportunities[END_REF] also researched this issue and stated that serverless computing features, like fragmented application boundaries, have led to security issues. Different serverless platforms also adopt different security measures to improve the serverless environment. Thus, the researchers analyzed the literature in detail and conducted a gap analysis based on industrial solutions regarding serverless computing.

A major issue with serverless computing is data at rest and transit. Data at rest relates to when data is stored in one place instead of moved to another place (in transit) or loaded into memory to be utilized by a software program. This feature of serverless computing faces many issues. [START_REF] Kumari | Data Controlling and Security Issues in Cloud: A Step Towards Serverless[END_REF] also focused on such issues with data at rest. It can encounter the issue of ransomware, a kind of malware that encrypts the data at rest. This makes the data unusable by anyone. Besides, it is also susceptible to data breaches by malicious attackers who can access and leak the data. Another issue is linked to excessive or unauthorized access to data at rest. All these issues enhance the security threats to serverless computing. Shared resources and multi-tenancy also lead to security issues in serverless computing. A multi-tenant serverless platform mainly allows various tenants or users to utilize the same resources. Each user has access to their resources without interfering with others. [START_REF] Stojkovic | MXFaaS: Resource Sharing in Serverless Environments for Parallelism and Efficiency[END_REF] also focused on the aspect of resource sharing in serverless computing. Multitenancy is a major threat of hacking. No matter how safe or secure an encryption is, it can be hacked with the right information. Thus, The researchers proposed a new serverless computing platform, MXFaaS, which is secure and has improved efficiency levels.

Another major issue with serverless computing is dependency security. The aspect of third-party dependencies in serverless computing raises security concerns. [START_REF] Marin | Serverless computing: a security perspective[END_REF] conducted research on this security problem. The researchers stated that the issue of third-party dependency is increased in serverless platforms because of the complexity that occurs in deploying cloud services based on users' demands. Serverless computing demands a dynamic allocation of different computer resources. The researchers stated that there are many shortcomings of serverless platforms, and there is a need for proper security solutions to such issues. To overcome the security issues that occur in serverless computing, there is a need to implement proper mitigation measures. The issue of cold-start attacks can be mitigated with the help of full memory encryption and disabling sleep capabilities. [START_REF] Kumari | ACPM: adaptive container provisioning model to mitigate serverless cold-start[END_REF] also focused on mitigating this issue. Encrypting RAM helps reduce the possibility of an intruder being able to attain the encryption keys or any other data from the memory through a cold boot attack. This technique mainly requires hardware, applications, or operating system changes. Besides, the computer system will never go into sleep mode if one turns off sleep capabilities. This will help prevent cold boot attacks.

C. Solutions to Security Challenges

The issue of authorization and authentication in serverless computing can be resolved by implementing IAM (Identity and Access Management) and Least Privilege Principle. [START_REF] Wu | Game to dethrone: The least privilege CTF[END_REF] also conducted research in this regard. According to the researchers, this principle mainly allows users to execute or read only the necessary resources and files. In this case, time-limited privileges can also be implemented to ensure that users can access sensitive information only for a limited time. The overall benefit is that serverless computing easily mitigates and prevents security issues.

Data security issues in serverless computing can also be mitigated by implementing encryption practices. [START_REF] Arulprakash | Improved Encryption Towards Data Security in Serverless Computing[END_REF] researched improving encryption in data security in serverless computing. The researchers found that serverless computing is becoming common because of its rapid adoption by tenants and cloud providers due to its flexibility, elasticity, and scalability. However, it encounters security issues and needs proper encryption measures. The researchers developed an efficient and secure access control system for serverless security computing for resource and knowledge sharing with the help of attribute-based encryption. The security analysis revealed that the method proposed by the researchers successfully improved data security in serverless computing.

Implementing proper multi tenancy security measures like resource allocation and segregation strategies is also important. The multi-tenant security model is very crucial in this regard. [START_REF] Prakash | Cloud serverless security and services: a survey[END_REF] conducted research on this concept. This model helps firms in protecting their cloud architecture. Properly maintaining and optimising this model is very important; otherwise, it can lead to potential security risks. Multi-tenancy can be of different degrees, such as high, middle, and low. It can provide many benefits to the users, such as effective resource usage, easier deployment and optimized bills. Using real-time monitoring tools and anomaly detection can also help improve monitoring solutions. CSPM (Cloud Security Posture Management) plays a very important role in improving the security of serverless platforms. It mainly relates to a set of practices, technologies, and tools developed to enhance, manage, and assess the security posture of cloud platforms. According to [START_REF] Enriquez | Cloud Security Posture Management/CSPM) in Azure[END_REF], CSPM helps companies address and identify security problems, vulnerabilities, and misconfigurations that can expose their technological infrastructure to probable threats. CSPM also offers consistent automated remediation and monitoring to manage a strong security stance in cloud environments. Moreover, it also helps firms in governance and compliance, risk assessment and identification, real-time monitoring, cost optimization, and automated remediation.

D. Serverless Security Tools and Technologies

Serverless security demands a shift in how companies focus on application security. Rather than developing security around the application, companies should additionally develop security around different functions within the application, which third-party providers provide. According to [START_REF] O'meara | Serverless computing security: Protecting application logic[END_REF], this extra layer of security helps ensure the least privileged access control and proper application hardening so that every single function does exactly what it is supposed to do. This helps companies maintain compliance and improve their security posture. The researchers stated that Amazon was the first to develop a serverless platform named Lambda in 2014. Today, many other firms offer much more secure serverless computing services. [31] also conducted research in this regard. They found that the serverless platforms can be a circumscriptive topic, but it is a complex and vast subject. The research focused on different security aspects within the cloud, mobile, and its applications. Serverless computing has improved security measures since it is stateless and ephemeral. Different serverless functions, such as AWS Lambda, operate for a short time and then die. Since they have no memory, long-term security attacks are not risky. Therefore, the overall security of such systems can be improved easily.

IV. METHODOLOGY/APPROACH

A. Research Design

• Qualitative Approach A qualitative research method has been chosen to conduct this research study. It can be defined as a method that includes collecting and analysing non-numerical data to extract important and accurate information. This methodology is chosen to explore the network security challenges within serverless computing environments in detail. With the help of this methodology, this research study can explore the depth of contextual information, which provides a holistic understanding of multiple issues related to serverless network security.

• Literature Review as Foundation

Literature review plays a significant role in this research study, which explains the role of different past studies from 2019 to 2023. For this purpose, several scholarly articles and publications have been explored based on themes, and the thematic analysis method was used to conduct the literature review. The purpose of conducting a literature review is to identify the gaps in the research that are helpful for future research studies. Moreover, this process also helps the research design to gain a strong footing, which ensures a thorough and well-informed investigation into the challenges and solutions in network security for serverless computing.

B. Data Collection Methods

• Comprehensive Literature Review

The comprehensive literature review plays a significant role in collecting data for this research study, including the exhaustive and systematic search for relevant scholarly publications and articles. It also involves the analysis of databases like ScienceDirect, ACM Digital Library, and IEEE Xplore; all of these are up-to-date and high-quality sources to get accurate information. The criteria to find the data are relevance to network security challenges in serverless computing, the credibility of the source, and recent publication dates. Moreover, keywords like solutions, challenges, network security, serverless computing, etc., are used to ensure thorough and targeted exploration of the existing knowledge.

C. Data Analysis Technique

• Thematic Analysis

A literature review based on thematic analysis has been conducted to collect data for this research study's authentication. It is considered one of the most significant data analysis techniques, which provides an insightful and structured approach for uncovering patterns within the collected data. It can be stated that thematic analysis is the best for identifying, analysing and reporting important themes relevant to network security challenges and solutions in serverless computing. The data is organized in meaningful themes so that the complex issues can be addressed effectively. This approach goes far beyond data summarization because it provides deep insights into the research questions by highlighting important patterns and relationships.

• Theme Identification Process

Identifying themes in the literature review is also an important step to be considered, as it involves organising the collected data into meaningful and appropriate themes. For this purpose, the research objectives are considered, and the themes are created based on these objectives related to network security challenges in serverless computing. Accuracy has been ensured by organizing all the gathered data under these significant themes and documenting all the details and findings of each research study to maintain transparency.

• Results and Discussion

Studying how to keep serverless computing secure and safe in cloud servers has expressed a lot about the difficulties and its solutions in network marketing. The security challenges recognized include limited visibility, insecure dependencies, cold start attacks, data privacy issues and resource exhaustion. These challenges have encouraged the employment of targeted solutions. • Limited Visibility and Control

The logging mechanism and strict monitoring have proven effective in response to the limited visibility and control. Implementing cloud-native monitoring tools during the implementation phase has improved the ability to observe serverless computing behaviour [START_REF] Venugopal | Serverless through cloud-native architecture[END_REF]. In addition, adding real-time data on the execution of the functions, network interaction and resource usage helps to solve the challenge of limited control. This type of outcome gives power to the organization to properly detect and respond to security incidents and ensures a high level of awareness in the serverless system. Moreover, a successful approach strengthens the security protocols and generates a strong foundation for more informed and effective of serverless computing systems. It also highlights this cloud-based system's crucial need for visibility and control.

• Insecure Dependencies

To solve the challenges of insecure dependencies, the strategy includes regular audits, static code analysis for thirdparty libraries and updates. Proactive approaches have been proven to reduce weaknesses and secure serverless systems effectively. By carefully monitoring and updating the dependencies from time to time, the organization reduces the number of points where attackers can attack and gain access to sensitive data. This results in more serverless components, reducing the risks of unauthorized access and data loss. This implementation success highlights the importance of a proactive approach and the need for continuous monitoring and management from any external dependencies to secure serverless computing from other harmful access or attackers.

• Cold Start Attacks

Continuously facing weaknesses are caused by cold start attackers in the serverless system. It can be stopped by making a serverless system more efficient. Adopting strategies like function warm-up mechanisms and strategic placement has proven very successful [START_REF] Li | The serverless computing survey: A technical primer for design architecture[END_REF]. Organizations have minimized the vulnerability during the initial phase, directly enhancing the serverless computing system's security and overall performance. Function warm-up mechanisms include periodically activating the function, ensuring that they are in the warm-up phase and they are ready for rapid execution, which reduces the delays during a cold start. In strategic placement, functions should be distributed in serverless architecture, while factors like anticipated demand and resource allocation should be considered. If these techniques are successful, they will not only increase the security of the system from attackers but also make the most efficient and responsive serverless computing system.

• Data Privacy and Resilience

Encryption measures have always proven to be effective when applied to data. Encryption plays an important role in securing data integrity [START_REF] Seth | Integrating encryption techniques for secure data storage in the cloud[END_REF]. It makes it unreadable by unauthorized users and secure during transmission. This not only helps in compliance requirements but also injects confidence in the organization and the user about the security of their sensitive information. These successful encryption measures create a reliable defence, adjusting the serverless computing system in the best practice of data security and increasing the overall trust in data security in serverless computing systems.

Figure 12: Data Privacy in Serverless Architecture [START_REF] Addeppally | Serverless Architecture -The What, When and Why[END_REF] • Injection Vulnerabilities

The successful injecting vulnerabilities include a proactive run time mechanism, especially Web Application Firewalls (WAFs). This strategy has proven highly effective in reducing the risks of injection attacks [START_REF] Aslan | A comprehensive review of cyber security vulnerabilities, threats, attacks, and solutions[END_REF]. The WAFs operate by detecting and blocking the injection attacks; therefore, the security of the serverless environment remains balanced. This step results as an important defence against unauthorized access and data unreliability, which could result from malicious injection attempts. By adding WAFs to the serverless system, the organization increases its overall security, ensuring the reliability and integrity of data.

• Resource Exhaustion and Denial-of-Service (DoS)

The charging of serverless systems based on the number of resources being consumed results in facing the challenge of resource exhaustion attacks. The attackers may try to overpower the system by triggering many functions like this, which results in Denial of service and rising costs. The strategic solution is to implement such measures to stop the threats. Applying rate-limiting mechanisms helps in controlling the frequency of function; on the other hand, continuous monitoring shows unusual spikes in the system activity. Implementing billing alerts results in an early warning to the system, which enables a rapid response to potential attacks on the system. In addition, by applying automated scaling policies, it adjusts the resources according to their demand, enhancing the system's overall reliability against resource exhaustion attacks by the attackers. By implementing these steps, the organization can strengthen its serverless system, ensuring efficient resource consumption, effective cost control, and protection against dangerous attempts to take advantage of the platform.

• Vendor Lock-in Risks

Using serverless computing generally ties an organization to the specific cloud service providers, which raises concerns about vendor lock-in [START_REF] Harauzek | Cloud Computing: Challenges of cloud computing from business users perspective-vendor lock-in[END_REF]. The complications of sharing serverless applications between different providers result in the creation of challenges, including the maintenance of consistent security protocols across the cloud system. To solve these challenges, the organization must adopt a multi-cloud strategy where feasible to reduce the risks related to vendor lock-in. This allows the organization to vary its cloud service providers, decreasing dependency on a single vendor and providing flexibility in managing resources. In addition, adopting open standards and confirming the portability of serverless applications can result in a smoother transition between cloud providers. By adopting a multicloud approach and prioritizing interoperability, the organizations not only enhance their monitoring flexibility but also decrease their potential challenges and the risks which are related to being bound with only a single cloud service provider in the evolving system of the serverless environment.

V. CONCLUSION

To conclude, this research study has highlighted the methods and strategies used to make computer systems safer, especially when connected to a serverless computing network. It explored the challenges and innovative solutions by focusing on the studies conducted by past researchers related to serverless network security. According to this research study, encryption and strong monitoring are important to overcome such challenges as insecure dependencies and limited control over data and devices connected with the network. Moreover, it highlighted the importance of advanced technologies like AI and blockchain technology so that emerging challenges could be overcome with smart and advanced technologies. All these technologies are helpful in staying alert of upcoming threats in real time. The findings of this research study provide a basis for future researchers to focus on developing innovative strategies so that serverless computing systems can be kept secure and protected.

VI. FUTURE SCOPE

This study provides scope for future researchers to focus on significant factors that could enhance their study regarding challenges and solutions in network security for serverless computing. For instance, they can focus on integrating advanced technologies such as blockchain technology and Artificial Intelligence to explain the security of serverless computing. Future researchers can explore how these emerging technologies can complement existing security measures so that innovative solutions can be developed for the purpose of addressing emerging threats and enhancing serverless systems as a whole.

As modern organizations are moving towards using multi-cloud strategies, it is important to explore security considerations across different cloud providers. This research study enables future researchers to focus on developing advanced mitigating security approaches so that such challenges can be resolved within diverse cloud environments. This will lead to protecting data as well as the applications within the network.

Future studies need to focus on the identification of advanced threats related to security in serverless computing. They must explore new attack vectors and innovative applications that can be used for data breaching and data theft. Moreover, they must also focus on real-time threat intelligence and adaptive security measures that play an important role in helping organizations overcome potential risks in the world of ever-evolving cybersecurity.

Figure 1 :

 1 Figure 1: Serverless Computing [2]

Figure 2 :

 2 Figure 2: Serverless computing architecture in cloud network[START_REF] Basumallick | What Is Serverless? Definition, Architecture, Examples, and Applications[END_REF]

Figure 3 :

 3 Figure 3: Serverless Security in Cloud Network [9]

Figure 4 :

 4 Figure 4: Denial-of-service (DoS) attack[START_REF] Cloudflare | What is a denial-of-service (DoS) attack?[END_REF]

Figure 5 :

 5 Figure 5: Introduction to Serverless Computing[START_REF] Fortinet | What Is Serverless Computing?[END_REF]

Figure 6 :

 6 Figure 6: Threats in Serverless Computing[START_REF] Kolodiy | Importance of Security in Serverless Technologies[END_REF]

Figure 7 :

 7 Figure 7: Solutions to Security Challenges in Serverless Computing[START_REF] Sharma | Serverless Computing: Advantages and Disadvantages[END_REF]

Figure 8 :

 8 Figure 8: Single-Tenant vs Multi-Tenant [27]

Figure 9 :

 9 Figure9: Serverless Security Practices[START_REF] Casey | Serverless Security Best Practices[END_REF]

Figure 10 :

 10 Figure 10: Serverless Security Using the Shared Model[START_REF] Center | Serverless Security: Everything You Need to Know About It[END_REF]

Figure 11 :

 11 Figure 11: Pros and Cons of Serverless Computing[START_REF] Adastracorp | The Pros and Cons of Serverless Computing[END_REF]


Sina Ahmadi
email: sina0@acm.org.

Zero Trust Architecture in Cloud Networks: Application, challenges and future opportunities

Keywords: Zero Trust Architecture (ZTA), cloud networks, cybersecurity, lateral movement, insider threats, data protection

Cloud computing has become essential in this digital world as it provides opportunities and challenges for organizations. This research explores the implementation and effectiveness of Zero Trust Architecture (ZTA) in addressing security challenges within cloud networks. Utilizing qualitative research methods, including a systematic literature review from 2020 to 2024, the study investigates insights from diverse sources such as journal articles, academic literature, and case studies. Thematic analysis organizes findings into critical themes, revealing ZTA's impact on mitigating lateral movement, reducing insider threat probability, enhancing network micro-segmentation, and improving identity and access management. The comparative analysis demonstrates significant improvements in security incidents post-ZTA implementation. Moreover, the study highlights best practices for ZTA adoption and outlines future advancements, including integration with emerging technologies like machine learning and artificial intelligence. This research underscores ZTA's pivotal role in fortifying cloud network security and offers valuable insights for practitioners and researchers.

INTRODUCTION

Cloud networking is now the backbone of digital infrastructure, which reshapes the system of data storage, processing, and accessibility for organizations [START_REF] Ghani | Issues and challenges in cloud storage architecture: a survey[END_REF]. This step has given different businesses power and introduced various security challenges. Adding cloud technologies significantly changes the traditional security structure, which demands advanced steps toward protecting sensitive information and the integrity of digital ecosystems. In the cloud networking system, decreasing data storage and processing defects present a significant challenge [START_REF] Sadeeq | IoT and Cloud computing issues, challenges and opportunities: A review[END_REF]. Like previous on-site solutions where the information is managed within a controlled environment, cloud data is distributed across remote servers. This distributed architecture increases the attack surface, which makes it compulsory to rethink the security measures to rely on the defenses. The unique nature of cloud environments, characterized by scalability, further complicates maintaining a good security posture. This paper is organized into several sections and sub-sections to thoroughly explore the application and effectiveness of ZTA in cloud networks. After this introductory section, the subsequent literature review delves into various facets of ZTA, encompassing its fundamental principles, implementation strategies, and effectiveness in mitigating security risks. Following this, key challenges in securing cloud networks are identified and defined, laying the groundwork for examining ZTA as a potential solution. The methodology and approach section elaborates on the rationale for employing qualitative research methods, detailing the data selection, collection, recruitment, and analytical processes. It underscores the importance of conducting a systematic literature review to gather insights from relevant sources and organize thematically for comprehensive analysis. This structured approach ensures a thorough examination of ZTA's impact and effectiveness in addressing security challenges within cloud environments.

LITERATURE REVIEW

Introduction to Zero Trust Architecture (ZTA) in Cloud Networks

Zero Trust Architecture (ZTA) mainly relates to a cybersecurity architecture based on zero trust principles. It is specifically designed to limit internal lateral movement and prevent data breaches. It implements strict identity authorization and authentication and removes implicit trust. The ZTA is based on seven principles, i.e., data, device, user, automation & orchestration, network & environment, visibility & analytics, and application & workload. [START_REF] Fernandez | A critical analysis of Zero Trust Architecture (ZTA)[END_REF] also conducted a critical analysis of ZTA. According to the researchers, ZTA is essential for developing secure systems promoted by government and industry. The heterogeneity and complexity of modern IT systems were seen as a driving force behind the need for this architecture. A study was also conducted by [START_REF] Stafford | Zero trust architecture[END_REF] in this regard. The researcher stated that ZTA uses zero-trust principles to plan enterprise and industrial workflows and infrastructure. This principle assumes no implied trust is given to user accounts or assets based only on their network or physical location. Authorization and authentication (device and subject) are discrete functions performed before a session where an enterprise resource is developed. Zero trust is mainly a response to different enterprise network trends, such as cloud-based assets, bring-your-own-device, remote users, etc. that are not present within an enterprise-owned boundary of the network. Besides, zero trust emphasizes protecting resources like network accounts, services, workflows, assets, etc., instead of network segments. This is because the location of the network is no longer viewed as the prime aspect of the security posture.

Fundamental Principles of Zero Trust Architecture

ZTA is based on different fundamental principles. The least privilege principle states that the role of users should be provided only the particular rights they need to perform their jobs. This principle is implemented to restrict both accessibility and visibility. The concept of this principle is straightforward. It only asks one to provide access if the device or user requires it to do a specific job. Otherwise, there is no need to provide access. [START_REF] Syed | Zero trust architecture (zta): A comprehensive survey[END_REF] also conducted research in this regard. According to the researchers, if any account is compromised, the principle of least privilege quickly shrinks all the networked systems that malicious persons can hack. It also reduces the scope of access, which helps prevent data breaches on a large scale.

Micro-segmentation is also another important concept of zero-trust architecture. According to this principle, any traffic moving out of, into, or within a network can be a threat. It helps in isolating such threats before they spread. This helps in preventing the lateral movement of the threats. [START_REF] Xie | A micro-segmentation protection scheme based on zero trust architecture[END_REF] conducted research on this principle and its working. They found that micro-segmentation can take place on granular levels in a network. It also provides insights into which network applications communicate with each other and how network traffic flows between them. This is mainly termed as application layer visibility. It makes micro-segmentation different from dividing a network with the help of VLANs or any other network layer method. Figure 2 shows Zero Trust micro-segmentation.

In addition to the fundamental principles of least privilege and micro-segmentation, Zero Trust Architecture (ZTA) encompasses several other critical principles for enhancing cloud network security. Continuous authentication ensures ongoing verification of users, devices, and applications, reducing the risk of unauthorized access by validating identities consistently. Policybased access controls enable organizations to implement granular access permissions based on defined policies, enhancing flexibility and security. ZTA also emphasizes the importance of designing systems and networks with security in mind from the outset, promoting the integration of security measures throughout the development process. Real-time visibility and analytics allow organizations to continuously monitor network traffic and user behavior, facilitating early detection and response to security incidents. Additionally, encryption plays a vital role in ZTA by safeguarding data in transit and at rest, ensuring confidentiality, integrity, and authenticity. Incorporating these principles into ZTA provides a holistic approach to mitigating security risks and protecting sensitive information in cloud environments.

Fig. 2. Zero-trust Micro-segmentation [8]

Multi-factor authentication (MFA) is another critical component of ZTA. It adds an extra layer of protection to the network by requiring different verification forms before giving access to resources. In zero trust architecture, the aspect of trust is never assumed. It treats each access request as coming from an untrusted network. [START_REF] Khan | Zero trust architecture: Redefining network security paradigms in the digital age[END_REF] also researched this principle. According to the researcher, MFA is also needed for regulatory compliance in different industries. Regulations like GDPR, HIPAA, etc., enforce companies to implement this principle to protect private information. It involves using factors such as PIN or password, biometric verification, facial recognition, etc., which helps gain a high level of assurance regarding the user's identity.

Implementing Zero Trust in Cloud Network Infrastructure

Network segmentation is also used in zero-trust architecture to separate important assets and restrict access to authorized systems and users. This aspect helps in reducing security breaches within a smaller segment. This makes it easy to respond to or detect any security incidents. According to [START_REF] Tyler | Trust no one? a framework for assisting healthcare organisations in transitioning to a zero-trust network architecture[END_REF], network segmentation in ZTA provides many benefits. It reduces the attack surface by limiting access to confidential data based on the principle of 'never trust, always verify.' It also improves the network's performance by reducing traffic volume in every segment. This also results in fast response time and low latency. Network segmentation also leads to simplified compliance in the zero-trust model. Data protection is critical in cloud environments. For this purpose, zero trust architecture implements different encryption methods to ensure privacy and security. [START_REF] Chen | A security awareness and protection system for 5G smart healthcare based on zero-trust architecture[END_REF] also conducted research in this regard. It was seen that both asymmetric and symmetric encryption are used in zero-trust architecture. Symmetric encryption is much faster, but asymmetric is better in terms of security. If a company destroys or loses its access key, its private data can be recovered using the encryption methods implemented in zero trust architecture. Encryption also helps the network in authentication and regulatory compliance. Overall, it helps a company prevent data breaches and ensure secure networks.

Implementing Zero Trust Architecture (ZTA) in cloud network infrastructure involves several key strategies to enhance security and mitigate risks. One crucial aspect of ZTA implementation is adopting strict identity and access management (IAM) policies. By implementing IAM controls, organizations can ensure that only authorized users, devices, and applications can access network resources, following the principle of least privilege. Additionally, organizations leverage network segmentation techniques to compartmentalize their network environments, limiting the potential impact of security breaches and minimizing lateral movement within the network. Furthermore, ZTA implementation often involves the deployment of multi-factor authentication (MFA) mechanisms, adding an extra layer of security to verify user identities. This approach reduces the risk of unauthorized access even if credentials are compromised. Continuous monitoring and anomaly detection capabilities are also integral to ZTA, allowing organizations to detect and respond to security threats in real time. Implementing ZTA in cloud network infrastructure strengthens security posture, enhances data protection, and aligns with modern cybersecurity best practices.

Mathematical Models for Analyzing Zero Trust Effectiveness

Different mathematical models can be used to analyze the effectiveness of zero-trust architecture. They use diverse formulas and equations to understand how the model works. According to [START_REF] Mehraj | Establishing a zero trust strategy in cloud computing environment[END_REF], zero trust is a digital bodyguard for different network systems. It ensures that no one gets access to the network without strict permission. The use of mathematical calculations in this process is essential. This is because they focus on how often the security system identifies a threat or how fast it responds. Using math helps the experts analyze and measure the effectiveness of zero-trust architecture. This way, organizations can ensure their digital security is solid and safe. Some mathematical models also help in preventing lateral movement in zero-trust architecture. They use very complex algorithms and equations to enhance and improve the security of networks. According to [START_REF] Alevizos | Augmenting zero trust architecture to endpoints using blockchain: A state-of-the-art review[END_REF], such models help develop digital checkpoints and barriers to stop different attackers from intruding into the network. Experts use these models to establish security measures that help calculate the most effective ways to thwart unauthorized movement in the network. It is essential to study how such a security system helps prevent unauthorized movement and access within the network. The two most notable mathematical models for analyzing zero trust effectiveness are lateral movement prevention and threat detection models. The lateral prevention model is designed to assess and mitigate the spread of cyber threats within a network environment post-breach. Formula 1 shows how the reduction in lateral movement is calculated.

Reduction in Lateral Movement = (1)

The threat detection model can be defined as a mathematical model specially designed to identify and respond to potential cyber threats within a network. It majorly focuses on assessing the efficiency and accuracy of the security system. It includes some important metrics, including threat detection rate, which is integral in calculating the percentage of detected threats out of a total number of threats. Formula 2 shows how the threat detection rate is calculated.

Threat Detection Rate = (2)

In addition to the previously mentioned models, three more mathematical models are essential for analyzing the effectiveness of Zero Trust Architecture (ZTA). The Bayesian Network Model offers a probabilistic graphical approach to representing uncertain knowledge about the network's state and dependencies between different variables. Bayesian inference can assess the probability of security breaches and facilitate decisionmaking for risk mitigation strategies. Formula 3 shows how to calculate this.

(A|B) = (3)

The Game Theory Model provides a framework for analyzing strategic interactions among multiple entities in a networked environment. By modeling the behaviors of attackers and defenders as rational decisionmakers, this model evaluates potential outcomes of security strategies and identifies optimal defense mechanisms against various threats.

Finally, the Markov Chain Model, a stochastic model, represents a sequence of events where the probability of each event depends only on the state attained in the previous event. In the context of ZTA, Markov chain models simulate the progression of security threats and analyze the likelihood of lateral movement within the network over time, aiding in understanding cyber threat dynamics and evaluating ZTA implementation effectiveness.

Enhancing Access Management to Mitigate Insider Threats with Zero Trust

Insider threats have become very common in cloud networks. They can be of different types as well. The most common is the malicious insider threat. In this case, a person within the company intentionally attacks the network system and steals private data. Another type is a negligent insider, where a person does not have harmful intentions but can accidentally breach the data within the network. According to [START_REF] Kim | A review of insider threat detection approaches with IoT perspective[END_REF], this threat is caused because of careless actions of the person. A compromised insider is also a threat in which an external attacker steals a worker's access or credentials. All these types of threats pose different risks to the system. It can lead to theft or loss of sensitive information. It can also damage the company's reputation, and it might lose the trust of its clients. Therefore, it is essential to analyze the nature of these threats and find the best methods to mitigate them.

The zero trust model helps in overcoming insider threats in many ways. This system assumes that no single person should be trusted. It thus checks the people inside the network as well. For this purpose, the system uses role-based access controls (RBAC). According to [START_REF] Yao | Dynamic access control and authorization system based on zero-trust architecture[END_REF], zero trust architecture uses RBAC to ensure that people only have the necessary permissions based on their responsibilities within the company. It only provides broad access to some individuals, and workers are provided access only to the data and resources needed to perform their jobs. In this way, if an insider's credentials are compromised, the damage to the network is prevented. It also helps implement the principle of least privilege, reducing the attack surface and limiting insider threats' negative influence [START_REF] He | A survey on zero trust architecture: Challenges and future trends[END_REF].

Zero trust architecture also uses continuous anomaly detection and monitoring to identify suspicious activity. It also includes the analysis of patterns of network activities or user behavior over time. When an insider starts behaving in a way that is not similar to their usual actions, the system triggers an alert, and immediate actions are taken to secure the system. Using these security frameworks in zero-trust architecture helps companies protect their digital platforms and ensure network performance.

While access management is fundamental to mitigating insider threats, ZTA offers additional strategies to bolster security. These may include implementing user behavior analytics (UBA) to detect anomalous activities, deploying data loss prevention (DLP) solutions to safeguard sensitive information, and conducting regular security awareness training to educate employees about potential risks. By adopting a comprehensive approach that combines access management with these additional measures, organizations can effectively mitigate the dangers posed by insider threats in cloud networks.

Theme Relevant Studies

Methodologies Employed

Key Findings

Impact of ZTA on Lateral Movement

[1], [START_REF] Livera | Zero Trust -Modern Security Architecture[END_REF], [START_REF] Stafford | Zero trust architecture[END_REF] Thematic analysis, comparative analysis

Significant reduction in lateral movement incidents post-ZTA implementation; Improved threat containment Reduction of Insider Threat Probability [START_REF] Sadeeq | IoT and Cloud computing issues, challenges and opportunities: A review[END_REF], [START_REF] Fernandez | A critical analysis of Zero Trust Architecture (ZTA)[END_REF], [START_REF] Syed | Zero trust architecture (zta): A comprehensive survey[END_REF] Literature review, case studies Decrease insider threat incidents; Financial impact reduction; Increased user behavior monitoring.

Effectiveness of Network

Micro-Segmentation [START_REF] Xie | A micro-segmentation protection scheme based on zero trust architecture[END_REF], [START_REF] Khan | Zero trust architecture: Redefining network security paradigms in the digital age[END_REF], [START_REF] Chen | A security awareness and protection system for 5G smart healthcare based on zero-trust architecture[END_REF] Quantitative analysis, interviews Enhanced network traffic control; Improved visibility; Minimization of security incident scope Enhancements in Identity and Access Management [START_REF] Froehlich | Why zero trust requires microsegmentation[END_REF], [START_REF] Tyler | Trust no one? a framework for assisting healthcare organisations in transitioning to a zero-trust network architecture[END_REF], [START_REF] Mehraj | Establishing a zero trust strategy in cloud computing environment[END_REF] Surveys, experimental research Streamlined IAM processes; Automated user provisioning; Real-time threat detection Encryption and Data Protection [START_REF] Alevizos | Augmenting zero trust architecture to endpoints using blockchain: A state-of-the-art review[END_REF], [START_REF] Yao | Dynamic access control and authorization system based on zero-trust architecture[END_REF], [START_REF] Shitta-Bey | Security Concerns of Cloud Migration and Its Implications on Cloud-Enabled Business Transformation[END_REF] Observational studies, content analysis Strengthened data security; Compliance with privacy laws; Encryption benefits for data-atrest and in-transit Best Practices for ZTA Implementation [START_REF] Kim | A review of insider threat detection approaches with IoT perspective[END_REF], [START_REF] He | A survey on zero trust architecture: Challenges and future trends[END_REF], [START_REF] Agrawal | Defense mechanisms against DDoS attacks in a cloud computing environment: State-of-the-art and research challenges[END_REF] Case studies, expert interviews Importance of regulatory compliance; Mapping of network connections; Continuous authentication methods Comparative Analysis Before and After ZTA Implementation [START_REF] Fortra Terranova | How Secure is Cloud Storage? Here are the Important Risks to Know[END_REF], [START_REF] Milan | Nature inspired meta-heuristic algorithms for solving the load-balancing problem in cloud environments[END_REF], [START_REF] Singh | IAM identity Access Management-importance in maintaining security systems within organizations[END_REF] Meta-analysis, longitudinal studies Reduction in security incidents; Unauthorized access decrease; Enhanced access controls and verification Future Advancements of ZTA in Cloud Networks [START_REF] Steingartner | Threat defense: Cyber deception approach and education for resilience in hybrid threats model[END_REF], [START_REF] Tian | Real-time lateral movement detection based on evidence reasoning network for edge computing environment[END_REF], [START_REF] Wiz | Lateral Movement Explained[END_REF] Trend analysis, expert opinions Integration with AI and ML; Enhanced monitoring and visibility; Dynamic policy management

PROBLEM DEFINITION

The addition of cloud computing in the system has changed the digital system, which offers organizations different opportunities for efficiency. In addition, this change has come with its security challenges. As businesses transform their data and operations to the cloud, there are issues of safeguarding sensitive information [START_REF] Shitta-Bey | Security Concerns of Cloud Migration and Its Implications on Cloud-Enabled Business Transformation[END_REF]. This section adds to organizations' different problems in securing cloud networks, which increases the need for a robust security system like the Zero Trust Architecture (ZTA).

Increased Attack Surface

One of the main challenges in securing cloud networks is the increase in attacks [START_REF] Agrawal | Defense mechanisms against DDoS attacks in a cloud computing environment: State-of-the-art and research challenges[END_REF]. Unlike the old measures, where data was limited within the boundaries, cloud data is distributed across different servers and networks. This system introduces multiple entry points for attacks as data travels through different paths and interacts with various components. The extensive nature of the cloud increases the hurdles of monitoring and defending against attacks, which necessitates a shift from security models. Figure 3 depicts challenges in cloud security.

Dynamic Nature of Cloud Environments

The cloud system is characterized by its specific nature, which allows organizations to increase resources based on demand [START_REF] Milan | Nature inspired meta-heuristic algorithms for solving the load-balancing problem in cloud environments[END_REF]. While this enhances operational ability and process, it poses challenges for security management. Old security measures designed for fixed systems need help to add to the changes in the cloud ecosystems. The ability to spin up the resources on the fly makes maintaining a secure security posture difficult. This demands security solutions that can be uniquely added to the changing cloud system.

The Complexity of Identity and Access Management

Identity and Access Management (IAM) has become increasingly difficult in the cloud system, given the limited range of users, devices, and applications accessing resources [START_REF] Singh | IAM identity Access Management-importance in maintaining security systems within organizations[END_REF]. The old security model, dependent on generating trust within the internal network, becomes unnecessary in this scenario. Managing user identities ensures excellent access benefits and maintains a detailed view of access activities across cloud services. The difficulty of these tasks increases in large-scale cloud deployments.

Evolution of Sophisticated Cyber Threats

The cybersecurity system is changing at a unique limit, with threat actors using polished tactics, techniques, and procedures to utilize the weaknesses [START_REF] Steingartner | Threat defense: Cyber deception approach and education for resilience in hybrid threats model[END_REF]. Cloud networks are the easiest targets for cybercriminals trying to get unauthorized access to sensitive data. Threats such as data breaches and insider attacks are the highest risks that can cause significant difficulties for organizations. The old security measures, which may have been influential in the past, need help to act efficiently with the constantly changing tactics forced by cyber adversaries.

Lateral Movement and Insider Threats

Cloud networks have many security problems, including lateral movement and insider threats [START_REF] Tian | Real-time lateral movement detection based on evidence reasoning network for edge computing environment[END_REF]. Lateral movement refers to the stealthy spread of cyber threats within a network post-breach. Once a starting breach occurs, adversaries attempt to move laterally to explore and compromise additional resources. Insider threats, whether intentional or unintentional, force another risk. Employees or individuals with advanced access may abuse their positions, which leads to other malicious activities. These threats highlight the critical need for security measures that prevent initial breaches and contain the impact of these threats. Figure 4 shows how lateral movement works.

The Need for a Robust Security Framework

Given the intricate nature of these challenges, there is a high need for a robust security system that can act as a shield to cloud networks. Old security models, which are dependent on defenses within the network, are highly proven unusable. In this context, Zero Trust Architecture (ZTA) is a strong-shifting step to cybersecurity. By challenging the old trust measures and utilizing continuous verification and the least special access, ZTA solves the unique security challenges forced by cloud environments [START_REF] Fernandez | A critical analysis of Zero Trust Architecture (ZTA)[END_REF]. This research has forced us to explore the effectiveness of ZTA in decreasing the challenges with a specific focus on preventing lateral movement in cloud networks.

METHODOLOGY AND APPROACH

Rationale

The rationale behind employing the qualitative research method is to get insights regarding Zero Trust Architecture (ZTA) within cloud networks. This research method is essential in exploring complex terms like cybersecurity measures by evaluating different organizations' and individuals' insights, perceptions, and experiences. Moreover, the qualitative research method discovers various aspects of implementing ZTA and its effectiveness when addressing security challenges in cloud environments. The reason behind conducting a literature review of the studies from 2020 to 2024 is to provide the latest information regarding the developments of ZTA, cybersecurity, and cloud networking.

Data Selection

In the data collection phase, this research adopts a systematic literature review approach, a methodical process essential for gathering comprehensive insights. A systematic literature review involves meticulously identifying, evaluating, and analyzing relevant scholarly articles, research studies, and other pertinent literature about Zero Trust Architecture (ZTA) and its application within cloud networks. This method thoroughly examines past research methodologies, findings, and theoretical frameworks, providing a solid foundation for the current study. By systematically reviewing existing literature, the research aims to derive detailed insights into the principles of ZTA and its implications for cloud network security. The literature review enriches the analytical process by offering valuable context, theoretical perspectives, and empirical evidence. Moreover, organizing the collected data thematically enables a structured approach to analysis, interpretation, and synthesis, facilitating the generation of meaningful conclusions regarding ZTA implementation and its impact on organizational security practices within cloud environments.

Data Collection

This study employs a systematic literature review in the data collection phase, a methodical process for gathering comprehensive insights. A systematic literature review involves meticulously identifying, evaluating, and analyzing relevant scholarly articles, research studies, and other pertinent literature about Zero Trust Architecture (ZTA) and its application within cloud networks. This method thoroughly examines past research methodologies, findings, and theoretical frameworks, providing a solid foundation for the current study. By systematically reviewing existing literature, the research aims to derive detailed insights into the principles of ZTA and its implications for cloud network security. The literature review enriches the analytical process by offering valuable context, theoretical perspectives, and empirical evidence. Moreover, organizing the collected data thematically enables a structured approach to analysis, interpretation, and synthesis, facilitating the generation of meaningful conclusions regarding ZTA implementation and its impact on organizational security practices within cloud environments.

Recruitment

Analytical Process

The analytical process includes the thematic analysis in which all the data is divided into themes so that all the information can be organized in sections and easily access helpful information. Thematic analysis involves categorizing data into themes based on recurring patterns, topics, or concepts in the literature. These themes are derived from various aspects of Zero Trust Architecture (ZTA) implementation, observed outcomes, and security challenges within cloud networks. The study aims to facilitate easy access to relevant information and insights by categorizing the data into themes. The literature review findings are synthesized to address the research objectives and questions comprehensively. Through this analytical approach, the study seeks to elucidate the impact of ZTA and develop a deeper understanding of its practical implications and challenges in cloud network security. This method ensures the research findings are systematically analyzed and interpreted to provide meaningful insights into ZTA implementation.

Methodology Phase Outputs Obtained 1. Problem Identification

Defined research questions and objectives

Literature Review

Identified relevant studies, methodologies, and insights

Data Selection

Selected resources related to ZTA implementation and impact

Data Collection

A systematic literature review was conducted.

Recruitment

Relevant studies, reports, and research papers selected 6. Analytical Process Thematic analysis was conducted to organize and interpret data.

Results and Discussion

Findings from the literature review analyzed and discussed

RESULTS AND DISCUSSION

Lateral Movement Analysis

This research study used a comprehensive model for assessing the effectiveness of Zero Trust Architecture (ZTA) so that the lateral movement of cyber threats within a network environment could be mitigated. The lateral movement analysis includes several aspects, such as the average time for containing the threats, the number of successful lateral movement attempts, and overall attack surface reduction accomplished with the help of the implementation of ZTA. His research demonstrates a significant decrease in lateral movement incidents that occur due to the adoption of ZTA. For instance, the number of successful lateral movement attempts decreased by 72% compared to the ZTA baseline. On the other hand, some organizations faced a reduction of about 90%. Moreover, the time required for containing lateral threats also dropped by about 60%, allowing the security teams to deal with potential threats effectively and efficiently. Formula 4 shows how to calculate successful lateral movement attempts.

LMA = (4)

The significant factors that can lead to these reductions include continuous monitoring, network segmentation, least privilege access, and Multi-Factor Authentication (MFA). For instance, the network is divided into smaller segments, so ZTA can restrict the attackers' potential pathways to move laterally. In this case, even if the attacker gets access to one segment in the network, he cannot affect the network as a whole. Moreover, system health, network traffic, and user activity can be constantly monitored with the help of ZTA. This leads to detecting the errors and threats early so that expert security teams can protect the overall system. n addition, according to ZTA, the users are provided with limited access to the resources; it means they only get access to those used for performing their tasks.

Insider Threat Probability

Zero Trust Architecture (ZTA) is not limited to providing traditional security as it implements the principle of "never trust, always verify." This means all the users are verified before giving access to the system, regardless of whether they are already users of that network. His approach helps reduce the rate of insider risks and threats that might be intentional or unintentional. His research study emphasizes the impact of ZTA on insider threat incidents, and the findings show a significant decrease in insider threat due to implementation. For example, the number of insider threats has decreased by about 65%, and the financial impact of these insider threats has also reduced by 40%.

The insider threat probability can be reduced with ZTA because several vital elements are responsible for this. For example, User Behavior Analytics (UBA) helps monitor user activity and detect changes in routine behavior patterns [START_REF] Martín | A survey for user behavior analysis based on machine learning techniques: current models and applications[END_REF]. He helps detect the threats in the initial stage so they can be mitigated promptly. Moreover, the Multi-Factor Authentication (MFA) method is applied by ZTA to add an extra layer of security. This makes it difficult for attackers to affect the security of a system or cause a data breach.

Network Micro-Segmentation Effectiveness

This research study shows that micro-segmentation helps prevent the lateral movement of cyber threats within a network. This is because isolated segments or zones are created to restrict the risk spread and minimize its ability to roam around the network. Moreover, the implementation of micro-segmentation is practical when it comes to controlling network traffic. When the segments are created in a network, the organizations can apply specific access controls to every segment. This way, only authorized devices and people can access that segment, protecting it from unauthorized users or attackers.

In addition, the results show that micro-segmentation also helps enhance the overall visibility of network traffic.

Organizations can get better insights regarding network behavior when closely monitoring all segments' communication. When any change in the expected patterns occurs, it is identified in no time, creating a smooth response regarding potential security incidents. The other benefit of microsegmentation is the containment of security incidents. If one segment is attacked, the others can be protected so that the scope of potential damage can be minimized and a more efficient response can be facilitated for dealing with security incidents.

Identity and Access Management (IAM) Enhancements

Identity and access management (IAM) enhancements play an essential role in the framework of zero-trust architecture in cloud networks, leading to enhanced security measures and access control [START_REF] Olabanji | AI for Identity and Access Management (IAM) in the Cloud: Exploring the Potential of Artificial Intelligence to Improve User Authentication, Authorization, and Access Control within Cloud-Based Systems[END_REF]. Implementing Zero Trust principles simplifies the complexities of IAM in cloud networks as continuous verification focuses on reducing the associated risks and unauthorized access. Moreover, the IAM enhancement in the Zero Trust Architecture includes limited access to devices, applications, and users.

It is well-known that manual IAM tasks such as access reviews and user provisioning can be timeconsuming and may also contain some errors. ZTA has resolved this issue by automating such processes. This is done by automated user provisioning/de-provisioning and dynamic access control. Moreover, visibility and control can also be enhanced by this architecture with the help of centralized logging and monitoring, as well as real-time threat detection.

Encryption and Data Protection

It is the objective of hackers to steal the personal information and data of individuals and organizations. That's why it is essential to focus on implementing a robust model or system for enhancing overall security. The Zero Trust Security model focuses on increasing the organization's data security and integrating current laws to provide flexibility for adopting future security and privacy laws [START_REF] Thapa | Precision health data: Requirements, challenges and existing techniques for data security and privacy[END_REF]. Ata security is the primary goal of this model because hackers are always trying to steal confidential data. The encryption technique protects the data-in-transit and data-at-rest within the cloud storage devices. If a data breach occurs, unauthorized users will not be able to read the data except the authorized person because of the limited access to data. Figure 5 shows the key features of encrypted cloud storage.

Best Practices to Implement Zero Trust

Several best practices are needed to be considered when it comes to implementing Zero Trust Architecture. First, it is necessary to understand the protection surface, which means regulatory compliance standards and guidelines like the General Data Protection Regulation (GDPR) must be detailed because they are essential for organizations to identify and secure the data effectively and efficiently [START_REF] Stalla-Bourdillon | Data protection by design: Building the foundations of trustworthy data sharing[END_REF]. Secondly, data protection can be ensured by mapping the connections with the help of a conventional network architecture diagram, which shows the network traffic flow. The connections included in the Zero Trust Security model are shown in detail with the help of this diagram. The mapping of applications in use, data transmission connections, and data associated with the applications are also demonstrated through it.

Comparative Analysis Before and After ZTA Implementation

Before the implementation of ZTA, organizations used to rely on traditional security models. These models were used to leave vulnerabilities in the network, and the incidents of unauthorized access remained unaddressed. Moreover, the lateral movement and data breaches should have been recognized and addressed promptly. This is because security incidents significantly and adversely impacted the overall network. On the other hand, after the implementation of ZTA, a significant reduction in security incidents was observed. Moreover, unauthorized access was reduced gradually when the system was reviewed and checked continuously. Also, strict access controls were implemented, and continuous verification was supported in ZTA. Ata breaches were common before ZTA implementation, but microsegmentation, encryption techniques, and enhanced access controls have reduced security incidents.

CONCLUSION

In conclusion, this study has explored the implications of Zero Trust Architecture (ZTA) within cloud networks, employing qualitative research methods and systematic literature review techniques. The findings underscore the effectiveness of ZTA in mitigating security threats, particularly in addressing insider threats and lateral movement incidents and enhancing data protection measures. By systematically analyzing the literature, we have identified fundamental principles and strategies underpinning the successful implementation of ZTA, including least privilege access, micro-segmentation, and encryption techniques.

Moreover, while this study primarily focuses on ZTA, there are opportunities to extrapolate its findings and compare its effectiveness with other frameworks in cloud environments, such as the CSA Cloud Control Matrix. Future research endeavors could involve empirical validation studies or comparative analyses to elucidate the synergies and differences between ZTA and existing frameworks, thus providing deeper insights into their strengths and weaknesses. Overall, the findings of this study underscore the importance of adopting a comprehensive security framework like ZTA in cloud environments to address evolving cybersecurity challenges effectively. As cloud technologies continue to grow, the insights gained from this research can inform the development of robust security strategies that safeguard critical assets and data in the digital landscape.

FUTURE SCOPE

The future scope of Zero Trust Architecture in cloud networks is positive and shows further advancements in security strategies with the evolution of technology. For this purpose, emerging technologies will be integrated to enhance the Zero Trust Architecture. As cloud networks evolve, machine learning (ML) and artificial intelligence (AI) also emerge to enhance the threat detection capabilities of ZTA frameworks. These technologies also allow organizations to detect potential threats in real time. Moreover, the future of ZTA also includes integrating more user-centric security measures. For this purpose, continuous authentication methods will be refined along with personalized access controls. ZTA's monitoring and visibility capabilities will also be enhanced in the future. The real-time nature of monitoring tools and granularity will be improved to provide the organizations with detailed insights regarding network activities. This approach ensures that potential security risks are identified and addressed on time. Moreover, dynamic policy management will be encouraged to enhance the cloud environments. Eal-time-based tools will be used to develop a flexible security framework based on different factors such as network conditions, device status, and user location.

Fig. 1 .

 1 Fig. 1. Zero Trust Architecture [3]

Fig. 3 .

 3 Fig. 3. Cloud Security Challenges[START_REF] Fortra Terranova | How Secure is Cloud Storage? Here are the Important Risks to Know[END_REF]

Fig. 4 .

 4 Fig. 4. Lateral Movement in Cybersecurity[START_REF] Wiz | Lateral Movement Explained[END_REF]

Fig. 5 .

 5 Fig. 5. Key Features of Encrypted Cloud Storage[START_REF] Basumallick | Top 10 Encrypted Cloud Storage Platforms for Enterprises in 2021[END_REF]

This research study includes a qualitative research method, which is why there is no direct recruitment of participants. This includes selecting relevant studies, reports, and research papers that provide valuable insights regarding the research questions. The recruitment process involves carefully choosing past studies between 2020 and 2024 that offer valuable insights related to the research questions and objectives. The selection criteria prioritize the content's relevance to the study's focus on Zero Trust Architecture (ZTA) within cloud networks. By curating a comprehensive dataset from diverse and relevant sources, the research aims to enrich the qualitative analysis and thoroughly explore ZTA's implications and effectiveness in cloud security. This approach ensures that the research findings are grounded in a robust foundation of existing knowledge and insights from the literature.