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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Approach, October</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>Serverless computing for data processing in open learning and research environments</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Ihor A. Bezverbnyi</string-name>
          <email>ihorbezverbnyi@gmail.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
          <xref ref-type="aff" rid="aff2">2</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Mariya P. Shyshkina</string-name>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Institute for Digitalisation of Education of the NAES of Ukraine</institution>
          ,
          <addr-line>9 M. Berlynskoho Str., Kyiv, 04060</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Kyiv</institution>
          ,
          <addr-line>03187</addr-line>
          ,
          <country country="UA">Ukraine</country>
        </aff>
        <aff id="aff2">
          <label>2</label>
          <institution>V. M. Glushkov Institute of Cybernetics of the National Academy of Sciences of Ukraine</institution>
          ,
          <addr-line>40 Academician Glushkov Ave.</addr-line>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2023</year>
      </pub-date>
      <volume>25</volume>
      <issue>2022</issue>
      <fpage>229</fpage>
      <lpage>236</lpage>
      <abstract>
        <p>Serverless computing is a paradigm that enables the execution of code without provisioning or managing servers. It ofers benefits such as scalability, cost-eficiency, and ease of development for cloud-based applications. In this paper, we explore the potential of serverless computing for supporting data processing in open learning and research environments. We propose a concept of a hybrid serverless cloud, which combines diferent types of cloud services to provide access to various tools and resources for learners and researchers. We present a case study of wave files processing using a lambda function, which demonstrates the feasibility and efectiveness of our approach. We also discuss the challenges and opportunities of integrating serverless components within open systems of learning and research. Finally, we present a vision of a cloud-based open learning and research university environment that leverages serverless technologies to enhance the quality and accessibility of education and research.</p>
      </abstract>
      <kwd-group>
        <kwd>serverless computing</kwd>
        <kwd>cloud computing</kwd>
        <kwd>data processing</kwd>
        <kwd>open learning</kwd>
        <kwd>open research</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Cloud-based learning and research environments are emerging as a key paradigm for
modernizing the educational process in higher education and fostering open science within the
European Research Area [
        <xref ref-type="bibr" rid="ref1 ref2">1, 2, 3</xref>
        ]. Cloud technologies enable the creation of more convenient,
lfexible, and scalable systems for accessing electronic resources and services in learning and
research activities, as well as facilitating collaboration, mobility, and overcoming geographical
and temporal barriers [4, 5, 6, 7, 8, 9, 10]. This provides a basis for implementing the principles
and technologies of open science for a wider range of users, such as creating and operating
virtual research teams, improving scientific communication processes, accessing and sharing
data in the research process, disseminating research results, and engaging with society [11].
Cloud computing tools and services form an information technology platform for the modern
educational and scientific environment, becoming a network tool for shaping this environment
nEvelop-O
LGOBE
[12]. Therefore, it is important to analyze the trends and challenges of integrating cloud data
processing services into the activities of researchers and educational or research institutions.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. The research results</title>
      <sec id="sec-2-1">
        <title>2.1. The background issues</title>
        <p>Cloud computing ofers various models, such as IaaS, PaaS and SaaS, that can facilitate learning
and research data processing. By abstracting resources and providing simple automation tools,
modern cloud platforms simplify many routine tasks, such as installation, maintenance, backup,
security, and more [5, 13]. Moreover, in the context of open science, open data and big data
processing are essential. To meet the requirements of open science systems design, large
amounts of data need to be available and accessible for joint processing by the community of
scientists [5]. Therefore, cloud computing platforms can serve as a reasonable framework to
support open learning and research processes, both in terms of managing and processing large
amounts of data and making them available for collaborative use [5].</p>
        <p>
          The computing capacity is crucial for processing and retrieving large amounts of data, which
are needed at most stages of the research process, such as data collection, representation,
visualization, analysis, interpretation and discussion. A possible way to save resources and
provide flexible use of the cloud-based infrastructure is to use lambda functions within the
serverless settings. This leads to the notion of Function-As-A-Service (FAAS) as a promising
cloud-based model [
          <xref ref-type="bibr" rid="ref3">14, 12, 15, 16</xref>
          ].
        </p>
        <p>
          The applications and evaluation of serverless computing in diferent areas are among the
current issues considered nowadays, for example for machine learning [
          <xref ref-type="bibr" rid="ref4">17</xref>
          ], network functions
virtualization [
          <xref ref-type="bibr" rid="ref5">18</xref>
          ], geospatial architectures [
          <xref ref-type="bibr" rid="ref6">19</xref>
          ]. Casale et al. [
          <xref ref-type="bibr" rid="ref7">20</xref>
          ] propose a platform for
decomposition and orchestration for serverless computing. Ortiz [
          <xref ref-type="bibr" rid="ref8">21</xref>
          ] present architecting
serverless microservices on the cloud with AWS and also issues of instructors training to use
these technologies. However, the area of educational application of serverless technologies to
provide better use and implementation for learning and research within the university sector
is poorly investigated and needs further research. There is a need to consider methodological
issues and possible ways of serverless technology application within the open learning and
research university environment.
        </p>
        <p>The article aims to consider and evaluate a hybrid cloud-based serverless architecture as a
possible open learning and research platform to support data processing and research
collaboration. The main idea is that design and development of learning and research environment
due to the proposed approach will result in more eficient use of the cloud-based resources,
better access to learning and research data and collaboration support. The case study of the
sound signal processing as a possible example of serverless approach application for learning
and research is considered.</p>
      </sec>
      <sec id="sec-2-2">
        <title>2.2. The conceptual basis</title>
        <p>The paper introduces the main concepts and terms related to the design and development of
university cloud-based learning and research environment (LRE), based on the principles of
open science, open education, and cloud-oriented systems, as proposed by Bykov and Shyshkina
[4].</p>
        <p>The LRE of a higher education institution is defined as an environment that leverages the
virtualized computer-technological infrastructure (corporate or hybrid-based) to support the
content-technological and information-communication functions of learning and research
activities [4].</p>
        <p>
          Serverless technologies are adopted to build applications that require dynamic and
unpredictable computing resources. The serverless hybrid cloud architecture enables the deployment
of lambda-functions [
          <xref ref-type="bibr" rid="ref9">22</xref>
          ], which are cloud-based services that execute computing tasks on
demand within the cloud-based infrastructure of a provider, without requiring the user to create
and manage the server architecture.
        </p>
      </sec>
      <sec id="sec-2-3">
        <title>2.3. The model and approach</title>
        <p>Figure 1 illustrates the configuration of the serverless application architecture.</p>
        <p>The proposed approach is to access lambda-functions through API Gateway, avoiding server
management as lambda-functions return the values in static HTML format, which are stored
and retrieved on S3-bucket, and can be further processed.</p>
        <p>This approach allows the user to access specific electronic resources and computing capacities
hosted on a hybrid serverless architecture from any device with an Internet connection.</p>
        <p>The advantage of this approach is that it provides flexibility and scalability for learning or
research processes that need computing resources for special purposes that may arise
occasionally. For example, in the course of an experimental research, big data processing may be
needed that require high computing power for a short time. It may be ineficient to maintain
and manage a cloud server for these purposes. However, by using lambda-functions, the learner
or researcher can access a server with powerful processing capabilities without deploying it
every time as the function is needed. The necessary resources can be supplied more eficiently
on demand.</p>
      </sec>
      <sec id="sec-2-4">
        <title>2.4. Current developments and implementation</title>
        <p>The cloud-based LRE was implemented at the Institute for Digitalisation of Education of the
NAES of Ukraine as part of the research projects and pedagogical experiments conducted from
2012 to 2017. During this period, various cloud-based services were integrated into the research
and educational process to support open education and open science [4].</p>
        <p>In 2018, the V4+ Academic Research Consortium Integrating Databases, Robotics and
Language Technologies was established, which aimed to address regional issues related to EU ICT
research priorities. The consortium used the following cloud-based components for collaborative
work:
• The BOX Cloud shared work-space – a cloud storage and transfer service that connected
the researchers’ computers and allowed them to share documents.
• The virtual machine with Windows 10 – a remote desktop that provided a common
computing environment for the partners [5].</p>
        <p>The cloud-based components that were developed and tested during this period were also
applied in the learning process. The course “Cloud Computing Technologies’’ was designed and
introduced in National University of Life and Environmental Sciences of Ukraine for training
computer science bachelors. The students learned how to build cloud-based components on
virtual machines using AWS and Azure platforms. The methodology of open learning and
research platform implementation proved to be efective.</p>
        <p>The next step of the research was the creation of the serverless hybrid cloud architecture
to support collaborative research with Kyiv Glushkov Institute of Cybernetics of the NAS
of Ukraine. The goal was to use lambda-functions for sound signal processing and analysis.
Figure 2 shows an example of a sound signal oscillogram generated by a lambda-function.</p>
        <p>The serverless environment was used for the following tasks:
1. A Python-based web application was created using the Flask framework and tested on
localhost.</p>
        <p>2. A user account with necessary permissions was created in the AWS console to secure
future applications. An S3 bucket and an EC2 server were also created in the AWS console.
The working folder with the Python script (or another compatible language for AWS
Lambda) was uploaded to S3.
3. To enable the processing, one or more layers with the required libraries were attached
to the lambda-function. The libraries were installed in a virtual environment on the
EC2 server. An additional layer was created from this environment. AWS Lambda also
provides some freely distributable layers that can be used in future applications.
4. A YAML file was created using CloudFormation tool to specify the available resources
for the application. The YAML file created a separate role for working with the future
application.</p>
        <p>4.1 Using this role, a lambda-function was created, and its code was downloaded
from the zip file created in S3.</p>
        <p>4.2 Using this role, an API Gateway was created to allow calling the lambda-function
from a browser.
5. The application was debugged and tested.</p>
        <p>Using this sequence of steps, a hybrid environment with lambda-function was created and
tested for sound signal processing.</p>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3. Conclusion</title>
      <p>The paper has presented the rationale and the methodology for introducing cloud technologies
in the educational and research process of higher education institutions, as well as the design
and implementation of the learning and research environment based on these technologies.
The paper has demonstrated how cloud technologies can enhance the access to electronic
educational resources, improve the eficiency of ICT infrastructure, and support open education
and open science principles. The paper has also proposed a novel approach for using serverless
technologies to provide cloud services for data processing, visualization and retrieval, which is a
relevant and promising area of development and modernization of the university open learning
and research environment.</p>
      <p>The paper has reported the experience of developing and applying various cloud-based
components for educational and scientific purposes based on the proposed architecture of the
hybrid cloud-based environment with lambda-functions. The paper has shown how
lambdafunctions can enable flexible and scalable computing resources for learning or research tasks
that require dynamic and unpredictable computing power.</p>
      <p>This approach still needs further implementation and evaluation in diferent contexts and
domains. Future work will focus on expanding the functionality and usability of the cloud-based
components, as well as assessing their impact on learning outcomes and research quality.
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