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  <front>
    <journal-meta>
      <journal-title-group>
        <journal-title>Workshops, Doctoral Symposium, and
Poster &amp; Tools Track, Birmingham, UK</journal-title>
      </journal-title-group>
    </journal-meta>
    <article-meta>
      <title-group>
        <article-title>An Intelligent Systems Approach for Supporting Privacy Awareness in Agile Software Development</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Guntur Budi Herwanto</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>Department of Computer Science and Electronics</institution>
          ,
          <addr-line>Universitas Gadjah Mada</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Faculty of Computer Science, University of Vienna</institution>
        </aff>
      </contrib-group>
      <pub-date>
        <year>2022</year>
      </pub-date>
      <volume>2</volume>
      <fpage>1</fpage>
      <lpage>03</lpage>
      <abstract>
        <p>Privacy by design principles is an established standard guiding the design and development of privacyaware systems. Privacy engineering acts as a role to close the gap between the privacy policy and the realization of the system or technology that will be developed. Many privacy engineering methodologies depend heavily on a waterfall-style approach that can be very time-consuming and is not tailored to the speed of agile process, which the majority of the industry is currently taking. In this research, we aim to address those challenges by an intelligent system approach in the form of a natural language processing and recommendation system. As a scientific basis, we use experimental design research to evaluate our intelligent systems that will be integrated in privacy requirements and design context. With this research, we intend to contribute to the advancement of privacy engineering in an agile environment by providing a system that allows better integration of privacy protection with currently used development processes, such as Scrum.</p>
      </abstract>
      <kwd-group>
        <kwd>eol&gt;privacy engineering</kwd>
        <kwd>privacy requirement</kwd>
        <kwd>agile software development</kwd>
        <kwd>intelligent system</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1. Introduction</title>
      <p>
        Tailoring privacy aspects into the software development process has become a key concern
and challenge for the industry. Privacy engineering has emerged as a research framework that
focuses on adapting privacy into organizational and technical measures [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. Privacy engineering
is integrated into the software development life cycle (SDLC), including the requirements and
design phase. The requirements phase can therefore be referred to as privacy requirement
engineering. Many privacy requirements engineering methodologies depend heavily on a
waterfall-style approach that can be time-consuming and not tailored to the agile speed that
much of the industry is currently taking. Researchers have studied these challenges and clearly
state the conflicting nature of agile software development (ASD) and privacy engineering [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ].
      </p>
      <p>
        The agile turn makes modeling privacy threats or designing a privacy-aware system become
more challenging [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. According to the findings of a study on legal compliance within agile
teams, the teams did not know how to identify privacy principles in user requirements [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. They
believe it is challenging to incorporate privacy considerations into the development process [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ].
To overcome this, researchers are developing the method that can suit to the agile process [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ],
or proposing the lean process on privacy engineering. [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. Tool support is also proposed as a
way to capture the privacy requirement in agile situation [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ].
      </p>
      <p>
        Intelligent software engineering (ISE) has long been used in ASD [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Perkusich [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ] refers
ISE as "the application of intelligent techniques to software engineering". In addition, they defined
intelligent technique as "a technique that explores data (from digital artifacts or domain experts)
for knowledge discovery, reasoning, learning, planning, natural language processing, perception or
supporting decision-making". The implementation of the ISE has the purpose of helping better
manage and even accelerate the agile process, including software requirement and design [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
Advances in intelligent techniques, such as natural language processing (NLP), have accelerated
the adoption of intelligent techniques in requirements engineering [
        <xref ref-type="bibr" rid="ref10 ref9">9, 10</xref>
        ].
      </p>
      <p>
        The potential of ISE, however, has not been realized to assist privacy engineering in ASD.
The empirical research on agile teams found that they prefer to be assisted with techniques and
tools to perform privacy requirement elicitation [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. They also get some dificulties in capturing
privacy aspects in textual user stories [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. There is a clear opportunity to bridge the gap between
the advancement of IS techniques such as NLP with privacy requirement engineering [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. We
hypothesize that IS-enabled tools will be able to overcome these challenges. To the best of
our knowledge, there is still a lack of research that sees the implementation of IS in privacy
engineering.
      </p>
    </sec>
    <sec id="sec-2">
      <title>2. Problem Statement</title>
      <p>
        The privacy engineering aspect of this research is focused on the requirement and design
phases. Several methodologies exist to elicit privacy requirements, including threat modeling
and privacy impact assessment. However, as indicated in the introduction, agile teams continue
to face challenges with incorporating this into the development process [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ]. Therefore, we
intend to build an intelligent system (IS) that is able to assist agile teams in privacy requirements
and design activities. We begin our research by investigating how IS might be used to help
the requirement and design phases of agile privacy engineering. This includes identifying
the current practice of privacy requirements and design engineering, as well as the kind of
intelligent techniques suitable for supporting it.
      </p>
      <p>
        Obtaining privacy requirements typically requires following several steps, such as identifying
assets, identifying personal data, modeling the system, analyzing data flow, identifying threats,
and eliciting requirements according to specific privacy principles. The amount of work required
for some of these processes is considered a challenge by some software teams [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. Once the
privacy requirements are defined, it can be dificult for software teams to choose from a
number of design patterns or privacy enhancement technologies (PET) in order to meet the
requirements. An empirical evaluation of our IS technique must be performed to demonstrate
the methodology’s rigor. The intelligent technique that we will implement must meet specific
criteria, such as recall [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], so that it can be used to support agile teams.
      </p>
    </sec>
    <sec id="sec-3">
      <title>3. Relevance</title>
      <p>
        The efort to integrate privacy in the software development process has been studied by providing
frameworks and methodologies. One of the most popular research to treat privacy is the risk
management approach. However, the practice of risk management is still conducted in a
traditional plan-driven way [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. The approach to address privacy in the ASD context has been
made in a limited amount of research [
        <xref ref-type="bibr" rid="ref14 ref7">14, 7</xref>
        ]. PRIPARE project has provided a handbook for
applying privacy by design to ASD [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ], while OASIS projects focus on the documentation [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ].
PRIPARE project proposes incremental privacy and security, sprint zero, and privacy security
sprints, while OASIS project mentions applying proactive and iterative, which derived the first
principle of the original privacy by design.
      </p>
      <p>
        Privacy is considered to be closely linked to security and risk management in software
systems [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ]. The research by Dam et al. [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] tries to automatically inspect code vulnerabilities
to reduce the risk of security infringement. They use a deep learning model called Long Short
Term Memory (LSTM) to learn the semantic and syntactic representation of the code that can
lead to vulnerabilities. The use of the deep learning model has been shown to outperform the
previous approach for some intelligent system tasks.
      </p>
      <p>
        The potential for automating the privacy process has been studied in several research [
        <xref ref-type="bibr" rid="ref11 ref18">18, 11</xref>
        ].
Study by Zimmermann [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ] identifies the potential of automation in a privacy engineering
context, especially the privacy impact assessment process. They argued that automatic selection
of privacy patterns for a given set of specifications is advantageous to the privacy engineer.
Aberkanne [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ] explicitly mentions the potential use of the Natural Language Processing model
to support the privacy requirement engineering. Utilizing the reusable elements [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ] from
design patterns, techniques, methods or tools can help achieve this goal. Design patterns
claimed to play an important role on enabling adaptation to privacy compliance [
        <xref ref-type="bibr" rid="ref20">20</xref>
        ]. However,
software practitioners still had dificulties connecting the requirement of regulation with a
suitable technical measure such as design pattern [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ]. Recommendation systems ought to be
the solution to the array of choices in the design pattern. Semi-automation approach through
an online questionnaire or wizard has been studied and implemented by Colesky et al. [
        <xref ref-type="bibr" rid="ref22">22</xref>
        ]
to get a suitable privacy design pattern based on the knowledge base [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]. Nevertheless, an
integrated solution that streamlines assets, data flow, and privacy requirements while providing
an appropriate privacy design pattern can be beneficial.
      </p>
      <p>
        Incorporating intelligent systems to ASD has been studied comprehensively in a systematic
literature review conducted by Perkusich [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ]. Most of these techniques are applied to support
the management of ASD, such as improving the estimation of efort and delay risk prediction
[
        <xref ref-type="bibr" rid="ref24">24</xref>
        ]. Intelligent systems also impact the other areas of ASD, such as software requirements,
software design, software quality, and testing with a lesser amount of study. Regarding security
in ASD, only one study uses fuzzy logic to combine security activities with ASD [
        <xref ref-type="bibr" rid="ref25">25</xref>
        ]. In a more
recent research, Villazimar [26] uses NLP to match a text feature from a user story with security
properties and security requirements. However, a specific study on applying the intelligent
system to privacy in ASD is not mentioned in the study [
        <xref ref-type="bibr" rid="ref8">8</xref>
        ].
      </p>
    </sec>
    <sec id="sec-4">
      <title>4. Research Method</title>
      <p>This research’s main objective is to provide an intelligent system to help the agile team integrate
privacy aspects into their software system. Tool support would be necessary to allow an easy
adaptation for agile teams. Therefore, we took the design science research framework, which
aims to create new and innovative artifacts [27]. Along with the design science research, we
aim to use the experimental design [28] method to measure our objectives. We plan to answer
the first problem in several cycles, which targets the requirement and design phase in privacy
engineering. In each cycle, an evaluation will be conducted to ensure the rigor of the proposed
artifact.</p>
      <p>
        We propose an Intelligent System (IS) concept to support decision-making on privacy
requirements by utilizing the reusable knowledge from privacy framework, privacy patterns, and
legal requirements. Privacy as one of the requirements in software development already has an
abundance of reusable knowledge [
        <xref ref-type="bibr" rid="ref19">19</xref>
        ]. Tools that can assist requirement analyst in managing
the requirement is needed. Connecting IS with reusable privacy knowledge is the focus of the
proposed approach. The IS is in the form of (1) Personal data identification from user stories, (2)
Automatic Data Flow Diagram Generation, (3) Privacy requirement recommendation systems,
and (4) Privacy design pattern recommendation system.
      </p>
      <p>The success of the proposed approach will be measured through experimental design. The
system performance for automatic privacy entities detection, automatic data flow diagram
generation, privacy requirement recommendation, and design recommendation system will be
evaluated using precision, recall, and F-Measure. We will perform a controlled experiment on
the requirement and design phase to compare the speed, leanness, and learning when intelligent
systems are incorporated to build privacy-aware software systems.</p>
    </sec>
    <sec id="sec-5">
      <title>5. Towards An Intelligence Systems Approach</title>
      <p>Our solution centered around the user stories as the primary input. Thus, we mainly use the
Natural Language Processing (NLP) methods to identify the needs of privacy requirements. The
ifnal output is a set of privacy requirements and design recommendations to support privacy
integration into software under development. We aim to reduce the manual efort on the privacy
engineering process by assisting it with some automatic approaches.</p>
      <p>The first module detects the personal data attributes in the user story using Named Entity
Recognition (NER). This becomes the basis for the generation of Privacy-Aware Data Flow
Diagram (DFD). The technical measure or solution for privacy requirements can be derived
from mapping the DFD elements with the privacy-enhancing technologies (PET) and privacy
patterns. LINDDUN [29] has provided the mapping from privacy requirement to the suggested
technical solution in the form of PET. In terms of privacy patterns, a well-documented catalog
is already established in privacypattern.org. Our work will combine the previously known
knowledge base to recommend a suitable technical solution. Our approach tries to minimize
the presents of data privacy experts or prior knowledge about privacy. The recommendation
system will use a content-based recommendation system based on the similarity between the
requirement and the description of PET and the Privacy Pattern. In addition, we will also use
the knowledge-based recommendation system in the form ontology-based recommendation
system and constraint-based recommendation system.</p>
    </sec>
    <sec id="sec-6">
      <title>6. Novelty</title>
      <p>
        Integrating privacy into agile software development is still an open problem. According to
Aberkanne, the use of NLP can become a potential solution for automating some processes
in GDPR compliance [
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. We aim to solve this gap by proposing IS approaches such as NLP
and recommendation systems targeting privacy engineering activities, which are requirement
generation and threat modeling [
        <xref ref-type="bibr" rid="ref3">3, 30</xref>
        ]. Additionally, we hope to streamline the privacy
requirement into a usable design pattern through the use of a knowledge base. We build the IS artifact
using a design science framework. Lastly, we intend to conduct a novel evaluation that assesses
our IS adaptation using experimental design [28].
      </p>
    </sec>
    <sec id="sec-7">
      <title>7. Progress</title>
      <p>The first phase of our research is to obtain knowledge bases (KB) to support the information
systems artifacts that we will build. We intend to use publicly accessible knowledge, including
frameworks, instruments, methods, dictionaries, and data sets. We divide the initial phase into
four iterations.</p>
      <p>The first iteration is dedicated to developing the knowledge base for the NER module. We
identify personal data by referencing dictionaries ofered by Data Privacy Vocabulary teams.
Additionally, we are developing our annotation data set to recognize data subjects and process
entities in user stories. Based on this knowledge base, we create our first information system
artifact powered by a state-of-the-art machine learning model for NER. This article was published
in ESPRE 2021 [31]. The second iteration will utilize the NER module to create a Privacy-Aware
Data Flow Diagram (DFD). We use publicly available tools to generate the relationship between
entities in a collection of user stories. We conducted a preliminary assessment and will publish
our research preview in the REFSQ 2022. In the future, we intend to perform additional
evaluations. The third and fourth iterations will develop an information system model to
support privacy requirements and design recommendations. These third and fourth iterations
are a work in progress.</p>
      <p>Our second phase of research will determine the influence of our privacy engineering approach
on ASD, particularly in terms of agility degree. Since we believe that this type of empirical
evaluation is new to agile privacy engineering, we would like to leverage the knowledge and
insights of the doctoral symposium community regarding this evaluation.</p>
    </sec>
    <sec id="sec-8">
      <title>8. Conclusions</title>
      <p>The purpose of this proposal is to establish a research agenda for incorporating privacy into
agile software development methodologies through the use of an intelligent system. We ofer a
novel perspective on the ISE model’s privacy requirements and design phases. Our primary
objective is to create an artifact that enables agile teams to rapidly meet desirable privacy and
design recommendations. We also aim to streamline the requirement into the correct privacy
design pattern. We hope this research will have an impact to provide a solution to overcome
the challenge of integrating privacy into the agile software development process.</p>
    </sec>
    <sec id="sec-9">
      <title>9. Acknowledgments</title>
      <p>The author acknowledge the scholarship granted by the Indonesia Endowment Fund for
Education (IEFE/LPDP), Ministry of Finance, Republic of Indonesia and the support received from the
University of Vienna, Faculty of Computer Science.
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