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  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>A Pattern Catalog for GDPR Compliant Data Protection</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Dominik Huth</string-name>
          <email>dominik.huth@tum.de</email>
          <xref ref-type="aff" rid="aff0">0</xref>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Chair of Software Engineering for Business Information Systems Fakultat fur Informatik Technische Universitat Munchen Boltzmannstr.</institution>
          <addr-line>3, 85748 Garching</addr-line>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Problem De nition</institution>
        </aff>
      </contrib-group>
      <fpage>34</fpage>
      <lpage>40</lpage>
      <abstract>
        <p>Today's digital Business Models challenge the concept of privacy of the previous century. As a legislative approach to keep up with the rapid technological change, the European Union has passed the General Data Protection Regulation (GDPR), which will be e ective in May 2018. For companies, this implies extensive changes in established processes and new organizational duties. With this work, we aim to develop an understanding and concepts that support an organization - consisting of people, processes and IT systems - in the implementation of privacy regulation. The central result will be patterns, i.e. observed successful approaches of how to address speci c requirements of the GDPR.</p>
      </abstract>
      <kwd-group>
        <kwd>Personal Data</kwd>
        <kwd>Data Privacy</kwd>
        <kwd>GDPR</kwd>
        <kwd>Privacy Engineering</kwd>
        <kwd>Dependency Model</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>-</title>
      <p>
        markets without regulation can fail and produce non-optimal outcomes. In [
        <xref ref-type="bibr" rid="ref14">14</xref>
        ]
we analyze the market for personal mobility data and alternative business models
to handle personal data, but still many of today's business models rely on the
exchange of free services for broad rights to data that is generated by the user.
Another initial nucleus could be the personal motivation of users to protect
privacy, but [
        <xref ref-type="bibr" rid="ref9">9</xref>
        ] and [
        <xref ref-type="bibr" rid="ref15">15</xref>
        ] suggest that individuals do not necessarily know how
to value their privacy and are not willing to pay for privacy.
      </p>
      <p>
        As an approach to address data privacy from a legislative perspective, the
European Union (EU) adopted the General Data Protection Regulation
(Regulation 2016/679, GDPR) in April 2016 [
        <xref ref-type="bibr" rid="ref6">6</xref>
        ]. It was passed after thorough
consideration and includes 99 articles and 173 recitals that guide the articles. As a
major change, failure to comply with the regulation can be ned with up to four
percent of an organization's revenue. This underlines the importance of clearly
understanding the requirements, analyzing the status quo of data protection
measures, deriving an action plan and implementing the necessary technical and
organizational measures to attain compliance with the GDPR. Thus, we set the
research goal of this project:
      </p>
      <p>Research Goal: To support the adaptation of privacy legislation in
organizations, consisting of people, processes and IT systems.
2</p>
    </sec>
    <sec id="sec-2">
      <title>Related Work</title>
      <p>
        For addressing the set research goal, we will rst refer to our concept of an
Enterprise Model and then analyze existing work using the established Enterprise
Model in order to categorize the existing work and determine which of the
aspects of the model it addresses. We rely on a simpli ed Enterprise Architecture
model based on [
        <xref ref-type="bibr" rid="ref4">4</xref>
        ] and only consider the three layers Business &amp; Organization,
Application &amp; Information and Infrastructure. Figure 1 locates the presented
work within this Enterprise Architecture model.
      </p>
      <p>
        Legal advice gives an abstract view of the challenges to be addressed.
According to [
        <xref ref-type="bibr" rid="ref12">12</xref>
        ], these are the principle of accountability, the creation of records
of processing activities, the execution of data protection impact assessments, the
implementation of technical measures for protection, the extension of data
subject rights and the installation of the role of data protection o cer (DPO). [
        <xref ref-type="bibr" rid="ref21">21</xref>
        ]
analyses the regulation and compares it in detail to Directive 95/46/EC, which
it repeals when entering into force. The resulting practical implications are the
obligation to specify data needs and usage, to consider conditions for data
processing in an international context, to build privacy through data protection by
design and default, to demonstrate compliance, to develop processes for dealing
with data breaches, to consider possible sanctions when acting, to designate a
DPO, to establish processes for providing information to and getting consent
from data subjects, to create ways of deleting or transferring an individual's
data and to document processing activities.
      </p>
      <p>
        The paradigm of Privacy by Design was keyed by the Canadian Information
Commissioner [
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] and encompasses the notion of building privacy into IT systems
and processes, but also physical designs. However, the seven proposed principles
are rather a goal de nition than an instruction of how to implement privacy
[
        <xref ref-type="bibr" rid="ref19">19</xref>
        ] and a translation of these principles into system requirements is necessary
[
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. Nonetheless, there are also critical voices who claim that "privacy cannot
be hardcoded" [
        <xref ref-type="bibr" rid="ref16">16</xref>
        ].
      </p>
      <p>
        Method engineering, according to [
        <xref ref-type="bibr" rid="ref1">1</xref>
        ], is the discipline of creating methods
that support the development of Information Systems and can be compared to
Software Engineering for the development of software. When adapting a method
for a speci c situation and combining individual elements, so-called method
chunks, it is called a situational method [
        <xref ref-type="bibr" rid="ref13">13</xref>
        ]. An application to the domain
of governance, risk and compliance can be found in [
        <xref ref-type="bibr" rid="ref7">7</xref>
        ], where method fragments
are categorized into ve dimensions (conceptual, strategic, organizational,
technical, cultural) and assigned to di erent roles within the enterprise. A recent
development is the eld of Privacy Engineering [
        <xref ref-type="bibr" rid="ref10">10</xref>
        ], which systematically
addresses privacy issues during system development.
      </p>
      <p>
        A notable method for modeling privacy threats is LINDDUN [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ], [
        <xref ref-type="bibr" rid="ref24">24</xref>
        ]. It is
intended to support software developers in identifying and addressing privacy
threats early during software development. An extensive privacy threat tree [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]
addresses all the security threats that are included in the acronym and gives
guidance to software developers.
      </p>
      <p>
        The operationalization of Privacy and Security by Design was the subject of
study of the EU project PRIPARE (Preparing Industry to Privacy-by-design by
supporting its Application in Research) [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ], which we consider to cover all three
layers of the model presented earlier. The main results include a process to
address the accountability postulate of the GDPR and so-called patterns for privacy
preserving development of software. They distinguish between risk-based (such
as LINDDUN, [
        <xref ref-type="bibr" rid="ref23">23</xref>
        ]) and goal-oriented approaches, such as the GDPR, which
have to be broken down into smaller requirements. These two approaches are
considered to be complimentary, with application of the goal-oriented principle
rst and detailed system analysis second [
        <xref ref-type="bibr" rid="ref18">18</xref>
        ].
      </p>
      <p>
        Patterns are observed solutions for a given problem [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] that have emerged
in three independent instances. Historically, they originate from the domain
of software architecture, but have also been applied in Enterprise Architecture
Management, a holistic approach to align business and IT [
        <xref ref-type="bibr" rid="ref2">2</xref>
        ]. They describe
the solution with consequences, known uses, actors and related patterns [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. The
PRIPARE project also created a pattern catalog [
        <xref ref-type="bibr" rid="ref17">17</xref>
        ] that includes 26 privacy
patterns at a technological level.
      </p>
      <p>The gap we identify is the consideration of holistic patterns that are
specifically targeted at compliance with the new GDPR regulation. As it has been
passed in 2016 and becomes e ective in 2018, there are currently industry
efforts under way who aim at achieving compliance by the time the GDPR
becomes e ective. These e orts have not been investigated so far and have not
been analyzed with regards to the existing body of knowledge.
3</p>
    </sec>
    <sec id="sec-3">
      <title>Proposed Approach</title>
      <p>
        The goal of this research project is to support the practical application of privacy
patterns by developing theory and insight from the current industry e orts.
An approach that was designed to ensure theoretical contributions of industry
cooperation projects is pattern-based design research [
        <xref ref-type="bibr" rid="ref3">3</xref>
        ]. It combines the use
of patterns, design theory and the concept of a design theory nexus to propose
a four-step process (as depicted in gure 2) consisting of the steps observe &amp;
conceptualize, pattern-based theory building, solution design and application and
evaluation and learning.
      </p>
      <p>The EU GDPR is not the rst privacy regulation that organizations have
to become compliant to. In fact, it repeals EU directive 95/46/EC, which was
the basis for prior national privacy legislation. Researchers have addressed these
concerns with threat frameworks and situational methods before. There are also
similar legislation that requires action within the organization and has been
researched before, such as nancial or risk regulation. To develop a clear
understanding of the existing work and to be able to concisely identify the di erences
that are invoked speci cally by the GDPR, we derive the rst research question:
RQ1: Which conceptual frameworks exist that can be instrumented to
describe regulatory requirements and the design of possible solutions?
The GDPR as a whole consists of 99 articles, some of which de ning terms,
some concerning administrative acts regarding the regulation, and some
introducing rights for data subjects and obligations for the data controllers and
processors. These have to be extracted from the legal text and formalized as
elementary requirements. Each of the requirements can then be addressed by
methods or techniques that are investigated at a later stage. Thus, we formulate
the second research question:</p>
      <p>RQ2: What are the elementary requirements of the GDPR and how can
they be modeled with the existing concepts?</p>
      <p>Since the GDPR is applicable from 2018, there are currently ongoing e orts
in organizations with the goal to prepare for the legislation and to implement
the required measures, such as the establishment of a data protection o cer. It
is necessary to observe and describe these e orts and to classify the approaches.
Who is responsible? Who is in charge of planning, who is in charge of execution?
How are the requirements identi ed, how are project goals set, which processes
are established? Which tools or methods are used to support this e ort? In short,
we state the third research question as:</p>
      <p>RQ3: What is the state of the practice in the implementation of GDPR
requirements in Germany and how does the practice instrument
theoretical knowledge?</p>
      <p>From these practical investigations, we aim to identify common observations
from various industry partners. These so-called pattern candidates have to be
consolidated into patterns and described using the theoretical background that
was identi ed before. It will be analyzed how successful the application of each
pattern has been, since commonality does not necessarily imply quality. As the
fourth research question, de ne:</p>
      <p>RQ4: Which successful patterns can be identi ed for ful lling the
elementary requirements of the GDPR?</p>
      <p>There might be di erent patterns that address the same elementary
requirement. At the same time, there might be patterns that require the application
of another pattern in order to be executed successfully. In the last step, we aim
to analyze dependencies among patterns. One such dependency could be the
reduced need for on site data security when transferring personal data to cloud
services, but a rigorous selection process for the cloud provider to comply with
the data security requirements. This leads to the last research question:
RQ5: How are solution options interrelated with each other? Which
solutions are independent, which require other actions, and which replace
other solution options?</p>
    </sec>
    <sec id="sec-4">
      <title>Acknowledgment</title>
      <p>This dissertation project is supervised by Prof. Dr. Florian Matthes at the chair
for Software Engineering for Business Information Systems, TU Munchen. It is
part of the TUM Living Lab Connected Mobility (TUM LLCM) project and has
been funded by the Bavarian Ministry of Economic A airs and Media, Energy
and Technology (StMWi) through the Center Digitisation.Bavaria, an initiative
of the Bavarian State Government.</p>
    </sec>
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