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<article xmlns:xlink="http://www.w3.org/1999/xlink">
  <front>
    <journal-meta />
    <article-meta>
      <title-group>
        <article-title>Atlas: the Enterprise Cartography Tool</article-title>
      </title-group>
      <contrib-group>
        <contrib contrib-type="author">
          <string-name>Pedro Sousa</string-name>
          <email>pedro.manuel.sousa@tecnico.ulisboa.pt</email>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Ricardo Leal</string-name>
          <email>ricardo.leal@linkconsulting.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <contrib contrib-type="author">
          <string-name>Andre Sampaio</string-name>
          <email>andresampaio@linkconsulting.com</email>
          <xref ref-type="aff" rid="aff1">1</xref>
        </contrib>
        <aff id="aff0">
          <label>0</label>
          <institution>Instituto Superior Tecnico</institution>
          ,
          <addr-line>Av. Rovisco Pais, 1, 1049-001 Lisboa</addr-line>
          ,
          <country country="PT">Portugal</country>
        </aff>
        <aff id="aff1">
          <label>1</label>
          <institution>Link Consulting SA</institution>
          ,
          <addr-line>Av. Duque de Avila 23, 1000 Lisboa</addr-line>
          ,
          <country country="PT">Portugal</country>
        </aff>
      </contrib-group>
      <abstract>
        <p>The need to maintain architectural representations of enterprises is an indescribable fact nowadays given their constant need evolve. However, despite the large number of Enterprise Architecture tools available, enterprises are unable to maintain architectural models updated, given the e ort it entails. Atlas is an Enterprise Architecture tool conceived to reduce the e ort needed to keep architectural models updated, in enterprises where changes are constant and design occurs in a decentralized, distributed and asynchronous process using multiple design tools. Atlas uses Enterprise Cartography as the approach paradigm to be able to generate architectural views automatically from the models and information gathered from multiple sources, with a time bar allowing a seamless navigation in time, from past to future models.</p>
      </abstract>
      <kwd-group>
        <kwd>Enterprise Cartography</kwd>
        <kwd>EA</kwd>
        <kwd>Enterprise Architecture</kwd>
        <kwd>Architecture Visualization</kwd>
        <kwd>Architecture tools</kwd>
      </kwd-group>
    </article-meta>
  </front>
  <body>
    <sec id="sec-1">
      <title>1 Introduction</title>
      <p>
        The need to maintain explicit knowledge of the architecture of enterprises is an
indisputable fact nowadays given their constant need to evolve. Either for the
purpose of enterprise governance, engineering, compliance or maintenance,
architectural representations are an enterprise asset that must be governed[
        <xref ref-type="bibr" rid="ref1">1</xref>
        ]. By
explicit knowledge we consider both the existence of models of the Enterprise
Architecture, hereafter EA, kept in some repository as well as the capability to
present graphical representations of the enterprise artifacts and their
dependencies, also referred as architectural views[
        <xref ref-type="bibr" rid="ref2 ref3">2, 3</xref>
        ], here after referred as EA views for
space reasons.
      </p>
      <p>
        We refer to enterprises and not to organizations since the rst term has
a wider scope according to the the Open Group de nition were "enterprise is
any set of organizations that have a common set of goals "[
        <xref ref-type="bibr" rid="ref2">2</xref>
        ], and the approach
presented here applies to both. An example of an enterprise is the Portuguese
National Health System1, that includes more than one hundred health
organizations.
      </p>
      <sec id="sec-1-1">
        <title>1 Servio Nacional de Sade: https://www.sns.gov.pt</title>
        <p>
          We also consider a distinction between enterprise transformation and
evolution, the di erence being that the former is mostly related with top level
restructure and the later is related with the optimization of current state of
a airs[
          <xref ref-type="bibr" rid="ref4">4</xref>
          ]. Despite the di erences, they both require EA as input data and they
both causes changes in enterprise, thus likely induces changes in the EA. Here
after we use the term change initiatives to refer to both transformation and
evolution initiatives. Since change initiatives are temporary, unique and a
purposeful activity, they correspond to the concept of projects as de ned in the
project community[
          <xref ref-type="bibr" rid="ref5">5</xref>
          ].
        </p>
        <p>
          Stefan[
          <xref ref-type="bibr" rid="ref6">6</xref>
          ] presents a list of 28 EA application scenarios and the corresponding
literature sources, making clear importance of knowing the EA for enterprise
maintenance, planning and evolution. In its simpler and basic from, information
about EA boils down to the list of enterprise artifacts and their dependencies.
Given the variability and quality of existing EA tools and their representation
capabilities[
          <xref ref-type="bibr" rid="ref7">7</xref>
          ], one could argue that enterprises could easily create and maintain
an EA repository where all models are kept updated so that core enterprise
activities could bene t from such information[
          <xref ref-type="bibr" rid="ref6">6</xref>
          ].
        </p>
        <p>However, based on our experience of nearly two decades in organizations
from various countries and industry sectors, we found that this is not the case.
On the contrary, enterprises are far from being able to create and maintain an
EA repository updated, given the e ort that such endeavor would entail. We
believe that a signi cant part of such extra e ort results from the following
organizational aspects:
{ Enterprise evolution uses multiple "Enterprise Architecture" tools. Enterprise
evolution uses multiple tools for EA, being o ce tools commonly used ones.
Most of the times such tools are not integrated and do not provide coherent
information. For example, when the board of director of a company, acting
as an architect designing the company, decides to create a new department
they will not go to an EA tool to model the new department. Most likely, the
decision will appear the board meeting minutes (probably an o ce document)
a few weeks or months before the intended date. If the organization structure
is modeled in some EA tool, e ort is required to update it in conformity with
this new design. The person that performs such update in the EA tool is not
designing but merely updating the model and its architectural representations.
{ Enterprise evolution is mostly a distributed and asynchronous process.
Enterprise evolution is planned and designed by di erent units in an asynchronous
and distributed process, involving many actors and many dimensions of
concerns without formal mechanisms of communication between the di erent
designers. For example, when a director decides to make changes in their
department, it probably will conduct meetings with other departments to check
for possible dependencies and impacts. Directors of other departments can
do the same for their departments. Despite the number of face-to-face
meetings, there is no design process established so that the knowledge gathered in
such meetings is consolidated and shared across the enterprise, so that design
actually uses coherent and updated information.</p>
        <p>In such context, one can envisage the huge e ort required to update the
models in the EA tools used. The fastest the enterprise changes, the more e ort
is required to keep such models updated. When enterprises are already faced with
lack of resources for the day to day projects, they are not willing to allocate e ort
to keep enterprise models updated.</p>
        <p>But the problem is actually more complex because enterprises models are also
a moving target. In fact enterprises need models that refer to di erent points in
time, namely:
AS-WAS models. These models represent the enterprises past state of a airs,
including not only the past architecture but also the plans of change initiatives
of the past. They are most useful for auditing and accountability purposes
since they can hold justi cations for the decisions taken in the past. For
example, the decision took in the past to acquire development capacities on
some technology could be sustained on the plans of a change initiative to
build new products using that technology, regardless the fact of that change
was actually put forward or dismissed.</p>
        <p>AS-IS models. These models represent the current enterprise. AS-IS models are
required for current operations and for reacting to events.</p>
        <p>
          TO-BE models. These models represent the future enterprise, and are critical
for planning the next change initiatives, as recognized both by EA[
          <xref ref-type="bibr" rid="ref8 ref9">8, 9</xref>
          ] and
project management[
          <xref ref-type="bibr" rid="ref10 ref11">10, 11</xref>
          ] communities. In fact, to plan a project that
will start in 6 months, you need to know how the enterprise will be when
the project starts, not what it is today, as many changes can come in the
meantime.
        </p>
        <p>
          Naturally, AS-WAS models are just the old AS-IS and do not pose any
challenge. But AS-IS and TO-BE models are real challenges, since they must be
take into consideration the multiple ongoing change initiatives. This di culty has
a substantial impact on the ability to plan change initiatives and, consequently,
has an impact on the costs, time and risks of achieving their expected outcomes[
          <xref ref-type="bibr" rid="ref11 ref8">8,
11</xref>
          ].
        </p>
        <p>So, the focus of our research has been in nding a low e ort method that
allows enterprise to have updated AS-WAS, AS-IS and TO-BE models and EA
views. To keep architectural models and views updated, one needs to address two
main issues: (i) how to gather information about the changes in the enterprise
models and views and, (ii) how to update the architectural models and views
based on the gathered information. Again, our experience in actual companies
has shown us directions for such questions.
{ Gather information about the changes. Our nding is was that, in general, it
is easier to gather information about what people are currently doing than
about what they did in the past. Since what people are doing today is what
most likely will be enterprise TO-BE, this nding means that it is easier to
know the expected TO-BE than the AS-IS of the enterprise. So, since TO-BE
models will become AS-IS and AS-WAS, this nding tell us that the focus
should be target to TO-BE models.
{ Update EA views. Our nding is that hand-draw EA views will likely remain
obsolete much longer than generated views. Hand-draw models requires
placing symbols in a drawing canvas, where aesthetic aspects are one key concern
and time consuming factor. Therefore, to keep such views updated, one needs
both to update the contents as well as the aesthetic aspects. So, this nding
tell us to avoid hand-draw view and support only automatic generated views
from gathered models (information).</p>
        <p>Atlas2 was designed to explore the ndings presented above. It is an EA tool
conceived to reduce the e ort needed to keep EA views updated in enterprises
designed in a decentralized, distributed and asynchronous process using multiple
design tools. In Atlas, EA views are generated automatically and have a time
bar allowing a seamless navigation in time, from past to future state of each EA
view. Information about changes is gathered by the observation of the plans of
ongoing change initiatives.</p>
        <p>
          This approach was rst presented in[
          <xref ref-type="bibr" rid="ref12">12</xref>
          ], initial implementation was described
in [
          <xref ref-type="bibr" rid="ref13 ref14">13, 14</xref>
          ], and results from rst projects were presented in[
          <xref ref-type="bibr" rid="ref15 ref16">15, 16</xref>
          ]. The term
Enterprise Cartography was coined in[
          <xref ref-type="bibr" rid="ref17">17</xref>
          ]. In the next section we present the
concept of Enterprise Cartography, and then we present relevant aspects of the
Atlas tool in supporting the above ideas.
        </p>
      </sec>
    </sec>
    <sec id="sec-2">
      <title>2 Enterprise Cartography</title>
      <p>Simply put, EC is the process of abstracting, collecting, structuring and
representing architectural artifacts and their relations from the observation of
enterprise reality. The expression "enterprise reality" refers to the present state
of the enterprise. Traditionally, the observation of this reality is a subjective
perception of an observer, and consequently it is probable that there are di
erent actors that perceive di erent realities of the same enterprise. However, as
we propose and will become clear along the text, the perception of the present
state of the enterprise (the reality) is sustained on relevant facts captured in logs
and models, and represented through artifacts based on previously de ned and
agreed upon models.</p>
      <p>
        We refer to "architectural artifacts" as the enterprise's observable elements
whose inter-dependencies and intra-dependencies express the architecture of the
enterprise. Naturally, di erent institutions may consider various sets of artifacts
as part of their architecture. To abstract, structure and represent the architecture
related artifacts, one needs the whole set of knowledge and concepts implied
in architecture visualization and representation. For example, the concepts of
semiotic triangle[
        <xref ref-type="bibr" rid="ref18 ref19">18, 19</xref>
        ], the model of architecture description presented in ISO
IEEE 1471[
        <xref ref-type="bibr" rid="ref3">3</xref>
        ] and a symbolic notation, such as the one used in ArchiMate[
        <xref ref-type="bibr" rid="ref20">20</xref>
        ],
are concepts necessary to the production of EA views.
      </p>
      <p>Ongoing change initiatives and their plans are an essential part of enterprise
reality because they de ne the near future TO-BE of the enterprise if no further</p>
      <sec id="sec-2-1">
        <title>2 www.linkconsulting.com/atlas</title>
        <p>decisions are taken that might have an impact on them. This is a fundamental
concept that we call emerging AS-IS, which we de ne as the state of the
enterprise after successful completion of ongoing change initiatives. This corresponds
to the inertia of a body; if no contrary action is taken, inertia determines the
body future position and speed. Similarly, if no opposite actions are done,
ongoing initiatives determine the future of the institution and thus the TO-BE of
models and architecture.</p>
        <p>Given that in today enterprises, change initiatives are omnipresent, the
concept of Emerging AS-IS is not only an essential capacity for the planning of
new change initiatives, but also for the monitoring of the enactments of ongoing
change initiatives. When driving a car the faster the car is moving, the farther
ahead one should focus our eyes to match the longer time and distance context
within which we need to steer it. Likewise, when steering an enterprise, the faster
the enterprise is changing, the more important is to know the emerging AS-IS,
as time ows.</p>
        <p>
          Enterprise cartography is a purely descriptive perspective, since it does not
explicitly incorporate the purposeful design of the new enterprise artifacts, as
one expects in EA. Such a di erence is also evident in the de nitions of the
architect and cartographer roles. According to the IEEE Standard Glossary of
Software Engineering Terminology[
          <xref ref-type="bibr" rid="ref21">21</xref>
          ], the term architect is de ned as "The
person, team, or organization responsible for designing systems architecture",
and in the Merriam-Webster dictionary[
          <xref ref-type="bibr" rid="ref22">22</xref>
          ], the term cartographer is de ned as
the person who makes maps. So, an architect is essentially a person that designs
and shapes intended changes to the architecture of the present enterprise reality,
while a cartographer is essentially a person that aims at representing reality as
it happens, including such changes as they are occurring.
        </p>
        <sec id="sec-2-1-1">
          <title>2.1 Enterprise Cartography Principles</title>
        </sec>
        <sec id="sec-2-1-2">
          <title>Principle 1: Change initiatives are enterprise artifacts.</title>
          <p>
            A change initiative is an enterprise artifact. This statement is in line with
most architecture guidelines such as the Work Package concept in both
TOGAF[
            <xref ref-type="bibr" rid="ref2">2</xref>
            ] and ArchiMate[
            <xref ref-type="bibr" rid="ref20">20</xref>
            ]. However, we go further and also state that
their plans can be observed as part of the enterprise AS-IS models. We
assume that change initiatives have plans because they purposefully aim at
some desire goals and therefore should have plans to achieve them.
Furthermore, these plans and goals includes TO-BE models of the enterprise .
          </p>
        </sec>
        <sec id="sec-2-1-3">
          <title>Principle 2: Changes in the set of productive artifacts are planned ones.</title>
          <p>This principle states that artifacts do not become productive or
nonproductive randomly, but only as a result of change initiative. Since change
initiatives are also enterprise artifacts (principle 1), an artifact becomes
productive or non-productive only by the action of another productive artifact
(the change initiative). Notice that the assumption that ongoing change
initiatives are productive artifacts, is sustained by the purposefulness aspect of
the change initiative, by which the enterprise becomes more valuable after
the purposeful changes than before.</p>
        </sec>
        <sec id="sec-2-1-4">
          <title>Principle 3: All enterprise artifacts have a ve-state life-cycle: conceived, gestating, alive, retired and removed.</title>
          <p>
            Despite the fact that common EA notations (e.g.[
            <xref ref-type="bibr" rid="ref20">20</xref>
            ] do not formalize
artifacts states, it is many convenient to have models that mix existing and
not existing artifacts, to express model changes. In this principle we say
that existing artifacts with an enterprise do not "fell from the sky", but go
through an evolution process instead. Let us rst consider as productive the
artifacts as the ones that are somehow involved in the enterprise business
processes that produces values. In gure 1 we present these ve states, their
fundamental transitions and there classi cation with productiveness: Non
Productive Yet , Productive and No Longer Productive states.
{ Conceived state, as the rst state of existence. It corresponds to a state
where the artifact is planned but its materialization into a productive
artifact did not started yet. A conceived artifact is an idea that exists
TO-BE models (or plans) of some change initiative, even if itself is still in
the conceived state.
{ Gestating is the state when an artifact is being constructed or acquired
to become productive. As conceived artifacts, gestating ones do not play
a role in the enterprise transactions and processes. This state only di
erentiates from the conceived state by the fact that the change initiative
that aims at putting the artifact into production has already started. An
ongoing change initiative is necessarily a productive artifact, since it can
have an impact on other productive artifacts and is expected to produce
value after its completion.
{ Alive. An alive artifact plays purposeful roles in the enterprise to create
value. Conceived and Gestation artifacts might have an relationship on
life objects, namely in the ones that are conceiving or creating them. But
their relation is a passive one, not a purposeful role as alive objects must
have to create value. From Principle 2, it is clear that an artifact cannot
be brought into existence as alive; it always exists rst as conceived before
being alive.
          </p>
          <p>Notice that in this paper we only consider Alive as the only productive
state. However, one can consider other productive states, such as for
example the Deprecated state. However, it is not relevant for the purpose of
this paper and we continue with the case of alive as the only productive
state.
{ Retired 3. is when an alive artifact no longer plays a role in the enterprise
transactions and processes to create value. As in the conceived and
gestation states, a Retired artifact may still have an impact on alive artifacts.
In fact, even if it does not create behavior or value to the enterprise, it
may be the target of several housekeeping activities that are necessary
after being dead.</p>
          <p>The dead state can be achieved directly after gestating state, without
becoming alive. An artifact planned to become alive by a given change
initiative might never be alive either because the initiative was canceled
or because it simply changed plans and decided to no longer put that
artifact into production.
{ Removed. Represents the post-Retired state where the artifact has no
impact in the remaining artifacts. A removed artifact is unable to interact
with alive enterprise artifacts. An artifact can move from conception
directly to removal when it never materialized in a gestation, meaning that
it never went beyond an idea.</p>
        </sec>
        <sec id="sec-2-1-5">
          <title>Principle 4: The TO-BE state precedes the AS-IS state.</title>
          <p>This principle states that productive artifacts in the AS-IS model existed
before in the TO-BE models of some changing initiative. Furthermore, such
models were part of the enterprise observed AS-IS at some point in time
prior to the current time.</p>
        </sec>
        <sec id="sec-2-1-6">
          <title>Principle 5: The emerging AS-IS can be inferred by observing the AS</title>
        </sec>
        <sec id="sec-2-1-7">
          <title>IS of an enterprise.</title>
          <p>The emerging AS-IS state di ers from the AS-IS state by the artifacts
planned to be brought into production/retirement by ongoing change
initiatives. Since ongoing initiatives are alive artifacts, their plans (TO-BE
models) are in the scope of the cartographer observations of the enterprise
reality.</p>
          <p>
            Therefore, one can foresee the set of productive artifacts at some point in
time in the future by consolidating the AS-IS with the TO-BE models of
the ongoing change initiative whose completion date precedes the desired
moment in time[
            <xref ref-type="bibr" rid="ref12">12</xref>
            ]. This can be stated as:
          </p>
          <p>P (tm) = P (t0) [ N Y P (CItn ) n N LP (CItn )8t0
tn
tm
(1)
Where P (t) represents Productive artifacts at time t, N Y P (CIt) and N LP (CIt)
represents respectively Not Yet Productive and Not Longer Productive
artifacts in plans of Change initiatives that produces results at time t.</p>
        </sec>
      </sec>
      <sec id="sec-2-2">
        <title>3 In previous publications the Retired stated was named as Dead.</title>
      </sec>
    </sec>
    <sec id="sec-3">
      <title>3 Atlas Overview</title>
      <p>Altas is a web based EA tool providing all functionality one could expect from
such a tool. It allows the full con guration of the meta model, i.e. the classes and
references types whose instances are used to express models of the organization.
Users can also con gure in and out data both in format as well in contents for
integration with other tools and systems.</p>
      <p>Atlas supports custom con gured user interfaces. Given the wide scope of
usage of EA tools within organizations, it will likely be used by employees without
basic modeling concepts. So, besides allowing the con guration of elements in
Atlas default interfaces (e.g, tabs in object edition properties), it allows users to
con gure speci c forms, where users only see the desired properties, even if they
are from di erent objects. Atlas also provides analytic elements such as charts,
dashboards and EA views that we called blueprints.</p>
      <p>Atlas also supports the con guration of behavior associated with EA views,
validation rules, state propagation between objects in the repository, among
others. Such behavior can be stated both in queries and rules that run directly
on the selected repository as well as in jobs and batch's that run on a dedicated
sandboxes.</p>
      <p>We now focus the description of how Atlas supports enterprise cartography.
A typical scenario is presented in gure 2 where information from several sources,
including o ce tools, is processed and feeds the generation of AS-WAS, AS-IS
and TO-BE EA views and analysis. In this scenario, enterprise artifacts and
their relationships exist in multiples sources, and each source will likely have its
own meta model. Furthermore, information in each source may be related with
the past, present or future of EA.</p>
      <sec id="sec-3-1">
        <title>3.1 Model transformation</title>
        <p>
          Model transformation occurs whenever data ows between sources with di erent
meta models, as is the case when Atlas gathers information from other sources,
and has been a relevant topic in software development and integration[
          <xref ref-type="bibr" rid="ref23">23</xref>
          ].
Among the di erent technologies to handle model transformation[
          <xref ref-type="bibr" rid="ref23">23</xref>
          ], in
Atlas we adopted a two step approach, each with its own technology. The rst step
deals with the format transformation and is based on XSLT[
          <xref ref-type="bibr" rid="ref24">24</xref>
          ] which is very
common and convenient for processing XML les. The second step deals with
the actual model transformation, and uses a high level type-based rules that
operates on types, instances and relationships.
        </p>
        <p>
          Consider the case where one wants to import a BPMN[
          <xref ref-type="bibr" rid="ref25">25</xref>
          ] model and that
Data Stores must be imported as Applications in the Atlas repository. To
congure such rule, one assigns a batch to the desired source or le extension and
then de nes three jobs. The rst job is con gured with the XSLT script that
converts the BPMN tool format into Atlas XML format. The second job is
congured with text le script with the transformation rules, that transforms the
source model and objects into Atlas model and objects. Finally the third job
imports the transformed objects into the Atlas repository. In the example given,
the transformation rules script is a "rename data type Data Store to
Application". The names of the Data Stores in the BPMN model are matched against
Applications in the Atlas repository, and unmatched Data Stores will yield the
creation of new Applications, as discussed in the next section.
        </p>
        <p>If several batchs are assigned to the same source or le extension, the user
is requested to select one to upload the le. This is a very useful feature since
within the same enterprise, di erent teams or departments may use the same
notation di erently and di erent rules might be required.</p>
        <p>Another rather important aspect is to be able to perform di erent a behaviour
in case of the imported artifacts match with objects that already exist in the
Atlas repository or if new objects were created during the importation. The
rules allows the importation behaviour to be dependent of any state in the Atlas
repository, but the match for existing objects is done solely on the object names,
as discussed next.</p>
      </sec>
      <sec id="sec-3-2">
        <title>3.2 Object Names</title>
        <p>In the scenario presented in gure 2 one needs to establish a mechanism to
match objects existing in di erent sources that correspond to the same enterprise
artifact. In other words, one needs an identi cation mechanism valid throughout
the di erent sources to match imported objects against the ones that already
exist in the Atlas repository.</p>
        <p>The use of 128 bits Object Identi ers (OIDs, also known as UUIDs) ensures
uniqueness for most practical purposes even when generated by di erent and
independent tools. However, these system-generated OIDs are not useful in the
scenario presented in gure 2, since the same enterprise artifact would have
objects with a di erent OID in each source.</p>
        <p>Change is also a factor against the use of OIDs. Consider that a process
modeling tool holds a model of the sales process in which the CRM application
is used to inquire the status of the client payments. Later, the process changes
and instead of using the application CRM, it now uses the application ERP for
the same purpose. This change can be done simply by change the application
name, from CRM to ERP. However, in this case, the name has change but the
OID in the process modeling tool is the same, despite the enterprise artifact
has changed. This leads to a situation where the same object now referrers to
a di erent enterprise artifacts, breaking the existing biding between OIDs and
enterprise artifacts even in the context a single tool.</p>
        <p>
          User de ned object names can easy the task of matching objects between
sources, if object names correspond to the names of the artifacts have in the
enterprise. However, in most cases, object names are used de ned and normally
are not unique, since uniqueness is assured by OIDs. In Atlas, we took a di
erent approach where identi cation and denotation is established by user de ned
object names[
          <xref ref-type="bibr" rid="ref26">26</xref>
          ] and OIDs are not disclosed to user, except for audit traces.
This approach implies that, from the user perspective, objects of the same class
cannot have the same name.
        </p>
        <p>In practice this can be a strong restriction in large enterprises where one
could expect to have several organizations with di erent business processes or
actors with the same name. For example, in the case of Portuguese National
Health System, one could expect to have Actors with the same name in di erent
hospitals. To support this scenario, users can de ne composite object names,
by selecting object properties to be used for its identi cation, as primary keys
in relational databases. In this case, the name of the object could be de ned
by both hospital and Actor names.Notice that users can change the name of
objects, given that they are object editable properties.</p>
        <p>Despite the fact that in most situations users deal with a at object name
space, full object names are unique URLs composed as follows:
serverURL/RepositoryName/ClassName/ArtifactNameField N. ..</p>
        <p>.ArtifactNameField 0.</p>
        <p>The concatenation of the elds ArtifactNameField N to ArtifactNameField 0
must be unique within the objects of the same ClassName. All els but the last
are optional (i.e can be null ), except the last one ( ArtifactNameField 0 ) that
cannot be null.</p>
      </sec>
      <sec id="sec-3-3">
        <title>3.3 Object State</title>
        <p>In Atlas, object state is de ned as a set of properties values, whose types are user
de ned. A time bar in the object edition interface allows users to visit properties
past states, up to the time of its creation. Basic types as Numeric, Text, Rich
Text, Hyperlink, Boolean are available. Users must de ne their own reference
types for reference properties</p>
        <p>Object properties do not change type (structure) over time, this means that,
for example, a numeric property cannot not become a reference property.
However, object sate, as a collection of properties, can change structure over time
since properties may be added or removed from its class over time as discussed
in the next section. Therefore, objects of the same class can have an entirely
di erent set of properties.</p>
        <p>References properties are assured to be either null or to refer to one or more
objects. There are no dangling references, since reference value assignment
triggers object creation and object deletions nullify references. In Atlas, object are
created when their names are registered thus, by assigning a new name (value)
to a reference properties a new object is created with that name. Such created
object has no state yet, only a name.</p>
        <p>By default reference properties have no state associated besides besides the
name of the denoted object. However, in some situations it is very convenient
to add properties to references. This is done by binding a class with a reference
property, whose structure becomes the structure of the class. Any class de ned
in the meta model can be bound to a reference property, and the same class can
be bounded to di erent reference properties.</p>
      </sec>
      <sec id="sec-3-4">
        <title>3.4 Meta model Co-Evolution</title>
        <p>As described earlier, classes also change over time whenever users remove or add
properties. By moving back the time bar in the class edition interface, one can
see the class properties at any point in time, up to time the class was created.
Property creation and removal does not a ect the state of the objects in the
repository. If a property is deleted from a class at a given time, it will no longer
be visible in the object's structure after that time, however, as soon as the time
bar goes back in time the deleted property will appear in object state history
with the corresponding values.</p>
        <p>
          Besides adding and removing properties, Atlas also provides support for
complex operations in meta-model and is able to propagate the necessary changes
to objects in the repository. For example, the Property to Class meta model
operation promotes a textual property to a reference property to a class created
from the original text property. An example could be promoting the Home
Address text property of a Client class into a reference property to a new class
Home Address, so that clients with the same address could share the same
object. A meta-model evolution primitive catalog, with primitives such as Flatten
Hierarchy, Merge Class, Split Class, Property to Class, Class to Property, among
others[
          <xref ref-type="bibr" rid="ref27 ref28">27, 28</xref>
          ] is available.
        </p>
        <p>
          These type of changes in the meta model requires the changes on existing
objects in the repository according with the changes made to the corresponding
classes. To support such operations, Atlas is able to inform the impact that each
change has in the objects existing in the repository and execute them if the
necessary actions can be performed automatically [
          <xref ref-type="bibr" rid="ref29 ref30 ref31">29, 30, 31</xref>
          ].
        </p>
      </sec>
      <sec id="sec-3-5">
        <title>3.5 Object life-cycles</title>
        <p>Object life-cycle is de ned over a set of object user de ned properties of type,
one for each life-cycle state. Users can de ne several life-cycles for the same class.</p>
        <p>For example, for the application artifact, one may de ne the existence life-cycle
and technical quality life-cycle. For each life-cycle, users can de ne any number
of states, and assign a color to each one, so that objects are shaded with the
color corresponding to the state of the object at the selected date in the EA
view.</p>
        <p>As explained in the next section, Atlas has speci c built-in behavior
associated with the visualization of object life-cycles that requires uses to classify
them as Not Yet Productive, Productive or No Longer Productive. Users de ne
life-cycle states in order and some sates may be declared as Productive. The
states prior to the rst Productive state are considered Not Yet Productive and
states after the last Productive state are considered No longer Productive.</p>
      </sec>
      <sec id="sec-3-6">
        <title>3.6 Visualizing AS-WAS, AS-IS and TO-BE EA views</title>
        <p>In atlas, EA graphical views are generated on-the- y given its unique name, in
the form of an URL as serverURL/RepositoryName/EAViewName?arguments.
This means that, by placing hyperlinks to EA views, users that access and
interact with them outside the Atlas tool in documents or in other web interfaces.</p>
        <p>EA views are de ned in a simple XML language, where one can de ne
containers that can hold others containers or a content query whose result set
determines the objects that will be displayed inside that container. Containers can
be set in a hierarchy and grow and shrink within user de ned limits according
to the number of objects of the query result set. Objects can also be containers,
whenever one wants other results sets to be presented inside.</p>
        <p>Once generated, EA views are interactive interfaces where users can navigate
in time, run prede ned analyses, jump to another EA views and drag objects
between containers, triggering containers out-query and in-query to do the
necessary state update associated with the object movement between containers.
For example, dragging an object of actor John from a container representing
Sales Unit to a container representing Legal Unit will trigger the corresponding
out-query on the Sales Unit and in-query on the Legal Unit containers with the
actor John as argument.</p>
        <p>In what concerns time navigation capability of EA views, in Atlas each and
every EA view is as a movie, where one can see its contents from the minimum
to the maximum date found among all objects that encompass the EA view. As
presented in gure 3, the time bar has two handlers, one on the left for the lower
date and another in the right for the upper date.</p>
        <p>By moving the time bar handlers back and forward one can see the
architecture view in the selected time. The visualization can occur either in Absolute
Mode or Gap Mode. In the Absolute Mode, the view presents the contents that
corresponds to the time selected. Two options can be selected:
{ Default: Only productive objects at selected time are presented. Symbols are
presented in their default color.
{ life-cycle: All objects are presented, but their symbols is shaded with the
lifecycle colors. For example, a typical life-cycle con guration is to shade in grey
the artifacts that are Not Yet Productive at the selected time, and to shade in
red the objects that are No Longer Productive objects at the selected time.</p>
        <p>
          In Gap Mode, the Visualize the view presents the gap between two points
in time Ti and Tf , by shade the objects symbols according to the di erence of
life-cycle state of each object on the selected Times Ti and Tf [
          <xref ref-type="bibr" rid="ref32">32</xref>
          ]. In this mode,
artifacts are marked as:
{ Introduced. An artifact is considered to be introduced between Ti and Tf if
it is Not Yet Productive at Ti but it is Productive at Tf .
{ Withdraw. An artifact is considered to be withdraw between Ti and Tf if it
is productive in Ti and is No Longer Productive in Tf .
{ Changed. An artifact is considered to be changed between Ti and Tf if it is
Productive in both Ti and Tf and if at least one artifact with which it has
a reference to as been introduced or removed between Ti and Tf . The users
can select the depth of the graph traversal analysis and for each step, the
references to be used.
        </p>
        <p>In the next three gures (4 to 6) we present the same EA view with di erent
options and dates of visualization. The rst gure presents the architecture at
10/05/2018 in absolute mode with life-cycle option on. The container in the
middle show the components of application Account Management App, that
consume services in the container on the middle left, that in turn and provided
by applications in the leftmost container. Likewise, the Account Management
App components provide the services presented in the middle right container
that are consumed by the applications in the rightmost container. Bellow, one
presents the data objects used in each service. Objects shaded in grey or red are,
respectively, Not Yet Productive or No Longer Productive at 10/05/2018.</p>
        <p>By switching the life-cycle mode o , the shaded objects (both introduced
and Withdraw) disappear from the EA view, leaving only the objects that were,
are or will be4 productive at 10/05/2018. The corresponding gure is not shown
since it can be easily perceived.</p>
        <p>By moving the left part of the time handle back in time to 05/04/2014, the
visualization switches to Gap mode between 05/04/2014 and 10/05/2018, as
presented in gure 6, where introduced objects appear in green and withdraw
ones appear in red.</p>
        <p>Next, we set the life-cycle mode on again, mixing the Gap and life-cycle
modes, as presented in gure 5, where the evolving objects are shaded in two</p>
        <sec id="sec-3-6-1">
          <title>4 Both the dates used in this example (05/04/2014 and 10/05/2018) could refer to</title>
          <p>the past, present of future.
halves: On the left side, with the color associated with the life-cycle state at the
rst date (05/04/2014) and, on the right side, with the color associated with the
life-cycle state at the second date (10/05/2018).</p>
          <p>The time bar presented in these three gures show four markers, excluding
the extremes, revealing the dates of change in that EA view. These dates
correspond to object life-cycle evolution but can also be traced back to the change
initiatives that have produced such evaluations, as explained next.</p>
        </sec>
      </sec>
      <sec id="sec-3-7">
        <title>3.7 Change Initiatives</title>
        <p>According to cartography principles, enterprise artifacts evolve in its life-cycle
as a result of some planned change initiatives. In Atlas, used de ned class may
be a change initiative class, and more than one change initiative class may exist.
For example, one may de ne the Project class as change initiative of Technology
artifacts, and the Work-Package class for business changing initiatives.</p>
        <p>For simplicity, Atlas assume that change initiatives produce the expected
results at the very end, meaning on the date they become non-productive. To model
a situation where a change initiative produces results before its non productive
date, one must use a hierarchy of change initiatives, where the top one has a
child for each result it has to produce with the non productive date matching
the desired date.</p>
        <p>The relationship between change initiatives and object life-cycle states is a
key factor to simplify the update and management of enterprise artifacts
lifecycle dates. For example, if a project, that is replacing one application by a new
one delays one month, this delay should be re ected in the life-cycle of both
applications, speci cally in the old application retirement date and in the new
application alive date.</p>
        <p>In Atlas this relationship is established by a user de ned reference property
declared at the class level, either at the change initiative class or at the object
class. For example, in a typical scenario, one may de ne the Alive List and the
Retired List reference properties in a project class to identify the objects that
will become alive and retired. Such relationships allow the update of objects
lifecycle according to the life-cycle of the corresponding change initiative. In this
scenario is, the kicko and completion of change initiatives yields the following
behavior:
{ When the change initiative starts: propagate the current date to both change
the initiative alive date and gestation date of objects in the Alive List.
{ When the conclusion date of a change initiative has a new forecast: propagate
the forecast date to the retired date of the change initiative, to the alive date
of objects in the Alive List and to the retired date of objects in the Retired
List.</p>
        <p>
          Such state propagation is not a built-in behaviour in Atlas and must be
congured in state propagation rules associated to object life-cycle. This provides
more exibility and independence regarding to the actual life-cycle states the
user can de ne for each class. A more advanced usage of these dependencies and
rules is to perform repository coherency validation analysis, in particular based
on the time dependent relationships[
          <xref ref-type="bibr" rid="ref33">33</xref>
          ].
        </p>
      </sec>
    </sec>
    <sec id="sec-4">
      <title>4 Conclusion</title>
      <p>The goal we pursuit with Atlas and Enterprise Cartography is to be minimize
the e ort required to provide updated and trustful EA views, in enterprises
where their architecture is the result of many local architectures, each designed
with di erent drivers and optimization factors. So far, we can say that achieving
this goal is fundamentally dependent on the enterprise's ability to provide good
enough plans and descriptions of their change initiatives. Using the scenario
presented in previous section, this boils down to having the Alive List and the
Retired List of change initiatives completed. In such case the e ort required to
keep AS-IS and TO-BE EA views updated is non-existent in practical terms.</p>
      <p>Since the Alive List and the Retired List of a given change initiative represent,
for all practical matters, what needs to be done in that change initiative and
what impact it has in the enterprise, they are also related with the cost, time
and risk of that change initiative. In other words, the can conclude that the more
the enterprise is willing to manage cost, time and risk of their change initiatives,
the more likely will be the success of our proposal.</p>
      <p>However, we also conclude that we still miss a clear and easy mapping
between project management practices and standards with the EA artifacts and
their life-cycle evolution to easy the completeness of change initiatives. For
example, if a project intends to create and deploy a new application service on a
given date on a given infrastructure, then these facts should be stated somehow
in the project plan and deliverables, so that they can be subsequently imported
to complete the Alive List and the Retired List of the corresponding change
initiative.</p>
      <p>
        The Project Management Body of Knowledge[
        <xref ref-type="bibr" rid="ref5">5</xref>
        ] de nes the work-breakdown
structure as a "A hierarchical decomposition of the total scope of work to be
carried out by the project team to accomplish the project objectives and
create the required deliverable." Since enterprise artifacts life-cycle is by de
nition a result (deliverable) of a project, they are likely to appear in project
work-breakdown structure. We are currently working in the establishment of
a more formal mapping between enterprise artifact life-cycle and project
workbreakdown structure[
        <xref ref-type="bibr" rid="ref11">11</xref>
        ]. The idea is to integrate Atlas with the project
management tools used in the enterprise and capture the information needed for
completion of change initiatives and make enterprise cartography a more simple
and accessible capability to enterprises.
      </p>
    </sec>
    <sec id="sec-5">
      <title>Acknowledgements</title>
      <p>This research was supported by the Link Consultings project IT-Atlas (n 11419),
under the IAPMEI, 2020 Portuguese PO CI Operational Program.</p>
    </sec>
  </body>
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