DYNAMIC BUSINESS TRANSACTIONS CONTROL
An Ontological Example: Organizational Access Control with DEMO
S´ergio Guerreiro
1
, Andr´e Vasconcelos
2,3
and Jos´e Tribolet
2,3
1
Universidade Lus´ofona de Humanidades e Tecnologias, Escola de Comunicac¸˜ao, Artes
Arquitectura e Tecnologias da Informac¸˜ao, Campo Grande 376, 1749-024 Lisbon, Portugal
2
CODE, Center for Organizational Design & Engineering, INOV, Rua Alves Redol 9, Lisbon, Portugal
3
Department of Information Systems and Computer Science, Instituto Superior T´ecnico, UTL, Lisbon, Portugal
Keywords:
Control, DEMO, Observation, Ontology, RBAC, White-box.
Abstract:
This paper discusses the need to design control in the dynamic business transactions (DBT) of an enterprise.
The concepts offered by the classical dynamic control systems (DSC) field are useful for identifying the main
constructs. However, the complexity that today exists in the DBT is too high to be solely controlled by the
analytical DSC approaches. A white-box ontology-based approach, supported by DEMO, is used to identify
the core concepts required to enforce control in a DBT. Organizational access control exemplifies our proposal.
1 INTRODUCTION
This paper addresses the problem of enforcing control
in the activity of the organizations. In general terms,
it is related with the ability to drive, with a bounded
effort, the operation of the enterprise towards a stable
state whenever occur changes or perturbations. We
are focusing in this issue but with a specialized view,
which is how to enforce control in the transactions
that operates in a real run-time organizational envi-
ronment, in order to face the misalignments between
the operational conditions and the references defined
by the organizational models. The way that this spe-
cific research problem is being located is innovative
because it considers that nevertheless the quality of
the models definition that the organizations have, they
are not enough to guarantee the actors follow them in
the reality. Hence, a continuous observationof the op-
eration is needed to identify the misalignments with
the models and then to take corrective actions when
needed.
From the foundations of the software engineer-
ing point of view, the adaptability quality of the soft-
ware when facing change is broadly referenced, e.g.,
the recommended practices for software requirements
IEEE 830-1998 (IEEE830, 1998) identifies ”adapt-
ability as non-functional properties of a system that
should be included directly in its design. Roger
Pressman, in (Pressman, 1992), a consensual clas-
sical reference in software engineering, states that
”the adaptability quality is classical identified as the
aim in minimizing the software deterioration due to
change”. More contemporary in the normalized sys-
tems theory presented by Mannaert et al., in (Herwig
and Verelst, 2009) (Mannaert et al., 2008), a strong
focus is given to the adaptability of a system: ”a de-
sign pattern needs to be stable with respect to an-
ticipated changes”. From the organizations point of
view, Jan Dietz in (Dietz, 2006) refers that Enter-
prise Engineering (EE) is composed of the follow-
ing missions: Enterprise Ontology (EO), Enterprise
Architecture (EA) and Enterprise Governance (EG).
From our perspective, we argue that software sys-
tems perform a key role in the operation of the or-
ganizations, however, if we want to control the ful-
fillment of the organizational goals by its persons and
machines within the stated complexity, then the tech-
nological independent approaches from the enterprise
engineering field (based in white-box solutions), such
as DEMO ontology (Dietz, 2006), should be used to
define comprehensiveness, coherent, conciseness and
consistent (C4-ness) designs of the organization. Ba-
sically, it is a matter of abstraction, we cannot han-
dle all the complexity directly at the software engi-
neering level. Control in organizations is not only
concerned with the electronic artifacts but rather with
the communication between persons and between per-
sons and machines, within public or private compa-
nies. It is interesting to notice that this concern is not
recent, early in 1965, Emery and Trist (Emery and
549
Guerreiro S., Vasconcelos A. and Tribolet J..
DYNAMIC BUSINESS TRANSACTIONS CONTROL - An Ontological Example: Organizational Access Control with DEMO.
DOI: 10.5220/0003702905490554
In Proceedings of the International Conference on Knowledge Engineering and Ontology Development (SSEO-2011), pages 549-554
ISBN: 978-989-8425-80-5
Copyright
c
2011 SCITEPRESS (Science and Technology Publications, Lda.)
Trist, 1965) refer that a company is a open system
where its behavior is only explained when analysed in
conjunction with its interactions with the surrounding
environment. Later in 1978, Geert Hofstede’s work,
in (Hofstede, 1978), proposes that control should be
formed and evaluated as a homeostatic model rather
than a cybernetic model. Homeostatic control model
considers that there are a large number of interrelated
cybernetic systems within an organization, executing
different business services and working side-by-side
which usually involves communication between Hu-
mans and machines. Much more recently, Jos´e Tribo-
let and Rodrigo Magalh˜aes, in the reference (Tribolet
and Magalh˜aes, 2007) also state that agility and real-
time reconfiguration capability (Santos, 2007) are re-
quirements to the maintenance of the organizations.
Yet, the understanding and definition of the degrees of
freedom between the DBT, the functional capabilities
and the hierarchical power must be deeper researched.
Also recently, Jan Hoogervorst (Hoogervorst, 2009),
in the EG field, states that the increasingly complexity
is characterised by an increase that follows the size of
organizations. Thus, precise models that are able to
deal with this complexity without exploding in terms
of size are needed. By other words, the models should
be able to follow, at the same pace, the increase in the
size of companies.
The research related with the enforcement of the
control in organizations require an investigation pro-
cess that is incremental throughout time and that is
obtained by a bottom-up, and step by step, knowl-
edge acquisition. Our aim in this research is to ac-
quire knowledge regarding the integration of the ac-
tual enterprise ontology state of the art with the ac-
cess control modes to obtain a contemporary EG so-
lution. In line, this paper presents the result of a set
of steps to design an EG solution in the ontological
field. The steps are integrated in a research process
where the former iterations affected the remain ones.
It allow the interaction of the work with the commu-
nity while developing the solution, thus making align-
ment with the academic and entrepreneurial reality,
and also allowed the researchers to learn from the er-
rors while developing the theoretical and experimen-
tal artifacts. We clarify that this research does not fol-
low a pure design-science research (DSR). Piirainen
et al., in the reference (Piirainen et al., 2010), stud-
ies the DSR developments stating that the following
steps are required: identify an IT organizational prob-
lem, the aim is to identify and solve real problems
that exist in the daily life of the organizations; demon-
strate that no solution exists; develop IT artifact that
addresses this problem; rigorously evaluate the arti-
fact; articulate the contribution to the IT knowledge
base and community; explain the implications of IT
management and also to the reality of the enterprise.
Actually, this paper uses the identification of organi-
zational problem, the development of ontological ar-
tifacts to address the problem and then the rigorously
evaluation, using argumentation, of the artifacts com-
bined with some other steps.
The remaining of the paper is organized as follow.
Section 2 identifies the typical perspective where the
dynamic systems control is used. Then, section 3 pro-
poses a feedback loop applied to the DBT. Section 4
exemplifies the DBT control using an access control
approach. Finally, section 5 concludes the paper.
This work was partially supported by a PhD schol-
arship, SFRH/BD/43252/2008, FCT, MCTES, and
also supported by PTDC/CCI-COM/115897/2009,
MOBSERV.
2 DYNAMIC SYSTEMS
CONTROL
The aim of controlling dynamic systems is to gain ef-
ficiency in their operation, thus achieving the same
results but with less resources usage. From a histor-
ical point of view, the first significant work in auto-
matic control was James Watt’s centrifugal governor
for the speed control of a steam engine in the eigh-
teenth century (Ogata, 1997). Since then, major ad-
vances have been made in the research of the systems
control theory, many of them were driven by the ad-
vent of the digital computers. It worth noticing that
control systems are mainly developed by the automa-
tion field, raised by the need to implement automatic
supervision since the industrial revolution. A con-
trol approach is composed of two main parts: (i) the
controller and (ii) the controlled process. The con-
troller is responsible to control the process, where a
feedback control system is the system that maintains
a prescribed relationship between the output and the
reference input by comparing them and using the dif-
ference
1
as a means of control (Ogata, 1997; Franklin
et al., 1991). This difference occurs because of two
reasons: (i) the interaction of the controlled process
with the exogenous
2
factors (for instance, a distur-
bance) and (ii) the endogenous factors (for instance,
a breakdown). Along with this consideration, it is re-
marked that to control a process using the dynamic
systems control concepts it is demanded the full dy-
namic specification of the process, mainly using ana-
lytical approaches. Once the dynamic of the process
1
Sometimes also referred as innovation.
2
Originating from outside and endogenous from within.
KEOD 2011 - International Conference on Knowledge Engineering and Ontology Development
550
is presented then the controller is designed and fine-
tuned to deliver a finite and bounded process output
with a set of finite and bounded control initiatives.
Returning to the organizations field, the analyti-
cal models to express its functioning are not available,
due to its complexity and with the intertwined human
activity that exists in reality. Our knowledge about
these phenomena’s is only partial. Therefore we are
not able to follow a similar research path as the one
followed by the classical DSC. Yet, the DSC concepts
are engineering-based founded and forms a relevant
starting point to identify what is desirable to achieve
in the scope of organizations. From the other hand,
control exists in all areas of expertise, and conversely,
it is not exclusive to DSC. Nonetheless, the advances
of control concepts in the enterprise engineering field
of expertise are still not defined in a consensual way,
neither are proposed with an essential ontological per-
spective. Thus, the DSC approaches presented in this
paper aims at identifying the concepts that are use-
ful for the development of the control concepts in the
enterprise engineering scope.
3 DYNAMIC BUSINESS
TRANSACTIONS FEEDBACK
CONTROL
Actually, considering DEMO (Dietz, 2006), it already
controls the DBT in organizations, because it guaran-
tees that the transactions are formed accordingly with
an essential ontology that is compatible with the com-
munication and production, acts and facts, that occurs
in the reality between actors of the different layers of
the organization (D-, I- or B-)
3
. Hence, when a DBT
is fully DEMO compatible then we havethe assurance
that the designed communication and production, acts
and facts, will replicate the set of possible combi-
nations that the actors do in reality. Steven Kervel,
in his references (Kervel, 2011; Kervel, 2009), in
fact, proposes to control the operation of the transac-
tions using a state machine, based in the Ψ-theory
4
of
DEMO, that keeps track of the allowed states where
a DBT is. In other words, when a DBT is correctly
3
The organization of every enterprise can be conceived
as a layered nesting of three parts, called aspect orga-
nizations: the B-organization, the business actions take
place. It consists of B-actors and B-transactions; the I-
organization, supporting infological actions take place. It
consists of I-actors and I-transactions; the D-organization,
supporting datalogical actions take place. It consists of D-
actors and D-transactions.
4
Ψ-theory that stands for PSI: Performance in Social In-
teraction (Dietz, 2006)
designed regarding the desire of the organization and
when the actors executes their actions in respect with
the designed DBT then the problem is supposed to be
solved. However, in this paper we state that this is not
the case in most of the situations. Most of the times
the actors do not follow the designed DBT, in fact,
they execute parts of the business that is again proba-
bly compatible with DEMO but it is not what has been
previously defined by the organization. Having this
kind of situations in mind, then we propose a solution
that observe the operation and that actuates over the
DBT models.
In more detail, the function of controlling a dy-
namic system requires the following aspects:
1. the ex-post
5
observation;
2. the actuation;
3. the ex-ante knowledge regarding the dynamics of
the system to be controlled;
4. the ex-ante references specification;
5. the controller which might be composed of differ-
ent layers of competence.
Our proposal combines these concepts with the ac-
tual knowledge offered by the Enterprise Engineering
field in order to develop control functions applied to
the companies. The dynamic of the organizations is
captured by the transactional design and operation.
A transaction is defined by the transaction axiom of
Ψ-theory. Furthermore, we settled that a separation
between the transactional models definition and the
transactional instances must be considered in order to
differentiate the reference from the operation and thus
identifying the innovation. The transaction axiom is
considered to be the organizational throughput, with-
out it the organization does not exist. The importance
that is attributed to the transactional concern justifies
the first option to bound the solution to the observ-
ability to the operation of the transactions.
In line with the previous considerations, we re-
mark that this solution nevertheless being located in
the ontological field it is detailed enough to be a solid
starting point to allow its implementation by the soft-
ware engineering field. For the reason of having a
normalized approach the solution is designed with the
DEMO ontology and is also to be used in the DEMO
models. In practice, it does not redefine the DEMO
ontology, but rather defines a set of control patterns
that should be included in the DEMO models when-
ever EG is alleged.
Figure 1 presents two control diagrams that have
5
The term ex-post is defined by the expression: ”after
the event”, conversely, ex-ante is defined by the expression:
”before happening”.
DYNAMIC BUSINESS TRANSACTIONS CONTROL - An Ontological Example: Organizational Access Control with
DEMO
551
Enterprise
Governance
Session(s)
Enterprise dynamic system
DEMO
model
DEMO
model
DEMO
models
D
E
M
O
m
o
e
l
s
DEMO
models
DEMO
model
DEMO
model
DEMO
models
D
E
M
O
m
o
e
l
s
ACM
models
DEMO
model
DEMO
model
DEMO
models
D
E
M
O
m
o
e
l
s
Business
Rules
Environmental
changes
PNS
(peripherical
nervous system)
CNS
(central nervous
system)
Ex-ante
Ex-post
run-time
ID control
A13
Access
provisioner
A12
Model
provisioner
A11
Business
rules
provisioner
A04
Interceptor
A02
Model
manager
A03
Access
controller
CA04
User
T04
Observation
of run-time
session
Business rule
management
T12
Model
management
Access
management
Enterprise Governance
T01
Business rule
definition
Model
definition
T03
Access
definition
T05
run-time
control
A05
Run-time
controller
A06
Run-time
access
controller
A07
Business rules
engine
A08
UUID
checker
T07
T08
T06
run-time
access control
run-time
business
rule control
CPB14
CPB15
CPB16
CPB17
CPB18
CPB19
CPB15
CPB17
A
0
A
0
A
T13
A01
Business
rule
manager
T11
T02
CPB16
Figure 1: Comparison between the initial proposed control and the obtained ontological control. In the top: using free design
figures. In the bottom: the ISM ontological control design that is obtained in the end of DEMO methodology execution.
the previous 5 concerns in mind. In the top of the
Figure an information flow is designed using a non
formal specification. The aim is to share the idea of
a feedback loop in the scope of the organization op-
eration. Only informal blocks and arrows are used to
express correspondingly the control components and
the information flow that exists. The solution controls
the activity of the actors, checking misalignment be-
tween the ex-ante models and ex-post observations.
A session execution includes all the ex-post observa-
tions in a real organizational environment and is used
to trigger the EG kernel. EG check the misalignments
and the result is one of the following counterparts: (i)
a permission or denial of access to the activities that
are being executed in the current session and / or (ii) a
change to the ex-ante models. The first counterpart is
based on the ability to control using a systemic view
of the transactions of what is being done and if that
complies with the ex-ante DEMO and access control
models. The result obtained is only a grant or a revoke
to execute the actor’s activities. The second counter-
part is based in the ability to control using a systemic
view of the historical transactions of what is being
done and if that complies with the ex-ante business
rules. The result is one of the following actions: a
change in the business rules, a change in the DEMO
model or a change in the access control model.
In the bottom of the Figure 1, an Organization
Construction Diagram (OCD) from DEMO is de-
picted to specify the actors, the production and co-
ordination banks, the boundary and the information
flow. The same concepts presented in the top of the
figure are also herein expressed. But more detail re-
garding the involved transactions of the ontology are
identified. Some few considerations are made regard-
ing this model. An information link exists between
A12 and T13 to obtain the access configuration from
the DEMO model definition during the configuration
phase of the references. The A07 has three informa-
tion links to the T11, T12 and T13. They correspond
to the control action that are taken when any mis-
alignment occur. T11 corresponds to a self-change
in a business rule, T12 corresponds to a change in
the DEMO model to be controlled, it is expected to
be performed by the model manager which is a per-
son and T13 that corresponds to a change in the ac-
cess management. CPB16 refers to the Period that the
EG is being considered, by other words a time frame
where the control makes sense, hence a information
link exists with its boundary, meaning that all the ac-
tors and transactions are supported in this composite
production bank.
KEOD 2011 - International Conference on Knowledge Engineering and Ontology Development
552
4 ORGANIZATIONAL ACCESS
CONTROL EXAMPLE
This section exemplifies the proposed ontological de-
sign in the scope of an organizational access con-
trol system. Nevertheless the development of the
role-based access control (RBAC) concepts, from the
access control modes (ACM) community, this ap-
proach is only helpful for specifying and implement-
ing the structural security access concerns for a sin-
gle organizational silo (Sandhu et al., 2000). Typi-
cally, the ACM follows predefined policies that are
applied to a specific application layer of an organi-
zation. Examples of such approach are the discre-
tionary access control (DAC), mandatory access con-
trol (MAC), role-based access control (RBAC), time-
role-based access control (TRBAC), Orcon or Chi-
nese wall (Ferraiolo et al., 2001; Ferraiolo et al.,
2007). In this scope, we are proposing, in Figure 2,
the WOSL (Dietz, 2005) design of RBAC access in-
tegrated with the DEMO ontology.
R03
R06
R13
Access
Period
User
Role
U is mapped in R
and constrained by C
Constraint
R is mapped in P
and constrained by C
Permission
Static
Constraint
Dynamic
Constraint
URC
P RC
R is enforced in AR
P is enforced in FT
P is enforced in AR
AR R
P FT
P AR
DEMO: Elementary
Actor Role
DEMO: Fact type
DEMO:
Action
Rule
A
A
A
P
P
P
The run-time permission
of access is Permission
A
P
The run-time role
of access is Role
A
R
The run-time RPC
of access is RPC
A
RPC
The run-time constraint
of access is Constraint
A
C
The run-time URC
of access is URC
A
URC
Access A has been
controlled for period P
Access A has been
defined for period P
Figure 2: WOSL for governance enforcement in DEMO on-
tology: the RBAC state space representation.
The User is an external category that is related by
a ternary fact type with its Role and its Constraint.
A Role is related by a ternary fact type with its Per-
mission and also with its Constraint. A Constraint is
specialized by the categories Dynamic Constraint and
Static Constraint representing design restrictions that
allow configurable access authorization, e.g., separa-
tion of duties. The first one is calculated online and is
related with the Session enforcement by a binary fact
type and the second is calculated offline related with
the Model also by a binary fact type. The Access cat-
egory keeps the state of the access configuration and
corresponds exactly to the ve reference laws decla-
ration with: (i) the Permission; (ii) the Role; (iii) the
Constraint; (iv) the fact type regarding the constrained
mapping between the Role and the Permission and (v)
the fact type regarding the constrained mapping be-
tween the User and the Role.
From the other hand, in the right part of Figure 2, the
integration between the Access and the DEMO con-
cepts is formally defined by:
(i) a binary fact type relating the Role and the
DEMO:Elementary Actor Role, this relation is
not established with the DEMO composite actor
roles because they are outside the scope of the or-
ganization;
(ii) a binary fact type relating the Permission and
DEMO: Fact type, where a fact type is considered
as an entity that is able to be created, removed or
updated in some way during the DBT execution;
(iii) a binary fact type relating the Permission and
DEMO: Action rule, where an action rule is con-
sidered as an entity that executes an atomic part of
the DBT;
(iv) a mutual exclusive law between Permission
with DEMO:Fact type and DEMO:Action rule,
theoretical in this way we are controlling the per-
mission to the DEMO action rule that are spec-
ified in the action rules specification (ARS) and
to the DEMO Fact type in the state model (SM).
However in practice if the transactions are prop-
erly decomposed to only handle a fact type inside
each action rule then it is enough to integrate the
Permission with the DEMO action rule.
Conversely to classical approaches in the scope of se-
curity, the explained integration between Access and
DEMO allows not only to enforce the access control
in the invocation of the DBT but, by the contrary, it al-
lows a run-time control of all the action rules and fact
types that are used within all the scope of the DEMO
DBT instantiation. This approach has the advantage
of fine-control the access of each user to the artifacts
and also in the capability of changing the configura-
tion in run-time with a direct consequence in the ex-
ecution of the DBT. For instance, when some kind of
action is taken in reaction to a session condition is
order to conform with the business rule, model defi-
nition or access definition that are provisioned.
As one could notice a intertwined between the
RBAC implementation and the constructs of DEMO
models exists in this proposal. One clear advantage
of using this proposal is to obtain the RBAC role and
permission automatically from the previous designed
DEMO models. Which means that only the assign-
ment of each user to a role must be done by the orga-
nization.
DYNAMIC BUSINESS TRANSACTIONS CONTROL - An Ontological Example: Organizational Access Control with
DEMO
553
5 CONCLUSIONS
Actually, the capability to fine-grained control the ac-
cess to the artifacts of an organization, or even, the
capability to define and implement business rules, are
most of the times, decoupled from the enterprise de-
sign. The practical consequence of this decoupling, is
(i) the duplication of effort in the control and models
design counterparts and (ii) with the designed mod-
els not aligned with control. Nowadays, a change in
the control requires a change in the model design, and
vice versa. Integrating the access control at the mod-
els design enables a fine-grained access control to the
artifacts directly in the design with a perfect align-
ment that enables the continuous changes throughout
time. Moreover, this integration enables a full ob-
servability of the operation of the enterprise and thus
allows the enforcing of business rules that are able
to react in run-time based in the actual and historical
observations. As a consequence of this, the business
rules are kept as directions that are truly followed by
the organization.
This paper defeat a completely different approach
when compared with non ontological models or even
with models that are solely black-box oriented. We
accept that in order to understand control it is cor-
rect to view the models and the control principles us-
ing a black-box approach, yet the white-box concepts
that relate the separation from the controller and the
controlled process should be researched and precisely
ontological specified if a real implementation is ex-
pected. It is not enough to consider only the black-box
approach. On the other hand, a white-box approach
enables (i) the continuous observation of the design
restrictions of the run-time DBT from the inside and
then (ii) to actuate with a change in the DBT models
when needed. In the limit, parts of the control could
be performed by automatic systems rather than exclu-
sively performed by actors.
For short, our approach represents an effort for con-
ceptualizing the control patterns that should be in-
cluded in the design of the real systems that supports
the organization. Moreover, the control concepts pre-
sented herein are directly related with the EG area re-
garding the lower level of governance for a DBT. For
other aspects of the organization, other control lay-
ers should be further considered. Despite the con-
cepts that are presented in this paper, further research
is needed to design a full ontology for the control of
the DBT. In particular the concepts of business rules
enforcement. It is also needed to develop automatic
tools to design and validate the ontological models.
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