SEKE 2012 Proceedings - Knowledge Systems Institute

Figure 6. Steps S1, S2, S3, S4 and S5 of our approach considering the event “CAG2 - Declarant submits declaration”
Both monitorable and operationalizations tasks should be
linked with system services. Operational services have the
objective of return the system to an optimal state in an
autonomic manner. For example, the “Receive CAGED File”
activity is linked to “Service5”
D. Step S4 – Define Contextualization
Both contextualization and NFR are i mportant factors
to be cons idered as they can guide the execution of
operational tasks that must provide autonomic adaptations
in the system in order to return the equilibrium in face of
incoming perturbations [16]. Hence in this step we define:
(i) Variation Point; (ii) V ariants; (iii) Context; and (iv)
NFR attributes values. The 3 contexts (C1, C2 and C3)
present in Figure 6 (box S4 are defined in TABLE
II.
In this activity we state metrics to be monitored, i.e. we
delimit the environment context that influences the choice of
the system adaptation. In this sense, given that in our running
CAGED there is a deadline for declaration submission, it is
important to measure the daily reception. As observed in
Figure 7, the reception rate peaks during the first seven days
of the month. This trend has to be considered in case of a
correct adaptation.
TABLE II.
Task
Receive
CAGED
File
CONTEXTUALIZATION OF AUTONOMIC BUSINESS PROCESS
Variation
Point
Response
Time
Deviation
Contextualization
Variants Context NFR
Increase
Reception
Rate
Decrease
Reception
Rate
Deviation
Reception
Rate
C1: ReceptionTrendIsOK=
true and
LastThreeCycleIncreasing=
true
C2:ReceptionTrendIsOK=
true and
LastThreeCycleDecreasing=
true
C3:ReceptionTrendIsOK=
false and
LastThreeCycleIncreasing=
true
Response
Time >=
220ms
Response
Time =
220ms
E. Step S5 – Define Service QoS
All defined and linked services, represented as ServiceID
in Figure 6, box S5, must be instrumented according to SLO.
The definition of QoS is based on NFR attributes and
represents the characteristics that must be guaranteed by each
monitorable business activity. Considering the four send
activities and one reception activity of our running example,
the system must provide a Response Time less than 220ms to
each one.
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