Event Verbosity Levels Event Model
SANY D2.3.4 Specification of the Sensor Service Architecture V3 Doc.V3.1
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battery-powered sensors, temporarily unavailable components, such as human observers, and high-reliance systems such as emergency warning systems.
Basically, event creation is a two-step process. First, the action that is signified by the event needs to be observed; and second the observation must be transformed to a
structure that can be processed within IT systems.
SensorSA doesn‟t apply any restrictions on the observation process, i.e. the activity can be observed by a sensor, a human, a piece of software that supervises another
piece of soft- or hardware, event processing systems that generate events based on other events, or any other entity that is enabled to execute observations. The second
step is the transformation of the observation to something that can be dealt with within IT systems, i.e. an event object that reifies the observed happening.
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Update of Events Once generated, events can be updated to allow modifying the event content. The
update of an event may have major effects on events further down the causal chain of related events. Causal chains and updating of events will be further elaborated in
6.4.2.6.
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Deprecation of Events Events shall not be cancelled, i.e. an event exists and continues to be valid until
declared void or deprecated. SensorSA calls this approach the Reliant Event Model. The rationale behind this approach can be found in the ambiguous semantics of the
term cancellation. Cancelling an event could mean that the signified action never happened e.g. false observation by sensing device, that it had happened but is not
valid any longer e.g. a “fire event” after the fire was extinguished, or that it was once true but was modified based on additional observations e.g. reclassification of a storm
once more observation data were received. The validity of events shall be reflected in the event content model. Events are valid
until they become explicitly deprecated.