Carlos Manuel Rodrigues Machado Autonomic Ubiquitous Computing

The detected action patterns of the users by the system inevitably change over time, so the
system needs to continuously monitor and update its configurations. The constant stream of data
supplied by the actions of the users also allows the system to improve the pattern determination
and associated precision. This process enables the self-optimization of the system.
When any component of the system fails, the user adapts his behaviour. This does not mean
that the user knows how to repair or replace the failing component. The adapted behaviour is a
normal response from the user to a new situation. This new pattern from the user can show a
considerable difference from previous detected patterns. The system detects this new pattern and
updates its reactions. This process can be seen as a self-healing capability from the system. In the
example exposed earlier, it can imagined a failure in a light bulb. The user notices that the light was
not automatically turned ON and the user tries to switch it ON. Because of the failure, the user is
incapable of performing that action and chooses to switch another light in the room. This new
action is captured by the system which adapts to this new situation.
The self-protection on this global view perspective consists in blocking automatic actions
when the detected user patterns appear not suitable to given situations. This can be detected when
a user executes a completely opposite action immediately after an automatic action from the
system. The system backs-off when that interaction has happened, by increasing the threshold for
the activation of a detected pattern. If the increment is sufficiently high, the automatic function can
be completely disabled.
3.2.2 Local View Perspective
In an autonomic system, the local view perspective objective is to preserve the flow of
information and it is not concerned on the functions that use that information. This allows the best
quality data to be always available. This focuses on the way the network and specific devices work
and therefore its capabilities depend on the technology used in a specific implementation.
The self-configuration, in this perspective, aims the autonomic setup of the network
parameters. These parameters include the automatic setting of the network address, the
- 33 -