  This work proposes a new and flexible unreliable failure detector whose
output is related to the trust level of a set of processes. By expressing the
relevance of each process of the set by an impact factor value, our approach
allows the tuning of the detector output, making possible a softer or stricter
monitoring. The idea behind our proposal is that, according to an acceptable
margin of failures and the impact factor assigned to processes, in some
scenarios, the failure of some low impact processes may not change the user
confidence in the set of processes, while the crash of a high impact factor
process may seriously affect it. We outline the application scenarios and the
proposed unreliable failure detector, giving a detailed account of the concept
on which it is based.
