When faults are detected, faulty components are isolated from
non-faulty components so that the faults do not spread. Examples include:
the partitioning of corporate networks from the Internet during the Morris Internet virus,
the normal partitioning of faulty components of the power grid from the rest of the grid, and
the partitioning of the telephone system into critical and non-critical circuits during a national emergency.
Complexity: If designed into a system, fault isolation is feasible. In cases
where fault isolation was not previously considered, a lot of effort may be
required to implement isolation - primarily because nobody knows the list of
links to be cut in order to form the partition, the location of the physical
links that need to be severed, or the effect of partitioning on the two
subsets of the network.