  Multi-layer complex networks (MLCN) appears in various domains, such as,
transportation, supply chains, etc. Failures in MLCN can lead to major
disruptions in systems. Several research have focussed on different kinds of
failures, such as, cascades, their reasons and ways to avoid them. This paper
considers failures in a specific type of MLCN where the lower layer provides
services to the higher layer without cross layer interaction, typical of a
computer network. A three layer MLCN is constructed with the same set of nodes
where each layer has different characteristics, the bottom most layer is
Erdos-Renyi (ER) random graph with shortest path hop count among the nodes as
gaussian, the middle layer is ER graph with higher number of edges from the
previous, and the top most layer is scale free graph with even higher number of
edges. Both edge and node failures are considered. Failures happen with
decreasing order of centralities of edges and nodes in static batch mode and
when the centralities change dynamically with progressive failures. Emergent
pattern of three key parameters, namely, average shortest path length (ASPL),
total shortest path count (TSPC) and total number of edges (TNE) for all the
three layers after node or edge failures are studied. Extensive simulations
show that all but one parameters show definite degrading patterns. Surprising,
ASPL for the middle layer starts showing a chaotic behavior beyond a certain
point for all types of failures.
