Before revision:  The performance and also the lifespan of each topology  in presence of failures in various components are studied against the topology parameters using the proposed approach. Furthermore, these topologies are compared against each other in a consistent settings in order to determine what topology could deliver a higher performance and resiliency subject to the scalability and agility requirements of a target data center design .
After revision:  The performance and also the lifespan of each topology in presence of failures in various components are studied against the topology parameters .