  We introduce the concept of quantum reliability as an extension of the
concept of network reliability in the context of quantum networks. We show that
this concept is intimately related to the concept of quantum reliability
operator that we also introduce and show a Negami like splitting formula for
it. Considering that the simple factorization formula for classical networks
which is the basis of most of the calculation algorithms does not hold in the
quantum context due to entanglement, a Negami like splitting for the quantum
reliability operator becomes relevant.
