We consider the multipath communication between a client
and a server that is established at the transport and session layers of an
SDN/NFV protocol stack in a fog computing scenario. We analyze the
reliability function of an associated redundant transport system comprising
two logical channels that are susceptible to failures. The failure
processes of both channels are described by Markov-modulated failure
times that are driven by the transitions of a common Markovian environment.
We model the error-prone system with repair and independent
phase-type distributed repair times by a continuous-time Markov chain.
We identify its generator matrix in terms of Kronecker products of the
underlying parameter matrices that are determined by the interarrival
times driven by Markov-modulated failure processes and the independent
phase-type distributed repair times. We show that the steady-state
distribution of the restoration model can be eectively calculated by
an iterative aggregation-disaggregation method for block matrices and
compute the associated reliability function of the transport system by a
uniformization method.
