  Optical networks with multi-core fibers can replace several electronics
networks with a single topology. Each electronic link is replaced by a single
fiber, which can save space, weight, and cost, while having better segregation
and EMI resistance. This is, for instance, of high interest in safety-critical
cyber-physical systems, such as aircraft avionics networks. Finding the optimal
topology requires finding the optimal number of components, component
locations, inter-meshing, and signal routing, while assuring the appropriate
optical power level at each participating device. A Mixed-integer Linear
Programming (MILP) representation is presented for the optimization of the
topology of optical multi-core fiber networks. The optimization approach
retrieves a globally optimal topology with respect to weight or cost, i.e. it
builds the optimal network topology from a set of switch and cable types, which
differ in the number of fibers, attenuation, connectors, and other properties.
The novelty of our approach is the consideration of translucent and opaque
optical switches as well as the representation of cable and device attenuation
directly in the MILP constraints. Moreover, arbitrary installation and routing
resource restrictions are considered. The application of the approach to five
dedicated scenarios yields in each case an optimal solution and validates our
method. The application to an excerpt of an aircraft cabin network shows the
retrieval of the global optimum in less 30 min for a topology with 48 signals
and 23 components.
