We examine a network design problem under the
reload cost model. Given an undirected edge colored graph, reload costs arise at the nodes of the graph and are depending on the colors
of the pair of edges used by a walk through the node.
In this paper we consider the problem of finding a spanning tree of minimum diameter with respect to the underlying reload
costs. We present hardness results and lower bounds for the approximability even on graphs with maximum degree 5. On the other
hand we provide an exact algorithm for graphs of maximum degree 3.
Keywords Transportation problems - Network Design - Diameter - Spanning Tree - Node weighted graphs