Bisecting de Bruijn and Kautz Graphs

De Bruijn and Kautz graphs have been intensively studied as perspective interconnection networks of massively parallel computers. One of the crucial parameters of an interconnection network is its bisection width. It has innuence on both communication properties of the network and the algorithmic design. We prove optimal bounds on the edge and vertex bisection widths of the k-ary n-dimensional de Bruijn digraph. This generalizes known results for k = 2 and improves the upper bound for the vertex bisection width. We extend the method to prove optimal upper and lower bounds on the edge and vertex bisection widths of Kautz graphs.