Kautz topologies for all-optical self-routing networks

Kautz directed graphs (digraphs) arise from larger de Bruijn digraphs by the deletion of nodes or from smaller de Bruijn digraphs by additional nodes, respectively. Thus all-optical self-routing networks with Kautz topologies have different properties compared with de Bruijn. Kautz digraphs may be extended by their sum and product graphs and contain planar (crossover-free) embeddings.