Abstract
Expander graphs are relevant to theoretical computer science as well as in the construction of high-performance switching networks. In communication networks applications, a high degree of symmetry in the underlying topology is often advantageous, as it may reduce the complexity of designing and analysing switching and routing algorithms. Generalising the method used in [2], we construct infinite families of expanders with large automorphism groups. Other possible extensions of the results in [2] are also discussed.