Orienting Cayley graphs generated by transposition trees

Day and Tripathi [K. Day, A. Tripathi, Unidirectional star graphs, Inform. Process. Lett. 45 (1993) 123–129] proposed an assignment of directions on the star graphs and derived attractive properties for the resulting directed graphs. Cheng and Lipman [E. Cheng, M.J. Lipman, On the Day–Tripathi orientation of the star graphs: Connectivity, Inform. Process. Lett. 73 (2000) 5–10; E. Cheng, M.J. Lipman, Connectivity properties of unidirectional star graphs, Congr. Numer. 150 (2001) 33–42] studied the connectivity properties of these unidirectional star graphs. The class of star graphs is a special case of Cayley graphs generated by transposition trees. In this paper, we give directions on these graphs and study the connectivity properties of the resulting unidirectional graphs.