2026-07-072026-07-07http://salesiana.dossiersoluciones.com/handle/123456789/119323We give a simple and direct treatment of insensitivity in stochastic networks which is quite general and which provides probabilistic insight into the phenomenon. In the case of multi-class networks, the results generalise those of Bonald and Proutiere (2002, 2003).12 pages, to appear in J. Appl. Probab., 44, No 1 (March 2007)Probability60K20text