ASON/GMPLS is promoted as one of the key technologies to reduce operational expenditures (OPEX) of network operators, since it provides the tools for automating the network operations. This paper gives a detailed model and qualitative analysis of the major OPEX-affecting operation processes in the area of core and metropolitan area transport networks. Moreover, a first quantitative evaluation of the changes in the operational efforts induced by ASON/GMPLS is described. The evaluation shows a significant potential to reduce OPEX, which is to some extent independent of the type of operator.