In this paper, we split the service management layer, as defined in the Telecommunication Management Network (TMN), into two sublayers, namely the service application management sublayer and the service network management sublayer. The former deals with managing the mapping of the non functional requirements into functional constraints over the telecommunication service of interest, while the second reveals the management details related to meeting the functional requirements over that service. At each sublayer, we propose an information model and emphasize the correspondence with the other sublayer