As new network technologies appear, the number of different types of networks present around us is even more increasing. Many of them are in a client server relationship. The need for an integrated analysis of their operation is therefore becoming necessary since they are interdependent, not only for achieving a certain level of service to the user but also to have efficient use of resources. The beginning of this analysis is to create a model of the multilayer network. In this paper we outline a methodology we applied to create a model of a multilayer ATM (Asynchronous Transfer Mode) on SDH (Synchronous Digital Hierarchy) network architecture which we used to study a new scheme of integrated fault restoration. Together we describe the most important issues behind creating a model from design and also new issues related to restoration that are born in a multilayer approach.