There is an increasing interest for efficient synthesis methods (routing and dimensioning) of large and robust multi-service networks. In the case of ATM networks, the synthesis requires performance guarantees at the cell level (QoS) and at the call level (GoS). Another important feature is reliability, defined as the network robustness in the event of failure. In fact, the planners seek cost-effective networks with guaranteed GoS even in the event of important failures. In this paper we present an optimization model based on cost minimization of multi-rate and ATM networks with SVC connections. The model integrates the notions of QoS, GoS, failures and failure propagation between the physical and the logical level as well as circuit routing.