The concept of software-defined networking (SDN) recently gained huge momentum in the industry, driven mainly by IT companies interested in data center applications. In this paper, however, we apply SDN to the carrier domain, which poses additional requirements in terms of network management functions. As a specific use-case we take a virtualized carrier network shared by multiple customers. We consider the current SDN model as defined by the Open Networking Foundation (ONF), including the OpenFlow and OF-config protocols. Through a step-by-step discussion of the rocedures required to configure and manage the virtualized network, we analyze the applicability of the current SDN model as specified by the ONF. As a result, we identify shortcomings and propose necessary extensions to the ONF SDN model. The highlighted extensions include control network bootstrapping considerations, updates to the SDN and NOS model, and most importantly extensions of the OF-config management data model.