Universidad Autonoma de Madrid Naudit HPCN Lancaster University Samsung Huawei Technologies This document defines a YANG module for managing flexi-grid optical networks. The model defined in this document specifies a flexi-grid traffic engineering database that is used to describe the topology of a flexi-grid network. It is based on and augments existing YANG models that describe network and traffic engineering topologies. A partner document defines a second YANG module for flexi-grid media channels, i.e., the paths from source to destination through a number of intermediate nodes.