Nokia Orange Nokia Nokia Huawei Technologies In order to provision an optical connection through optical networks, a combination of path continuity, resource availability, and impairment constraints must be met to determine viable and optimal paths through the network. The determination of appropriate paths is known as Impairment-Aware Routing and Wavelength Assignment (IA-RWA) for a Wavelength Switched Optical Network (WSON), while it is known as Impairment-Aware Routing and Spectrum Assignment (IA-RSA) for a Spectrum Switched Optical Network (SSON). This document provides a YANG data model for the impairment-aware Traffic Engineering topology (TE topology) in optical networks. It augments the technology agnostic YANG Data Model for TE topologies. The topology YANG model provides read-only topology data including optical impairments that can be used for example by a Path Computation Engine (PCE) for calculating an optically feasible path for a new connection before it is established through an optical network.