University of Campinas University of Campinas Evolving networking scenarios (e.g., 5G) demand new multiple administrative domain (aka multi-domain) orchestration models. This document proposes the use of Application-Layer Traffic Optimization (ALTO) services to offer topology and resources addressing network service discovery and provisioning by multi-domain orchestrators. The ALTO services with the proposed protocol extension offer aggregated views on various types of resources contributing to a more simple and scalable solution for resource and service discovery in multi-domain, multi-technology environments.