This GSMA document is the first edition of the NB-IoT Deployment Guide for mobile network operators and application service providers. It identifies a minimum set of key NB-IoT features, details key configurations and considerations for deployments in 2017 and 2018. The Guide has been developed by the NB-IoT Forum as an aid in the deployment of NB-IoT networks and devices globally, to ensure smooth interoperability and roaming.
https://www.gsma.com/iot/resources/nbiot-deployment-guide-v3/