Online training on implementing the NRENum.net service for global video dialling.

Summary
This training material will be deployed as a tool for the NRENs that have not implemented the NRENum.net service for their organisations. The guide will show the step-by-step instructions to enable NRENum, how to configure it, how to register with the NRENum.net tree, and the general recommendations to configure terminals, gatekeepers, or SBC.