In certain network environments it may be required for Videxio service domains to be whitelisted in group policy or for filtering through corporate firewalls.
The following domains are required for the baseline Videxio service (SIP/MyPages/Edge Services).
Skype for Business
More information on Skype for Business as an on premises deployments can be found in this article:
Further MyPages or SIP domains may be required for customers who are using a partners white labeled service. If you are unsure, please contact your Videxio partner for more information.