Microsoft provides a couple dozen conference bridges worldwide. Depending on your tenant settings, you may also see several dedicated service numbers assigned to your company for use with conferencing, as shown in the following screenshot:
Audio-conferencing: Microsoft bridge
The table will identify Dedicated and Shared numbers, as well as Toll numbers versus Toll-Free. The assignment of Dedicated and Toll-Free numbers is handled in the voice section.
The only really useful thing you can do from this screen is to specify the default bridge, which is the number that will be displayed in calendar invites and emails when conference ...
