There are multiple ways to integrate with VoIP and or SIP. OpenMeetings does not provide out of the box a ready to run VoIP integration / integration to cell phone or usual land lane. The nature of such integrations is that it depends heavily on the infrastructure that you are using and where you would like to integrate OpenMeetings into.

It also depends on a number of factors of which OpenMeetings is impossible to set up for you, for example setting up your VoIP server or provide you with a range of telephone numbers reserved for conference calls in your national phone network. Such an integration project is likely to become a consulting job for a telecommunications consultant.

To get help on the integration you can contact the mailing lists or for example somebody from the list of commercial support .

Instruction how-to set up OpenMeetings SIP-Transport integration for Openmeetings 2.0 .
Instruction how-to set up OpenMeetings SIP-Transport integration for Openmeetings 2.1 .
Instruction how-to set up OpenMeetings SIP-Transport integration for Openmeetings 3.0 .