To ensure your Microsoft® Office Live Meeting sessions can accommodate users connecting via their PC or users who only have a telephone (PSTN) connection you will need a Office Live Meeting Audio Conferencing Partner (ACP).
The ACP is a partner organisation that has worked with Microsoft to ensure their audio conferencing service is compatible with Office Live Meeting. You may already be using an audio conferencing service, but does it work with Office Live Meeting (or Office Communications Server R2)?
Once you sign-up with your chosen ACP, you can then enjoy the ease of joining your VoIP users and PSTN users into the Live meeting session.
With a recent update to the list of Audio Conferencing Partners you can now see all the organisations that could offer you a solution in your geographical area. Each partner will offer a core set of features and some will offer more unique features such as support for Break out rooms in Office Live Meeting.
Common features of the PSTN audio integration:
Follow this link that will take you to the updated page showing you the list of features and the list of ACP’s.