This section illustrates various different multipoint calling scenarios.

Multipoint conference between endpoints in the same organization

In this calling scenario, the StarLeaf endpoints are in the same organization and have a direct IP route to each other. However, in a StarLeaf multipoint conference, all of the media has to be transcoded, and transcoding is all done by the StarLeaf Cloud Core. Therefore, each endpoint sends and receives all of its signaling and media via the organization’s StarLeaf border controller, through which it accesses the call control and media engines that are needed to make the multipoint conference work.

The figure below shows a multipoint conference between StarLeaf endpoints in a single organization.

Clearly, this situation leads to a higher load on the organization’s Internet connection. In mitigation, because the video contributed from each endpoint in the conference is shown at a much lower resolution than it would be on a point to point call, the bit rate at which each endpoint transmits media is much lower than on a point to point call—typically, 0.5 mb/s instead of 1.5 mb/s.

Multipoint conferences between endpoints in different organizations

When endpoints outside the conference host organization are included in a conference, their signaling and media are routed via the other organization’s StarLeaf border controller (in the case of external StarLeaf endpoints) or via standard H.323 or SIP calls across the Internet to the destination endpoint, as shown in the following diagram.

The figure below shows a conference including external StarLeaf endpoints.

Multipoint conferences including third-party endpoints

In the following diagram the conference includes a third-party endpoint outside the organization that has a public IP address.