Presentation can be sent in either of the following modes:
Live mode: All sites can send presentation. The presentation shared is switched along with the video. If the presentation channel is not opened for the video to watch, the presentation shared cannot be switched.
Presentation mode: Only one site (determined by the MCU) has the right to share the presentation. The presentation viewed by each site is switched along with the video. A site can apply for the presentation sharing right. When the MCU gives the floor to a site, the presentation sharing right is granted to the site only when the site clicks the key to send presentation.