PDF documents can be uploaded by moderators and can be annotated by students and teachers. Saving with or without annotations can be a helpful feature for students joining the learning session in BBB.
(Cyclic Image Update) Videostreams can be submitted to BBB server, but instead of broadcasting the streams to all clients it could be helpful to update a still image in a cyle. Especially when a lot of students join a learning session, it is helpful to see a face from the student, to have a visual impression who is talking. To have a dynamic videostream during the session might not be as relevant as a still image.
Define a default image in the profile of students and teacher will show that still image, even if no webcam is switched on.
The rotating image update could use the bandwidth of a single videostream to update the still image of the participants. Large numbers of participants will increase the time span in which the images are updated but it will not increase the consumption of bandwidth. Especially old computers could benefit from such a video session, with visual impression of participants and low bandwidth consumption especially in rural areas, with poor connectivity to the internet.