BigBlueButton is an open source web conferencing and webinar/virtual classroom tool which has been available since 2007. The project has come along way since then, in 2013 it introduced recording, LTI integration, and other long sought after features [release notes: https://code.google.com/p/bigbluebutton/wiki/ReleaseNotes]. In 2015 the platform for synchronous communication also introduced pausing to recording, the ability to do an audio check before starting a session, listen only mode and more (above and beyond the already vast feature list introduced in the previous releases).
Recently, and updated plugin for Moodle 2.6, 2.7 and now 2.8 was released by Blindside Networks, the creator of BigBlueButton. The Moodle activity allows users to leverage all service capabilities directly from a Moodle course where the integration has been made.
Check it out at: https://moodle.org/plugins/view/mod_bigbluebuttonbn
From Moodle, the activity will let you,
- join live sessions
- restrict access
- and much more
You can see the integration in action (based on an earlier release) here: https://www.youtube.com/watch?v=ShB04IoNgk8