You can connect Moodle with BigBlueButton. This gives you the open source solution you need.
Our open source platform, edloomio, can also be setup with BigBlueButton. Send me a PM if you are interested.
edX (https://edX.org), which started by providing courses from leading universities online, has now made the platform free and open source (https://open.edx.org/about-open-edx) for any organization to host its own courses/ training modules for internal/commercial use.
You will get the required video streaming support and since you won't need to sell the ...