by Christian Herman.
I'm not sure that they're still using the platform, but for several years the Open University used Moodle. They had approximately 200,000 students enrolled concurrently.
Current statistics on Moodle.org show more than 500 registered Moodle sites that have more than 20,000 users. As with any high-volume network system, the more concurrent users the more servers power you'll need, but as long as you have sufficient network hardware, Moodle can handle it.
