Carmen, which version includes video conferencing tool? Moodle doesn't comes with video conferencing included, however there are external plug-ins that would help you achieve that.
Big Blue Button is mainly used, but for that you'll be setting up additional server (Based on Apache
TomCat) as BBB
doesn't runs on standard HTTP servers, for setting up BBB
you'll have to rely on upstream bandwidth, else you can look for third part providers who can provide BBB
that you can integrate in your moodle. If you're setting up own BBB
, then make sure that 1Gb/s bandwidth is dedicated and not shared.
Then there are choices of Zoom or Microsoft Teams - both will not require high bandwidth on your servers - they essentially fetch presenter's video and convert into streams to be presented to 'n' number of audiences.
The dedicated server you mentioned, switch the hard drives to serve 400 concurrent - I meant use SSD's for operations and HDD's for storage.