Ask HN: Self hosting video lessons?

You could just serve the videos via S3/CloudFront and use browser's built-in HTML5 video players with a plain <video> tag.

how would you protect it so that only registered users could access the content?

Look for something called an LMS. There are SaaS providers, open sourced, licensed and selfmade ones.

LMS = Learning Management Platform

Thank you, I had no idea this term existed. A simple search brought up a number of options like Moodle and ATutor.

Have you looked into YouPHPTube? You can host a youtube like web app from a vps.