Lesson videos for a cooking school

Design video upload and playback for an online cooking school. Instructors upload finished lesson videos of 5 to 40 minutes, recorded in 1080p, usually 1 to 4 GB each, about 60 a week. Students watch on phones, laptops and TVs, sometimes on slow connections, and should be able to start quickly and skip around. Only students enrolled in a course may watch its lessons. The school has 50,000 students who watch about 40,000 hours of video a month. Describe the upload path, how videos are prepared for playback, how they are delivered, and how access is restricted.