Design system where teachers can upload the content and stuedents can view that content. Solve below mentioned problems at a minimum.
1. Teachers should be notified once their content is uploaded
2. Upload should continue even if browser is closed in case it is a browser upload.
3. Will there be any bottleneck on content upload (too much content uplaoding at same time), if yes how that can be solved ?

Number 2 is most difficult for me because if browser is closed then the client connection is closed which implies upload can not continue. Is there any approach to solve this particular problem ?