What are the methods for downloading files at the moment?

Question

Computer networks

Let's say there is a certain set of files, from small to large (several GB). And there are many customers who have our C++ program installed and who need to download these same files. At the moment, it has been implemented as a regular HTTP download from our site. The download speed, of course, leaves much to be desired, especially if the channel is clogged.
So, what other modern options for implementing this task are there to achieve a good download speed, regardless of the number of downloaders (within reasonable limits)?
Cross-platform methods using Boost or other libraries are desirable, but I will not refuse the Windows API either. As a last resort, solutions on QT are interesting, but at the moment it is not used in the project.

Answer 1

torrent or similar p2p systems.
the more downloads of the same content, the more effective they become.
cross-platform for the most do not indulge.

Answer 2

I didn’t quite understand, if you give over http, then it is usually given at the connection speed, if the speed of the disks does not interfere ... How do you give the files themselves? Nginx/Apache or something self-written?

Answer 3

www.libtorrent.org