I was wondering if is it possible to have server that is able to answer to both http and https requests using Poco Library. Probably one option would be to run 2 servers binding different port, is there any other way only using 1 port?
I have implemented https and http servers previously using Poco Library 1.09.
This would most commonly be done by standing up an nginx front end to proxy the request. The advantage of that way is that it's quick to configure and all the standard tools people have for managing https with nginx will work for you -- things like certificate management.
This also isolates your program. It doesn't listen on a public address, just the localhost address, which reduces your security attack surface.
Or if you're going to host at AWS or a similar service, you can let the load balancer handle https, and your program can just worry about http.