As of today, solution for this is using SSL (ex HTTPS, SSH etc). these solutions are for the enduser.
They work great job at client - they warn if the connect to other servers, or if there is a man in middle etc, but do very poor job at server.
Now when we come to other end, backend hasn't have any thing as such. They are not sure weather backend is direclty communicating with enduser or with a proxy server. There is no way to backend to figure this out.
I am looking for a tool which I can integrate this to my frontend and backend for detecting if proxies are being used in between (man in the middle).