Syncronize files between a mac server and a c# program?
I've data on a mac server, on which I've several files. 
I've to do a c# program which connect to the server and retrieve files which are different.

The server and the workstation will not be on the same network, so I need to have a secure access(the encryption is a plus, but it's mostly about other people cannot go read files on the server).


I taught of several things:

 - Rsync over SSH(but I didn't found any good library on the .net server, which manage ssh and is recent enough)
 - Samba(not secure enough?)/SFtp access(but I need to do myself the hash mecanism, check on dates, ...)

What is my best option? Do you have an other (better) idea?

Thank you very much!
Syncronize files between a mac server and a c# program?
===

I've data on a mac server, on which I've several files. 
I've to do a c# program which connect to the server and retrieve files which are different.

The server and the workstation will not be on the same network, so I need to have a secure access(the encryption is a plus, but it's mostly about other people cannot go read files on the server).


I taught of several things:

 - Rsync over SSH(but I didn't found any good library on the .net server, which manage ssh and is recent enough)
 - Samba(not secure enough?)/SFtp access(but I need to do myself the hash mecanism, check on dates, ...)

What is my best option? Do you have an other (better) idea?

Thank you very much!