SFTP without SSH session access

Hi All,
I'm new to this list, and actually I need an answer for one question. I've already asked this at different places, including comp.security.ssh newsgroup, with no success. So this mail list is my last resort. Please reply if it is possible, or it is not, or whatever.

Suppose someone has telnet and FTP access to his System. Suppose, he wants to restrict telnet from outside his LAN, while still letting FTP working. What does he do? Right, he closes port 23 (telnet) on the router, leaving port 21 (FTP) open.

Now, suppose I have SSH (session) and SFTP access to my system. Suppose, for some a reason, I don't want users to connect from outside the LAN even over SSH to create a command session. And I still want to allow them SFTP access from outside for file transfer. In this case, I can not use the above technique, as SSH and SFTP both use the same port, which is 22. Moreover, SFTP uses SSH for authorization.

The question is, if it is possible to allow users to transfer files over SFTP, while restricting SSH sessions from outside? Thanks,

   Andrey Received on Wed Jun 4 22:48:50 2003