>> unfortunately our servers are staying in corporate network which desnt have access to outside sftp server and we wanted to use proxy over to transfer the file.
>> Could you please help us with any java sample on sshd connection over proxy for sftp or any documentation to use proxy would be helpful. I don't think this has anything to do with Java or SSH per-se. There are several ways to proxy a TCP connection (not just SSH) - the most common one is proxying over HTTP/HTTPS. It does require some cooperation from the server that is outside the corporate network - simply Google this issue and see if you get any hits that can help.
