I have tried without -o => 'PreferredAuthentications publickey' this too.
It was not working.
I did telnet. -> telnet 121.241.2.65 22
Its showing this
Telnet: connect to address 121.241.2.65: Connection timed out
although when i used the port provided by the vendor I got this output
Trying 121.241.2.65...
Connected to 121.241.2.65.
Escape character is '^]'.
SSH-2.0-OpenSSH_5.3
Connection closed by foreign host.