SSH & iptables

[pch0317 <pch0317@gmail.com>]

Hello
I want to filter traffic on SSH server. I want to ACCEPT only SSH trafic 
on SSH server computer. Packet SSH which receive and send should be 
ACCEPT. Other traffic should be DROP. Which protocol I must use. I know 
that port nr 22 is used default.
So, what I must type to do this?

Thanks
pch0317