On Thu, Jun 10, 2010 at 11:31:49PM +0200, Ralf Hildebrandt wrote:
> I heard that there are firewalls/security appliances that supposedly
> can distinguish "somebody using telnet" from "a machine speaking SMTP".
>
> I must admit, it sounds feasible (timing between keystrokes etc.), but
> little useful.
>
> Anyway. Is there such a thing? Does anybody use such a thing?
Why do you want to discriminate against "telnet 25"? Administrators of
sites that want to trouble-shoot connectivity issues with your server
will use "telnet 25" from time to time. There is no need to block
this, it is by far the least likely source of any significant spam
volume...
--
Viktor.
