21 Sep
2017
21 Sep
'17
7:20 a.m.
On 09/20/2017 09:04 PM, Robert Brockway wrote:
This is a well established technique known as
Nolisting. I believe the
safest option is for the port to be unbound and thus for a TCP RST to be
sent.
en.wikipedia.org/wiki/Nolisting
I think I've heard of people doing nolisting before and ran across the
term within the last week.
I wonder how effective it is.
I recently wrote a gray mail server (in Perl) that ran into the problem
of the 3rd bullet point in Drawbacks. - My workaround has been to
return ICMP errors, much like nolisting probably does.
I will have to give Nolisting more thought and mess with it.
--
Grant. . . .
unix || die