On Wed, 31 Aug 2005, Richard Clayton wrote:
> >I thought about recording the first seen HELO from an IP address to a
> >database. If that IP connects and uses a different HELO, it gets
> >blacklisted and thus useless. I have not tried it though.
>
> This will -- in practice -- give you the wrong result with NAT, with
> dynamic address space, and with anyone who runs more than one piece of
> software.
And with any host that supports multiple domains and adjusts its HELO to
suit the current domain.
--
Philip Hazel University of Cambridge Computing Service,
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