Re: Current status?

In article <hPXxk.13$ia.10@xxxxxxxxxxxxxxxxxxxx>, John Santos
<john@xxxxxxx> writes:

Nothing new, just trimming the hundreds of lines of quoted text.

Even if an ISP blocks external port 25 (which their customers would
probably complain about if they are running their own inbound mail
servers, or just on principal :-), do any implement internal firewalls
that block one customer from trying to access another? For Comcast
in particular, if I understand it correctly, each neighborhood is a
LAN on a virtual ethernet running on their cable, so there is not
even a router between you and the guy down the street. The only
place they could put a firewall is on the cable converter box that
converts the cable signal to ethernet in your house (the box commonly
called a "cable modem", though I don't think it is really a modem.)
They could *also* firewall port 25 at their boundaries with other
ISPs and backbone providers, but that in itself would be
insufficient. (They might want to do it anyway to reduce their
internal traffic.)

I'm on Verizon FIOS at home and I know the FIOS converter box
is a router and does NAT and some level of filtering, so inbound
port 25 traffic wouldn't make it to my LAN (or single computer
if that was all I had) unless I actively reconfigure it to pass
port 25 to a designated host (the default is "block"), but I
don't know if the same applies to Comcast cable modems. (FIOS
is point-to-point to the central office, like DSL, so local
"LAN" traffic isn't a separate issue like it would be with
Comcast.) In other words, blocking at the upstream router or
at my home would be equally effective with FIOS or DSL, but
for Comcast, only blocking at the home would catch everything.

As far as making SPAM go away, most of mine seems to come from
China, South America, and other places, and gets sent through
the legitimate ISP inbound mail server. It would have to
be blocked at all those remote ISP's which are completely out
of control. And blocking port 25 inbound through the ISP's
perimeter to anything other than its MX-designated mail servers
would still do nothing about compromised hosts or deliberate
SPAMing by other customers of the same ISP going through its
outbound and then inbound mail servers. It would make the
offending hosts identifiable, but wouldn't stop them. The
ISP would have to notice and then take action (which many of
them do, but they have to send several hundred emails before
anything gets triggered.) The SPAMers don't care. If they
get several hundred sent from each zombie before they get
stopped, they're happy, and the rest of us suffer.

As far as liberals coddling SPAMers, I'm a liberal and I
say "hang'em now. We can have the trial later!"


--
John Santos
Evans Griffiths & Hart, Inc.
781-861-0670 ext 539
.

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