[SpamCop-List] Re: Open Proxy SCBL Rules

[Bert Driehuis]

K. Crocker wrote:

> I made a request of my ISP to reveal the anti-spam steps they take and 
> how effective they are at blocking spam.

The first is a reasonable request. The second is not. Some spammers want 
to fly beneath the radar and stop a spam run to 1,000 recipients because 
they get a bounce that may indicate that they've been found out. Other 
spammers will just not give up until your MX said "250 OK" to them. In 
the first example, blocking one message saves a thousand spams, in the 
second example, blocking a thousand messages will not stop the spam if 
only one slips through. Spam stats are unreliable.

I have seen evidence of both forms and I'm not exagerrating the scale.

 > My ISP was recently acquired by
> another company, so its unclear (at least to me) whether their methods 
> are consistent across both company's servers. Their reply was terse:
> 
>> Currently, we use a number of RBL's:
>>
>> sbl.spamhaus.org
>> bl.spamcop.net
>> dnsbl.njabl.org
>> list.dsbl.org
>> relays.ordb.org
>> dynablock.njabl.org
>> dnsbl.sorbs.net
>> cbl.abuseat.org

That's a pretty comprehensive list. I'd personally throw in the PDL 
because I believe dynablock isn't as comprehensive as it used to be, but 
other than that it is a sane setup for most users. The list is certainly 
more aggressive than I could stomach, if I don my support-role hat.

> I'd appreciate your comments based on this list. Like I said in a 
> previous post, I'm still getting at least 40 spam a day, but I have no 
> idea how many are blocked (I asked and they didn't tell). They have 
> generally been a reliable ISP over the years, but sometimes they lack a 
> certain attention to detail. For example, when I sent my info request to 
> the advertised support address, it bounced with:
> 
> 550 5.1.1 /usr/home/hostmaster/.forward: line 5: ~... User unknown
> 
> Fortunately, their phone works!

Yeah, that really looks amateurish. Then again, I'd pick an ISP that 
makes the odd mistake and is honest over the goliath that lies about 
mistakes and stonewalls its customers any day.

If the outright blocking isn't sufficient, you may want to get them to 
tag all mail with SpamAssassin. That way, you give the worst spammers 
the "250 OK" he craves so much while not having to deal with the spam.

It is impossible to win the war on spam and still leave the US a 
democracy. If you have spare cycles, get your elected representative off 
his proverbial to make sure that law enforcement does their job. Last I 
checked, computer breakins were illegal in the US and the vast majority 
of spam comes from a small number of people in the US breaking US law to 
deliver spam to the tune of around $10bn damages per annum. If I were a 
politician I'd see an opportunity there.