Spam. Again.. -- and blocking net blocks?

Mark Segal MSegal at FUTUREWAY.CA
Tue Dec 10 15:40:41 UTC 2002

We did swip the block to the isp (as an assignment, not allocation).. That
is the problem, they kept recursively looking up the assignment.. Maybe they
should block 64/8 or maybe 0/0 :).

Anybody interested in a coordinated denial of service attack? :).


Mark Segal
Director, Data Services
Futureway Communications Inc.
Tel: (905)326-1570

> -----Original Message-----
> From: Michael.Dillon at [mailto:Michael.Dillon at] 
> Sent: December 10, 2002 10:36 AM
> To: MSegal at FUTUREWAY.CA
> Cc: nanog at; owner-nanog at
> Subject: Re: Spam. Again.. -- and blocking net blocks?
> > Problem:
> > For some reason, spews has decided to now block one of our 
> /19.. Ie no
> mail
> > server in the /19 can send mail.
> > Questions:
> > 1) How do we smack some sense into spews?
> Make it easy for them to identify the fact that your downstream ISP 
> customer has allocated that /32 to a separate organisation. 
> This is what 
> referral whois was supposed to do but it never happened because 
> development of the tools fizzled out. 
> If SPEWS could plug guilty IP addresses into an automated 
> tool and come up 
> with an accurate identification of which neighboring IP 
> addresses were 
> tainted and which were not, then they wouldn't use such crude 
> techniques. 
> Imagine a tool which queries the IANA root LDAP server for an 
> IP address. 
> The IANA server refers them to ARIN's LDAP server because 
> this comes from 
> a /8 that was allocated to ARIN. Now ARIN's server identifies 
> that this 
> address is in your /19 so it refers SPEWS to your own LDAP 
> server. Your 
> server identifies your customer ISP as the owner of the 
> block, or if your 
> customer has been keeping the records up to date with a simple LDAP 
> client, your server would identify that the guilty party is 
> indeed only on 
> one IP address. 
> Of course, this won't stop SPEWS from blacklisting you. But 
> it enables 
> SPEWS to quickly identify the organization (your customer 
> ISP) that has a 
> business relationship with the offender so that SPEWS is more 
> likely to 
> focus their attentions on these two parties.
> > 2) Does anyone else see a HUGE problem with listing a /19 because 
> > there
> is
> > one /32 of a spam advertised website?  When did this start 
> happening?
> It's a free country, you can't stop people like the SPEWS group from 
> expressing their opinions. As long as people are satisfied with crude 
> tools for mapping IP address to owner, this kind of thing 
> will continue to 
> happen.
> --Michael Dillon

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