RBL Update (Re: Lets go vixie!! rbl)

Bill Becker bbecker at iconn.net
Thu Jun 18 21:04:07 UTC 1998


On Wed, 17 Jun 1998, Dean Anderson wrote:  

> Vix and I have been in agreement that we need a test case.  I volunteered
> to try and find such evidence last year, but I can't. What I've found is
> that ***no major NSP's block spammers***, or least none actually admit to

I can't imagine why they would.  You can't spam a router.

> If you are an NSP, and you are blocking a spammer from transiting your
> network, where you have no relationship with the parties to the email (the

We are not an NSP, and if we were, we would block as little as possible
because blocking costs.  If our downstreams want to block traffic, they
can pay us or they can block it themselves.

And by the way, blocking spam sites at the packet level doesn't make much
sense to me.  In the first place, very little spam (in porportion to the
total) comes from actual spam sites.  If you want to effectively filter
spam, you have to do it at the MTA and MDA levels, and since you need to 
maintain access lists for that, why have a second set of access lists for 
your routers?  And what kind of an informative error message does a Cisco 
send to some poor bastard who's blocked because of his broken mailerserver?

There's also a tradeoff between bandwidth and cpu usage when you are 
filtering packets.  Maybe it would work out to be cheaper if let the 
packets through and then reject the spam at the smtp level.

> If you are really doing what you claim you can, then someone should provide
> some evidence.

I didn't claim what you think i did.  I claimed only that it's feasable
and legal (US) for us to insist that people follow our AUP if they want to
use our network.  People who don't respect us will have trouble sending us
email, getting our nameservers to answer their questions, etc.

Bill




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