Re: Yet another anti spam approach

From: Nigel Wade (nmw_at_ion.le.ac.uk)
Date: 05/11/04 

Date: Tue, 11 May 2004 15:17:47 +0100

Roedy Green wrote:
> I don't know quite how this works inside, but http://www.zaep.com/
> has a fresh approach to spam that should give 100% protection until
> the spam guys decide to attack it specially.
>
> When you send a message to somebody using it, you get an email back
> saying, please visit this URL one time only to get through the spam
> filter. If they visit in 5 days, then the original email and all
> successive ones are passed through.
>
> I wrote them asking how it works. I'm not clear if you have to host a
> website and mailserver for this to work.
>

It looks like a basic challenge/response system.

Very annoying for legitimate senders and generally bypassed by forging the
sender to be the recipient (most people send mail to themselves from
time-to-time and allow it through).

Add to that the number of people who receive false challenges because the
spam has their email forged as the sender and you've got a nice system for
creating even more collatoral spam. 

-- 
Nigel Wade, System Administrator, Space Plasma Physics Group,
             University of Leicester, Leicester, LE1 7RH, UK
E-mail :    nmw@ion.le.ac.uk
Phone :     +44 (0)116 2523548, Fax : +44 (0)116 2523555

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