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MartyBartfast

I've recently been in Email contact with two people who use an Email sender verification system. Basically what happens is I sent them a mail which is held in limbo by the software, which automatically sends me a mail saying "if you're a real person click on this link", clicking the link releases my original mail from limbo and it's delivered to the recipient.

Now I got to wondering what would happen if I was using a similar system, because the verification mail generated by the first recipient would be held in limbo by my system, so I would never know that my mail hadn't been delivered. The verification mail generated by my system would be held in limbo on the recipients system, in a worst case scenario the two systems would just end up ping-ponging mails backwards & forwards until something somewhere gave out under the strain.

Is this a fundemental flaw in the system, or am I missing something?

nelz

Or what if you were sending from a system that had email but not web access. Greylisting is a more system-friendly method of achieving a similar result.
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"Insanity: doing the same thing over and over again and expecting different results." (Albert Einstein)

jjmac

Seems one of the dynamic ip addresses my isp allocates is listed with xbl.spamhaus.org as a spam relay.

It gave me no end of problems a few months back, on some sites. Logging in was ok, but on submitting, the post would be rejected with a message pointing to above site.

I figured some one must have had a spam generator hiding on their box and got scaned while they had that address allocated. Which would then deny access to anyone else that had that allocation if the spamhaus site was configured for filtering.

I guess it's going to remain a big problem for quite a while yet.

jm
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MartyBartfast

Well from what I've seen so far of these verification systems I don't think they're the right solution to SPAM. As Nelz suggests greylisting along with whitelisting & blacklisting seems a more appropriate solution.
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nelz

jjmac that's one of the major flaws of blacklisting. I don't use blacklist services at all, there are plenty of other ways to reject spam without rejecting legitimate mail from unlucky people.
_________________
"Insanity: doing the same thing over and over again and expecting different results." (Albert Einstein)

jjmac

Yes (grin) ... i found it quite revealing. iirc the site stated that they wouldn't remove dynamic addresses without specific contact with the isp. Probably in order to get them to be more aware i would expect. No need to mention, mine really couldn't give a hoot.

The site that drew on the service was getting swamped at the time ... spam scatered all over their forum pages. Just endless lists of url addresses, they must have had every porn site in existence listed, there were so many.

They responded to my complaint very quickly, then removed the block. And said they were only trying that particular avenue as an experiment.

I found it interesting though. As a dynamic address, i would hazard the guess that it must have beeb some sought of 'bot' on someones machine that had that allocation at the time. I would also guess a windows box.

So ... are there 'bots' out there, unnoticed by their hosts ... that would seem to confirm it.

Drove me to total distraction at the time (grin)

jm
_________________
http://counter.li.org
#313537

The FVWM wm -=- www.fvwm.org -=-

Somebody stole my air guitar, It happened just the other day,
But it's ok, 'cause i've got a spare ...