Re: [Asrg] spam down?

Martijn Grooten <> Sat, 26 January 2013 14:42 UTC

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From: Martijn Grooten <>
To: Anti-Spam Research Group - IRTF <>
Thread-Topic: [Asrg] spam down?
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Date: Sat, 26 Jan 2013 14:42:27 +0000
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> First is there actual evidence that spam is on the wane?

I believe there is. Measuring spam is tricky, and different sources may use different definitions and methods, but all agree that the global volume of spam has declined over the past four years.

Note that a reduction from 80% to 67% would mean the volume of spam has halved, rather than reduced by 13%. I believe most sources claim that reduction, since late 2008 (the McColo shutdown), is even bigger than that.

> And if so,
> does it actually have to due in part with authentication? I'd be
> ecstatic to hear that the latter was true, but correlation is not
> causation.

I think it has little to do with that, but that it's mostly because botnets are able to spew out a lot less than they used to. The graph used here shows a strong correlation between drops in the volume of spam and big takedowns:

It's good to keep in mind that the spam "that's not being sent anymore" was relatively easy to block. See for instance:



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