> boxes. I'm beginning to realise that Africa once again equals
> "junk". I wondered whether critical geographers who discover this
> message amongst their spam would let me know so that I can get some
> impression of the extent of this (obviously people who don't check
> this occasionally will be lost
I'll be happy to put my e-mail administrator hat on for a minute – I
spent too many years on the front lines of the spam war. The reality
is that most spam originates from outside the US. Spam these days
typically comes from "botnets" – networks of machines that have been
hijacked by viruses designed for distributing spam. This practice is a
reaction to the fact that would-be spammers in the US and Europe have
a really hard time keeping their connections – the provider cuts them
off quickly when the start spamming. Many, if not all, of the largest
Botnets are run by groups of hackers in Russia.
There are a lot of factors that go into this. First, computers in the
US and Europe tend to be better maintained (i.e. people running anti-
virus software and staying up to date on fixes), which leads to
proportionally fewer compromises by botnets. South Korea used to be a
very problematic country, having the wonderful combination of poor
computer maintenance and excellent connectivity. However, it's gotten
much better in the past few years. Africa, although poorly connected,
is responsible for about 1.6% of spam while the US is about 19.6% –
proportionally, Africa generates way more spam per computer than the
US does.
All of that being said, the vast majority of spam filtering software
is not so crude as to block continents or countries outright. Spam
filtering works (generally) by pattern recognition. The assumption is
(more or less correctly, I would add) that computers sending spam tend
to behave differently from computers that do not and that spam tends
to look different than real e-mail. There are a lot of techniques that
go into it, which I won't bore people with.
Anyway, coming back to the question of maintenance, I think a lot of
computers in Africa (and the rest of the global South) are not as well
maintained, which not only gets them compromised by botnets, but even
legitimate mail can get trapped if the mail server it's going through
isn't kept current on spam fighting practices. In other words, even
the legitimate mail starts to look different from the e-mail
originating in the rich world – and different is bad.
Another thing I've personally noticed when getting e-mail from Africa
(which obviously depends greatly on who's sending it) is that there
tends to be more spelling errors, which again gets flagged as
different. One of the techniques that is used is Bayesian statistical
analysis of your e-mail, in which each incoming e-mail is compared to
the statistical characteristics of e-mail you've gotten in the past to
see if it's consistent. If you get lots of properly spelled e-mail,
then misspelled e-mail looks different...
BTW, very often e-mail providers will including information in the
headers indicating what rules triggered a particular e-mail to get
treated as spam. You have to look at the full headers to see this,
although, sadly, it's often not the most intuitive information.
Anyway, I've probably gone on too long as it is, but I hope this helps.
Darrell
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