Spammers
use a variety of techniques to harvest email addresses. However the two main
techniques are (a) the use of automated spiders and (b) directory harvesting.
Automated
spiders
These
are software agents that are known under a variety of names... spiders,
crawlers, robots and bots. These spiders are the seekers of content on the
internet. They form the basis of how search engines, such as Google and Yahoo!,
work.
Search
engine spiders trawl the internet unceasingly looking for content. Their
searches are based on important words known as key words. The engines keep an
index of the words they find and the website where they find them. Users of the
search engines can then find these sites by keying in the search words. A major
search engine will index hundreds of millions of pages, and respond to tens of
millions of queries every day.
A
spammer collects email addresses in a similar way... by sending an automated
spider throughout the internet looking for addresses that are found on web
pages or in links used to send emails. The spider sends them back to the person
who is compiling the spam list.
The
spammer's spider will trawl a variety of websites looking for addresses. These
include dating sites, chat rooms, message boards, Usenet newsgroups; in fact
any type of webpage that might conceivably contain an address.
If
you have ever sent your address to anyone on the internet, have inserted it in
a form or have you own webpage with your address on it, you can be absolutely
sure that your email address has been harvested by numerous spiders working for
compilers of spam lists.
Directory
harvesting
A
directory harvesting attack, aka a dictionary attack, is another common
technique for creating lists of addresses. It is used to collect addresses from
internet service providers (ISPs), mail services such as Yahoo!, Hotmail and
AOL, and large companies with their own mail servers.
The
attacking software sends millions of emails to addresses on a particular server.
It makes these addresses up using sequences of minor variations on a basic
address. For example, the software could send the same email to a series of
addresses such as akennedy / bkennedy / / ckennedy@yahoo.com and
so on.
Nearly
all these addresses will be invalid, in which case the server will respond with
an SMTP 550 error message. The harvesting software will ignore these addresses.
But every now and then the software will get lucky and the server will respond
with a message that an email address is valid. The software will compile all
the valid addresses into a list for spamming.
The
software will probably send out millions of email messages just to find a few
hundred valid addresses, so this seems a very inefficient way to harvest email
addresses. But the whole process is automated, so it costs the spammer very
little.
Other
email collection techniques
There
are several other ways email addresses can be harvested.
One
of these is to set up a webpage offering to send a product or service free of
charge as long as the user provides an email address. Examples of these kinds
of sites are those that promise to send a joke-of-the-day, daily quotes from
the bible, news or stock alerts, and so on. I recently came across a site that
stated that there could be a registered sex offender in my area and that I
could get further information by email!
In
sum... there is little you can do to avoid having your address harvested by
spammers. The best you can do is to make sure you are running good anti-spam
software and that you keep it up to date.
Paul
Kennedy is the marketing manager of Jupiter
Support (Ireland). He can be contacted by email to paul@jupitersupport.ie.
You can also go to jupitersupport.ie where you can use chat
or Skype to talk with a technician free of charge. Alternatively you can call 0766803006 to
speak to a technician and get free advice. Jupiter Support only charges a fixed
fee of€19.99 to rid your computer of any and all viruses on a no-fix/no-fee basis.
Article
Source: http://EzineArticles.com/?expert=Paul_D_Kennedy
Article Source: http://EzineArticles.com/8137652
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