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BOOT CAMP 301 (18/11/03) -- SPAM Part 2
The simple anti-Spam
strategies outlined last week tend to be fairly brutal and are best suited to
home users as they run the risk of filtering out legitimate emails, which could
be a problem for business users. Spammers are becoming increasingly
sophisticated so in order to do a really effective job it is necessary to match
their ingenuity and this week we’re looking at a selection of specialised Spam
removal programs and services.
Early attempts at Spam
filtering focused on identifying the spammer through names, email addresses and
ISPs, or by looking for keywords in the subject line or the body of the message.
None of these methods can be relied upon anymore as spammers frequently change
their identity or service providers and have found ways around keyword filtering
by mimicking genuine emails with authentic-sounding subject
lines.
More recent anti-Spam
systems employ a variety of techniques, none of which are one hundred percent
reliable but even the simplest of them should drastically reduce the number of
unwanted messages reaching your inbox.
One of our favourite
Spam-zapping utilities is MailWasher. This operates independently of your email
client program and regularly interrogates your mail server – where your emails
are stored – so messages are not downloaded onto your PC without your say-so.
MailWasher shows what’s there and through a simple learning process and the use
of blacklists, flags up suspicious messages and viruses that can be either
manually (or automatically) deleted, or deleted and ‘bounced’. That’s where the
message is returned to the sender as undeliverable in the hope your address will
be removed from their mailing list. What remains should be legitimate email
messages and these can be downloaded to your PC and read in the normal way.
Bouncing is not as effective as it once was as a lot of Spam is re-routed
through authentic email addresses but the facility to delete Spam before it gets
anywhere near your PC is quite satisfying. MailWasher needs to be used with
care, though, and once deleted messages cannot be recovered. The program is
freeware, with a ‘nag’ screen so it is well worth upgrading to the more advanced
‘Pro’ version, (about £17), there are more details at: http://www.firetrust.com/home/.
SpamNet is an add-on for
Outlook and Outlook Express that uses a web-based database to determine whether
or not an incoming email message is Spam. This system is particularly clever
because the program’s ‘community’ of users constantly updates the database. If a
Spam message slips through a user manually blocks it and the message’s
characteristics or ‘fingerprint’ are added to the list. However, to prevent
genuine messages being maliciously blocked a user has to build up a ‘trust’
rating, which grows as the accuracy of their reports are verified. SpamNet is
currently freeware and is in the latter stages of beta testing, so it will
probably become a paid-for service before long but if you don’t mind being a
Guinea-pig and want to give it a try go to: www.spamnet.com
SpamCop is a
subscription service that intercepts all of the email messages sent to your
email address. It checks for viruses and Spam using a large and frequently
updated database that users help to maintain. SpamCop provides a specially
designed email client so you can pick up your mail, or you can configure your
existing email program to access your inbox. Messages marked as Spam are routed
to a separate mailbox where they are stored for two weeks, after which they will
be automatically deleted. Setting the system up does involve a few
complications, and it works best if your ISP can forward email from your
existing address to a new one but it is relatively inexpensive, costing $30
(around £17.50) per year for the basic single user service. For more information
go to: www.spamcop.com
MailKey is one of the
more advanced anti-Spam systems on the market and it has built up a good
reputation for accuracy. It works on two levels, firstly incoming emails are
checked by the MailKey server against a ‘whitelist’ of trusted contacts or the
presence of a keyword in the subject line, which users issue to friends and
colleagues. If the message fails these tests it is directed to a rejected folder
and MailKey sends an email to the sender, asking them to request a key, so the
message can be authenticated and sent on to its destination. This can only be
done manually by a person at the other end. A spammer’s automated email system
wouldn’t be able to respond so the message stays in the bin, where you can
review it at your leisure, or delete it. Access to your mail is via your normal
email client using a simple add-on, or from a webmail page. MailKey for a single
user is free and it is currently running a special offer – one year free,
normally £59.95 -- on its Platinum service for multiple accounts. You can reach
MailKey at: www.mailkey.com
Next week – Top Ten Traumas
JARGON FILTER
EMAIL CLIENT
Program, e.g. Outlook or
Outlook Express, used to send and receive emails
WEBMAIL
Web site that provides
access to an email mailbox
WHITE LIST
List of approved or
authentic email addresses used to help filter Spam
messages
TOP TIP
Reporting Spam is often
fairly pointless since spammers are extremely difficult to catch and most of
them operate outside of the UK. Some Spam reporting services have actually
turned out to be companies harvesting email addresses, and you should never
reply to or click the ‘unsubscribe’ link on Spam advertising as it will almost
certainly result in even more unwanted email. However, there are plenty of
legitimate organisations dedicated to eradicating Spam and you will find a very
comprehensive list, including links to UK Government departments and agencies
at: http://spamlinks.datapacket.net/report.htm
http://spamlinks.port5.com/report.htm
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