Until very recently, only individuals who ran their own mailservers or had access to a "shell"
account to run scripts with were able to use the popular DNS lookup method to filter with SPEWS.
Now there are new methods being provided to people using the Windows® operating system to
filter on an individual basis. We refer to one of these methods as client-side POP email
filtering. This system looks at the incoming email before your email software does. It checks
using various techniques to see if the email is spam. One of the checks used is a DNS lookup
of the IP addresses in the email header against DNSBL based lists.
Three software packages that implement DNSBL lookups while POP email filtering are
SpamPal, according to its website:
How does SpamPal work?
SpamPal sits between your email program and your mailbox, checking your email as you retrieve it. Any email messages
that SpamPal considers to be spam will be "tagged" with a special header; you simply configure your email client to filter
anything with this header into a separate folder and your spam won't be mixed up with the rest of your email anymore!
SpamEater, according to its website:
SpamEater is an advanced spam filtering tool that will rid your mailbox of spam before
you download it with your mail client software! SpamEater Pro uses a complex set of
rules to catch even the most persistent spammers with a 90% or better hit rate! With
the amount of spam being sent ever increasing, SpamEater Pro is a tool that you can't
afford to be without! Don't fret over waiting for your mail to download with all the spam!
Get SpamEater Pro and start stopping it today!
And Email Express!, according to its website:
The program is a liason between your email program and your POP3 and SMTP servers.
The program becomes your email program's mail server. Email Express! can check an email's header
information about its routing servers against an aggregate of RBLs, or Realtime Blackhole Lists.
RBLs are special lists that contain information about various points of abuse in the email system
used by spammers to inject their spam in to the system, and is updated constantly. If a server in
the email headers is found in the RBLs then Email Express! can automatically delete them or
sequestor them in to a special Access table. The RBLs are accessed by Email Express! in real time.
This process is one of the layers of protection that Email Express! offers its users.
SpamPal, SpamEater
and Email Express!
are available for use at no charge, SpamEater is available in a shareware
"Pro" version with extra features and
Email Express! has also added a shareware "Pro" version.
SpamPal also has the ability to include other people's "Plugins"
as part of it's filtering process.
An "alpha" verison of similar software called SpamProxy is
also availible "free for noncommercial use." This software has German language instructions.
Another interesting free POP proxy type system is SAproxy.
This software is based on the popular SpamAssassin spam
identification engine. This software uses blocklists as well as header & text analysis
and collaborative spam signature sytems as part of it's filtering process.
A commercial product, with a free trail, called SARDS is
also available and according to its website:
SARDS acts as an E-mail proxy, sitting between your usual mail program and the
mailboxes you check. SARDS fetches your E-mail, scans it several ways, and then either passes
it on for retrieval by your current E-mail program or drops it into its own trash folder. By
doing things this way, SARDS gives you, the Windows user, the power and tools that mail server
administrators use to protect entire networks.
Internet blacklist checking. SARDS checks mail senders' addresses against public Internet DND
blacklist (DNSBL) servers to see if the sender is a known "spammer," or sender of junk E-mail.
SARDS includes twenty public servers, and you can add more to increase the likelihood of
catching a persistent "spammer."
We still recommend that all people bothered by spam contact their internet service providers
and request they add some sort of filtering to their incoming email systems. Having email
filtered or tagged at the ISP side is far more efficient than at the user side. Several spam
filtering choices are listed and discussed on the SPEWS FAQ page.
|