What spam-filtering methods do you use?

List-based, content-based, word-based, heuristic, or bayesian filters? What about challenge/response systems, collaborative filters, or DNS lookup systems?

Never heard of some of these methods? Check out TechSoup's article Ten Spam-Filtering Methods Explained, where we explain how 10 popular anti-spam methods work and briefly outline some of their pros and cons.

Share your questions and feedback here.

All of the above - :-)

Also, due to the propensity in today's world for spammers to use "image-based" spam to circumvent the above referenced anti-spam approaches, we also use image tone scanning and OCR to identify spam text sent as a pure image.

Don

Spamato may be of interest to those that are looking to have spam filtering at the desktop level. It can be used with various e-mail clients, including Thunderbird and Outlook and uses a few different methods for filtering out the spam (see the site for specifics).

I'm using it at home and it has done a very good job (much better than Thunderbird) at filtering out spam.

Up to the explosion of more sophisticated spam in October 2006, we were very happy w/ SpamAssassin.

Our issue with SA is how it tends to not be highly configurable in an outsourced environment (i.e. I had to find .cf files to load and even then a lot of spam is coming through).

For my home mail server, and a mail server we used to have, DSPAM gets the job mostly done. But of course, my home server has a small universe of users and dissemination of those addresses is quite limited.

So, we have looked at Postini ($$$$), Barracuda ($$$), RoaringPenguin ($$), and ElectricEmbers ($$).

At this point, I like the folks at ElectricEmbers folks for their beliefs and knowledge.

The ideal, IMHO, is to have internal mail servers and an *nix/BSD admin familiar w/ SA and DSPAM. But of course, that's unheard of in NPO's where we all fight a variety of fires...unless you're a foundation w/ $$$ and a dedicated MS Exchange admin.

The opinions above are mine and not those of the Legal Center.

I find Sprint Email Protection Services (SEPS) to be pretty good. It is a 3rd party service that utilizes a variety of methods for filtering inbound and outbound mail. We simply point our mailserver to it's group of servers and it takes care of the rest. Since we have about 300 or so users in our org using email, it costs us $1 per month per user.

Some may find it expensive, but the hassle of dealing with viruses and spam take so much time from the day for a small tech staff, that it is worth it for us.

K. WEST
Union Settlement Assoc
Dir., Information Technology
kwest@unionsett.org

There are alot of free open source software that make great spam, content filtering, blacklist, DNS ip lookup ,network monitoring, VPN, and that software would be IPCop. it is great I have set it up and has worked great with the right add ons and some time to learn how it works. It will will solve alot of your problems from Firewall to smtp filtering and many others issues. I alway suggest this software for budget minded businesses that are looing for an inexpensive way to protect their network.

Postini has proven extremely effective for our organization and our clients. It is flexible, easy to setup and provides great reporting. As a hosted service it minimizes the load on our mailservers by up to 75%. A major benefit is that it allows each user to control their own spam settings. With some server based programs, one user's spam was another users valuable mailing list.