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Spam filter service

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There is likely a market for a good spam filter service that is easy to use and effective. Most of the ones that we’ve seen require complicated setups, rely on locally installed software, or have limited features.

The ideal service would allow a user to check email through POP3 or IMAP, function as a filtering proxy, and allow users to configure their accounts over the Web.

Email protocols.

Offering both POP and IMAP services is a must. While the majority of email users use POP to check their mail (most don’t even realize they have an option), many users that read mail from multiple locations have turned to IMAP for mail management. Most services only offer POP, making them useless to power users.

Providing an IMAP proxy is more difficult than creating a POP proxy, and since most users don’t use IMAP, it is understandable that existing services don’t offer IMAP. However, IMAP users tend to be power email users and are more likely to purchase advanced email services.

Proxy Server.

The service should provide a proxy server that filters mail as it is checked. Many of the services available work by downloading email from your mail server to theirs. When a user checks mail, their email program checks the filtering service’s server.

We think this approach is inadequate. This approach requires that a user’s mail be stored on the servers of the filtering service, rather than their office or ISP servers. Many offices and ISPs have Web-based or other alternative remote mail access capabilities that would be lost if the mail is no longer on those servers. AOL members, for instance, would no longer be able to access their mail through the AOL interface. Another obvious disadvantage is that corporations may not want potentially sensitive email stored on servers outside their control.

A filtering proxy functions by acting as a middleman between the user and their mail server. The user changes their mail software’s settings to request mail from the proxy server, which passes each mail command through to the primary mail server. As the messages are retrieved, the proxy filters them based on criteria defined by the user. The proxy doesn’t store the messages; it only acts as a filter between the user and their mail server.

Email Filtering.

The user can tell the service how they would like the proxy server to filter the mail and what to do with it once it is filtered. The proxy server will use a rules-based engine similar to that used by SpamAssassin. The user can easily configure the filtering engine by choosing which rules to apply. Depending upon the user’s preference, messages that are recognized as spam are deleted without showing them to the user, forwarded to another address, or rewritten so the subject line contains a tag identifying the message as spam.

A company that provides this service would find a large number of users willing to pay a monthly fee in order to have mailboxes with greatly reduced spam counts.

Adam Kalsey
June 15, 2002 11:23 AM

I've discovered a service that meets many of the requirementrs we laid out here. Read Spam Filter Redux:

October 15, 2002 4:15 AM

SpamCop also seems to meet most of your requirements

Adam Kalsey
October 15, 2002 8:46 AM

I'm familiar with spamcop, but it doesn't meet the primary requirement. The service in question must be easy to use. Not easy for me, but easy for a non-technical user who doesn't understand email at all. Someone for whom setting up Outlook Express was a challenge. Spamcop requires that you get your ISP to forward mail to them and then you need to change your mail settings so that you collect mail from their server. And you have to configure mail settings like "reply-to" so that you can still use your own email address. Spamcop doesn't allow you to determine which filtering rules to apply. In fact, it appears to rely entirely on its own database of known spam for filtering.

November 5, 2003 4:17 PM

it takes time for people to delete spam mail, i usually have 15 spam mail come though my email per day even having anti spam software.

Jason Short
December 19, 2004 3:52 PM

We actually perform this type of service for people who own a domain (sorry, not for individuals). You only change your MX records to point to us, and we filter it all and send clean email down to your existing mail server. NO changes to your clients at all, no changes on the server in most cases.

January 6, 2005 11:26 AM

Hi, I am currently developing a very similar idea to what you suggest here... will allow individual users to use our service with only a simple change in their e-mail client - with no extra software required... ease of use is the key here - plus as an added benefit the service works on any platform! As well as a rules based filter, we have our own unique method of stopping unwanted e-mail (Full details soon to be released!). Get in touch if you are interested! Dan

Marc Perkel
March 17, 2005 5:49 AM

Here's a reall good article on advanced spam filtering techniques that are used buy Junk Email Filter who does front end spam filtering the way you suggesterd here. It inclueds a lot of tricks to reject spam before it has to go into Spam Assassin.

June 12, 2005 1:13 PM

NuXo Technologies Filtering Services allow exactly that, focusing on Advanced Context Filtering and making fighting spam and virus very simple for the customers.

Ron Reeves
September 15, 2005 2:50 PM

We have developed a solution for domains similar in scope to others mentioned here where the user points their MX record to us, we filter Spam and viruses and relay the email back to them. We started offering this out of necessity for our hosting clients in 2002 and it has grown into it's own product ( and evolved into a very effective solution. One of the keys for us was being able to scale this to handle the millions of messages a day we filter and do it across two data centers that are geographically diverse - while at the same time giving the user an easy to use web interface to control all aspects of their filtering and routing. We took this route with our existing clients back in 2002 because they wanted a solution that we managed, not them. It is now a full time job for 10 support, sales, programmers and network folks but we leverage it across tens of thousands of mail boxes.

February 12, 2006 6:12 AM

Some of the solutions posted here aren't so good for individuals wanting to get email from their domain. Emerald Shield starts at 10 email addresses, starts at 25 email addresses, and Nuxo appears to hide its pricing altogether.

February 12, 2006 6:14 AM

Some of the solutions posted here aren't so good for individuals wanting to get email from their domain. Emerald Shield starts at 10 email addresses, starts at 25 email addresses, and Nuxo appears to hide its pricing altogether. Here is a list of similar services:

February 17, 2006 7:13 AM

salam man shantiyam

June 9, 2006 9:48 AM


I Hate Spam
October 9, 2006 6:49 PM

Funny looking back and seeing this thread. Spammers and spam fighting technology has come a long way. The bad thing is I see more spam now than at any time. I'm a big fan of Barracuda, they have the best interface and their product works really well once you train and tweak the filer.

May 25, 2007 11:40 AM

I believe the only way to eliminate spam problems completely (at least most of the time) is to reduce the possibilities to use the internet anonymously. This should be performed in any other activites online, for example when opening acccount in free web hosts, etc. I get 100 spam emails everyday. Not too many, but I have to spend at least 30 minutes everyday to remove them and to allow legitimate emails.

This discussion has been closed.

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