Six Primary Levels of Filtering

SpamStopsHere uses six primary and several additional levels of filtering to accurately and completely filter all types of spam. These levels are briefly described in this section and in more detail later on this page.

The first level called the "URL/Phone # Filter" is the heart of our service. It is a database of all the "Click me" links (URLs) and "Call me" phone numbers found in recent spam messages. It is updated every 10 minutes and receives about 1000 additions per day.

By itself, the URL/Phone # Filter blocks over 95% of spam and is so unlikely to block a legitimate email (less than 1 in 100,000) that most customers find it unnecessary to review emails filtered by this level.

The "Phrase Filter" is a database of distinctive phrases (typically entire sentences) used in recent spam. For example, while our service won't ever block an email that references "Viagra" numerous times, the Phrase filter will block e.g. "Cheapest Viagra on the Net". These phrases are carefully hand-selected by our staff to ensure that they would never occur in a legitimate email.

The "Pattern Matching Filter" is a (small) set of rules to catch HTML tricks and other techniques used only by spammers. (E.g. a URL with an IP address encoded in hex characters.) We only employ rules which we are very confident will not block legitimate emails.

As shown in the following table, these first three levels of filtering catch nearly all the spam blocked by our service. They are so unlikely to block a legitimate email (less than 1 in 100,000), that few customers review the spam blocked by these levels.

• URL/Phone Filter - 95.0%
• Phrase Filter - 95.0%
• Pattern Matching Filter - 0.5%
• Country-Of-Origin - 0.5%
• Additional Filtering - 0.5%

The "Additional Filtering" is an additional (small) set of rules that each customer can enable/disable according to their preferences. The rules are organized into "Recommended", "Optional" and "Aggressive" categories. For new customers, only the Recommended filters are enabled by default. The Optional category includes blocking all emails that are in Chinese, Korean or Russian.

To view the current Additional Filters, use the following link to go to the demo Control Panel, then click on Configuration Options; and then click Edit next to "Additional Filter".

About a dozen countries, including China, Brazil and Argentina, are notorious for sending spam. The optional "Country-Of-Origin Filter" can block all email originating from these countries. Some customers review the spam which is blocked by this level and/or create Whitelists of their contacts in these countries. You can select which countries, if any, to block.

Realtime Blacklists (RBLs) are databases, maintained by other anti-spam organizations, of the IP addresses of mail servers which are known or suspected of sending spam. The optional "RBL Filter" uses several different RBLs, including SpamCop (tm) and Spamhaus (tm). You can select which RBLs, if any, to use for filtering. Since the RBLs may block an occasional legitimate email, many customers review only the spam blocked by the Country-Of-Origin and RBL filtering levels.

The URL/Phone # Filter and Phrase Filter are designed to block nearly all spam using databases that are constantly updated by our tools and staff. The Phrase Filter and optional Country-Of-Origin and Realtime-Blacklists (RBLs) filter levels are useful for catching brand new spam campaigns before our tools and staff add their URLs and/or Phrases to our databases.

As an additional filtering level, SpamStopsHere maintains a modest-sized database (IP Blacklist) of mailservers that are known to send spam, that are outside of the US and Canada, and which are probably owned by spammers. This is similar to a RBL, but the IP addresses are carefully researched by our staff.

Reviewing Spam

Corporate customers find SpamStopsHere so accurate that most don't review anything blocked by our service! Nonetheless, for each level of filtering you can:

• Forward the (likely) spam to a review mailbox at your domain. This is typically a mailbox such as spam@yourdomain.com.
• Change the subject line to tag it as spam.
• Send a customizable rejection message back to the sender.
• Completely delete it without notification.

If you choose to review spam, it is generally only necessary to review those blocked by the Country-Of-Origin and RBL filtering, which is less than 2% of the total spam. For example, if your organization receives 1000 spam per day, the last thing you want to do is review 1000 spam; even if you tried, you would most likely miss a legitimate email in the middle of all the spam. However, by setting the first three filter levels to "Delete" and only reviewing the remaining levels, you would only need to review about 20 spam emails a day.

Once new customers are familiar with our service and verify its accuracy, most prefer not to review any spam. We then recommend the following filter level actions:

Special Mailboxes

As mentioned earlier, spam can deleted, rejected, tagged or forwarded to a review mailbox such as spam@mybiz.com. This lets you check the operation of our service and double-check if any legitimate email was blocked. Click here for more information.

You can also specify one or more "bypass" mailboxes; any email sent to these email addresses will never be blocked. For example, if you have a few clients in countries you have chosen to block, they can contact you via these special email addresses. If you pick an unusual email address and only reveal it to trusted clients, it should be reasonably free of spam for a long time. (Note: Don't list your bypass email addresses on your website, unless you use JavaScript, or they will quickly start receiving spam.

You can use a "bypass" mailbox as part of your rejection message when you have at least one filter level set to "Reject" spam back to the sender. For example, the rejection message could read:

We are sorry that your email to vedit.com was blocked by our anti-spam service. You can either resend it to the special email address salesx4@vedit.com or call us at (734) 555-1234.

You can easily set up and change the spam and bypass mailboxes from the Control Panel.

Whitelists and Blacklists

While our service requires no "tuning" or "learning", and is unlikely to block legitimate email, you can ensure that important clients and contacts are never blocked by adding them to your domain-specific Whitelist. This is especially useful if you have a few clients in countries that you mostly want to block.

For example, some of our customers have many contacts in China. They have chosen to add these contacts to their Whitelist and otherwise block all email from China.

You can whitelist by email address, domain name, IP address or content.

To further reduce the chance that mail from legitimate companies is blocked, we maintain a Global Whitelist for all customers. Companies with large customer mailing lists sometimes get blacklisted just due to their volume of email. We add these and other reputable companies to the global white-list. We will gladly consider customer suggestions, which can be submitted from the Control Panel.

The custom Blacklist can be used to, e.g., block someone who is harassing your employees. Or you might want to block recruiters, mailing lists or anyone else that you don't want contacting your employees. You can blacklist by email address or by IP address.

We prefer that customers not attempt to block any remaining spam themselves (unlike other anti-spam systems). Instead, it should be forwarded to us and our staff will immediately create the most appropriate filter for it.

The "Custom Content Filtering" can handle any special needs. For example, if your company makes a product called "MasterWidget" you can add a Whitelist filter to accept any email that contains "MasterWidget" anywhere within it.