Email Spam Explained

Spam 101
Are you tired of getting spam? We all are, in fact there is a booming business on fighting spam such as spambully.com. They filter out mail that comes to you, forward mail to your phone. Their program lets you create a white list of people who can send you mail. You can create challenge emails so that people send you mail can verify that they are human and then you receive the mail. This integrates with Outlook and Outlook Express and can help alleviate some of the headache you space from spam.

What is Spam?
Spam by definition is "unsolicited email". That means any mail you did not request or from someone you don't know. If you sign up for a newsletter and they send you mail then that would be called an opt-in list, meaning you gave them permission to send you newsletters and other types of email, and the would need to provide a link for you to "opt-out" at any time from their newsletter or email system.

Point System Spam
Spam works on a Point System, for instance a person sends out 5,000 emails with the same subject, and content this email would receive a high Spam Point by whatever spam blocking agent is located on the mail server such as
spamassassin.apache.org Spam assassin can be set to take all spam and send you a message about it or put it into a default mailbox typically referred to as the "black hole". If the same guy sends out one message at a time changing each message in a different way then these emails would be assigned a low Spam Point and most likely get through. Now is this message was sent to multiple accounts on the same mail server it would generate a higher Spam Point and most likely be blocked as Spam.

Mail Spoofing
Have you received email stating "Sorry but i could not deliver your message to the mailbox", but can never remember sending such email at all and upon looking at the email noticed that it was spam but you never sent it ? This is called E-Mail spoofing. It means someone sent email and made it look like it came from you. You would have never known about it unless someone sent you an email saying stop sending me spam. The message above is called an NDR a "non deliverable report" meaning that the email address to send the mail to could not receive the email for one reason or another.

Foreign Country Block
Email-filtering companies say foreign-language spam has risen sharply in the U.S. in the past year. Symantec estimates that 10% of the 200 million spam messages its software catches each day are in a foreign language, up from about 5% just two years ago. Sophos Plc, a privately held U.K. rival, says Japanese spam has grown tenfold since January. Postini Inc., of San Carlos, Calif., says its software blocks about 20 million messages a day in Chinese.

Spam Authority
There are many companies that try to be the authority on spam. A few examples are
http://www.spamhaus.org/ or spamcop.com. The problem with companies trying to be the authority on spam is clear in the following example:



John Doe has a mailing list in which people sign up for his monthly newsletter when they register, the mail comes from This email address is being protected from spambots. You need JavaScript enabled to view it.. When people sign up for the mailing list they do not let the authority they are using to protect their mailbox from spam know this. The next time Michael sends out an email he gets marked as Spam from spamcop.com even though his list is an opt-in list. The way spamcop works is, if you send a message to a person Spamcop sends you a message back saying "your not on my white list please confirm you are human then we will send your message." Michael is not checking the mailbox for This email address is being protected from spambots. You need JavaScript enabled to view it. and never responds to spamcops request, so he gets marked as spam. This could have been avoided one of two ways. The person signing up for the newsletter needs to add This email address is being protected from spambots. You need JavaScript enabled to view it. to the white list with spamcop. Michael also needs to monitor the mailbox This email address is being protected from spambots. You need JavaScript enabled to view it. and respond to request for verification from authorities such as spamcop when it was received. If you are sending out mass emails and they are legit, then you should monitor the mailbox they are being sent from for NDR (bad email addresses) and Spam Authority requests such as the one sent by SpamCop in this example.

Spam Filter Program Example - Spamalizer
Here is how a typical Spam filter program works. It scans every email and assigns some grade to it.

An email can get from 0 to 10 points.

Emails assigned 0 - 3.5 points are being delivered to your mailboxes without
any changes, they are not spam.

Emails receiving up to 6 points are marked as [SPAM] and will be delivered into
your mailbox as well. They are PROBABLY spam. If you want you can configure your local mail client to move them into a separate folder automatically.

Emails receiving up to 7 points are moved to a quarantine mailbox on the spamalizer server and it sends a notification to you with a link to the blocked message. You can log in by using the link to spamalizer and check the message blocked.

And emails receiving more then 7 points are definitely spam and they are deleted
automatically. 7 points is a very high value, we tested the system on many thousands emails and it didn't delete any non-spam message.