USD-457 Email Spam Policy
The purpose of this page is to give a brief explanation of what Spam is and how junk email is blocked in Unified School District 457. Email webmaster@gckschools.com if you have questions that are not answered on this page.
For people in USD-457, if you receive a spam message that gets through our filters, please forward it to spambuster@gckschools.com We will continue to create new filters and ways of blocking that spam that leaks through our system.
Spam is unsolicited commercial email that is unrequested and unwanted. It is usually sent to multiple users with the intent of promoting a business venture or service. Usually these emails contain advertising for tacky Internet sites, products of dubious quality and get-rich-quick schemes.
It is the general policy of USD-457 that we do not want to deliver this type of undesirable email to our users, therefore we are taking steps to eliminate it.
Spam Rules
A Spam Rule scans the header information of emails to determine which emails are junk. It can see who the email is from, who it is sent to, what the subject is and what domain it is in. Our system has three rule-sets used to scan email.
1) Address Filters - These are the email addresses of known spammers that have sent spam before to USD-457. Because spammers change their addresses and use fake addresses, this rule is the least effective rule used to block spam.
2) Trend Micro Rules - These are rules created by Trend Micro Systems. They are updated every few weeks and block emails based on the sender/recipient. Emails addressed to Undisclosed Recipients or Bulk Recipients will be blocked by this rule.
3) User Made Rules - These are rules created by USD-457 Technology that block emails based on words in the Subject line of the email. Most of the words that are searched for are commonly used by spammers. Such words include Refinance, Mortgage Quotes, Free Insurance, etc.
Spam Filters
A spam filter is like a rule, but it searches through the entire contents of an email including the body or message of the email. Filters can search for an entire phrase, or a combination of words scattered throughout the email. The keywords it searches for are not case-sensitive and the entire word must be found for a match to be made, words within words such as gRAPEfruit are not counted. Our system uses a variety of spam filters.
1) Hoax Filter - This filter searches for common fake virus warnings and hoaxes. Examples of keywords it looks for are "A virutal card for you" and the words "AOL4FREE" and "virus" in the same email.
2) Chain Mail Filter - This filter searches for common phrases that are associated with Chain Letters. Chain Letters are usually emails that serve no other purpose but to be forwarded (spammed) to as many people as possible. Examples of phrases it looks for are "forward this to all your friends" and "this is not a joke"
3) HTML script filter - This filter is meant to block potentially harmful spam email that is sent with scripts in the body. Examples of what it looks for are "<html>" "<script" "</script>" and "text/html" all in the same email
4) Melissa Virus filter -This filter searches for the Melissa virus that may or may not be found by the Virus Scanner program. The Melissa virus will usually have certain words in the email that are scanned for such as "Melissa.U" and "Melissa.V"
5) Pornographic Spam filter - This filter is made by USD-457 Technology to target spammers that send pornographic material. This filter will block emails based on combinations of keywords that appear in such emails, such as "live" "nude" and "shows" all in the same email or the phrase "caught on camera"
6) Business Spam filter - This filter is made by USD-457 Technology to target spammers that send unwanted spam promoting their businesses or trying to find victims for a scam. Many spammers will include telephone numbers, email addresses and street addresses in their spam mail. We search for this information in spam email that our users report. Some examples are "GenuineRewards", "Box 202885,Austin,TX 78720" and "1-786-666-5155"
7) Trend Micro's Anti-Spam filter - This is list of Spammer addresses, names, phrases and keywords created by Trend Micro. The company collects this information from their customers and updates it everyday to include the latest information. An example is the url "http://clicktrac.com/ct.cfm" located anywhere in the email.
8) Spam Phrase filter - This filter is made by USD-457 Technology to catch key words and phrases that are commonly used by spammers in their propaganda. Many spammers will use form emails to send out spam, so the wording of their mail will not change very much. By targeting these words, we can reduce the number of overall spam email. Some examples are "rebuild your credit", "absolutely free" and "guaranteed" in the same email and "settle your debt"
9) Known Spammers filter - This filter is made by USD-457 Technology to catch known spammers based on emails they have sent out before. This filter takes links directly from a spam email, usually links that point to Unsubscribe here or Click here to learn more. It can also be a certain picture the spammer always uses. These are links that form the purpose behind the spam, as the spammer will not make any money if you don't visit them. By blocking the links these spammers use, we avoid blocking innocent mail and catch the repeat spammers. Some examples are http://the-netsource.com/remove.htm, and http://netflip.com/mailimg/f/B-TL.gif
10) Website Spam filter - This filter is made by USD-457 Technology to catch known spammers based on emails they have sent before that have a link to a website. Many spammers of online companies include a website for you to visit. This filter will look for those websites who have sent us spam in the past and block emails that contain links to them. Some examples are "Gotlaughs.com", "www.coolfreecard.com", and "www.hghsource.com"
