Weekly Tech Topic (Spam)
Continued from home page:
With greylisting three pieces of information are obtained every time an email is received by a server. These pieces include the Internet Protocol (IP) address of the sending mail server, the sender's email address, and the email address of the recipient. These three elements are saved in a database where a check is done to determine if a combination of the three elements has been received on any other occasion.
If the combination has been previously seen then the email is accepted. However, if it has not been previously received then the sending server is asked to retry at a later time. Legitimate email servers have no problem processing this request. However, many of the mass emailing tools used by spammers will not resend the message.
Another powerful tool for combating spam is SpamAssassin. This software tool analyzes the contents of a message to determine whether it has certain characteristics that indicate it might be spam. Different weights are assigned to the various characteristics and an overall score is assigned to the message. If a message's score is above a certain threshold, then it is deemed to be spam.
Connected IT Solutions, LLC utilizes both greylisting as well as SpamAssassin in its effort to combat spam. These checks can be enabled or disabled on a per email address basis. Messages that are tagged as spam by SpamAssassin are placed in a Junk Email folder so the owner of the email address can verify that all of the messages were indeed spam.
More information on greylisting and SpamAssassin can be found by clicking on the following links:
- Greylisting: http://en.wikipedia.org/wiki/Greylisting
- SpamAssassin: http://en.wikipedia.org/wiki/SpamAssassin