Dealing with spam

E-mail has become an indispensable communication tool at University, as everywhere else. However, there is a problem with the significant amount of spam (unwanted) messages being sent to e-mail users every day.

Most of these messages have a commercial focus - promoting or selling products or services. However, spam mail includes messages promoting fraudulent schemes (e.g. pyramid selling and get rich quick schemes) and offensive content (e.g. pornography).

Undoubtedly, this mail is a growing nuisance for e-mail users and is also disturbing especially when its content is offensive. Also, spam consumes valuable resources including storage space in the user's mailbox.

In response to the growing problem of spam, early last year the University Computing Services Centre (CSC) initiated a project that aims to minimise the negative effects of spam mail on university staff and students.

The project has two main aims:to implement a mail filter program on the CSC mail servers to help staff and students manage spam mail more effectively; and to raise a campus-wide awareness of the spam problem and to provide guidelines to individual e-mail users on further actions that can be taken from their side to minimise spam.

SpamAssassin, first installed on the CSC mail servers on a trial basis, scans incoming messages and uses a variety of techniques to identify potential spam. Each message is assigned a score value based on the analysis made. If the score is higher than a particular value the message will be classified as 'spam'.

CSC staff also developed a Web interface for users to be able to switch on the spam filter facility, to configure the sensitivity of the filter, and to set their specific e-mail address whitelist and blacklist.

Initially, the spam filter facility simply tagged messages classified as spam but these were still delivered to the recipient's mailbox along with other genuine mail. Users could perform further filtering of such e-mails by setting filter/message rules on their e-mail client program e.g. to direct spam-labelled messages to a separate e-mail folder.

During last year's trial phase, CSC was monitoring the functionality of the spam filter and evaluating feedback sent by users. Most users indicated that the spam filter was helping them deal better with 'spam mail'. Some users suggested that messages classified as 'spam' should simply be deleted at server level rather than being labelled and delivered along with the other incoming mail.

The CSC has always been cautious to minimise interference with users' e-mail. Simply deleting spam mail at server level raises two issues. First, the filter program may occasionally classify a genuine message as 'spam'. Also, what constitutes spam mail for one user may not necessarily be so for another user.

To address these issues the CSC has launched an enhanced spam filter facility. Users can enable the spam filter and choose not to have spam mail delivered to their mailbox. Such messages are blocked and stored on the CSC server for 14 days. Users receive a daily e-mail report listing details of the quarantined messages and they can retrieve any of these blocked messages anytime within the 14-day period.

More information on the CSC spam filter facility, as well as general guidelines on dealing with spam, are available at: www.csc.um.edu.mt/ email/spam/