IT Services offers server-side filtering for unwanted email or spam. Users with a University email address can manage spam messages more efficiently using this spam filter facility. This system does not involve installation of software on the user's computer system.
By default, the spam filter facility is enabled. Users are instructed to read through the following information and the content of the Web pages indicated at the end of this page, before disabling the spam filter.
Features of the Spam Filter
- The software scans incoming messages, looking for specific words or phrases (spam signatures) which are known to occur in spam. Each message is assigned a score (point) value based on the identified spam signatures. If the score is higher than a particular value known as the threshold value, the message will be classified as 'spam'.
- The scanning of messages is an automated process done entirely by the spam filter program on the University server. It does NOT in any way involve a person/s reading any other person's email messages! The spam filtering software being used on University mail servers is SpamAssassin.
- The spam filter (when enabled) will not deliver spam messages to the recipient's mailbox. Spam messages are blocked and stored on the University server for 30 days. Users will receive a daily email report listing the details of the quarantined messages. The recipients are able to retrieve any quarantined message stored on the University server to their mailbox.
- Users can also specify a list of email addresses known as a blacklist. Messages sent from blacklisted senders are blocked and stored on the University server.
- Users can also specify a list of email addresses known as a whitelist. Messages sent from whitelisted senders are not classified as spam, even though these may have spam content.
- The sensitivity level of filtering or threshold value may be customised by users as appropriate. Low threshold values will classify more messages as 'spam'. However, users should be cautious about low threshold values because most of their genuine mail will end up blocked by the spam filter.
Messages originating from the campus network passing through the University mail servers are never classified as 'spam'.
- The spam filter deletes messages with a score (point) value above 20. Other messages with score values between the threshold (set by the user) and 20 are blocked and stored on the University server. All blocked emails can be retrieved from the University server at any time within 30 days. Blocked messages are deleted from the University server after 30 days.
The spam filter may occasionally classify a legitimate and potentially important message as 'spam'; a so called 'false positive'. Accordingly, it is the responsibility of the user to routinely review the daily email report listing the quarantined messages.
It is important to note that the University spam filter service is just a part of the effort required to help users deal with spam. Users are also encouraged to follow the anti-spam guidelines indicated here.
Queries about the spam filter facility should be directed here.
19 May 2013