Below are some basic definitions and examples of the powerful filtering and anti-spam procedures that we use to help keep your inbox free from junk mail. Although we do everything we can, no provider can ever guarantee that you will be 100% SPAM-free unless you completely restrict the allowed inbound email domains, which is an available option for our Student-Safe mail.
Bayesian filtering is a method of spam prevention. It operates by rating the probability of incoming mail being spam by looking at words or character strings contained in the email as well as the entire context of the email. Bayesian filters can be 'trained' to identify spam by building up libraries of 'good' and 'bad' mail (spam). There is also the ability to "auto-train" the Bayesian dictionary. This means the filter is continually improving by 'learning' to identify spam and good mail based on emails that are passing through the server.
Use message filters to search messages for words or phrases and delete or quarantine them before they are delivered to the user. Mark messages as spam so that they are placed directly into the recipients Junk Mail folder.
Filters can also be configured to move or delete messages based on content and much more.
Without relay control, spammers can utilize your server in order to send out their junk mail, making it look as though you were the origin of spam. MailEnable has inbuilt relay control that prevents your server being used as a relay for spam.
Reverse DNS Blacklisting
Reverse DNS Blacklisting allows you to validate those sending mail against a list of potential spammers. You can select which Real Time Blacklists (RBL's) providers you want to use. You should enable only the providers that you need, as this does impact performance. You should also review which providers are most appropriate by reviewing their web sites.
Sender Policy Framework (SPF)
Sender Policy Framework (SPF) prevents the 'spoofing' or forging of mail addresses and makes it easier to identify spam, worms and trojans.
SPF requires a DNS record to specify which machines are authorized to transmit mail for that particular domain. Therefore the mail server receiving mail can determine whether a message came from a domain other than the one claimed by the sender.
Greylisting helps reduce spam by delaying messages for a short period of time when the sender is not someone who has recently sent to that destination. A large percentage of spammers do not retry sending a delayed message, but normal mail servers will, so the message will come through on the next attempt.
URL Blacklist Content Filtering
The MailEnable SMTP Connector scans the content of messages as they are received and can identify whether the contents of the messages contain offensive URLs by looking up their IP address against DNS blacklist providers.