what is the spam filtering implemented by aplus.net concerning shared hosting plans?

Aplus.Net currently offers three levels of SPAM filtering for customers who have subscribed for shared hosting plans. These are two SPAM filters and the Greylist service:

I. The first SPAM filter uses the MAPS-RBL database with server addresses that are known to send SPAM. It is enabled by default for all customers and there is no configuration needed for it. The database is updated constantly. If the IP address of the sending email server is listed in the MAPS database as a known SPAM source, all email messages sent from this server to Aplus.Net’s network will be rejected.

II. The Greylist service.

With the Greylist service, Aplus.Net’s mail system will not deliver any message unless it has logs of a previous attempt to send the same message, by the same server. This may cause delays when sending emails to a particular email account for the first time. The Greylist service is a relatively new method for combating SPAM and is very effective. It is activated by default for all shared hosting plans and there is no configuration needed for it. Please refer to the documents below for a detailed explanation of the Greylist service:

• How does the Greylist service work?

III. The second SPAM filter adds flexibility and effectiveness in fighting unsolicited emails coming from new sources which are not listed yet in the first filter’s database. It examines the content of the email itself and evaluates several indexes, instead of just checking the sender email address. This SPAM filter is not enabled by default and has to be configured individually for each of your email boxes. Please refer to the document below for detailed instructions:

• How do I setup the SPAM filter for my email accounts?
• How do I make a list of contacts in my webmail that will automatically pass through the SPAM filter?