User guide

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6.4.4.2 Whitelist
In general, a whitelist is a list of items or persons who are accepted, or have been granted permission. The term
“email whitelist“ defines a list of contacts from whom the user wishes to receive messages. Such whitelists are
based on keywords searched for in email addresses, domain names, or IP addresses.
If a whitelist works in “exclusivity mode“, then messages from any other address, domain, or IP address will not be
received. If a whitelist is not exclusive, such messages will not be deleted, but filtered in some other way.
A whitelist is based on the opposite principle to that of a blacklist. Whitelists are relatively easy to maintain, more
so than blacklists. We recommend that you use both the Whitelist and Blacklist to filter spam more effectively.
6.4.4.3 Blacklist
Generally, a blacklist is a list of unaccepted or forbidden items or persons. In the virtual world, it is a technique
enabling acceptance of messages from all users not present on such a list.
There are two types of blacklist: Those created by users within their Antispam application, and professional,
regularly updated blacklists which are created by specialized institutions and can be found on the Internet.
It is essential to use blacklists to successfully block spam, but they are difficult to maintain, since new items to be
blocked appear every day. We recommended you use both a whitelist and a blacklist to most effectively filter
spam.
6.4.4.4 Exception list
Exception list usually contains email addresses that may be spoofed and used for sending spam. Email messages
received from addresses listed in the Exception list will always be scanned for spam. By default, the Exception list
contains all email addresses from existing email client accounts.
6.4.4.5 Server-side control
Server-side control is a technique for identifying mass spam based on the number of received messages and the
reactions of users. Each message leaves a unique digital “footprint” based on the content of the message. The
unique ID number tells nothing about the content of the email. Two identical messages will have identical
footprints, while different messages will have different footprints.
If a message is marked as spam, its footprint is sent to the server. If the server receives more identical footprints
(corresponding to a certain spam message), the footprint is stored in the spam footprints database. When scanning
incoming messages, the program sends the footprints of the messages to the server. The server returns information
on which footprints correspond to messages already marked by users as spam.