BitDefender AntiSpam (Win SMTP Proxy) uses six proprietary modules to keep unwanted e-mail out of your organization:

- IPMatch
- Keyword Filter
- White List/Blacklist
- Charset Filter
- URL Filter
- Heuristic Filter

BitDefender AntiSpam checks every incoming & outgoing email message and attaches a Spam Score. If the spam score is greater than or equal to the spam threshold, then the message is marked as spam. Otherwise, it's marked as ham (non-spam).

For complete protection, BitDefender AntiSpam can also be installed along with BitDefender for Exchange 5.5 and BitDefender for Lotus Domino.

BitDefender AntiSpam should not be installed along with BitDefender for MS Exchange 2003, BitDefender for MS Exchange 2000 or BitDefender Antivirus & Antispam for Mail Servers (WIN SMTP Proxy), because all these products already provide both antivirus and antispam protection.

IPMatch
This feature matches a specific e-mail address to a specific IP. Thus, spoofed e-mail headers are no longer enough to fool a white list. If the IP address doesn¡¯t also match, the message is rejected.

Keyword Filter
A content filter is implemented "before" the AntiSpam filter. Relevant categories are message subject, headers, body and address fields. A set of explicit allow/don¡¯t allow rules must be defined. If and only if a particular piece of mail passes through the content filter does it reach the AntiSpam filter.

WBL (White List/Blacklist) support
This quite simply means that the admin can set a list of trusted and untrusted addresses from which to respectively "always accept" or "always reject" mail.

Charset Filter
The Reject char sets option will cause all the e-mail messages written in Cyrillic and/or Asian char sets to be rejected.

URL Filter
Most of the spam messages contain links to various web locations (which contain more advertising and the possibility to buy things, usually). BitDefender has a database which contains links to these kinds of sites. Every time you perform an update new links will be added to the URL filter; this will help increase the effectiveness of your AntiSpam engine.

Heuristic analysis technology
The heuristic filter performs a set of tests on all the message components, (i.e. not only the header but also the message body in either HTML or text format), looking for words, phrases, links or other characteristics of spam.

Fully configurable reactions.
- Mail tagged to be spam can be sent to a valid, admin-set address, for periodic checking;

- The score returned by the AntiSpam library can be appended to the mail subject line. This is only done to mail which exceeds the spam threshold;

- An attribute indicative of confidence level can be added to the header;

- Mail tagged as spam can be rejected (SMTP error 550) or dropped.

Detailed reports and statistics
BitDefender AntiSpam comes with a separate reports module which provides daily, weekly or monthly statistics organized by categories. The reports can be generated and viewed in the console, or can be saved as text files or html.

Automated Update
Updates to the AntiSpam engines are free and fully automated. Checks for updates can be scheduled to take place as often as necessary.

System requirements:
- Pentium II processor - 400 MHz
- RAM: Minimum 128MB
- Minimum 20MB available hard disk space (50MB Recommended)