ASSP relays the SMTP dialog between an incoming client and your SMTP server, intercepting the dialog as needed. ASSP performs a number of configurable spam checks and on detectinga spam message provides an immediate 5xx SMTP error code back to the client. ASSP offers: a whitelist of known good senders Bayesian checks on message headers and contents local user validation using RFC822 checks flat lists or LDAP lookup relay denial, HELO checking, SPF (Sender Policy Framework) checking, DNSBL (DNS Block List) checking using many block list services delaying of messages from unknown senders Virus detection.
Features of Anti-Spam SMTP Proxy Server
- Multiple Weighted DNSBLs
- Multiple URIBLs
- Greylisting
- Weighted Regular Expression Filtering
- Bayesian
- Penalty Box
- SenderBase
- SSL/TLS
- SPF/SRS
- Attachment Blocking
- ClamAV and FileScan
- Blocking Reporting
- LDAP support
- Backscatter Detection
