Mail security and SMTP filtering
Dedicated AntiSpam SMTP proxy for business email
The dedicated AntiSpam SMTP proxy is designed as a protective layer in front of a company mail server. It analyses SMTP sessions, sender reputation, DNS signals, message content and user patterns before mail reaches internal mailboxes, reducing spam, phishing, malware delivery attempts and brute-force abuse without forcing the company to replace its existing mail platform.
SMTP proxy before the mail server
The gateway can sit in front of Zimbra, Exchange-like, IMAP/SMTP or custom business mail systems and decide whether to accept, reject, defer, tag or quarantine messages before they reach user mailboxes.
DNS, reputation and sender identity
Filtering can combine MX, SPF, DKIM, DMARC, reverse DNS, HELO/EHLO, TLS, ASN, IP reputation, DNSBL/RBL and more than 1000 DNS-related and delivery parameters.
Heuristics, language analysis and ML
The service combines content heuristics, language analysis, Bayesian classification, Hidden Markov Model scoring and adaptive learning from user behaviour instead of relying on one static blacklist.
Custom rules and abuse blocking
Per-domain policies, allow/block lists, scoring rules, attachment rules, rate limits, greylisting and brute-force protection can be adjusted for the organisation's real mail traffic.
Decision signals
Best fit
companies running their own mail server, Zimbra, collaboration platforms, accounting systems, ticket systems and high-risk public mailboxes
Core functions
SMTP proxy, antispam, phishing reduction, DNS analysis, language heuristics, custom rules, quarantine and logs
Security controls
Bayesian scoring, Hidden Markov Model scoring, user-adaptive learning, brute-force blocking, rate limits and abuse monitoring
Search intent
SMTP anti spam proxy, dedicated antispam gateway, mail security service, spam filtering for business mail server
Related services
Related guides
Frequently asked questions
Is the AntiSpam SMTP proxy a replacement for the mail server?
No. It is a filtering and security layer in front of the mail server. The existing mail platform can remain responsible for mailboxes, webmail, calendars and storage.
What does the DNS analysis check?
The gateway can evaluate MX, SPF, DKIM, DMARC, reverse DNS, HELO/EHLO, TLS, IP and ASN reputation, DNSBL/RBL signals and many additional DNS-related delivery parameters.
Can we define our own rules?
Yes. A dedicated deployment can include domain-specific allow/block lists, scoring rules, attachment policy, quarantine policy, rate limits and exceptions for business systems.
How does adaptive filtering work?
The service can learn from user and administrator decisions, combining Bayesian scoring, Hidden Markov Model scoring, language analysis and operational feedback from real mail traffic.