You probably know from before that Halon’s scriptable SMTP server enable email providers to avoid blacklisting and increase deliverability. The 4.6 release, “curry”, contains Cyren’s outbound anti-spam (OAS). In combination with our cluster-synchronised rate limit function, it provides incredibly effective and accurate abuse prevention. Just like their Cyren’s inbound anti-spam, OAS uses a hash-sharing technology called recurrent pattern detection (RPD) that identifies outbreak patterns. It’s designed to detect spam from internal sources rather than external, and doesn’t report/contribute any signatures since it could blacklist your own infrastructure.

With the flexibility of scripting you can determine customer/sender identities accurately even in mixed traffic. This is used as identifier for rate limits based on classifiers such as Cyren’s OAS, delivery failure rate, queue size, etc. By using IP source hashing and alternative IPs for suspicious traffic, deferring obvious abuse and controlling connection concurrency, you can achieve high deliverability with minimal administration.

The 4.6 release comes with many additional features and improvements. It adds SNI support to the TLS functions. The Monaco-based code editor now have additional code completion, built-in documentation, tabs, and a mini-map.

For more information on the release, see the full changelog on GitHub. If you want to try Cyren’s outbound anti-spam, contact our sales team.