Our anti-spam countermeasures can be divided into two types: pre-acceptance and post-acceptance. Pre-acceptance methods are used before our systems accept an e-mail—if the check fails, you do not receive the e-mail. Post-acceptance methods are used after a system accepts an e-mail—if the check fails, it will be marked as spam and placed into your inbox’s “Spam” folder.
The pre-acceptance methods we use include:
- realtime blackhole lists
- greylisting
- SPF DNS record checks
For post-acceptance spam filtering, we use SpamAssassin and Bogofilter.
If you are only forwarding mail to an e-mail account hosted elsewhere from Rhombic Networks, e-mail will only go through pre-acceptance checks. If your mail arrives to a Rhombic Networks-hosted Inbox, it will also go through post-acceptance checking.