Spam Filtering

Peace and Quiet

Spam is the bane of Internet life, creating a huge nuisance for many companies as it chokes mail servers and litters inboxes with distracting, useless, and often offensive messages. For our Network Freedom™ customers, however, spam is a thing of the past, and our new customers are often shocked by the sudden silence that ensues when we enable our email filtering solution for them. Email becomes a useful tool again.

Multi-Faceted Approach

We employ a standardized, multi-faceted spam-filtering solution for all of our customers. We route all of your incoming email through our filtering system before forwarding it onto you. We process over 3 million email messages a month, fully 95% of which are spam, with an error rate of much less than 1%. Our system uses multiple techniques to filter out unwanted email, including:

• Blacklisting: Checking the sending server against a list of known malicious servers.
• Recipient Filtering: Checking for a valid recipient before accepting a message.
• Spambot Greylisting: Rejecting messages from zombie "spambot" computers.
• Virus Scanning: Scanning the message for viruses.
• Content Analysis: Analyzing the actual content of the message for spam-like patterns and keywords.

Hands-Free Filtering

Our system requires no human intervention; there is no "quarantine" that you have to check periodically. This is because we do all scanning in memory, before the incoming message is ever accepted from the sender. If we identify a message as spam, we refuse to accept it at all, forcing the sending server (if it is indeed a legitimate server) to send an error message back to the sender. In the unlikely event that the sender was legitimate, the error message includes simple instructions about how to resend the message. This approach eliminates virtually all spam in your Inbox without requiring any end-user management of a quarantine folder.