How Does a Secure Email Gateway Work?

A secure email gateway offers a robust framework of technologies that protect against these email-borne threats. It is effectively a firewall for your email and scans both outbound and inbound email for any malicious content. At a minimum, most secure gateways offer a minimum of four security features: virus and malware blocking, spam filtering, content filtering and email archiving. Let's take a look at these features in more detail:

Virus and Malware Blocking

Emails infected with viruses or malware can make up approximately 1% of all email received by an organization. For a secure email gateway to effectively prevent these emails from reaching their intended recipients and delivering their payload, it must scan every email and be constantly kept up-to-date with the latest threat patterns and characteristics.

Spam Filtering

Believe it or not, spam filtering is where the majority of a secure email gateway's processing power is focused. Spam is blocked in a number of different ways. Basic spam filtering usually involves a prefiltering technology that blocks or quarantines any emails received from known spammers. Spam filtering can also detect patterns commonly found in spam emails, such as preferred keywords used by spammers and the inclusion of links that could take the email recipient to a malicious site if clicked. Many email clients also allow users to flag spam messages that arrive in their mailbox and to block senders.

Content Filtering

Content filtering is typically applied to an outbound email sent by users within the company. For example, you can configure your secure email gateway to prevent specific sensitive documents from being sent to an external recipient, or put a block on image files or specific keywords within them being sent through the email system.

Email Archiving

Email services, whether they are in the cloud or on-premise, need to be managed efficiently. Storage has been a problem for email administrators for many years, and while you may have almost infinite cloud storage available, email archiving can help to manage both user mailboxes and the efficiency of your systems. Compliance is also a major concern for many companies and email archiving is a must if you need to keep emails for a certain period of time.