Email security using the simplest of methods!

SPF (Sender Policy Framework) is the first line of defence against email spoofing. The process specifies which servers are authorised to send emails on your behalf.

You publish a special DNS record (TXT record) that lists all authorised IP addresses and mail servers. For every incoming email, the receiving mail server checks whether the sending IP address is listed in the SPF record. If the IP address does not match, the email is flagged as suspicious or rejected.

DKIM (DomainKeys Identified Mail) goes one step further than SPF: it not only ensures that the email originates from an authorised server, but also that the content has not been tampered with in transit.

Every outgoing email is provided with a digital signature generated using a private key. The corresponding public key is published in the DNS. The recipient can verify the signature and thus check the authenticity and integrity of the message.

DMARC (Domain-based Message Authentication, Reporting & Conformance) is the overarching framework for SPF and DKIM. It sets out binding rules on how emails that fail authentication checks should be handled.

You publish a DMARC policy in the DNS, which specifies whether unauthenticated emails should be delivered (none), moved to the spam folder (quarantine) or rejected entirely (reject). In addition, you will receive regular reports on delivery attempts and any potential attempts to misuse your domain.

In email spoofing, attackers manipulate the sender’s address so that the message appears to come from a trusted source - such as your bank, a colleague or a business partner.

The consistent implementation of SPF, DKIM and DMARC makes spoofing considerably more difficult. In addition, staff should receive regular training in recognising suspicious emails.

DNSBL lists are an important tool in the fight against spam. These lists contain the IP addresses of servers known to be sources of spam. Mail servers around the world use these lists to automatically block suspicious emails.

Why this matters to you: If your mail server ends up on a blacklist - for example, because a user has unwittingly sent spam - your legitimate emails will suddenly no longer reach their recipients. At SpeedIT Solutions, we continuously monitor our IP addresses and respond immediately to any suspicious activity.