Email security is the broader defensive program of sender identity, confidentiality, access control, and safe handling of mail.
It includes filtering, but it also covers how mail is authenticated, stored, encrypted, and how people treat requests that arrive by mail.
How it works
Sender authentication such as SPF, DKIM, and DMARC helps receivers reject forged domains, while encryption protects messages that must stay confidential in transit or at rest.
Access control decides which administrators may open mailboxes, and archiving decides how long a faithful copy remains.
People remain part of the program because a perfectly authenticated message can still ask for a harmful payment.
Training and a second channel for money movement sit beside the technical checks rather than after them as an afterthought.
Concrete examples
- A domain publishes a reject policy so other providers can discard mail that pretends to come from it.
- Executives' mailboxes require a second approval before an administrator can search them.
- A supplier change requested by mail is confirmed through a phone number the company already held.
Protective measures
- Publish and monitor sender authentication for your domains, and align it with the servers that really send your mail.
- Encrypt mail that carries sensitive content, and limit who may search mailboxes or archives.
- Pair technical checks with a second channel for payment and identity changes.
- Review the program when you add a new sending service so authentication and filtering still match reality.