When are outgoing rules used?

Outgoing rules are always applied when messages are sent from your domain.
They enable:

• Encryption: To ensure that only the intended recipient can read and decrypt the message.
• Signing: To prove the authenticity and integrity of the message.

Guide: Creating an outgoing rule

1. Create a new route:

Navigate to "Routing" in the menu and click "+". Click on "outgoing" in the first step.

2. Select security protocol:

Choose the desired protocol. Multiple selections are possible:

• S/MIME: For certificate-based encryption and signing.
• PGP: For key-based encryption & signing.
  Tip: More information about the protocols can be found in the Cryptography section.

3. Define sender/recipient:

Specify which messages the rule should be applied to:

• Custom: You can either specify a particular mailbox or use the * operator.
• Group: The rule applies to a predefined group
• All: All outgoing emails are considered in the rule.

Note: If no groups have been created yet, follow the instructions in the Groups section.

4. Set cryptography options:

The following options are available in the dropdown menu, depending on the selected security protocol:

• Encryption rules:
  • Send without encryption
  • Encrypt if possible
  • Only send encrypted
  • Only send if encryption is possible for all recipients
• Signing rules:
  • Send without signing
  • Sign if possible
  • Only send signed
• Algorithms:
  • AES-128
  • AES-192
  • AES-256
  • SHA-256
  • SHA-384
  • SHA-512
• Encryption modes:
  • GCM (Galois/Counter Mode)
  • CBC (Cipher Block Chaining)
• Signature modes:
  • Detached signature
  • Enveloped signature
  • Cleartext signature
• Keys:
  • Encryption with a specific certificate or key.
  • Automatic selection of the appropriate certificate/key from your imported ones. This option is automatically active if you don't select any keys or certificates.

Tip: If you want to use a specific certificate or key, make sure they have been added to the cryptography section beforehand (see "S/MIME" or "PGP" section).

5. Notifications:

Notifications in the email subject are only possible through your mail server.

6. Save rule:

• Review your settings in the summary and click "+". The rule will now be active and appear in the overview.

Notes

• Outgoing rules only apply to messages from your domain as the sender. Messages from external domains cannot be processed.
• Make sure all required certificates or keys are stored in the Cryptography section.