Mime only

S/Mime only text

S/Mime with multiple attachments

There are several signer possible:

Encrypt then Sign / Sign then Encrypt

Sign then Encrypt

Advantages:

• Signer knows the message
• Signature is hidden

Disadvantages:

• Recipient could re-encrypt as someone else
• Integrity not possible

Encrypt then Sign

PGP Default

Advantages:

• Signature ensures integrity of encrypted ciphertext

Disadvantage:

• receiver might not know sender (Recipient could resign it)