ciphermail
Ciphermail email encryption gateway (S/MIME, OpenPGP, PDF encryption)
...Ciphermail Email Encryption Gateway is compatible with any existing email infrastructure like Microsoft Exchange and Lotus Notes and has support for S/MIME, OpenPGP and PDF encryption.
Ciphermail Email Encryption Gateway has a built-in CA which can be used to issue X.509 certificates for internal and external users.
For additional security, keys can be securely generated and stored in a tamper proof Hardware Security Module (HSM).
The built-in Data Leak Prevention (DLP) module can be used to prevent certain information to leave the organization via email.
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