The PKI (public key infrastructure) and notes user ID file can contain self generated encryption keys up to 4096 bits, which can protect your data from most threats

Here you'll find some links to learn about PKI in Notes, how it works with Internet X.509 certificates and User ID encryption keys


"...Notes is the most widely deployed PKI in the world..." Security and Usability:Designing Systems that people can use Page 608

Security Considerations in Lotus Notes and Domino 7 - IBM ...

Encrypting database files at the operating system level

Default setting to encrypt all  incoming mail

Users can create and manage their own private encryption keys.

Port encryption for network traffic

Field level encryption settings

Encryption for database forms

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