Message Level Encryption (MLE) Overview

Message Level Encryption (MLE) allows your Clients to encrypt upstream data using a combination of an RSA public/private key-pair and an AES session key.

The RSA key-pair can be of 2048- or 4096-bit key length, with longer keys offering additional security, but requiring more processing power for decryption at the server. The AES session key uses the maximum FIPS-recommended length of 256 bits. You can configure your Relays to reduce the load on the Server by decrypting and repackaging the Client data before relaying it.

The RSA public key encrypts the session key and adds it to the AES-encrypted report. At the BigFix Server (or a decrypting Relay) the corresponding RSA private key is used to decrypt the AES session key, which is then used to decrypt the Client report.

There are three levels of report encryption:

Clients require encryption of reports and uploads. The client does not report or upload files if it cannot find an encryption certificate or if its parent relay does not support receipt of encrypted documents.
Clients prefer, but do not require encryption of reports and uploads. If encryption cannot be performed, reports and uploads are done in clear-text.
Clients do not encrypt, even if an encryption certificate is present.

For more information about how to set encryption on Clients, see Enabling encryption on Clients.