SSL Forward Proxy decryption enables the Next-Generation to see potential threats in
outbound encrypted traffic and apply security protections against those threats.
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This? | What Do I Need? |
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No separate license required for decryption when using NGFWs or
Prisma Access.
Note: The features and capabilities available to you in
Strata Cloud Manager depend on your active license(s).
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To enable
SSL Forward
Proxy decryption, set up the certificates required to establish the
Next-Generation Firewall (
NGFW) as a trusted third party (proxy) to
the session between the client and the server. You can use certificates signed by an
enterprise certificate authority (CA) or self-signed certificates generated on the
NGFW as
Forward Trust certificates to authenticate
the SSL/TLS session with the client.
(Best Practice) Enterprise CA-signed Certificates—An enterprise CA can issue a
signing certificate that an NGFW uses to sign the
certificates for sites requiring SSL/TLS decryption. When the NGFW trusts the CA that signed the certificate of the
destination server, it can send a CA-signed copy of the destination server
certificate to the client.
This is a best practice because it streamlines the rollout process. Network
devices typically trust the enterprise CA already (it is usually installed
in the devices’ CA trust storage), so you don’t need to deploy the
certificate on endpoints.
Self-signed Certificates—An NGFW can act as a CA and generate self-signed
certificates that it uses to sign the certificates for sites requiring
SSL/TLS decryption. The NGFW signs a copy of the server
certificate to present to the client and establish an SSL session. This
method requires installation of the self-signed certificates on all network
devices, so that those devices recognize the self-signed certificates.
Self-signed certificates are better for small deployments and proof of
concept (PoC) trials because of the need to install certificates on all
devices.
Additionally, set up a
Forward Untrust certificate for the
NGFW to
present to clients when the server certificate is signed by a CA that the
NGFW doesn't trust. This ensures that clients receive a certificate
warning when attempting to access sites with untrusted certificates.
Generate separate subordinate Forward Trust CA certificates for each NGFW,
regardless of if you use enterprise-CA signed or self-signed certificates. This
practice offers several benefits:
- Enables you to revoke one certificate when you
decommission a device (or device pair) without affecting the rest of the
deployment.
- Reduces the impact in any situation requiring revocation of a
certificate.
- Improves troubleshooting because the CA error message the user sees includes
information about the NGFW the traffic is traversing. If you
use the same Forward Trust CA, you lose the granularity of that
information.
After setting up Forward Trust and Forward Untrust certificates,
create a decryption policy rule to define the traffic you want to
decrypt. Next,
create a decryption profile to apply additional SSL/TLS
controls and checks to the defined traffic. Traffic that matches the rule is
converted to cleartext. The
NGFW blocks and restricts traffic based
on the decryption profile and Security policy rules, then re-encrypts the traffic as
it exits the
NGFW.
When you configure SSL Forward Proxy, the proxied traffic does
not support DSCP code points or QoS.