> ## Documentation Index
> Fetch the complete documentation index at: https://docs.domino.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Work with CA certificates

Intra-cluster encryption in transit is implemented (if enabled) through a deployed service mesh called [Istio](https://istio.io). At installation, Domino can deploy Istio for Domino use only, or you can configure Domino to leverage an existing deployed Istio mesh on the Kubernetes cluster (potentially shared with other applications). See [Istio](/6.3/admin/configuration/installer-configuration#istio) in Configuration Reference for details.

The following topics explain how to work with Certificate Authority (CA) certificates:

* [Set up custom CA certificates.](/6.3/admin/security-and-compliance/ca-certificates/set-up-custom-ca-certs)

* [Update custom CA certificates.](/6.3/admin/security-and-compliance/ca-certificates/update-custom-ca-certs)