Setting up mutual TLS (mTLS) between enterprise applications and an AI governance proxy

Where mTLS fits in a governance proxy architecture

In this setup, the proxy verifies the certificate presented by each calling application or agent, and each client verifies the certificate presented by the proxy. The verified certificate then becomes the basis for workload identity in policy decisions and audit records.

mTLS implementation sequence

1. Trust modelChoose who issues workload certificates and which CAs the proxy trusts.
2. Two-way configurationRequire client certificates at the proxy and verify the proxy at each client.
3. Identity mappingBind a verified certificate attribute to policy decisions and audit records.
4. Lifecycle and validationAutomate rotation, plan for revocation, and test failure cases before enforcing.

Step 1: Choose a certificate authority and trust model

Start by deciding who issues workload certificates and which certificate authorities (CAs) the proxy trusts. These two decisions define the trust model that every later step depends on.

Step 2: Require and verify certificates on both sides

Configure the proxy to require client certificates, and configure each client to verify the proxy. Both directions must be enforced for the connection to be mutually authenticated.

Step 3: Bind certificate identity to policy and audit logs

Map a stable certificate attribute to workload identity, so that a verified certificate attribute drives policy decisions and appears in audit records.

Step 4: Manage rotation and revocation without outages

Automate certificate rotation, monitor expiry, and plan for revocation before certificates are enforced in production, so that renewals and removals do not interrupt traffic.

Validate and troubleshoot before enforcing

Test failure cases before enforcing mTLS. Each of the following checks should behave as described.

• A connection with no client certificate is rejected.
• A certificate from an untrusted CA is rejected.
• An expired certificate is rejected, and expiry alerts fire ahead of time.
• A client using a name absent from the proxy SAN fails verification.
• Through the load balancer path, audit logs show the workload identity, not the balancer's.
• A valid certificate with no registry entry is denied and logged.