Comparison
Mutual TLSvsWorkload identity
Mutual TLS
both sides present certificates, so the server proves who it is and so does the calling service.
TLS where the client also authenticates with a certificate. It gives strong service-to-service identity with no shared secret in the request, which is why service meshes default to it. The whole difficulty is certificate lifecycle: issuance, rotation and revocation at scale, which is why it is usually adopted with a mesh rather than by hand.
Full entry →Workload identity
the service proves what it is to the cloud without holding any credential, because the platform attests to it.
Giving a running workload a cryptographic identity derived from where and what it is, which other systems can verify, instead of a shared secret it must carry. It is what eliminates long-lived keys in application configuration and what makes mutual TLS between services possible without a certificate distribution problem. It also makes authorisation legible, since policies name the service rather than an opaque key.
Full entry →