We are defining new Say A service, also is there already existing service called as B service.
The A communicates with the B.
The existing B has authn/authz in place.
Todays date the A service does TLS handshake and gets Token to communicate with B Service.
Now we want to leverage the istio, which will do authn/authz for us.
We want to know what configurations do on both A and B Service side.
Do we need to remove authn/authz at B Service.

Is there any code repo which you can point, has istio integrated in the service.
Also our deployments are using helm charts.