add app to app communication

Author: cachai2

articles/container-apps/media/networking/peer-to-peer-encryption-traffic-diagram.png

@@ -289,7 +289,9 @@ The following example shows an environment with peer-to-peer encryption enabled.
 
 <sup>2</sup> Traffic to and from the ingress proxy within the environment is TLS encrypted with a private certificate and decrypted by the receiver. 
 
-<sup>3</sup> Calls made from app A to app B are first sent to the edge ingress proxy, and are TLS encrypted.
+<sup>3</sup> Calls made from app A to app B's FQDN are first sent to the edge ingress proxy, and are TLS encrypted.
+
+<sup>4</sup> Calls made from app A to app B using app B's app name are sent directly to app B and are TLS encrypted.
 
 Applications within a Container Apps environment are automatically authenticated. However, the Container Apps runtime doesn't support authorization for access control between applications using the built-in peer-to-peer encryption.