We are deploying our app to the EKS, and have a hybrid situation where some services aren't deployed yet within the EKS cluster.

We want the traffic between services deployed on EC2 instances would be encrypted during communication with services deployed in the EKS.

Both apps deployed on EC2 and pods, are java based app deployed on application server.

What is the best practice to do that.. ? In terms of deploying tls certification on the app server, etc...