How to Secure wcf Services between two application hosted on same machine

Question

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I am having Two Application. Assume First application name is AAA and second application name is BBB. The Application with name BBB are having wcf services. Now i dont want to my wcf services to application AAA . In other words I want to prevent the application AAA consuming my wcf services . These two application are hosted on the same computer. Apart from authentication and authorization what else can be used. Any url or help is much appreciated.

For better understanding I have attached my image

Answer 1

You can try to add some extra logic to WCF Service or BBB. To check the where the incoming request from, if it's from localhost/samemacine, then decline it. Not quite sure how many NICs are there in your server, if there's only one and this approach could be doable.

But, I think the authentication/authorization is the best way to get there.