Authenticating from azure kubernetes function app to on prem windows server

I am new, not sure where to post this but it sounds similiar to the original poster here. I am trying to figure out how to get a azure based kubernetes function app to authenticate with our on premise windows IIS server, preferably using windows authentication. The kubernetes cluster can “see” the on prem server via a azure express route. How can I make this work?

No one knowledgeable in here?

I’m confused by your question, so apologies on that. Can you please clarify: How is your IIS server on-prem an authentication mechanism? Is there a web app running the authentication API?

Also, is your question regarding the development of such scenario or are you looking for networking configuration? As you said, the AKS cluster can connect to the IIS web server via express route, so I’m not sure what you are looking for.