I’m running a WCF Service on IIS. The Service uses “webHttpBinding” and

<security mode="Transport">
   <transport clientCredentialType="Windows" />
</security>

Then I’m doing some ajax calls from my webapp.

1. request witch takes really long
2. multiple short calls every 1s for status updates

Im running my app on http://localhost and everything works just fine. But when I’m running my app on the server on https://dev.server.com the requests are sent to the server but they have to wait until the first very long request is done. So this leads to very long “waiting for server response” times in the short requests.

How could this be? I mean it’s the same service and same requests – why is localhost parallel and from the dev-server its serial?