A 3rd party site sends its notifications after my web application has completed some action in order to notify me of its success. Receiving a notification item requires a re
You need to learn a little about WCF. See the WCF Developer Center, especially the Beginners Guide.
What you want is to create a simple WCF service that corresponds to the WSDL that they will give you. You will need to implement only the operation (method) that they will call to notify you. You can host a WCF service in IIS along with the rest of your application.
The issue will be how to correlate the notifications with the page you're on in your MVC application.