adjustable service level
Context
You have an application that answers request from many clients and you want to have control over quality of service to each client considering application capabilities and the service level agreement that you have with your customers.
Problem
You want to control the time when the application answers and processes requests. The answering application should have the option to deny service even if the requester is authorized to send requests.
Solution
The HUB informs the SPOKE how long it should wait for sending a response request, how long it is it time window and also the ID it should present to the HUB for retrieving response.
See Picture:
http://blogs.geekdojo.net/photos/german/picture8525.aspx