A Framework for Admission Control over DiffServ using Pre-Congestion Notification
This document describes a framework to achieve an end-to-end Controlled Load (CL) service without the scalability problems of previous approaches. Flow admission control and if necessary flow pre-emption preserve the CL service to admitted flows. But interior routers within a large DiffServ-based region of the Internet do not require flow state or signalling. They only have to give early warning of their own congestion by bulk packet marking using new pre- congestion notification marking. Gateways around the edges of the region convert measurements of this packet granularity marking into admission control and pre-emption functions at flow granularity.