Provisioning differentiated services using programming interfaces for networks

The IETF Differentiated Service (DiffServ) effort aims to create a scaleable framework for realizing traffic differentiation in IP networks. At present, the framework has laid the ground for ar-chitecting routers that provide basic functionalities to support traffic differentiation. How these DiffServ-enabled routers can be put together to form a service network is not mandated by the framework. The open signaling approach, originally proposed for ATM networks defines programming interfaces for switches and routers. End to end services can be created by programming the routers via the standard interfaces using simple signaling mechanisms. This leads to flexible service creation and co-operative behavior of multiple routers in a network. In this paper, we present a behavioral abstraction called virtual link for IP packet forwarding engines. The virtual link abstraction and open signaling are used for provisioning Differentiated Services. The work described herein has been submitted in part, as a contribution to the IEEE P1520.3 working group for standardizing programming interfaces for networks. Implementation experience of the proposed interfaces is presented.