Core-stateless guaranteed rate scheduling algorithms

Abstract

Many per-flow scheduling algorithms have been proposed to provide rate and delay guarantees to flows. It is often argued that the need for maintaining per-flow state and performing per-packet classification seriously limits the scalability of routers that employ such per-flow scheduling algorithms. Consequently, design of algorithms that can provide per-flow rate and delay guarantees without requiring per-flow functionality in the network core routers has become an active area of research. We propose a methodology to transform any guaranteed rate (GR) per-flow scheduling algorithm into a version that does not require per-flow state to be maintained in the core routers. We prove that a network of such core-stateless servers provides the same delay guarantee as a corresponding network of GR servers.