Decoupling delay and bandwidth in stateless core networks

Abstract

The use of network applications like VoIP, video conferencing and online stock marketing has greatly increased over the past few years. These applications require performance bounds on bandwidth, delay and delay variations otherwise they become useless. The solutions proposed by IETF, an authorized Internet body, for providing performance guarantees are not in favor of Internet’s scalability and robustness. In an attempt to provide guaranteed services Dr. I. Stoica had proposed the Stateless Core (SCORE) architecture as a part of his doctoral work at CMU. The SCORE can support all functionalities of the current Internet. Moreover, it can support guaranteed services proposed by IETF without affecting current Internet’s scalability and robustness. Core Jitter Virtual Clock (CJVC) is the scheduling discipline that provides absolute service guarantee in SCORE domain. The delay bound provided by CJVC depends on the reserved rate of the flow. The coupling of delay and bandwidth is considered to be a drawback of CJVC as the flows requiring low delay bound need to reserve large bandwidth. The well-known stateful guaranteed service disciplines like Weighted Fair Queueing (WFQ) and Delay Earliest Due-Date (D-EDD) also have the same problem. Several solutions like Service Curve based Earliest Deadline (SCED) and Rate Controlled Static Priority (RCSP) have been proposed for the mentioned coupling problem but they are limited to stateful networks. In this thesis, we propose a new scheduling discipline for the same problem but in stateless core network. The proposal is to emulate RCSP scheduling discipline algorithm in SCORE domain. Basic admission control algorithm has also been proposed in the course of emulating the behaviour of RCSP in SCORE architecture.