Router Policies to Improve Qos for Real Time Data Transfers In Internet

Abstract

ABSTRACT newlineData transfers in Internet can be broadly classified into congestive and non-congestive. Data newlinetransfers involving large rates of data without taking the carrying capacity and band width newlinerestrictions of the network in account is termed as congestive. But the responsive flows newlinewhich send correct rates after sensing the network traffic and back off when congestion newlineoccurs is called non-congestive data transfers. The growing rate of congestive traffic newlinereduces the congestion adaptability of the Internetwork. There are many strategies like newlineActive Queue Management Schemes (AQM) which helps to restrict such traffic. This newlinestrategy indirectly affects the real-time data transfers adversely because real-time traffic newlineoften uses a non-responsive transport protocol. This situation points to the necessity newlineof tuning existing service differentiation schemes and AQM in favour of non-congestive newlinereal-time data transfers so that such transfers meet their deadlines of throughput and delay. newlineThe problem can be solved either by a scheduling mechanism or by a dropping newlinepolicy which helps the real-time data transfers achieve their Quality of Service (QoS) newlinerequirements without keeping a bias against non-real time data flows. The thesis proposes a newlinedropping policy, Random Early Detection (RED) with Service Differentiation (diffRED) newlineand Scheduling scheme, Priority Queuing for Congestion Avoidance (PQCA) which newlinedifferentiates non-congestive data transfers from congestive data transfers and promotes the newlineformer to a good extent without affecting the deserving quality of congestive traffic. The newlinemain parameters used to measure proposed policies are packet loss rate, throughput and newlinedelay. newlineThe methodology used is to analyze the packet arrived based on packet size as a newlinecriterion to determine whether it is real-time or non-real time and if it is real-time, the packet newlineis exempted from a drop in proposed diffRED policy and scheduled with priority in proposed newlinePQCA policy. newlineExperimental results prove that the throughput for real-time Voice over IP (VoIP