Optimizing DSCP Marking to Ensure VoIP’s QoS over HFC Network

Abstract

Three major factors that can affect Voice over Internet Protocol (VoIP) phone services’ quality, these include packet delay, packet loss, and jitter. The focus of this study is specific to the VoIP phone services offered to customers by cable companies that utilize broadband hybrid fiber coaxial (HFC) networks. HFC networks typically carry three types of traffic that include voice, data, and video. Unlike data and video, some delays or packet loss can result in a noticeable degraded impact on a VoIP’s phone conversation. We will examine various differentiated services code point (DSCP) marking, then analyze and assess their impact on VoIP’s quality of service (QoS). This study mimics the production environment. It examines the relationship between specific DSCP marking’s configuration. This research avoids automated test calls and rather focuses on human made call testing. This study relies on users’ experience and the captured data to support this research’s findings.