The Influence of Router’s DiffServ on VoIP’s Voice Quality

• Main Authors: Guey-jyu Chiang, 江桂菊
• Other Authors: Hsing Mei
• Format: Others
• Language: zh-TW
• Published: 2006
• Online Access: http://ndltd.ncl.edu.tw/handle/42604178524898318736

碩士 === 輔仁大學 === 資訊工程學系 === 94 === Most VoIP service uses Best Effort approach to transmit voice packets in current IP Internet. They provide services without QoS support. Lacking of QoS support has significant impact on transmission of Real-time packets. VoIP packets may be lost, or delayed during the transmission. User may get discontinued voice or even disconnect. Thus, Internet has to provide a good QoS mechanism for VoIP, and the most popular technology available is the Differentiated Service (DiffServ). DiffServ suggests classifying and remarking the packets on Edge Routers and process and transmitting packets on Core Router. Due to the classification of quality level; DiffServ enhances the scalability of Internet. Also by the separation of Edge and Core routers, it enhances the process efficiency of routers in Internet. In this thesis, proper router’s parameter settings for VoIP application are investigated. Following the suggestions, VoIP applications can get good voice quality (such as PSQM value), reduce the packet loss rate, eliminate delay and jitter. Proper setting on parameters can benefit router vendors, VoIP developers, and DiffServ administrators.