Network trafik analiziyle VoIP ses kalitesi ölçümü

In today's global world, the ability to communicate with people in distant locations with the low cost is increasingly important. In the absence of face-to-face interactions, voice communication is considered one of the most effective forms of communication. The increasing expectation levels for better audio performance has led to the need to understand the behavior of audio traffic as it affects end user perceived quality of the voice over the communication networks.This research addresses Voice over Internet Protocol communication systems and focuses on the fundamental understanding and assessment of their voice quality.After presenting basic concepts of VoIP, performance assessment methods are described and then the non-intrusive, objective voice quality assessment method that was developed in this thesis is demonstrated. In this method, real network?s data flows of live VoIP calls were collected in packet-size and analyzed; E-model?s R value and objective MOS value were then calculated.Next, developed methods were tested by designing three different test beds and test scenarios. Voice calls were established by X-Lite and Blink SIP soft phones and monitored by Wireshark software in LAN, WLAN and WAN networks. To estimate the method accuracy, voice quality were investigated subjectively by different end users.Finally, objective and subjective MOS correlation values indicate the assessment method is deemed to be an effective measurement of voice quality.Keywords: VoIP, E-model, MOS, R değeri, Korelasyon değeri